Free Oral Sessions Abstracts

FREE ORAL SESSIONS Oral I - Haemostasis O-01

O-02

Routine intraoperative thromboelastography reduces blood transfusions in paediatric cardiac surgery

Haemodilution during cardiopulmonary bypass in paediatric cardiac surgery does not influence thromboelastography

Birgitta Romlin, Håkan Wåhlander, Fariba Baghaei, Håkan Berggren, Anders Jeppsson, Krister Nilsson Department of Paediatric Anaesthesia and Intensive Care, Queen Silvias Children Hospital, Gothenburg, Sweden Introduction. Cardiac surgery with the use of cardiopulmonary bypass induces a haemostatic derangement which may lead to bleeding complications and subsequent transfusion of blood products. Dynamic intraoperative monitoring of perioperative haemostasis with thromboelastography has gained a lot of interest during the last years but its value in paediatric cardiac surgery is yet unclear. The aim of the present study was to assess whether routine use of intraoperative thromboelastography reduces blood transfusions in paediatric cardiac surgery without compromising safety. ® Method. Modified rotational thromboelastograpy (ROTEM ) with HEPTEM and FIBTEM analyses on cardiopulmonary bypass (CPB) and INTEM, HEPTEM and FIBTEM analyses immediately after CPB, were performed in 45 consecutive paediatric heart surgery patients. Thromboelastographic data was used in combination with clinical observations (bleeding tendency, haemodynamics) and routine laboratory analyses (haematocrit, haemoglobin) to determine the need of transfusion. Red blood cells, plasma and platelets transfusion volumes, percentages of patients receiving transfusions, postoperative drain loss and haemoglobin level postoperative day 1 were registered and compared to a control group of 60 consecutive patients where transfusion decisions were determined solely on clinical observations and routine laboratory analyses. Results. The groups were comparable regarding age, gender, weight, preoperative haemoglobin levels, operative procedures and CPB time. Median transfused volumes of red blood cells and plasma were significantly reduced in the thromboelastography group (P=0.009 and P<0.001 respectively) while platelet transfusion volume increased (P=0.004). Routine thromboelastography reduced the percentage of patients receiving red blood cell (from 78% to 58%, P=0.032) and plasma (from 78% to 18%, P<0.001) transfusions while patients receiving platelets transfused increased (from 12% to 38%, P=0.002). Overall the percentage of patients receiving any transfusion of blood products decreased from 93% to 64% (P<0.001). Mean drain loss (128±87 vs. 128±74 mL/24h, P=0.95) and postoperative haemoglobin levels (122±16 vs. 123±16 g/L, P=0.95) did not differ between the two groups. Discussion. Routine use of intraoperative thromboelastography can reduce the overall transfusion rate in paediatric cardiac surgery patients by 30%, without compromising postoperative blood loss and haemoglobin levels. Reference. 1. Osthaus W. Boethig D, Johanning K, et al. Whole blood coagulation measured by modified thrombelastography (ROTEM) is impaired in infants with congenital heart disease: Blood Coag Fibrinolysis 2008; 19: 220-225.

Birgitta Romlin, Håkan Wåhlander, Håkan Berggren, Fariba Baghaei, Anders Jeppsson, Krister Nilsson Department of Paediatric Anaesthesia and Intensive Care, Queen Silvias Children Hospital, Gothenburg, Sweden Introduction. Cardiac surgery with the use of cardiopulmonary bypass (CPB) induces haemostatic alterations, which may lead to bleeding complications. Early identification and quantification of the haemostatic derangements increases the possibilities of countermeasures. Thromboelastography can be used to monitor intraoperative haemostasis but its value during CPB is not clear since the inevitable haemodilution during bypass may influence the results. The aim of the present study was thus to compare thromboelastography data measured before and after modified ultrafiltration. Method. Forty-five patients undergoing paediatric cardiac surgery (mean age 2.4±3.6 years, 51% girls) were included in a prospective observational study. Samples for modified rotational ® thromboelastography (ROTEM with HEPTEM clotting time (CT), clot formation time (CFT) and maximum clot formation (MCF) and FIBTEM MCF, and haematocrit were collected during CPB before and after modified ultrafiltration. Variations between the two samples were calculated and are given in % with 95% confidence intervals. Correlation coefficients between the two samples were calculated according to Pearson. Results. Haematocrit was 27.8% (26.9 - 28.6) before and 36.9% (35.5 - 38.2) after ultrafiltration (P<0.001). Mean variation in HEPTEM CT was 9.8% (1.0 - 18.9), in HEPTEM CFT 3.0% (-0.4 – 16.4), in HEPTEM MCF 2.9% (-0.4 – 6.3) and in FIBTEM MCF -2.3% (-13 - 9). Correlation coefficients before and after ultrafiltration were for HEPTEM CT 0.61, HEPTEM CFT 0.93, HEPTEM MCF 0.86 and FIBTEM MCF 0.87 (P<0.001 for all). Discussion. The variation of thromboelastography data measured before and after ultrafiltration is acceptable and the correlation is excellent. Thromboelastography to identify haemostatic disturbances can be performed before ultrafiltration during CPB, increasing the possibility of early initiation of therapeutic measures. References. 1. Osthaus W. Boethig D, Johanning K, et al. Whole blood coagulation measured by modified thrombelastography (ROTEM) is impaired in infants with congenital heart disease. Blood Coag Fibrinolysis 2008; 19: 220-225. 2. Shore-Lesserson L. Manspeizer HE, Deperio M, et al. Thromboelastography-guided transfusion algorithm reduces transfusions in complex cardiac surgery. Anesth Analg 1999; 88: 312-319.

Journal of Cardiothoracic and Vascular Anesthesia, Vol 23, No 3S (June Supplement), 2009: pp S1-S35

S1

S2

FREE ORAL SESSIONS

O-03

O-04

Thrombin dynamics in cardiac surgical patients

Transfusion of shed mediastinal blood reduces the use of allogeneic blood transfusion without increasing complications

Susanne Lison, Michael Spannagl, Wulf Dietrich Department of Anaesthesiology, Ludwig Maximilians University of Munich, Munich, Germany

Lars Folkersen, Niels Grunnet, Carl-Johan Jakobsen Aarhus University Hospital, Skejby, Aarhus, Denmark

Introduction. Cardiac surgical procedures requiring cardiopulmonary bypass (CPB) activate a variety of haemostatic processes which promote systemic thrombin generation, despite full heparinization [1]. In contrast to commonly used coagulation tests, thrombin generation tests assess the whole kinetics of thrombin generation over time [2]. A further development of previous methods is presented by the thrombin dynamics test (TDT) [3]. The aim of the present study was to evaluate the thrombin dynamics measured by TDT in the course of CPB. Method. After institutional ethics committee approval and informed patient consent, 220 patients undergoing coronary artery bypass grafting or valve surgery were prospectively enrolled in this randomized study. In addition to standard perioperative procedures, all patients received aprotinin (A) or tranexamic acid (TA) for their antifibrinolytic properties. Blood samples were taken before induction of anaesthesia (preop), at the end of the surgery (postop), 4 hours postop (4h postop), and the morning of days 1, 3, and 5 postoperatively (POD 1,3,5). In TDT thrombin formation is detected with a fast chromogenic substrate being readily converted by thrombin. Parameters: the thrombin onset time (sec) and the peak value of the first derivative representing the maximum velocity of the conversion of the thrombin substrate (thrombin dynamics, %). Besides TDT, additional molecular markers of thrombin generation were obtained. Results. Compared to baseline, thrombin dynamics in both groups were significantly reduced postop (P<0.001). On POD 1 significantly elevated TDT (%) was found (P<0.001); TDT returned to preop values on POD 3. Separate analysis of A and TA showed significantly reduced thrombin dynamics in A compared to TA postop and on POD 1. preop A/TA TDT (%)

postop A/TA

4h postop A/TA

POD 1 A/TA

POD 3 A/TA

POD 5 A/TA

97

82

96

100

98

98

97 98°

81 86**

96 96°

99 101*

97 98°

96 99°

Note: values are median, ° not significant, * P<0.05, **P <0.001

Discussion. Thrombin generation tests measure the timedepending changes in thrombin concentration which may reflect in-vivo conditions more closely. TDT in particular, focuses on the initial dynamics of thrombin. After CPB, changes in the thrombin dynamics were observed until POD 1. Regarding A and TA separately, perioperative thrombin dynamics showed significant reduced levels after aprotinin. References. 1. Boisclair MD, Lane DA, Philippou H, et al. Mechanisms of thrombin generation during surgery and cardiopulmonary bypass. Blood 1993; 82: 3350-3357. 2. Hemker HC, Gliesen P, Al Dieri R, et al. Calibrated automatic thrombin generation measurement in clotting plasma. Pathophysiol Haemost Thromb 2003; 33: 4-15. 3. Calatzis A. Reininger AJ, Spannagl M, et al. Rapid and automated quantification of the kinetics of thrombin formation using the Thrombin Dynamics Test (TDT). J Thromb Haemost 2003; S1: 1589.

Introduction. The conservation of the patient’s blood and prevention of allogeneic transfusion is important. The use of retransfusion of shed mediastinal blood (SMB) in cardiac and thoracic aortic surgery is still under debate [1,2]. The aim was to evaluate the efficacy, cost effectiveness and safety of autotransfusion (re-transfusion of SMB). Method. At a University hospital a retrospective study was made of 624 consecutive cardiac patients from three successive periods: 1) with autotransfusion, n= 244, 2) without autotransfusion, n=180, 3) with autotransfusion, n=200. Data was collected from the Transfusion Services Database and cross matched with perioperative data from the West Danish Heart Registry. Data collection was performed prospectively. Results. The percentage of patients transfused with allogeneic blood significantly increased from 36.1% to 51.3% after withdrawal of autotransfusion (P<0.001) and decreased to 40.7% (P<0.01) after re-establishing autotransfusion of SMB. Patients received overall a higher volume of blood products in the period without autotransfusion although only red cells were statistically significant. Use of SMB reduced the average need of allogeneic red cell transfusion from 3.41 to 2.14 (P=0.04) units. Using conservative estimates the costs were reduced almost €300 per case. No significant differences in postoperative bleeding or infections were found between groups. Table 1. Number (%) of patients receiving transfusion All Red cells

Plasma

Platelets

products

Autotransfusion 1

88 (36.1)

62 (25.4)

58 (23.8)

104 (42.6)

No Autotransfusion

97 (51.3)

52 (27.5)

55 (29.1)

107 (56.6)

Autotransfusion 2

77 (40.7)

48 (25.4)

47 (24.9)

88 (46.6)

Conclusion. Autotransfusion of SMB significantly reduced allogeneic red cell transfusion and seemed cost effective and safe. References. 1. Dial D, Dao Nguyen D, and Menzies D. Autotransfusion of shed mediastinal blood. Chest 2003; 124; 1847-1851. 2. Martin J, Robitaille D, Perrault LP, et al. Reinfusion of mediastinal blood after heart surgery. J Thorac Cardiovasc Surg 2000; 120: 499-504. O-05 Assessment of optimal protamine-heparin reversal ratio by modified thromboelastometry (ROTEM) in cardiac surgery Nejma Mabrouk-Zerguini, Vincent Bréant, Julien Clarissoux, Elisabeth Vaissier, Stéphane Aubert, Pierre Coriat, Alexandre Ouattara General Hospital la Pitié-Salpêtrière, Paris, France Introduction. Modified thromboelastometry (ROTEM) might identify heparin or protamine excess in vitro [1]. The goal of our observational study was to know whether ROTEM could be helpful to determine the optimal protamine-heparin reversal ratio (R) in routine cardiac surgery.

FREE ORAL SESSIONS

S3

Method. After approval by ethical committee, we included prospectively 2 groups of patients according to the presence of full (group F, n=12) or partial (group P, n=12) heparin reversal. We collected demographic data, preoperative medications, and preand post-CPB activated clotting time (ACT), routine haemostasis tests, and ROTEM parameters. A residual heparin excess was diagnosed by the ROTEM by a prolonged clotting time (CT) on INTEM and a CT INTEM/HEPTEM ratio >1. A protamine excess was diagnosed by a prolonged CT-INTEM and CTHEPTEM, a CT INTEM/HEPTEM ratio =1 and a prolonged CTEXTEM. Results. Preoperative data, antifibrinolytic drugs and CPB duration were similar between groups. In group P, R was 85±5%, thrombin time and ACT (121±10 vs. 125±8 s, NS) were not significantly different before and after CPB, CT- INTEM did not increase (171±38 vs. 161±54 s, NS), and the CT INTEM/HEPTEM ratio was 0.95±0.08 post-CPB. In group F, ACT was significantly increased after CPB (119±14 vs. 134±14 s, P=0 03), and CT- EXTEM also increased significantly (58±8 s vs. 70±9 s, P=0.008). In this group, the post-CPB CT INTEM/HEPTEM ratio was 0.95±0.08. Postoperative bleeding and standard haemostasis tests were similar between groups. Conclusion. In routine cardiac surgery, partial reversal of heparin (i.e. 85%) seems to provide an optimal haemostasis profile and thus, should be preferentially performed. Conversely, full reversal induced an increase in ACT and ROTEM abnormalities compatible with a protamine excess hypocoagulant profile. The absence of clinical impact could be explained by the small difference between reversal ratios between groups. These preliminary results should be confirmed by further studies including a larger number of patients. References. 1. Mittermayr M, Margreiter J, Velik-Salchner C, et al. Effect of protamine and heparin can be detected and easily differentiated by modified thromboelastograohy (ROTEM): an in vitro study. Br J Anaesth 2005; 95(3): 310-316.

Whole blood multiple electrode aggregometry (MEA) was performed following stimulation with thrombin receptor activating peptide (TRAPtest, 32 µM) and arachidonic acid (ASPItest, 0.5 mM). Repeated measurement ANOVA with a Bonferroni correction for multiple comparisons was performed to detect differences between time points. Assay imprecision was determined by calculating the coefficient of variation. The level of statistical significance was set to P <0.05. Results. Platelet aggregation by arachidonic acid (ASPItest) was markedly decreased 4 h after aspirin intake. From the second day after aspirin intake, ASPItest values recovered with high inter-individual variability, and five days after aspirin intake, ASPItest values did not differ significantly from baseline. TRAPinduced platelet aggregation (TRAPtest) showed no systematic changes during the study period. The resting time of the sample did not affect TRAPtest or ASPItest values. The coefficients of variation were 10% for the ASPItest and 7% for the TRAPtest. Conclusions. MEA reliably detected the effects of aspirin. Notably, 500 mg aspirin caused complete inhibition of arachidonic acid-induced platelet aggregation for two days in all volunteers. Aggregation returned to baseline values with a wide interindividual variation in time course by day five. No resting time for the blood sample was required for ASPItest or TRAPtest. These assays can be implemented as real point-of-care tests. The reproducibility of the assays studied here is within the range of modern point-of-care analysers.

O-07 Point-of-care assessment of CPB-induced platelet dysfunction and the effect of DDAVP using multiple electrode aggregometry (MEA) 1

1

2

Christian Weber , Christian Hofstetter , Wulf Dietrich , Csilla 2 Jambor 1

O-06 Whole blood multiple electrode aggregometry (MEA) is a reliable point-of-care test of aspirin-induced platelet dysfunction 1

2

1

Csilla Jambor , Christian Weber , Wulf Dietrich , Bernhard 1 1 1 Heindl , Michael Spannagl , Bernhard Zwissler 1

Clinic for Anesthesiology, University of Munich, Munich, Ger2 many, Department of Anesthesiology, Intensive Care and Pain Medicine, Goethe-University Frankfurt, Frankfurt am Main, Germany Introduction. Aspirin is one of the most commonly ingested over-the-counter drugs. In addition to its analgesic and antiinflammatory actions, it also potently inhibits platelet aggregation. Evaluation of aspirin-induced platelet dysfunction is relevant in various clinical situations, including during complex surgery with a high bleeding risk in individuals who have ingested aspirin. In this study, we examined the suitability of multiple electrode aggregometry (MEA) for time course assessment of the anti-platelet effects of a single oral dose of 500 mg aspirin. We also determined the applicability of this method in the pointof-care (POC) setting by comparing the results of the test after different time intervals following blood sampling. Method. Following approval by the local ethics committee, twenty-four adult volunteers provided written informed consent and were enrolled in the study. After blood drawn at baseline, 500 mg aspirin was administered to all volunteers. Blood samples were taken at 4, 24, 56, 80 and 124 hours after aspirin ingestion. At each time point, measurements were performed immediately and 30 and 60 minutes after withdrawing blood.

Department of Anesthesiology, Intensive Care and Pain Medicine, Goethe-University Frankfurt, Frankfurt am Main, Germany, 2 Clinic for Anesthesiology, University of Munich, Munich, Germany Introduction. Blood loss following cardiac surgery can be caused by acquired platelet dysfunction after CPB. Monitoring of platelet function is clinically important for identification of these patients. DDAVP has been shown to augment platelet function and to reduce blood loss in patients with platelet dysfunction. In this study, we examined the feasibility of whole blood multiple electrode aggregometry (MEA) for detection of CPB-induced platelet dysfunction and investigated its ability to monitor DDAVP treatment. Method. With the approval of the local ethics committee, fiftyeight consecutive patients with blood loss exceeding 150 mL/h in the first two hours after cardiac surgery were screened for isolated platelet dysfunction. The diagnosis of platelet dysfunction was made when conventional coagulation analysis (platelet count, aPTT, INR, fibrinogen) were within normal ranges and no surgical cause of bleeding was suspected. Twenty-two patients were finally enrolled in the study. Eleven patients received 0.3 µg/kg DDAVP and eleven patients received no therapy in a nonrandomized setting. Multiple electrode aggregometry was performed following stimulation with thrombin receptor activating peptide (TRAPtest, 32µM), adenosine diphosphate (ADPtest, 6.4µM) and arachidonic acid (ASPItest, 0.5mM) prior to and two hours after intervention. Conventional laboratory parameters and hourly blood loss were recorded. Mann-Whitney test was used to detect differences between the groups and Wilcoxon test to detect differences before and after intervention. Spearman correlations were performed to investigate the association between laboratory parameters and blood loss.

S4

FREE ORAL SESSIONS

Results. All enrolled patients showed platelet dysfunction, manifested as impaired platelet aggregation in MEA before intervention. After intervention, platelet function improved in the DDAVP group [49 (30/72)U median (25th/75th percentile) vs. 15 (8/21)U for ASPItest (P<0.001); 35 (24/54)U vs. 14 (7/28)U for ADPtest (P=0.002); and 85 (66/115)U vs. 64 (26/88)U for TRAPtest (P=0.007)]. In contrast, MEA remained unchanged in the control group [22 (10/50)U vs. 33 (14/57)U for ASPItest (P=0.175); 17 (12/20)U vs. 14 (10/28)U for ADPtest (P=0.147); 65 (41/89)U vs. 57 (30/91)U for TRAPtest (P=0.123)]. Hourly blood loss after intervention was lower in the DDAVP group than the control group. Arachidonic acid-induced platelet aggregation (r=-0.46, P=0.03) and ADP-induced platelet aggregation (r= -0.54, P=0.009) were correlated with postoperative blood loss. The areas under the receiver operating characteristic curves suggesting the ability to indicate increased blood loss were 0.74 for ASPItest (P=0.053) and 0.80 (P=0.017) for ADPtest. Conclusions. Impaired platelet function following cardiac surgery and the effect of DDAVP can be assessed at the bedside using MEA. This device might be helpful for identification of patients who benefit from DDAVP therapy. O-08 Increased rate of convulsive seizures following administration of tranexamic acid Michael Sander1, Claudia Spies1, Viktoria Martiny1, Thomas 1 2 1 Volk , Herko Grubitzsch , Christian von Heymann 1

2

Dept. of Anaesthesia and Intensive Care Medicine, Dept. of Cardiothoracic Surgery, Charité, Berlin, Germany Introduction. Antifibrinolytic agents are commonly used during cardiac surgery to minimize bleeding and to reduce exposure to blood products. In 2006, the use of aprotinin became controversial when the drug was associated with an increased risk of renal failure, myocardial infarction, stroke, and death in a large observational study [1,2]. Subsequent cohort studies also linked aprotinin to an increased risk of death [3]. Therefore, the aim of this study was to evaluate the efficiency and the safety profile of tranexamic acid (TXA) compared to aprotinin by an observatory study. Method. After publication of the first Mangano paper raising concerns about the safety profile of aprotinin we changed our

routine administration of antifibrinolytics to 50 mg/kg TXA prior to CPB and 50 mg/kg into the priming fluid of the CPB. Prior to this paper all patients received aprotinin after sternotomy in a 6 dose of 1.5x10 KIU. After informed consent for this retrospective observational study we included 893 patients (336 receiving TXA and 557 receiving aprotinin) into our final analysis. Efficiency was evaluated by the need for transfusion of blood products and total postoperative blood loss. Safety was evaluated by routinely monitored biomarkers and the diagnosis of myocardial infarction, ischaemic stroke, intracerebral haemorrhage, convulsive seizures, acute renal failure and pericardial tamponade during ICU and IMCU stay. Data is provided as mean and standard deviation or percentage of patients in the respective groups. Results. Patients’ baseline characteristics and surgery related data did not differ between groups. The rate of convulsive seizures was increased in patients receiving TXA (3.0% vs. 0.5%; P<0.01). Patients receiving TXA had increased total postoperative blood loss during the first 48 h ICU stay (729 mL (833) vs. 510 mL (730); P<0.01), increased rate of surgical re-exploration (6.8% vs. 1.8%; P<0.01) and 50.9% vs. 37.3% patients received red blood cell transfusion (P<0.01). No difference regarding biomarkers, myocardial infarction, ischaemic stroke, intracerebral haemorrhage, acute renal failure and pericardial tamponade was observed. Discussion. The minor efficiency of TXA and the increased rate of transfusion, surgical re-exploration and a higher rate of convulsive seizures warrant critical reconsideration of routine administration of TXA. Further prospective studies evaluating the efficacy and safety profile of TXA are urgently needed. References. 1. Mangano DT, Tudor IC, Dietzel C. The risk associated with aprotinin in cardiac surgery. N Engl J Med 2006; 354: 353365. 2. Mangano DT, Miao Y, Vuylsteke A, et al. Mortality associated with aprotinin during 5 years following coronary artery bypass graft surgery. JAMA 2007; 297: 471-479. 3. Schneeweiss S, Seeger JD, Landon J, et al. Aprotinin during coronary-artery bypass grafting and risk of death. N Engl J Med 2008; 358: 771-783.

Oral II – Cardiopulmonary Bypass O-09 Epidural anaesthesia in elderly patients undergoing CABG Massimiliano Nuzzi, Elena Bignami, Giovanni Landoni, Valentina Testa, Anna Mizzi, Francesco Alfredo Garozzo, Remo Daniel Covello, Alberto Zangrillo Ospedale San Raffaele - Università Vita-Salute San Raffaele, Milano, Italy Introduction. The purpose of the present study was to evaluate the effects of thoracic epidural anaesthesia on the release of postoperative N-terminal pro B-natriuretic peptide (NT-proBNP) in elderly patients undergoing elective coronary artery bypass grafting. Method. The enquiry consisted of a case matched study on 92 elderly patients (>65 years) undergoing elective coronary artery bypass grafting. Forty six consecutive patients receiving general

and epidural anaesthesia were case matched (preoperative medications, ejection fraction, comorbidities) with 46 control subjects who received general anaesthesia only. Results. The primary outcome measure was postoperative NTproBNP release. Median (interquartile range) plasma concentration of NT-proBNP before surgery was 402 (115-887 pg/mL) in the epidural group versus 508 (228-1285 pg/mL) in the control group (P=0.9) while 24 hours after surgery it increased to 1846 (1135-3687 pg/mL) versus 5005 (2220-11377 pg/mL), P=0.001. There were more patients (P=0.043) in the control group (9/46=19.5%) than in the TEA group (4/96=8.8%) with an intensive care unit stay longer than 4 days. A multivariate analysis that included all pre- and intraoperative factors showed that the absence of preoperative β-blocker therapy (OR: 3.94; 95% CI: 1.123-13.833; P=0.03) and the absence of epidural catheter (OR: 3.91; 95% CI: 1.068-14.619; P=0.04) were the only variables independently associated with a prolonged intensive care unit stay.

FREE ORAL SESSIONS

S5

Conclusions. Epidural, added to a standard general anaesthetic for CABG significantly attenuates NT-proBNP release in elderly patients and could be associated with a reduced incidence of prolonged intensive care unit stay. Figure 1. NT-proBNP in the 46 patients with epidural anaesthesia (median, interquartile and range values in a logarithmic scale) compared to the 46 patients who received general anaesthesia only.

postoperative NT-proBNP values, pg/m l

87584

12713 3687 1846

1000

O-11 The effects of deep hypothermic circulatory arrest on endotracheal tube leakage: preliminary results

100000

10000

References. 1. Grayson AD, Khater M, Jackson M, et al. Valvular heart operation is an independent risk factor for acute renal failure. Ann Thorac Surg 2003; 75: 1829-1835. 2. Haase M, Haase-Fielitz A, Bagshaw SM, et al. Cardiopulmonary bypass-associated acute kidney injury: a pigment nephropathy? Contrib Nephrol 2007; 156: 340-353.

1135 430

11377 5005 2220 718

100

10 Epidural Group

David Rubes, Jan Kunstyr, Jan Blaha, Jaroslav Lindner, Martin Stritesky, Michal Matias

General Anesthesia Group

O-10 Release of plasma free haemoglobin during cardiopulmonary bypass in heart valve surgery Jan Spegar, Jana Snircova, Tomas Vanek, on behalf of the MSM0021620817 study group Department of Cardiac Surgery, 3rd Faculty of Medicine, Charles University Prague, Prague, Czech Republic Introduction. Heart valve surgery carries a higher threat of renal insufficiency as an independent risk factor due to prolonged cardiopulmonary bypass (CPB) [1]. Multiple causes of CPB associated renal damage has been described, including haemoglobin induced renal injury [2]. Method. Forty-three patients scheduled for heart valve surgery (mostly combined) were enrolled in the prospective study. Plasma free haemoglobin (PFH) levels were evaluated by photocolorimetric measurement at the start (t0) and before the end of CPB (t1). Results. A statistically significant increase of PFH levels during CPB was detected [geometric mean (interquartile range) - t0: -1 -1 73.1 (53.4) mg·L , t1: 339.9 (352.2) mg·L ], P=0.002. Significant regression relationship between the duration of CPB and increased PFH levels was found [Spearman’s correlation coefficient (rs) 0.628, P<0.001]. In some elderly patients the tendency toward high release of PHF during CPB was pronounced but the overall association between age and PHF levels was on borderline significance (P=0.078). The correlation between PFH levels and post-operative (days 1-4) serum creatinine (and other RIFLE classification criteria) was low and non-significant but the latter correlated highly with pre-operative serum creatinine values (rs reached values 0.6-0.7, P<0.001). Discussion. Even though a CPB time-dependent increase in PFH levels was clearly detected, the real clinical impact of this finding seems to be weak. The cause of CPB associated renal injury is broadly multifactorial and the patients with existing preoperative kidney dysfunction are a markedly higher risk for postoperative renal impairment.

General Teaching Hospital, 1st Medical Faculty, Charles University, Prague, Czech Republic Introduction. After several cases of pneumonia following the use of deep hypothermic circulatory arrest (DHCA) in our institution, we decided to investigate the effects of deep hypothermic circulatory arrest on endotracheal tube leakage. Method. After local research ethics committee approval and written informed consent was obtained, patients were randomized either into interventional group (intracuff pressure monitored and kept between 2.5-3 kPa) or in non-interventional group (intracuff pressure only monitored). A Kendall Curity tracheal tube was used without lubricant. Intracuff pressure (ITCP) was recorded and alternatively corrected in interventional group at 36, 30, 20, 16, 20, 30 and 36 oC during cardiopulmonary o bypass and DHCA. At 16 C five mL of 1% methylene blue was instilled above the tracheal cuff using a catheter. Fibreoptic bronchoscopy was performed when the temperature reached 36 o C by an observer who was blind to the interventional procedure. Results. Since August 2008 until now 5 patients were randomized into the interventional group and 5 patients were randomized into the non-interventional group. The lowest ITCP in the non-interventional group correlated with the lowest temperature (DHCA period) and was 0.8 kPa. In 4 of the 5 patients in the interventional group it was necessary to correct the ITCP in order to keep the pressure within defined limits. Dye leakage occurred in 3 of 5 patients in the non-interventional group and in none of patients in the interventional group. Conclusion. Preliminary results of our study suggest, that precise monitoring of ITCP during DHCA lowers the possibility of micro-aspiration. The clinical significance of this observation is being further investigated in our institution. Reference. 1. Souza Neto EP, Piriou V, Durand PG, et al. Influence of temperature on tracheal tube cuff pressure during cardiac surgery. Acta Anaesthesiol Scand 1999; 43: 333–337. O-12 Same temperature during different techniques of CABG. What is the microcirculation reaction? Boris Akselrod, Irina Tolstova, Andrey Yavorovskiy, Armen Bunatian National Research Centre of Surgery RAMS, Moscow, Russian Federation Introduction. The purpose of the current study was to compare microcirculation disturbance during myocardial revascularization on the beating heart or during normothermic cardiopulmonary bypass (CPB).

S6

Method. Ten off-pump patients (Gr. 1) and ten on-pump patients (Gr. 2) were examined. Microcirculation was evaluated by wavelet transformation of the laser Doppler flowmetry (LDF) signal. LDF signal from the index finger, arterial pressure, local and core temperature were simultaneously recorded before start, in the main stage (revascularization on the beating heart or during cardiopulmonary bypass (CPB)) and at the end of operation. CPB was conducted with temperature (35.5-36.0°C). -1 2 Pump flow rates were kept 2.5 L min m , mean arterial pressure (MAP) between 65 and 75 mmHg. Results. In Gr. 1 total perfusion decreased only at the end of operation (18.4±6.72 to 11.0±6.66 perfusion units (p.u.), P<0.05). In Gr. 2 a difference was seen during the main stage of operation (17.9±5.45 to 11.9±6.33 p.u., P<0.05) and stayed on this level to the end of operation (10.9 p.u.). In Gr. 1 neurogenic tone increased only at the end of operation (2.34±0.67 to 3.2±1.11 p.u., P<0.05). In Gr. 2 neurogenic tone increased after the main stage of operation (2.10±0.57 to 3.65±1.20 p.u., P<0.01) and at the end was more (2.10±0.57 to 3.01±1.17 p.u., P<0.05). Neurogenic tone was more in Gr. 2 then in Gr. 1 in the main stage (P<0.05). Myogenic tone decrease only at the end of operation (Gr. 1 6.00±3.05 to 3.94±1.63 p.u., P<0.05; Gr. 2 from 5.98±3.20 to 3.85±1.12 p.u., P<0.05). Our study showed increasing neurogenic tone during non-pulsatile normothermic CPB, the same as hypothermic (30-32°C) CPB. In the same temperature conditions CPB caused more increasing neurogenic tone than during of-pump CABG. Conclusions. Increase of neurogenic tone is one of the major reasons for decreased perfusion in the microcirculation during CABG. Normothermic on-pump CABG (t=36.0°C) results in more microcirculatory disturbance than occurs with CABG on the beating heart. O-13 The efficacy and safety of tight blood glucose control during heart surgery: a systematic review and meta-analysis Peter Alston, Rebecca Grounds, Kristin Haga, Gordon Carter, Scott Clarke, Robert Loveless, Daniel Glyde, Katie McClymont, Bonnie Ng University of Edinburgh School of Medicine, Edinburgh, United Kingdom Introduction. Tight blood glucose control in critical care has been associated with improved outcomes but may result in more episodes of hypoglycaemia [1]. The aim of this study was to systematically review the literature to determine the efficacy and safety of tight blood glucose control during heart surgery. Method. A literature search of the major databases was performed and the reference lists of identified papers were hand searched. Identified studies were critically appraised. Inclusion criteria were randomized controlled trials (RCTs), patients undergoing heart surgery and explicit definitions of ‘tight’ and ‘normal’ control of blood glucose. Results. Nine of the 51 identified RCTs met the entry criteria and only four outcomes were suitable for meta-analysis. Tight blood glucose control reduced the incidences of atrial fibrillation (AF) (odds ratio (OR) 0.76 [95%CI 0.58, 0.99]) and the use of epicardial pacing (OR 0.32 [95%CI 0.17, 0.60]) as well as reducing the durations of mechanical ventilation (mean difference (MD) -0.36 [95% CI -3.85, -3.54] hours) and stay in the intensive care unit (ICU) (MD -0.57 [95%CI –0.60, -0.55] days). Heterogeneity was high for the incidences of AF (I 2 55%) and pacing 2 (I 75%) and extremely high for the durations of mechanical 2 2 ventilation (I 94%) and ICU stay (I 99%). Only one study found ‘tight’ blood glucose control to be associated with significantly more episodes of hypoglycaemia.

FREE ORAL SESSIONS

Discussion. Tight blood glucose control during heart surgery appears to be safe and to be associated with beneficial effects on outcome following heart surgery. However, these findings are greatly limited by their high levels of heterogeneity. Conclusion. A well-designed and conducted RCT is required to determine efficacy and safety of tight blood glucose control during heart surgery. Reference. 1. van den Berghe G, Wouters P, Weekers F, et al. Intensive insulin therapy in the critically ill patients. N Engl J Med 2001; 345: 1359-1367. O-14 Influence of pump prime on postoperative acid-base status after elective CABG surgery: 6% HES 130/0.4 versus Gelatin Joris Vermassen, Ongenae Vanoverschelde Henk

Marc,

Donadoni

Ruggero,

AZ Maria Middelares, Gent, Belgium Introduction, After cardiac surgery, metabolic acidosis is a frequent complication. In this prospective randomized controlled study we investigated if choice of pump prime might contribute to this phenomenon after CABG surgery. Method. After informed consent, 112 electively scheduled paR tients were randomly allocated to 6% HES (Voluven , n=52 ) or R gelatin (Geloplasma , n=60 ) CPB priming. Peroperatively, hyperglycaemia was aggressively treated by insulin continuous infusion. Postoperatively, blood was tested for acid-base status, strong ions, lactate and albumin. Stewart’s biophysical approach was used and data analysis was done with unpaired t-test. Results. Postoperative pH was significantly lower in the HES-group -5 (7.42 vs. 7.46 with P=4.10 ) with significantly lower base excess (-0.30 vs. 0.80, P=0.02 ) and higher chloride levels (106 vs. 103, -6 P=4.10 ). Lactate and bicarbonate levels were comparable for both groups. Postop albumin levels were low but not significantly lower in the HES-group (24 vs. 22g/L, P=0.06 ). Derived variables SIDa and SIG were significantly lower in the HES-6 group (40 vs. 34, P<7.10 , -0.38 versus 3.29, P=0.005). SIDe was comparable between groups. Discussion. Low serum albumin (= weak acid) masks acidosis by reducing the anion gap. This acidosis is probably offset by metabolized lactate in the geloplasma group whereas the hyperchloraemic acidosis in the HES-group is still present (SIDa ) in the postoperative phase. A positive SIG suggests the presence of immeasurable anions (e.g. polyanionic gelatin molecules) in the geloplasma group. The extent of this effect cannot be calculated. In contrast HES is uncharged. Conclusion. Despite a mild hyperchloraemic acidosis, 6% HES 130/0.4 is a safe alternative to gelatins as pump prime because acid-base status is clinically not relevantly deranged and still fully interpretable. Reference. 1. Rehm M, Conzen PF, Peter K, et al. [The Stewart Model. “Modern” approach to the interpretation of the acid-base metabolism]. Anaesthesist 2004; 53(4): 347-357. Review. German

FREE ORAL SESSIONS

S7

O-15 Changes in respiratory mechanics following cardiac surgery: prolonged deterioration in tissue mechanics in patients after cardiopulmonary bypass 1

2

2

1

Barna Babik , Gergely Albu , Zoltan Hantos , Mariann Balazs , 1 2 Gabor Bogats , Ferenc Petak 1

Institute of Anaesthesiology and Intensive Therapy, Department of Medical Informatics and Engineering, University of Szeged, Szeged, Hungary 2

Introduction. The pulmonary consequences of cardiopulmonary bypass (CPB) have not been fully characterized. Method. Respiratory system mechanics were measured the day before surgery and for one week thereafter in two groups of patients undergoing cardiac surgery with or without CPB. Input impedance of the total respiratory system (Zrs) was obtained by averaging 15-s recordings during spontaneous breathing between 4 and 26 Hz in patients with (n=16; group CPB) or without (n=19; group OPCAB) extracorporeal circulation. In all patients, the baseline was established the day before surgery, while the changes in Zrs were followed for 7 days after surgery by collecting data twice a day. Airway resistance ( Raw) was estimated by averaging the total resistive component of Zrs between 16 and 26 Hz, while the changes in respiratory elastance were assessed by calculating the area under the reactance curve below the resonant frequency (AX). Results. There was no significant difference in the baseline respiratory mechanical parameters between the two groups of patients. Raw increased significantly in both groups (P=0.04) immediately after extubation (day 1, evening,) with maximal changes of 29.5±13.9% and 58.5±13.1% (P=0.17) in groups CPB and OPCAB, respectively. Raw exhibited a gradual decrease with a complete recovery before discharge. Smaller increases in AX were observed in the OPCAB group (138±38%, day 3) than in the CPB group (217±80%, day 4), and the recovery was faster in the former group. Discussion. These findings suggest that the uniform increases in Raw in both groups of patients may be a consequence of the mechanical irritation in the upper airway exerted by the ET tube. The increases in AX may indicate the development of atelectasis, as a result of mechanical ventilation, prolonged supine position and/or the limitations in postoperative respiratory movements. The greater and longer increases in AX in the CPB patients may be attributed to the compromised production of surfactant by the pneumocyte-II cells, due to the temporary pulmonary ischaemia during CPB. This work is supported by grant OTKA K62403. O-16 Vasopressin deficiency contributes to the vasodilatory syndrome after cardiac surgery 1

1

1

Cedric Bernard , Olivier Attard , Anne Le Barbe , Philippe Gau1 1 1 2 dard , Jacob Eliet , Remy Coves , Gilles Guillon , Pascal 2 Colson 1

SAR D, Hopital Arnaud de Villeneuve, Montpellier, France, IGF, Montpellier, France

2

Introduction. The post-cardiac surgery vasodilatory syndrome (PCSVS) occurs in 10% of patients undergoing cardiopulmonary bypass (CPB) [1]. Vasoplegia is sometimes unresponsive to

norepinephrine and seems then to be related to a vasopressin deficiency [2,3]. The aim of the study was to assess whether a relative vasopressin deficiency contributes to PCSVS even in the absence of refractory hypotension. Method. Consecutive patients over a two months’ period, scheduled for cardiac surgery under CPB were included in the study, except patients suffering from chronic renal failure. Blood samples were obtained from blood withdrawals routinely before CPB (H0), during CPB and after surgery, at postoperative hour 8 (H8) and were used for arginine vasopressin (AVP) measurements using radio-immuno assay. Besides AVP measurement, preoperative characteristics and perioperative data were collected. PCSVS (assessed as hypotension unresponsive to volume replacement therapy and without cardiogenic shock features) was treated with norepinephrine (NE). Patients treated with NE were compared to the others. Statistical tests consisted of variance analysis and non-parametric test (Mann Witney or Wilcoxon). A P value of less than 0.05 (P<0.05) was considered statistically significant. Results. Sixty four patients were included, out of which 10 were treated with NE. AVP was significantly less at H8 but not before (H0), or during CPB in the NE-treated group (Figure). NE-treated patients had a lower preoperative left ventricle EF (45.0±14.9 vs. 55.5±10.5%, P=0.03), longer CPB (123.1±46.4 vs. 200.0±80.7 min, P<0.01) and clamping times (87.7±41.5 vs. 1571±70.2 min, P<0.01), higher incidence of low output syndrome (8/10 vs. 4/54, P<0.05) and longer extubation time (27.5±14.8 vs. 8.0±7.0 hours, P<0.01). Discussion. A relative vasopressin deficiency may contribute to PCSVS that occurs more frequently in high cardiac risk patients undergoing more complex surgery associated with prolonged CPB and aortic cross clamping times. 80,00 NA

CTL

60,00

40,00

* 20,00

0,00 T0

cec

H8

References. 1. Albright T, Zimmerman MA, Seizman CH. Vasopressin in the cardiac surgery intensive care. Am J Crit Care 2002; 11: 326-332. Review 2. Argenziano M, Chen JM, Choudri AF, et al. Management of vasodilator shock after cardiac surgery: identification of predisposing factors and use of a novel pressor agent. J Thorac Cardiovasc Surg 1998; 116: 973-980.

S8

FREE ORAL SESSIONS

Oral III – Echocardiography O-17 A comparison of the echocardiographic and the thermodilution method for measuring cardiac output in a swine model of cardiac arrest Lila Papadimitriou, Eleni Bassiakou, Eleni Koudouna, Theodoros Xanthos University of Athens, Department of Experimental Surgery and Surgical Research, Athens, Greece Introduction. Thermodilution is known to be the gold standard of measuring cardiac output. On the other hand, the echocardiographic method is commonly used in measuring cardiac output during the post-resuscitation phase, since it is easy to perform. The aim of this study was to assess whether the echocardiographic method would be as precise as the thermodilution method in an animal model of ventricular fibrillation. Method. Twelve healthy Landrace Large White piglets, 20 ±1.5 kg aged 16-18 weeks, were involved in this study. Animals were anaesthetized and surgically prepared according to an established model of ventricular fibrillation [1]. Cardiac output was measured by both the thermodilution (T) and the echocardiographic (E) method in two different time-points: (i) 30 min after haemodynamic stabilization (baseline) and (ii) 30 min after the Return Of Spontaneous Circulation (ROSC). Results. Baseline echocardiographic and thermodilution values of cardiac output did not show any statistically significant difference (E: 4.9±0.3 L/min, T: 5.1±0.2 L/min, P>0.05). In contrast, echocardiographic cardiac output was significantly lower than thermodilution cardiac output, 30 min after ROSC (E: 3.2±0.2L/min, T: 2.4±0.5 L/min, P<0.05). Discussion. Cardiac output is considered as one of the most valuable measurements for monitoring the post-resuscitation phase. According to this study, the echocardiographic method is shown to be equally reliable as the thermodilution method of measuring cardiac output in healthy myocardium. When the measurements are performed in a dysfunctional myocardium, the echocardiographic method seems to underestimate the values of cardiac output, when compared to the thermodilution method. Reference. 1. Bassiakou E, Xanthos T, Koudouna E, et al: Atenolol in combination with epinephrine improves the initial outcome of cardiopulmonary resuscitation in a swine model of ventricular fibrillation. Am J Emerg Med 2008; 26(5): 578-584. O-18 Role of transoesophageal echocardiography (TOE) in the multimodal assessment of donor hearts for transplantation 1

Kristof Racz , Nandor Marczin

2

1

Royal Brompton and Harefield NHS Trust, Harefield, Middle2 sex, United Kingdom, Imperial College London, London, United Kingdom Introduction. Donor heart failure remains the leading cause of rejection of potential hearts for transplantation. Most centres have adopted active donor management/assessment protocols that routinely involve transthoracic echocardiography and hormone replacement. However, the role of cardiothoracic anaesthetists and the value of TOE remain controversial. The aim of the study was to review our experience aimed at improving donor management by integrating hormone replacement, inva-

sive haemodynamic assessment and TOE through involvement of a cardiothoracic anaesthetist in the retrieval team. Method. Forty five heart retrievals were attended between October 2007-June 2008. On arrival to the donor hospital, ongoing pharmacological therapy was re-assessed and invasive haemodynamic, TOE monitoring (Vivid i) and goal directed haemodynamic management were instituted. Results. Thirty three donors (73%) received T3 hormone replacement, 30 donors (67%) received vasopressin therapy and 15 donors (33%) was treated with noradrenaline infusion prior to arrival of the retrieval team, which were increased to 45 (100%), 39 (87%) and 16 (36%), respectively, as part of active donor management, yielding 7 accepted hearts (16%). Ejection fraction by TOE correlated weakly with cardiac index by Swan Ganz 2 cartheterization (R =0.26) and was independent of wedge pres2 2 sure (R =0.04) and systemic vascular resistance (R =-0.03). Baseline EF and cardiac index tended to be higher and PCWP and SVR tended to be lower in accepted vs. rejected hearts. Ultimately, global LV dysfunction, severe regional wall motion abnormalities, hypertrophy and structural defects by TOE were among primary reasons for rejecting donor hearts by the surgical team (45, 38, 22 and 12%, respectively). Conclusions. TOE appears a useful complimentary monitoring tool in multimodal assessment of donor hearts with impact on surgical decision making. Cardiothoracic anaesthetists are well suited for integrating multiple information from such extended monitoring and implementing optimal management strategies. Despite this effort, the majority of potential hearts remain unsuitable for transplantation in our region. O-19  method: assessing The diagnostic accuracy of the A-view the distal ascending aorta for atherosclerosis using modified transoesophageal echocardiography 1

2

Bas van Zaane , Arno P. Nierich , George J. Brandon Bravo 2 1 3 Bruinsma , Wolfgang F. Buhre , Peter M.J. Rosseel , Erik E.C. 1 1 de Waal , Karel G.M. Moons 1

2

University Medical Center Utrecht, Utrecht, Netherlands, Isala 3 Clinics, Zwolle, Netherlands, Amphia Hospital, Breda, Netherlands Introduction. Several studies have shown that the use of epiaortic ultrasound scanning (EUS) of the ascending aorta (AA) combined with appropriate modification of operative technique when severe AA atherosclerosis is present, can effectively reduce the incidence of stroke after cardiac surgery. EUS has become the gold standard for detecting AA atherosclerosis, but this method can only be used during the operation. Transoesophageal echocardiography (TOE) is a widely used imaging modality permitting evaluation of the thoracic aorta preoperatively, but assessment of the distal AA is hampered by interposition of the air-filled trachea between oesophagus and AA. Recently it was shown that the A-view (Aortic-view) method, a modification of conventional TOE using a fluid-filled balloon, is able to overcome this limitation. The aim of this study was to quantify the diagnostic accuracy of the A-view method. Method. In a cross-sectional diagnostic study, patients over 65 years of age undergoing cardiac surgery underwent the Aview method and EUS (reference standard). Results. In 345 patients we obtained A-view method and EUS images. The severity of atherosclerosis visualized with the Aview method compared to EUS showed moderate agreement with a weighted Kappa of 0.65 (95%CI 0.53 – 0.77). After di-

FREE ORAL SESSIONS

S9

chotomization the positive predictive value of the A-View® method was 74% (67% - 80%), the negative predictive value 98% (96% - 100%), the sensitivity 97% (94% – 100%), and specificity 80% (74% - 85%). One patient suffered from pulmonary haemorrhage; he recovered without further sequelae. Further clinical significant cardio-pulmonary side effects were not observed. Conclusion. The A-View® method yielded adequate diagnostic accuracy in the detection of AA atherosclerosis without significant cardio-pulmonary side effects as compared to EUS. Therefore, the A-view® method may contribute to guiding surgical strategy in patients undergoing cardiac surgery and eventually reducing the incidence of postoperative stroke. O-20 Real time 3D TOE guided sizing of the annuloplasty ring during mitral valve repair 1

1

2

2

Joerg Ender , Sarah Eibel , Stephan Jacobs , Michael Borger , 4 3 2 Christoph Viola , Michael Gessat , Volkmar Falk , Chirojit Muk1 herjee 1

Department of Anaesthesiology and Intensive Care Medicine II 2 and Department of Cardiac Surgery, Heartcenter, University 3 Leipzig, Leipzig, Germany; Innovation Center for Computer Assisted Surgery, University Leipzig, Leipzig, Germany; 4 TomTec, Munich, Germany Introduction. Mitral valve (MV) annuloplasty is an integral part of MV repair surgery (1). However, controversy exists as to the optimal method of sizing of the MV annulus when implanting an annuloplasty ring. The aim of this study was to investigate the additional value of Real Time 3D transoesophageal echocardiography (RT 3D TOE) for determining optimal annuloplasty size in MV repair. Method. In patients undergoing elective MV repair, a RT 3D TOE examination of the mitral valve was performed using the Zoom- Mode (IE 33, Philips, Netherlands). A modified software based on 4D valve assessment® (TomTec, Munich, Germany) was used to create 3D Computer Aided Design-models (CAD models) of standard annuloplasty rings (28 to 36 mm) which were stored in a digital database. These virtual 3D annuloplasty ring templates were subsequently superimposed on the preoperative RT 3D-TOE examination. of the MV and results were compared to conventional sizing under direct vision. The echocardiographer was blinded to the implanted ring size. Results. Fifty-three patients (14 female, 39 male) were included in the study. The correlation between the selected 3D annuloplasty ring template and the implanted annuloplasty ring size was 0.91. Thirty seven ring templates (70%) were the same size as the implanted annuloplasty ring, 16 templates (30%) differed by ± 2 mm in size. Discussion. Augmented reality enhanced RT 3D TOE for determining optimal annuloplasty ring size during MV repair correlates well with conventional surgical sizing. It is superior to the 3D reconstruction technique and less time consuming (2). A prospective randomized study is necessary to evaluate the clinical value of this new approach. References. 1. Meyer MA, Von Segesser LK, Hurni M et al. Long-term outcome after mitral valve repair: a risk factor analysis. Eur J Cardiothorac Surg 2007; 3: 301-307. 2. Ender J, Koncar-Zeh J, Mukherjee C, Jacobs S, Borger M, Viola C, Gessat M, Fassl J, Mohr FW, Falk V: Value of Augmented Real ity-Enhanced Transesophageal echocardiography (TEE) for Determining Optimal Annuloplasty Ring Size During Mitral Valve Repair. Ann Thorac Surg 2008; 86: 1473-1478.

O-21 Intraoperative transoesophageal echocardiographic evaluation of right ventricular geometry and function in patients undergoing left ventricular assist device implantation Marian Kukucka1, Alexander Stepanenko2, Olaf Bretschneider1, 1 1 3 Alexander Mladenow , Hermann Kuppe , Helmut Habazettl 1

2

Department of Anaesthesiology and Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum Berlin, 3 Berlin, Germany; Institute of Physiology, Charité Campus Benjamin Franklin, Berlin, Germany Introduction. The left ventricular assist device (LVAD) is an effective tool for treatment of patients with end-stage heart failure. However, success can be limited by right ventricular failure (RVF), with subsequently prolonged ICU stay and elevated mortality. Based on geometry and function of the RV estimated by transthoracic echocardiography (TTE) we developed an algorithm for patient selection for LVAD implantation. This study assessed the value of intraoperative transoesophageal echocardiography for further improvement of patient selection. Method. Thirty-seven consecutive patients selected for LVAD implantation with mild or no tricuspid regurgitation and without severe impairment of RV geometry by preoperative TTE were included in our study. The geometry was evaluated in terms of RV end-diastolic diameter (RVEDD), base to apex length of RV and LVEDD. Short/long axis ratio for RV and the ratio between RVEDD and LVEDD were calculated. RV function was assessed by fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE) and strain (deformation) of free RV wall. End-points of our study were RVF and 30-day mortality. Results. All patients were supported by continuous flow pumps. The incidence of RVF was 16% (n =6), the 30-day mortality was 24% (n=9) and RVF was a predictor for 30-day mortality (P=0.022). There was significant difference for RVEDD/LVEDD ratio in RVF group (0.84±0.13 vs. 0.7±0.14 in control group, P=0.02). Cut-off value of 0.72 was predictive for RVF (sensitivity: 0.83, specificity: 0.61, P=0.075). This parameter was significantly different also in 30-day mortality group (0.83±0.11 vs. 0.68±0.13, P=0.004). Cut-off value of 0.77 was predictive for 30day mortality (sensitivity: 0.78, specificity: 0.83, P=0.002). Conclusion. Right to left end-diastolic ratio may be considered as an additional intraoperative predictor of RVF and 30-day mortality in patients after LVAD implantation. O-22 Short term echocardiographic follow up of patients undergoing percutaneous aortic valve replacement

Panagiota Georgiadou1, Dimitrios Tsiapras1, Marina Balanika2, 3 2 Apostolos Thanopoulos , Stauloula Mazen Chouri , 2 1 Lakoumenta , Vasilios Voudris 1

2

2nd Cardiology Department, Anaesthesiology Department, Carciac Surgery Department, Onasis Cardiac Surgery Centre, Athens, Greece 3

Introduction. Percutaneous aortic valve replacement (PAVR) is proposed as an alternative to the classic procedure in patients with a high operative mortality risk. This report describes the short term echocardiographic follow up of patients underwent PAVR. Method. Eleven patients (mean age 78±4 years, mean logistic EuroSCORE 31±12) who underwent PAVR were included in this report. All patients had a thorough transthoracic (TTE) and transoesophageal (TOE) echocardiographic study before the procedure (base), continuous TOE monitoring during the procedure and repeated TTE studies before discharge (post) and 1 month

S10

post PAVR (FU). Left ventricular ejection fraction (LVEF) was calculated from 2D study while Doppler study was used to calculate aortic functional valve area (AVA), aortic max (Max PG) and mean (Mean PG) pressure gradients. Colour Doppler was also used for semi-quantitative assessment of aortic regurgitation. Results. All patients had successful PAVR. In 2 of them an Edwards and in 9 patients a Core Valve apparatus was used. TOE study during the procedure confirmed the correct positioning of the apparatus in 10 while in one a reposition was needed. Mild regurgitation was detected in all patients post-procedure without change during follow-up. No pericardial effusion or mechanical complications were detected throughout the follow-up period. AVA was significantly increased post-procedure without significant change during the 1st month (AVA: base 0.71±0.13, 2 post 1.77±0.23, FU 1.79±0.22 cm , P<0.001). Max PG and Mean PG were accordingly decreased (Max PG: base 87±30, Post 20±6, FU 19±5 mmHg, P<0.001 and Mean PG: base 55±20, Post 11±4, FU 10±3 mmHg, P<0.001). Mean LVEF showed only a marginal improvement (base 0.47±0.13, post 0.50±0.10, FU 0.50±0.11, P=0.08) attributed to increase in 3 patients with depressed systolic function (LVEF from 0.30±10 to 0.38±5). Conclusion. Following PAVR there is a significant improvement in aortic valve haemodynamic profile without any mechanical complications. LVEF seems to increase only in patients with decreased systolic function. O-23

FREE ORAL SESSIONS

Table. Incidence of abnormal relaxation

Patients

Em/Am

TDE

Ea

Ea/Aa

Vp

<1

>200 ms

<8 cm/s

<0.7

<45 cm/s

10/21

17/21

19/21

9/21

7/21

Discussion. Left ventricle diastolic dysfunction is observed early after cardiac surgery, probably related to myocardial ischaemia-reperfusion injury (aortic clamping). In sedated, ventilated and haemodynamically stable patients, DP are not able to predict volume loading responsiveness after cardiac surgery. Moreover, indices of excessive preload are associated with positive response to volume loading in most responders. References. 1. Tousignant CP, Walsh F, Mazer CD. The use of transesophageal echocardiography for preload assessment in critically ill patients. Anesth Analg 2000; 90: 351–355. 2. Lattik R, Couture P, Denault AY, et al. Mitral Doppler indices are superior to two-dimensional echocardiography and hemodynamic variables in predicting responsiveness of cardiac output to a rapid intravenous infusion of colloid. Anesth Analg 2002; 94: 1092–1099. O-24 Use of transoesophageal echocardiography in Germanspeaking cardiac anaesthesia departments: results of a survey 1

2

3

4

Echocardiography-Doppler assessment of left ventricle diastolic function after cardiac surgery

Joerg Ender , Joachim Erb , Uwe Schirmer , Steffen Friese , 4 2 1 Udo Kaisers , Claudia Spies , Mark Wittmann

Géraldine Culas, Jacob Eliet, Philippe Gaudard, Olivier Attard, Anne Le Barbe, Remy Coves, Pascal Colson

1

SAR D, Hopital Arnaud de Villeneuve, Montpellier, France Introduction. Preload optimization is crucial in ICU patients [1]. Echocardiography evaluation of left ventricle diastolic function (mitral inflow Doppler analysis, mitral annular motion) may help to assess left ventricle preload [2]. The study was aimed at evaluating these diastolic parameters (DP) in a series of consecutive patients who have undergone cardiac surgery. Method. Patients having cardiac surgery requiring aortic cross clamping under cardiopulmonary bypass have been included provided they were haemodynamically stable, under sedation and with controlled ventilation within the first 2 post-operative hours. Patients with atrial fibrillation and low left ventricle ejection fraction (EF<40%) were not included. A transthoracic echocardiography-Doppler (TTE) was performed (Vivid I, GE) before and after a leg raising test (45°LRT). Em, Am, E deceleration time (TDE), Ea and Aa, and colour Doppler M-mode imaging, velocity propagation (Vp) have been collected and derived parameters calculated (Em/Ea, Ea/Aa, Em/Vp). LRT effect was assessed on aortic flow VTI (AoVTI); the patient was considered as responder to LRT if AoVTI increased by at least 15%. Statistics consisted of a variance analysis and parametric tests (Student’s test) (P<0.05). Results. Twenty one adult patients have been studied (8 aortic valve replacements, 6 CABG, 4 combined surgery, 2 ascending aorta, 1 IAC). Before LRT, all patients had at least one criterion of abnormal relaxation (table). Seven patients were responders with (AoVTI increase of 25.0±12.6% vs. 2.4±5.3% for non responders, P<0.001). There was no relationship between DP before LRT and AoVTI variation after LRT. Em/Ea>15 and/or Em/Vp>2.5 were observed in 5/7 responders and in 6/14 nonresponders.

Abteilung für Anästhesiologie und Intensivmedizin II, Herzzentrum Leipzig, Universität Leipzig, Leipzig, Germany, 2 Klinik für Anästhesiologie mit Schwerpunkt operative Intensivmedizin, Charite Universitätsmedizin Berlin, Campus Virchow-Klinikum und Campus Charite Mitte, Berlin, Germany, 3 Abteilung Kardioanästhesiologie, Universitätsklinikum Ulm, 4 Ulm, Germany, Klinik und Poliklinik für Anästhesiologie und Intensivtherapie, Universitätsklinikum Leipzig, Leipzig, Germany Introduction. Intraoperative transoesophageal echocardiography (TOE) is of growing interest in cardiac anaesthesia. With this survey we wanted to get an overview of the actual situation. Method. During the 22nd annual scientific meeting of the cardiac anaesthesia work group of the German Society of Anesthesia and Intensive Care Medicine we conducted a Teledialogue (TED)-survey consisting of 17 questions to evaluate the use of TOE during cardiac surgery Results. Forty one of 83 German cardiac anaesthesia departments as well as 5 departments from German speaking neighbouring countries participated. Perioperative TOE is performed by the anaesthesiologist in 63% of the departments. While 30% of departments routinely echo their coronary bypass patients, 67% echo their valve procedure patients. 67% of departments own their own TOE machines. Only 35% of departments have a machine and probe per operating room. In 43% of the departments the TOEs are only performed sometimes or its performance supervised by certified examiners. The anaesthesiologist performing the TOE is also responsible for the anaesthetic in 55% of departments. 17% of departments routinely perform all standard views. Exams are limited by available time in 48% of the departments. On average 5-10 minutes are available for a TOE exam, but most departments report the ability to take more time during difficult situations. Interpretation occurs in 60% of the departments during loop acquisition. A written report is generated in 93% of departments and in 87% these are filed in the patient’s chart. Digital images are stored in 61% of departments but 51% only save abnormal findings. Changes of

FREE ORAL SESSIONS

S11

therapy based on TOE findings are documented in 69% of departments. Discussion. Type and extent of the TOE examination are mostly limited by available time, by presence of equipment and

certified examiners. The authors feel that the available time could be used more efficiently by performing a structured examination. Standard exams published by other specialty societies could serve as a template.

Oral IV – Anaesthetic Technique O-25

O-26

Anaesthesia options for transcatheter aortic valve implantation in high-risk patients with severe aortic stenosis

Haemodynamic effects of Schnider and Marsh pharmacokinetic models for propofol are similar during induction of anaesthesia for cardiac surgery

1

1

1

Reto Basciani , Sebastien Trachsel , Claudia Zobrist , Gabor 1 2 3 1 Erdoes , Stefan Windecker , Thierry Carrel , Balthasar Eberle 1

Department of Anaesthesiology and Pain Medicine, 3 Department of Cardiology, Department of Cardiovascular Surgery, University Hospital Bern, Inselspital, Bern, Switzerland

2

Introduction. Interventional transcatheter aortic valve implantation (TAVI) emerges as an alternative to high surgical risk aortic valve replacement. Although TAVI requires anaesthesia care, information about indications, benefits, risks and limitations of different anaesthetic strategies is scarce. The aim of our survey was to define characteristics of TAVI anaesthesia at our institution. Method. With IRB approval, 77 patients (median age 83 y [4992]; NYHA III&IV: 80%) with severe symptomatic aortic stenosis 2 (AVA 0.58 cm [0.2-1.0]) at high risk for surgical valve replacement (log. EuroSCORE 27±15%, STS score 9±7) underwent TAVI between 08/07 and 01/09. Systems used were CoreValve Revalving (n=51; transfemoral or transsubclavian) or the Edwards-SAPIEN System (transfemoral, n=9; transapical, n= 17). TAVI was performed during general anaesthesia (GA) or local anaesthesia with sedation (LA-MAC: Monitored Anaesthesia Care). Results. Indications for elective GA were series start (n=4), surgical vascular access and TOE (n=10), and pulmonary oedema, preoperative mechanical ventilation, medical disorders, and request (each n=1).

n (%)

Pressors

GA Convers

CPR

Extubated

Mortality

LA- MAC

42 (55)

14 (33) *

3 (8)

4 (10)

39 (93) *

3 (7.1)

GA

35 (45)

35 (100) *

n/a

1 (3)

23 (66) *

1 (2.9)

Total

77 (100)

49 (64)

3 (4)

5 (6.5)

62 (81)

4 (5.2)

CPR=intraprocedural; Mortality=in-hospital; Chi2 test: *P<05.

Discussion. TAVI has good haemodynamic results and a riskadjusted mortality similar to that of surgical AVR. Transfemoral TAVI can be done during LA-MAC in up to 90% of patients. Conversion to GA and/or CPR may be necessary in ≤ 10%. Elective GA is required for transapical TAVI and selected indications. It was associated with more vasopressor and resource use, but no different mortality. Reference. 1. Piazza N, Grube E, Gerckens U, et al. Procedural and 30day outcomes following transcatheter aortic valve implantation using the third generation corevalve revalving system. EuroIntervention 2008; 4(2): 242-249.

João Viterbo, Filipe Vieira, André Lourenço Anaesthesiology Department, Hospital São João, Porto, Portugal Introduction. Haemodynamic stability and smooth induction are cornerstones of cardiac anaesthesia. Schnider’s pharmacokinetic (PK) model was conceived to be better suited to the elderly and obese populations [1]. Our goal was to compare the Schnider and Marsh PK models for propofol during induction of anaesthesia for cardiac surgery. Method. Following collection of relevant medical information, invasive blood pressure (BP), vital signs, and propofol consumption were continuously recorded during induction of anaesthesia for elective cardiac surgery. After a stable effect-site 2.5 ng mL-1 of remifentanil was obtained with Minto’s model, pa-1 tients randomly received 1.5 microg mL effect-site propofol and -1 0.5 microg.mL increments by either the Marsh (M) or Schnider (S) PK models until induction was achieved (bispectral index <50). Sample size was powered (0.8) to detect a 5% difference in mean BP fall with alpha = 0.05. Groups were compared with t-test, chi-squared, and two-way ANOVA. Quantitative variables are mean ± SEM. Results. Forty five patients were enrolled per group. M (57.7 ± 2.3 years old; 84% male; 31% ASA IV) and S (58.1 ± 2.4 years old; 69% male; 27% ASA IV) did not differ in demographic data, surgery type or concurrent diseases. No differences were observed in peak mean BP fall (M: 26.6 ± 1.7 vs. S: 24.1 ± 1.7%, P=0.29) or vasopressor use (P=0.80). Mean BP fall was higher in patients older than 65 years compared with younger patients (28.5 ± 1.9 vs. 23.5 ± 1.5%, P=0.039) irrespective of the PK model. While the propofol requirement per weight was similar, the predicted effect-site concentration (M: 2.31 ± 0.07 vs. S: 2.68 ± 0.09 microg mL-1, P=0.006) and time to induction (M: 296±8 vs. S: 338±13 s, P=0.024) were higher in S compared with M, respectively. Discussion. Although Marsh and Schnider PK models did not differ regarding mean BP fall during anaesthesia induction, predicted effect-site concentration and time to induction were higher with Schnider’s. Reference. 1. Schnider TW, Minto CF, Schafer SL, et al. The influence of age on propofol pharmacodynamics. Anesthesiology 1999; 90: 1502-1516. O-27 The use of continuous monitoring of right ventricular and pulmonary artery diastolic pressures in cardiac surgery Shitalkumar Shah, Giulia Ranaldi, Mark Dougherty, Tommaso Siciliano, Peter Elliott, William McBride Royal Victoria Hospital, Belfast, United Kingdom Introduction. A dedicated catheter to continuously monitor pressure in the right ventricle (RV) at cardiac surgery is not routinely used because of risks of arrhythmias or RV perfora-

S12

FREE ORAL SESSIONS

tion. This problem is overcome by the Quadlumen Trucath ® catheter which is a flow-directed pulmonary artery catheter with lumens for balloon inflation and continuous monitoring of central venous, pulmonary artery (PA) and right ventricular (RV) pressures. We wished to determine how right ventricular diastolic pressures change during cardiac surgery involving cardiopulmonary bypass. Method. Seven patients participated in a prospective ethically approved study using the Quadlumen Trucath catheter to determine how RV pressures change during various stages of cardiac surgery involving cardiopulmonary bypass. In particular we wished to determine how the PA diastolic, RV diastolic and delta (∆) PA diastolic – RV diastolic pressures vary at 4 perioperative set times: (1) prior to anaesthesia induction and (2) (3) and (4) at 30 minutes after induction, protamine administration and arrival in cardiac surgical intensive care unit (CSICU) respectively. Results. The mean values along with standard deviation are presented in Table 1. All values were compared with baseline using Friedman’s and Dunn’s multiple comparisons. Table 1. Mean values +SD for pulmonary artery diastolic (PAD), right ventricular diastolic (RVD) pressures and difference between them (∆ PAD – RVD).

Baseline

30 min post anaesthesia

PAD mmHg

16.8±2.5

RVD mmHg

12.1±1.9

∆ PAD-RVD mmHg

4.7±1.2

30 min post protamine

30 min after arrival to CSICU

15.4±2.4

16.3±3.9

11.7±3.14

11±2

11.3±3.5

8.7±1.6*

4.4±1.3

5±3.5

3±3

O-29 A high-calorie diet improves survival, myocardial function and cachexia in monocrotaline-induced pulmonary hypertension and heart failure in rats

RVD 30 minutes after arrival in CSICU was lower than baseline (*P<0.05).

Discussion. This study demonstrates normal values for ∆ PAD–RVD pressures in routine cardiac surgery where PAD is greater than RVD throughout the study period. Further work is required to determine if deviation from these values will augment existing routinely used methods of diagnosing RV dysfunction [1]. Reference. 1. Zwissler B. Acute right heart failure. Anaesthesist 2000; 49(9): 785-787. O-28 The reliability of continuous mixed venous oxygen saturation monitoring after on-pump cardiac surgery 1

1

2

Matthias Heringlake , Demyan Shpachenko , Matthias Bechtel , 2 1 Thorsten Hanke , Hermann Heinze , Heinrich-Volker 1 1 1 Groesdonk , Klaus-Ulrich Berger , Julika Schön 1

verification of the catheter position and in-vivo calibration according to the instructions of the manufacturer immediately after ICU-admission, 5 to 8 blood samples were taken from the distal port of the PAC for analysis of SvO2 on a standard blood gas analyser (Radiometer, Copenhagen, Denmark) and compared with the SvO2 monitor readings immediately before blood sampling. Data were analysed by Bland-Altman analysis. Results. 180 data pairs were analysed. Bland-Altmann analysis revealed a bias of -0.6% (relative: -0.9%), and limits of agreement of 7.4 to – 9.9% absolute (relative: 11.4 to – 15.1%). Conclusions. In line with recent observations during exercise testing in patients with heart failure, these findings suggests that the Vigilance system for continuous monitoring of SvO 2 gives clinically acceptable results in comparison with intermittent exvivo SvO2 determinations within the first 12h after cardiac surgery. References. 1. Baulig W, Dullenkopf A, Kobler A, et al. Accuracy of continuous central venous oxygen saturation monitoring in patients undergoing cardiac surgery. J Clin Monit Comput 2008; 22: 183-188. 2. Baulig W, Dullenkopf A, Hasenclever P, et al. In vitro evaluation of the CeVOX continuous central venous oxygenation monitoring system. Anaesthesia 2008; 63: 412417. 3. Bendjelid K, Schutz N, Suter PM. [Continuous Svo2 measurements and co-oximetry are not interchangeable immediately after cardiopulmonary bypass. Can J Anaesth 2004; 51: 610-615 – French.

2

Dept. of Anesthesiology, Dept. of Thoracic Vascular and Cardiac Surgery, University of Lübeck, Lübeck, Germany

Introduction. The reliability of continuous monitoring systems for the determination of central (ScvO2) and mixed venous oxygen saturation (SvO2) in patients undergoing cardiac surgery has recently been questioned [1,2,3]. Method. Following approval by the local ethical committee and written informed consent, 31 consecutive patients enrolled for a trial on the effects of different anaesthetics on cognitive function (Eudract-CT-Nr.: 2005-004928-39) were studied within the first 12 hours after on-pump cardiac surgery. All patients were equipped with a pulmonary artery catheter (PAC) for continuous determination of SvO2 connected to a Vigilance II–monitor (Edwards Lifesciences, Irvine, USA). Following pressure guided

1

1

André Lourenço , Francisco Vasques-Nóvoa , Roberto Roncon1 2 1 Albuquerque Jr , João Viterbo , Carmen Brás-Silva , Adelino 1 Leite-Moreira 1

Department of Physiology, Faculty of Medicine, Porto, Portugal, Department of Anaesthesiology, Hospital São João, Porto, Portugal 2

Introduction. One third of severe heart failure (HF) patients are cachectic, 7% of critical postoperative patients develop nosocomial cardiac cachexia (CC), and CC independently worsens HF prognosis [1]. We studied the effects a high-calorie westerntype diet in monocrotaline-induced pulmonary hypertension (PH), HF and marked CC. Method. Male Wistar rats (n=132, 180-200mg) randomly un-1 derwent (i) subcutaneous injection of 60 mg Kg monocrotaline -1 (MCT) or vehicle (Ctrl) and (ii) feeding with either a 5.4 Kcal g , 35% simple carbohydrate (CH) and 35% animal fat, high-calorie -1 diet (HCD), or a 2.9 Kcal g , 60% complex CH and 3% vegetable fat, normal diet (ND). Food intake, weight and mortality were recorded. Metabolism, haemodynamics, morphometry, myocardial apoptosis (terminal dUTP nick end labelling) and standard histology, tumour necrosis factor alpha (TNF) plasma levels, and myocardial expression of TNF, interleukin-6 (IL-6) and endothelin-1 (ET-1) were evaluated at 5 weeks. Groups were compared with Kaplan-Meier survival analysis and simple or repeated measures two-way ANOVA. Variables are mean±SEM. P<0.05 was considered significant. Results. Although both MCT groups presented similar increases in systolic RV pressure, lung medial arteriolar and right ventricular (RV) hypertrophy, compared with Ctrl groups, HCD increased caloric intake, attenuated lean, fat and left ventricular (LV) mass wasting, and total weight loss, improving LV function and survival, compared with ND. HCD also reduced TNF

FREE ORAL SESSIONS

S13

plasma levels and LV histological apoptosis marking and TNF, IL-6 and ET-1 expression in MCT, without inducing insulinresistance. Contrastingly, Ctrl HCD showed insulin resistance, and increased body weight and fat mass, compared with Ctrl ND. Discussion. In addition to antioxidants and early nutritional support and as an alternative to low-calorie regimens, highcalorie diets may improve functional status in the critical and postoperative care of HF and CC. Reference. 1. Meltzer JS, Moitra VK. The nutritional and metabolic support of heart failure in the intensive care unit. Curr Opin Clin Nutr Metab Car. 2008; 11(2): 140-146. Review O-30 The effects of paracetamol, a non-steroidal antiinflammatory drug (diclofenac sodium) and tramadol in the treatment of postoperative pain after cardiac surgery Yasar Arslan, Turkan Coruh, Nihan Yapici, Zuhal Aykac Siyami Ersek Thoracic and Cardiovascular Centre, Istanbul, Turkey Introduction. Postoperative pain management after cardiac surgery has been mainly based on parenteral opioids. However, because opioids have numerous side effects, co-administration of non-opioid analgesics has been introduced as a method of reducing opioid dose [1,2]. In this prospective, randomized, double-blind study, we compared the effects of paracetamol, the non-steroidal antiinflammatory drug diclofenac sodium and tramadol for postoperative analgesia after CABG operations on postoperative pulmonary and haemodynamic parameters, oxygenation and renal and liver functions. Method. After approval of the ethic committee and informed consent 200 patients undergoing CABG operations in elective conditions were selected preoperatively. Preoperative exclusion criteria were renal insufficiency, active peptide ulcer disease, history of gastrointestinal bleeding, age >75 yr, EF <40%, warfarin, dipyridamole or heparin therapy preoperatively, or insulin dependent DM. Patients were randomly and double-blind allocated to receive 75 mg diclofenac (D), tramadol (T), paracetamol (P)(Perfalgan flacon 100 mL, 10 mg/mL-1, Bristol M.S) and placebo (C) postoperatively and drugs were given 30 min before extubation in the intensive care unit (ICU). Standardized anaesthesia was used for all groups. Visual Analogue scores (VAS) were used for pain assessment. The VAS score at rest was st h th th estimated by the patient preoperatively and 1 , 6 , 12 and 24 hour after the drugs. Total arterial blood gases, renal, liver and respiratory function tests were evaluated. MAP, HR, extubation time, ICU stay durations were recorded. Results. The data in the table are mean±SD or number (%)

+

th

12 h VAS

Paracetamol

Placebo

Diclofenac

Tramadol

P

0.42±0.64

6.10±1.69

1.70±0.76

1.78±0.71

0.001**

8.72±2.72

10.45±1.17

7.53±1.77

8.51±2.07

0.001**

20.63±1.92

24.99±0.53

20.31±1.65

20.61±0.92

0.001**

0 (0.0%)

5 (10.0%)

3 (6.0%)

20 (40.0%)

0.001**

+

Extubation time(hr)

+

ICU stay (h)

++

Nausea/ Vomiting

+

One way ANOVA Test;

++

Ki-kare test; ** P<0.01

Discussion. Paracetamol may be used for analgesia management post CABG surgery in selected patients. Paracetamol, diclofenac and tramadol appear to have the same analgesic effects but paracetamol has low side effects postoperatively.

References. 1. Jocelyn Reimer-Kent. Theory to practice: preventing pain after cardiac surgery. Am J Critic Care 2003; 12: 136-143. 2. Lahtinen P, Kokki H, Hendolin H, et al. Propacetamol as adjunctive treatment for postoperative pain ater cardiac surgery. Anesth Analg 2002; 95: 813-819. O-31 Prevention of temperature ‘after drop’ after CABG surgery with normothermic cardiopulmonary bypass using an underbody forced warm-air blanket John Heijmans, Julianka Teodorczyk, Walter van Mook, Dennis Bergmans, Paul Roekaerts Maastricht University Medical Center, Maastricht, Netherlands Introduction. Hypothermia after coronary artery bypass graft (CABG) surgery is associated with adverse outcomes [1,2]. The aim of this investigation was to study whether an underbody forced-air warming blanket could prevent postoperative hypothermia in routine CABG surgery with normothermic cardiopulmonary bypass. Method. After Medical Ethics Committee approval, 60 patients scheduled for elective CABG were assigned into an intervention group (n = 30) who received the active full underbody forced warm air system and a control group who received standard thermal care (n = 30). Normothermic heart-lung machine management was set at core temperature of 36.0ºC. The forced warm air system was set at 43ºC at the end of perfusion until departure from the operating room. Bladder temperature was measured at: T1 – end of perfusion, T2 – departure from the operating room, T3 – arrival in the ICU, T4 – 1 hour after arrival in the ICU and T5 – 3 hours after arrival in the ICU. Results. The number of patients arriving in the ICU with a bladder temperature ≥ 36ºC was significantly higher in the intervention group than in the control group, respectively 27 patients (90%) vs. 14 patients (46.7%) (P<0.001). Initial temperatures (mean ± SD) at T1 were similar in both groups: 36.5ºC ± 0.2ºC vs. 36.7ºC ± 0.3ºC, respectively; P=0.091. On time points T2, T3 and T4, core temperature was significantly lower in the control group as compared to the intervention group, T2: 36.0ºC ± 0.3ºC vs. 36.5ºC ± 0.3ºC, respectively; P<0.001, T3: 35.9ºC ± 0.4ºC vs. 36.2ºC ± 0.3ºC; P<0.001 and T4: 36.0ºC ± 0.6ºC vs. 36.4ºC ± 0.5ºC, P=0.026. At T5, 3 hours after arrival in the ICU, intervention and control groups had similar bladder temperatures (37.3ºC ± 0.6ºC vs. 37.2ºC ± 0.7ºC; P=0.568). The temperature ‘after drop’ from the end of CPB to arrival in the ICU was significantly less in the intervention group compared to the control group (0.4ºC ± 0.3ºC vs. 0.6ºC ± 0.4ºC; P=0.027). Conclusions. This study shows that additional warmth management with a full underbody forced warm air system, applied in the operating room to patients undergoing normothermic coronary artery bypass graft surgery, prevents hypothermia. References. 1. Insler SR, Bakri MH, Sessler DI, et al. An evaluation of a full-access underbody forced-air warming system during near-normothermia on-pump cardiac surgery. Anesth Analg 2008; 106: 746-750. 2. Sessler DI. Complications and treatment of mild hypothermia. Anesthesiology 2001; 95: 531-543.

S14

FREE ORAL SESSIONS

O-32

Patient Details

Audit of fast track cardiac anaesthesia in Northern Ireland Shitalkumar Shah, William McBride, Bharathi Varadarajan Royal Victoria Hospital, Belfast, United Kingdom Introduction. Fast track cardiac surgery was introduced to hasten recovery, reduce the hospital and use resources efficiently [1]. Method. The Patient Administration And Tracking System was used to analyse patients who were extubated within 12 hours after isolated aortic valve replacement (AVR) and coronary artery bypass graft surgery (CABG). We looked into 30 months data from June 2006 that included patients’ demographics, perioperative details and outcomes of extubation. We excluded all high risk patients and those who had resternotomies due to bleeding. Patients were grouped into A and B based on the extubation time as less than 6 hours and 6-12 hours respectively. The data was analysed using Graph Pad Instat 306. Results. No patients were reintubated in group A. Details of 465 patients are presented in the table below. Median ± Standard Deviation and P-values are shown wherever appropriate.

Number of patients Procedure CABG / AVR (%) Order of surgery (am/pm) (%) Elective/Urgent (%) Age in years Male (%) Current smokers (%) Transfer Factor in % Ejection Fraction < 30% (%) Operative Details CPB time (minutes) Clamp time (minutes) Lowest core temp (°C) Outcome Details ICU stay (days) In hospital stay (days)

Group A

Group B

P value

243 86.4 / 13.6 83.5 / 16.5 72 / 28 63 ± 10.4 76.5 6.2 88 ± 19.3 5.3

222 85.6 / 14.4 67.6 / 32.4 70.7 / 29.3 64 ± 8.5 80.2 2.7 85 ± 18.2 3.1

0.89 <0.0001 0.75 0.02 0.36 0.07 0.07 0.35

92 ± 28.7 54 ± 20.8 34 ± 1.8

104 ± 33.3 63 ± 23.8 34 ± 3.1

<0.0001 0.0003 0.001

1 ± 0.2 6±3

1 ± 0.3 7 ± 5.3

0.98 0.0006

Discussion. Operative details and order of surgery significantly prolonged extubation time and hospital stay in this audit and requires further research. Reference. 1. Naughton C, Reilly N, Powroznyk A, et al. Factors determining the duration of tracheal intubation in cardiac surgery: a single-centre sequential patient audit Eur J Anaesthesiol 2003; 20: 225-233.

Oral V – Vascular Anaesthesia O-33 Endovascular repair of traumatic aortic transection: six years of experience 1

1

1

Eleftherios Chalvatzoulis , Pavlos Papoulidis , Olga Ananiadou , 1 1 2 Elias Karfis , Harilaos Koutsogiannidis , Anastasia Apostolidou , 1 1 Angelos Megalopoulos , George Trellopoulos , Konstantinos 2 1 Papadopoulos , George Drossos 1

compared to open surgical management, especially in the setting of patients with multiple injuries. Whereas initial results are encouraging, close long-term follow-up is required until the durability of these devices can be demonstrated definitively.

2

Department of Cardiothoracic Surgery and Department of Cardiothoracic Anaesthesia, ''G. Papanikolaou'' General Hospital, Thessaloniki, Greece Introduction. Endovascular repair of aortic traumatic rupture is proposed as an alternative to open surgical repair, which is associated with high rates of morbidity and mortality, especially in cases with serious co-morbidities. Method. From January 2003 to December 2008, twelve consecutive patients who underwent repair of a traumatic aortic transection with the use of commercially available thoracic stent grafts at a single institution were reviewed. Results. There was a follow-up period of 41.5 ± 22.4 months. All twelve patients are alive, without any complications. Mean patient age was 28.9 ± 8.38 years and all were male. All twelve cases were completed and there were no instances of paraplegia, no procedure related mortality and the 30 day mortality was 0%. Two patients were treated within 48 hours, three within 24 hours and seven within 12 hours of diagnosis. Five patients had an operation prior to endovascular procedure. The mean operative time was 46.5 ± 9.20 min. The blood loses during the procedure were 176.7 ± 127.2 mL. The thoracic aortic grafts were oversized by 12.28% ± 5.32%. Four of twelve cases required complete or partial coverage of the left subclavian artery. A proximal graft collapse occurred in one patient and resulted in acute renal failure and acute pulmonary oedema. It was successfully treated with re-intervention and new in-stent placement. Conclusion. The results of this initial series of patients with traumatic aortic transections treated by endovascular stent graft placement suggest that this approach is safe, effective and can be performed with low rates of morbidity and mortality when

O-34 Fluid management during abdominal aortic aneurysm repair: Hyperhaes vs. Voluven Ilaria Blangetti, Marco Bertora, Carla Avallato, Vladimir Erardi Ospedale Santa Croce e Carle, dipartimento cardiovascolare, Cuneo, Italy Introduction. The use of small volume resuscitation and quick volaemic restoration with small volumes of fluids, dates back to the 1980s although we can consider it as a new practice in patients exposed to significant haemodynamic changes during a surgical procedure [1]. The goal of the study was to evaluate hypertonic iso-oncotic solutions’ effectiveness in fluid management for patients undergoing abdominal aortic aneurysm repair. Method. Sixty eight patients were randomized to Group A: 34 patients, treatment with HyperHAES, HH (HAES 6% 200/0.5 in NaCl 7.2%) and acetated Ringer’s, Group B: 34 patients, treatment with Voluven, HES (HAES 6% 200/0.4 in 0.9% NaCl) and acetated Ringer’s. The Groups were identical for sex, age, BSA, comorbidities and time of clamping. The perioperative fluid replacement was adjusted according to mean arterial blood pressure (MABP) and central venous pressure (CVP). Group A during aortic clamping HH received the infusion (boluses 100 mL, max 4mL/Kg) followed by acetated Ringer’s. Group B during aortic clamping received HES followed by acetated Ringer’s. Anaesthesia was induced with fentanyl, thiopentone and cisatracurium. Maintenance was with desflurane, remifentanil and cisatracurium. Monitoring consisted of ECG, continuous ABP, SpO2, CVP, urine output, cardiac index (CI), central venous saturation (ScvO2). ABP and CI values were measured by a “FloTrac” sensor, CVP and ScvO2 by optical fibre central venous catheter (Vigileo, Edwards Lifesciences). Measurements were made at the following time: T0 (baseline), T1 (after declamping), T2 (end

FREE ORAL SESSIONS

S15

of surgery). MABP, IC, CVP, ScvO2, urine output and lactate. Infused fluids, diuretics, inotropic and vasopressor drugs were registered at T2. Results. Analysing haemodynamic parameter trends (CI, MABP, ScVO2, CVP), we did not find statistically significant differences. Fluid requirement were less in group A (P<0.001) than in group B. Patients treated with HH needed less diuretics (P<0.001) to maintain urine output of about 70-100 mL/h after declamping. (we excluded from statistical analysis patients in need of infrarenal clamping and with a preoperative creatinine clearance <40 mL/min). Lactate trends, more favourable in group A, did not achieve a statistical meaning. Data analysis suggested less use of inotropic and vasopressor drugs in group A. Discussion. The effectiveness of HH in fluid management to achieve the best haemodynamic stability is suggested by less fluid and diuretics requirement, by less use of vasopressor and inotropic drugs and by a more favourable lactate trend, an expression of better tissue perfusion. Reference. 1. Ragaller M, Müller M, Bleyl JU. Hemodynamic effects of hypertonic hydroxyethyl starch 6% solution and isotonic hydroxyethyl starch 6% solution after declamping during abdominal aortic aneurysm repair. Shock 2000; 13: 367-373. O-35 Anaesthesia for emergency surgical pulmonary embolectomy for massive pulmonary embolism 1

1

2

Reto Basciani , Markus Rehsteiner , Alexander Kadner , 1 1 2 Claudia Zobrist , Sebastien Trachsel , Juerg Schmidli , 1 Balthasar Eberle 1

Department of Anaesthesiology and Pain Medicine and Department of Cardiovascular Surgery, University Hospital Bern, Inselspital, Bern, Switzerland 2

Introduction. Emergency surgical pulmonary embolectomy (EPE) in acute massive pulmonary embolism is still considered to be an alternative only if conservative treatment (thrombolysis) is contraindicated or has failed [1]. However, mortality reaches 50% in conservative series [2], but only 10% in EPE patients [3]. After induction of general anaesthesia (GA) for EPE, acute haemodynamic collapse occurs in 19% [3]. The aim of our study was therefore to determine anaesthesia characteristics and risk contribution in EPE in our Institution. Method. With IRB approval, anaesthetic records of 40 consecutive patients (m 24:f 16; median age 60 [22-80] yr) with massive pulmonary embolism who underwent EPE on cardiopulmonary bypass between 02/00 and 12/06 were retrospectively analysed. Patients were referred to EPE directly after diagnosis (n=30) or after medical pre-treatment (e.g. thrombolysis) (n=10). Results. After induction of GA, the incidence of cardiopulmonary resuscitation was 8% (3/39; one patient was undergoing continuous CPR). In addition, for 30% (12/40), a vasopressor infusion became necessary. Overall in-hospital mortality was 5% (2/40). None of the patients who after GA induction required resuscitation (0/4) or became newly vasopressor-dependent (0/12) died during hospitalization. In-hospital mortality was 0% (0/30) if EPE was performed directly after diagnosis, and 20% (2/10) if conservative therapy preceded EPE. Discussion. In EPE, the risk of acute haemodynamic collapse after induction of GA is substantial, but does not significantly influence mortality. Anaesthetic and surgical risk appears to be lower than reported in the literature. EPE can be the primary therapy in massive pulmonary embolism, provided cardiopulmonary bypass can immediately be started after GA induction.

References. 1. Konstantinides S. Clinical practice. Acute pulmonary embolism. N Engl J Med 2008; 359: 2804-2813. Review 2. Kucher N, Rossi E, De Rosa M, et al. Massive pulmonary embolism. Circulation 2006; 113; 577-582. 3. Rosenberger P, Shernan SK, Shekar PS, et al. Acute hemodynamic collapse after induction of general anesthesia for emergent pulmonary embolectomy. Anesth Analg 2006; 102: 1311-1315. O-36 Combined anaesthesia and postoperative epidural analgesia in patients with chronic obstructive pulmonary disease undergoing abdominal aortic aneurysm repair Venetiana Panaretou1, Cryso Loizou1, Konstantinos Filis2, 1 3 2 George Sanidas , Ioannis Papazoglou , Christiana Panaretou , 1 1 Fany Kremastinou , Maria Gouliami 1

2

Department of Anaesthesiology, 1st Department of Propeu3 detic Surgery, Department of Urology, University of Athens Medical School, Hippokratio Hospital of Athens, Athens, Greece Introduction. Patients with chronic obstructive pulmonary disease (COPD) are more likely to develop pulmonary morbidity following major abdominal surgery. The purpose of this study was to examine the efficacy of combined anaesthesia (general and epidural) and that of postoperative epidural analgesia in pain management and in improving postoperative respiratory function. Method. Fifteen patients undergoing elective abdominal aortic aneurysm repair were randomized in two groups: Group A (n=8) received combined anaesthesia and continuous epidural postoperative analgesia. Group B (n=7) received general anaesthesia with intravenous postoperative analgesia. All patients were diagnosed with COPD and inclusion criteria were FEV 1 <80% and FEV1/FVC <0.7. Assessment of variables included intensity of pain with the visual analogue scale (VAS), consumption of analgesics and respiratory function (FVC and FEV 1) preoperatively, during the 1st and 4th postoperative days. Results. There were no significant differences in demographic data between the groups. Postoperative pain scores were higher in group B (P<0.05) and patients in this group received significant higher doses of analgesics (P<0.05). FEV1 was 58.4±11% in group A vs. 60.7±5.9% in Group B preoperatively (P=0.626), 32.6±5.6% vs. 26.7±2.1% (P=0.02) the 1st postoperative day, 50.8±7.6 vs. 40.9±6.2 (P=0.02) the 5th postoperative day. FVC was 65.87±13.6 in group A vs. 65.85±5 in Group B preoperatively (P=0.997), 37.8±7.4 vs. 28.6±2.2 the 1st day (P=0.008) and 52.1±9 vs. 42.6±8.4 the 4th day (P=0.05). Conclusions. Patients receiving combined anaesthesia with postoperative epidural analgesia had less impairment of FVC and FEV1 during the 1st and 4th postoperative days. Combined anaesthesia with postoperative epidural analgesia should be considered in patients with COPD where endovascular treatment could not be performed. Reference. 1. Groeben H. Epidural anesthesia and pulmonary function. J Anesth 2006; 20: 290-299. Review

S16

FREE ORAL SESSIONS

O-37 The effect of combined anaesthesia with epidural postoperative analgesia on splanchnic perfusion in patients undergoing abdominal aortic aneurysm repair 1

1

2

Venetiana Panaretou , Chryso Loizou , Konstantinos Filis , 1 3 2 George Sanidas , Ioannis Papazoglou , Christiana Panaretou , 1 1 Fany Kremastinou , Maria Gouliami 1

2

Department of Anaesthesiology, 1st Department of Propeu3 detic Surgery, Department of Urology, University of Athens Medical School, Hippokratio Hospital of Athens, Athens, Greece Introduction. Patients undergoing major surgery are at risk of developing gut ischaemia and multiple organ failure. The effects of epidural anaesthesia on regional splanchnic blood flow is not well known. The aim of this study was to investigate the effects of combined anaesthesia with epidural postoperative analgesia on splanchnic perfusion. Method. Twenty-one patients undergoing abdominal aortic aneurysm repair were randomized in two groups, a combined (epidural-general) anaesthesia group (EAG n=14) with epidural postoperative analgesia and a control group (COG n=7), general anaesthesia with intravenous postoperative analgesia. After induction of anaesthesia a sigmoid and a gastric tonometer were placed for the measurement of sigmoid and gastric intra-

mucosal CO2 levels (PCO2 sigmoid and PCO2 gastric), the regional-arterial CO2 difference (PrPa sigmoid and PrPa gastric) and the intramucosal pHi. Additional measurements included mean arterial pressure (MAP), cardiac output (CO), systemic vascular resistance (SVR) and arterial lactate levels. All measurements were performed at predetermined time points: after induction of anaesthesia (T0), before aortic clamping (T1), 20 minutes after clamping (T2), 10 minutes after declamping (T3), before tracheal extubation (T4), 2 (T5), 6 (T6),12 (T7) and 24 hours postoperatively (T8). Results. There were no significant intra- and intergroup differences for MAP, CO, SVR. Arterial lactate levels increased in both groups at T1, T2, T3, T4, T5. There were no significant intergroup differences for gastric tonometric values. Sigmoid pHi decreased in both groups at T1, T2 ,T3 with a significant difference between the groups at T1. PrPa sigmoid decreased in both groups at T1, T2 with a significant difference between the groups. PgCO2 sigmoid increased in both groups at T1, T2 and this increase was significantly more in COG. Conclusion. Combined anaesthesia with postoperative epidural analgesia may improve intestinal perfusion. Reference. 1. Piper SN, Boldt J, Schmidt CC, et al: Hemodynamics, intramucosal pH and regulators of circulation during perioperative epidural analgesia. Can J Anaesth 2000; 47(7): 631-637.

Oral VI – Organ Protection O-38 The effect of continuous negative external cuirass ventilation on arterial blood gas measurements in volunteers 1

1

1

Baseline

Continuous negative

Rest 1

Control Mode

Rest 2

pH

7.43± 0.01

7.43± 0.03

7.42± 0.01

7.48± 0.05 *** ^^^

7.43± 0.03♣♣

Po2

13.7± 0.098

13.02± 0.94

12.04± 1.24*

14.22± 1.5♠♠♠

11.76± 1.93^♣♣♣

Pco2

4.7± 0.42

4.76± 0.51

4.98± 0.42

3.8± 0.61***^^^♠♠♠

4.7± 0.46♣♣♣

-0.55± 1.38

-0.29± 1.3

-0.2± 1.2

0.03± 1.29

-0.05± 1.41

1

Giulia Ranaldi , Tommaso Siciliano , Brian Trethowan , Mark 1 1 2 Dougherty , Peter Elliott , Sabino Scolletta , Pierpaolo Gioma2 3 1 relli , David Linton , William McBride 2

Royal Victoria Hospital, Belfast, United Kingdom, Universita' di 3 Siena, Siena, Italy, Hadassah University Hospital, Jerusalem, Israel

Introduction. Negatively applied pressure ventilation to the thorax and abdomen in intubated patients following cardiac ® surgery using the RTX ventilator has favourably altered arterial blood gas measurements [1]. Effects on arterial blood gases of various modes of negative pressure ventilation in healthy volunteers are unknown. With full ethical and institutional approval we ® investigated the hypothesis that the use of the RTX ventilator in continuous negative and control modes will lead to improved oxygenation in healthy volunteers breathing room air. Method. Ten volunteers had continuous radial artery pressure monitoring. Five were active smokers and 5 lifelong nonsmokers. Arterial blood gas samples were obtained before the end of 5 experimental modalities each lasting 5 minutes: (1) baseline; (2) continuous negative of -20 cm H 2O, (3) first rest period; (4) control mode of 12 breaths/min at -20 cm H 2O; (5) second rest period. Results. Control mode improved oxygenation and reduced PCO2 compared with the preceding and ensuing rest periods (see Table 1). These changes were more marked in smokers.

Base excess

Table 1. The table shows arterial blood gas variables (mean ± standard deviation) at each experimental modality for 10 subjects. Repeated measures analysis of variance was used to compare sampling times with (1) baseline (*P<0.05; **P<0.01; ***P<0.001); (2) continuous negative (^^^P<0.001); (3) rest 1 (♠P<0.05, ♠♠♠P<0.001) and (4) control mode (♣♣P<0.01; ♣♣♣ P<0.001). Conclusion. The use of the external cuirass ventilation in control mode in healthy subjects leads to improved oxygenation. Reference. 1. Trethowan B, Elliott P, Varadarajan B, et al. Continuous negative extra thoracic pressure in respiratory complications after cardiac surgery. Br J Anaesth 2008; 101(4): 589P590P.

FREE ORAL SESSIONS

S17

O-39

O-40

The haemodynamic effects of continuous negative external cuirass ventilation in volunteers

Use of the RTX cuirass ventilator® improves cardiac cycle efficiency in extubated cardiac surgery patients

1

1

1

1

1

1

Giula Ranaldi , Mark Dougherty , Tommaso Siciliano , Brian 1 2 2 Trethowan , Sabino Scolletta , Pierpaolo Giomarelli , Salvatore4 1 3 1 Mario Romano , Peter Elliott , David Linton , William McBride

Giulia Ranaldi , Mark Dougherty , Tommaso Siciliano , Peter 1 2 2 Elliott , Sabino Scolletta , Pierpaolo Giomarelli , Brian Tre1 3 1 thowan , David Linton , William McBride

1

Royal Victoria Hospital, Belfast, United Kingdom, Universita' di 3 Siena, Siena, Italy, Hadassah University Hospital, Jerusalem, 4 Israel, Universita' di Firenze, Firenze, Italy

1

Introduction. Negatively applied ventilatory pressure to the thorax and abdomen in intubated patients following cardiac ® surgery using the RTX ventilator has favourably altered haemodynamic parameters using invasive pulmonary artery catheter (PAC) based cardiac output (CO) monitoring. The haemodynamic effects of various modes of negative pressure ventilation in healthy volunteers is unknown due to the problem ® of invasive monitoring. Recently the MOSTCARE PRAM system has allowed continuous monitoring of CO, cardiac index (CI), pulse pressure variation (PPV) and stroke volume variation (SVV) and cardiac cycle efficiency (CCE) from a single radial arterial artery signal. We investigated the hypothesis that use of the RTX ventilator in continuous negative and control modes will lead to improved venous return with consequent reduction in SVV, PPV, HR (heart rate) with an increase in CCE and CO. Method. Ten volunteers had continuous radial artery pressure monitoring with PRAM analysis allowing continuous recording of SVV, PPV, CCE, CO and CI. Haemodynamic measurements over one minute were taken before the end of 5 experimental modalities, each lasting 5 minutes: (1) baseline; (2) continuous negative of -20 cmH2O, (3) rest period; (4) control mode of 12 breaths/min at -20 cmH20; (5) rest period. Results. Continuous negative mode led to significant falls in SVV and PPV and HR. Although HR was reduced in control mode, the falls in SVV and PPV were not quite significant. CCE was not altered in healthy subjects.

Introduction. Cardiac Cycle Efficiency (CCE) can be obtained ® by the MOSTCARE monitor, a pulse contour analysis device using the pressure recording analytical method (PRAM). CCE represents the relationship between the power developed from the heart and that dissipated within the cardiovascular system (ventricular-arterial coupling), where +1 represents the best possible ventricular function and -1 the worst. CCE correlates with pro-B type natriuretic peptide in cardiac surgery patients suggesting its usefulness in monitoring myocardial failure [1]. External negatively applied ventilation through the RTX cuirass R ventilator , improves haemodynamics in intubated cardiac surgery patients [2]. It is unknown if such ventilation improves CCE in postoperative extubated cardiac surgery patients. Method. Six patients had continuous radial artery pressure ® monitoring with MOSTCARE , allowing continuous recording of CCE. CCE measurements over one minute were taken before the end of 5 experimental modalities each lasting 5 minutes: (1) baseline; (2) mode 1: continuous negative of -20 cm H 2O; (3) first rest period; (4) mode 2: control mode of 12 breaths/min at 20 cm H2O; (5) second rest period. Results. CCE was significantly improved in modes 1 and 2 (See Diagram 1). The patients tolerated the cuirass without difficulty.

Baseline

Continuous negative

Rest 1

Control Mode

Rest 2

HR

71.58±5.8

63.59±6.79***

67.28±6.93

65.13±6.6**

68.79±8.10*

CO

6.1±1.5

6.2±1.4

5.8±1.37

5.7±1.22

5.7±1.04

SVV

18.64±4.1

12.2±3.99**

14.99±5.47

14.84±5.68

15.51±4.5

PPV

21.70±8.68

11.47±5.7*

17.04±7.1

14.19±8.61

14.32±6.3

CCE

0.32±0.17

0.45±0.08

0.41±0.06

0.36±0.2

0.22±0.21

2

Royal Victoria Hospital, BELFAST, United Kingdom, Universita 3 di Siena, Siena, Italy, Hadassah University Hospital, Jerualem, Israel

C C E in 6 p o s to p e r a tiv e c a r d ia c s u r g e r y p a tie n ts *

**

0 .5 0

-1< CCE <+1

2

0 .2 5

0 .0 0

- 0 .2 5

Table 1. The table shows the haemodynamic variables at each experimental modality. Repeated measures ANOVA was used to identify significant differences from baseline (*P<0.05; **P<0.01; ***P<0.001). Discussion. A fall in SVV and PPV and HR may suggest improved venous return as a result of the negative intrathoracic pressure. In spontaneously breathing, extubated subjects this device improves haemodynamics. Reference. 1. Scolletta S, Romano SM, Biagioli B, et al. Pressure recording analytical method (PRAM) for measurement of cardiac output during various haemodynamic states. Br J Anaesth 2005; 95(2): 159-165.

baseline

mode 1

rest 1

mode 2

rest 2

Diagram 1. CCE changes throughout the study. Repeated measures ANOVA identified differences from baseline (*P<0.05; ** P<0.01). Conclusion. Negative pressure ventilation improves CCE in extubated cardiac surgery patients and may be helpful following cardiac surgery. References. 1. Scolletta S, Carlucci F, Tabucchi A, et al. Cardiac Cycle Efficiency correlates with pro-B-type natriuretic peptide in cardiac surgery patients. Critical Care 2008; 12: P249. 2. Chaturvedi RK, Zidulka AA, Goldberg P, et al. Use of negative extrathoracic pressure to improve hemodynamics after cardiac surgery. Ann Thorac Surg 2008; 85(4): 1355-1360.

S18

FREE ORAL SESSIONS

O-41 Can ascorbic acid prevent the onset of postoperative atrial fibrillation? 1

1

1

Pavlos Papoulidis , Eleftherios Chalvatzoulis , Olga Ananiadou , 1 1 1 Harilaos Koutsogiannidis , Elias Karfis , Athanasios Madesis , 1 2 2 Theodoros Karaiskos , Vassiliki Tsaprali , Theodora Asteri , 1 Georgios Drossos 1

2

Department of Cardiothoracic Surgery and Department of Cardiothoracic Anaesthesia General Hospital “G. PAPANIKOLAOU”, Thessaloniki, Greece Introduction. Atrial fibrillation (AF) is a relatively common arrhythmia that occurs after cardiac surgery. It is an independent risk factor for death. There is evidence of association between AF and oxidative stress [1]. We supposed that oxidative stress contributes to the mechanism of postoperative AF, so a substance that reduces the free radicals can help to reduce the incidence of postoperative AF. Method. We divided our patients into two groups in a randomized pattern. All patients were about to have coronary artery bypass graft (CABG) surgery and were over 65 years old. We excluded from our study every patient who had AF preoperatively and hyperoxalouria, as well as those having combined valve and CABG surgery. Group A patients did not receive vitamin C. Group B were the patients to whom we administrate vitamin C. Results. A total of 198 patients were included in the study. 125 (group B) received vitamin C and 73 (group A) did not. The incidence of AF was 20-25% in group B and 65-70% in group A (P<0.05). Discussion. The incidence of postoperative AF in cardiac surgery ranged from 10-65% [2]. The incidence is lower for isolated CABG surgery than for valve or for combined valve and CABG surgery. Postoperative AF adds significantly to both the cost and morbidity of cardiac surgery and prolongs the hospitalization. A common factor that induces AF by mechanical, metabolic, or pharmacologic stimuli in the postoperative state may be the redox changes [1]. There is evidence that administration of vitamin C might reduce the incidence of postoperative AF. References. 1. Carnes CA, Chung MK, Nakayama T, et al. Ascorbate attenuates atrial pacing-induced peroxynitrite formation and electrical remodeling and decreases the incidence of postoperative atrial fibrillation. Circ Res 2001; 89: E32–E38. 2. Maisel WH, Rawn JD, Stevenson WG. Atrial fibrillation after cardiac surgery. Ann Intern Med 2001; 135: 1061–1073. Review O-42 Early decrease in procalcitonin is a good marker of successful initial treatment in severe postoperative pneumonia Julien Fendeleur, Anne Le Barbe, Olivier Attard, Julien Sourroque, Philippe Gaudard, Jacob Eliet, Pascal Colson SAR D, Hopital Arnaud de Villeneuve, Montpellier, France Introduction. Procalcitonin (PCT) is an interesting marker of pulmonary infection which is useful for infection diagnosis but also for treatment follow-up [1,2]. The aim of the study was to analyse whether PCT decline reflects infecting agents sensitivity to initial antimicrobial therapy (AT).

Method. Patients with diagnosis of severe pneumonia following major cardiothoracic or vascular surgery were retrospectively included in the study. Severe pneumonia was suspected as a combination of several manifestations including fever, hyperleucocytosis or leucopoenia, new radiological infiltrate, and/or a Clinical Pulmonary Infection Score >6, a PCT >1 ng/mL and PaO2/FiO2 <200 mmHg. Initial AT was chosen according to the guidelines in use in our institution. Microorganism identification from endotracheal aspiration or bronchoalveolar lavage and antibiotic susceptibility testing, allowed classifying patients according to appropriate (aAT) vs. inappropriate initial AT (iAT). PCT was measured daily over 14 days and its kinetics compared between both groups. Statistical test consisted of variance analysis and Wilcoxon test. P<0.05 was considered statistically significant. Results. Twenty eight patients aged 69±9 (66-73), operated on for vascular (n=6), thoracic (n=7), or cardiac surgery (n=15) have been studied over 10 months. Pneumonia occurred within the 1st to 31st postoperative day (median 6.7), with 4 deaths at day 14. Initial AT was appropriate in 75% (21/28) patients. PCT peak was not statistically different between aAT vs. iAT patients (17.7 ±42.2 ng/mL vs. 12.7 ±26.6 respectively) but PCT decrease was significantly steeper and constant in iAT patients (figure). Discussion. Early and constant decrease in PCT plasma concentration seems to be a good marker of sensitivity of the causative infecting agent to the initial AT. Conversely, the result suggests that absence of early decrease in PCT within 2 days may reflect failure of the AT. Figure. PCT decrease (%) from peak value over days

Adapted

Inadapted

100 60 20 -20 -60 -100 1

2

3

4

5

References. 1. Christ-Crain M, Stoltz D, Bingisser R, et al. Procalcitonin guidance of antibiotic therapy in community-acquired pneumonia: a randomized trial. Am J Respir Crit Care Med 2006; 174: 84–93. 2. Nobre1 V, Harbarth S, Graf J-D, et al. Use of procalcitonin to shorten antibiotic treatment duration in septic patients. Am J Respir Crit Care Med 2008; 177: 498–505.

FREE ORAL SESSIONS

S19

Oral VII – Drugs & Fluids O-43 Inflammation and cytochrome P450-dependent drug metabolism in patients with acquired valvular heart disease Valery Nepomniashchikh, Vladimir Lomivorotov, Michail Deryagin, Lubov Kniazkova, Maxim Novikov Academician E. Meshalkin Research Institute of Circulation Pathology, Novosibirsk, Russian Federation Introduction. The evaluation of inflammation intensity and cytochrome P450-dependent monooxygenases of the liver in patients with acquired valvular heart disease (AVHD) after cardiac surgery. Method. Fifty-seven AVHD patients were studied. All patients underwent heart valve replacement under general anaesthesia and cardiopulmonary bypass. The inflammatory process was quantified with C-reactive protein (CRP), α1-antitrypsin (α1-AT), ceruloplasmin (CP) and α2-macroglobulin (α2-МG). Liver monooxygenase function (LMF) was evaluated with Т ½ AP and clearance of antipyrine (Cl АР ). Results. On the first postoperative day an apparent inflammatory response was observed. The CRP and α1-AT level increased by 910% and 26%, CP and α2-МG decreased by 28% and 39%. A considerable slowdown in hepatic metabolism (more than twice) was noticed, Т ½ АР increased by 125%, while CL AP decreased by 57% against the initial data. On the 3rd-4th day after operation CRP and α1-AT exceeded the baseline (+830%; 84%). The CP content increased by 12%, α2-МG augmented to the preoperative data. While studying LMF, it was found out that Т ½ АР decreased by 24% and Cl AP increased by 12% against the background. This testified that microsomal oxidation was markedly enhanced despite a persisting inflamth matory process activity. On the 10-12 day after operation CRP and α1-AT considerably decreased (+307%; +68%), whereas CP increased (+26%) and α2-МG corresponded to the baseline. The AP pharmacokinetics were unchanged and fitted the initial data. The correlation analysis showed a negative relationship of CLAP with CRP and α1-AT (r = -0.37; r = -0.43; P<0.05). Conclusions. In AVHD patients cardiac surgery leads to inflammatory response intensification and LMF slowdown on the th first postoperative day. On the 3rd-4th and 8-12 day after the operation LMF was restored. A reverse relationship between inflammatory parameters and CLAP implied an inhibiting inflammation influence upon LMF. Slowdown of LMF might change the pharmacokinetic response of AVHD patients. O-44 Levosimendan in patients with acute myocardial ischaemia undergoing emergent surgical revascularization 1

2

2

Andreas Lehmann , Arndt Holger Kiessling , Frank Isgro , 1 1 Johannes Lang , Joachim Boldt 1

Department of Anaesthesiology and Intensive Care Medicine, 2 and Department of Cardiac Surgery, Klinikum der Stadt Ludwigshafen, Ludwigshafen, Germany Introduction. Levosimendan is a calcium sensitizing drug with unique properties. It enhances myocardial contractility without increasing intracellular calcium. By activating ATP dependent potassium channels it exerts cardioprotective and vasodilatory effects [1]. Method. A retrospective matched pair analysis was performed in 71 patients undergoing emergency coronary artery bypass

grafting (CABG) for acute myocardial ischaemia with or without cardiogenic shock. 39 patients received levosimendan (bolus -1 -1 6µg/kg; continuous infusion 0.2µg kg min ) in addition to catecholamines while 32 patients were treated with catecholamines only. Results. Predicted mortality by logistic EuroSCORE was 37% (8-90%) in the levosimendan group and 38% (8-90%) in the control group (median, range). Cardiogenic shock was diagnosed in 49% of the levosimendan patients and 56% of the control group patients (P>0.05). Compared to the control group, levosimendan treated patients had fewer intra-aortic balloon pumps inserted (33% levosimendan; 72% control, P<0.05), and were ventilated for a shorter period (39±39h levosimendan; 113±104h control, P<0.05). In this limited number of patients the reduction in mortality at day 30 (26% levosimendan; 44% control, P>0.05) and need for dialysis (15% levosimendan; 34% control, P>0.05) did not reach statistical significance. Length of stay in hospital did not differ (12±17days, levosimendan; 12±17days, control; P>0.05). Conclusion. In a retrospective matched pair analysis of 72 patients undergoing emergency CABG for acute ischaemia, levosimendan reduced morbidity. The reduced morbidity was not translated into a reduced mortality and a shorter length of stay. A prospective randomized trial is urgently warranted to prove the potentially beneficial effects of levosimendan in patients with acute ischaemia undergoing surgical revscularization. Reference. 1. Soeding PE, Royse CF, Wright CE, et al. Inoprotection: the perioperative role of levosimendan. Anaesth Intensive Care 2007; 35: 845-862. O-45 The effects of levosimendan compared with milrinone in cardiac surgery patients Christos Chamos, Theodora Daidou, Elias Delis, Eleftherios Costopoulos, Vasiliki Karameri, Ioannis Kokotsakis, Constantina Romana Evangelismos General Hospital, Athens, Greece Introduction. The aim of the study was to compare the effect of levosimendan (L) with that of milrinone (M) in high risk patients undergoing cardiac surgery. Method. Twenty patients aged 65 ± 7 years, ASA II-III undergoing elective CABG were randomly assigned to receive before initiation of cardiopulmonary bypass (CPB): Group L (n=10) . -1 levosimendan in a single dose of 24 µg kg followed in 10 min -1. -1 by start of infusion of 0.2 µg kg min and Group M (n=10) mil. -1 rinone in a single dose 50 µg kg followed in 10 min by start of -1 -1 infusion of 0.5 µg kg min for 24 hours. When a patient had a . -5. MAP ≤60mmHg and SVR ≤600 dyn s cm a norepinephrine . -1. -1 infusion of 0.1 µg kg min was started. All patients had measured ejection fraction ≤30%, sinus rhythm, cardiac index (CI) 1.6 . -1. -2 ± 0.4 litre min m , mean arterial pressure (MAP) 60-70 mmHg and pulmonary capillary wedge pressure (PCWP) 26 ± 5 mmHg. Haemodynamic parameters were measured by Swan-Ganz catheter and thermodilution (Baxter-Edwards Lab) before starting the infusion of the drug (T0), after 12 and 24 hours of treatment. Statistical analysis was performed by ANOVA for repeated measurements with P<0.05 significant. Results. There were no significant differences in the demographic data. Haemodynamic results are shown in the Table I.

S20

FREE ORAL SESSIONS

T0

T12h

Group L

Group M

Group L

HR

70±10

67±7

MAP

62±6

60±5

1.6±0.34

1.6±0.32

CI PCWP SVR

T24h Group M

Group L

Group M

80±8*

82±9*

80±6*

82±8*

76±9*

78±10*

80±7*

78±10*

3.8±1*

3.6±0.75*

3.3±0.65*

3.4±0.86*

27±6

29±4

12±5*

13±2*

14±3*

15±3*

1615±154

1625±146

847±197*+

957±415*+

1200±610*+

1346±525*+

*P<0.05 in comparison to T0 (M±SD); +P<0.05 between Groups

All patients were weaned from CPB at the first attempt and in . -1 the two groups additional norepinephrine (2-6 µg min ) was infused because of vasodilation, but the total dose and duration of norepinephrine was lower in Group L (P<0.001). Six patients from both groups needed an intra-aortic balloon pump. Postoperative ventilation lasted for 12-72 hours and the mean stay in the ICU was 100 hours. Four patients died due to multiorgan failure after 7-8 days. Conclusions. Levosimendan provides the necessary inotropic support during weaning from CPB and is more efficient than milrinone for treating post CPB low output [1]. Reference. 1. De Hert S, Lorsomradee S, Cromheek S, et al: The effects of levosimendan in cardiac surgery patients with poor left ventricular function. Anesth Analg 2007; 104: 766-773.

0.83±0.28 W at 6 hours (P<0.001); 0.84±0.30 W at 24 hours (P<0.001) and 0.85±0.35 W at 48 hours (P<0.05). PaOP decreased significantly only in the first 6 hours from 19±6 mmHg to 14±4 mmHg (P<0.05). SvO2 improved significantly from 61±11% to 70±6% at 48 hours (P<0.02). LVEF increased from 30±8% to 37±7% at 48 hours (P<0.01). Mean LOS in CICU was 14±10 days. In-hospital mortality was 23.5%. On univariate analysis CPO was associated with in-hospital mortality. There was a significant difference of CPO baseline values between survivors and non-survivors (0.70±0.3 W vs. 0.48±0.2 W, P<0.01). Conclusions. In our patients, addition of levosimendan following ineffective conventional therapy improved significantly the haemodynamic status in patients with LCO after cardiac surgery. CPO could be a prognostic indicator of outcome in patients with LCO. These preliminary results support the use of levosimendan in patients with LCO after cardiac surgery with favourable short-term effects. Reference. 1. Tasouli A, Papadopoulos, Antoniou T, et al: Efficacy and safety of perioperative infusion of levosimendan in patients with compromised cardiac function undergoing open heart surgery: importance of early use. Eur Cardiothorac Surg 2007; 32: 629-663. O-47 Step by step volume management during off-pump coronary artery bypass grafting

O-46 Utilization of levosimendan for low cardiac output after cardiac surgery Daniela Filipescu, Mihail Luchian, Oana Ghenu, Anca Prodea, Alina Calugareanu, Simona Marin, Horatiu Moldovan, Andrei Iosifescu, Ovidiu Chioncel, Luminita Iliuta Prof. C. Iliescu Institute of Cardiovascular Diseases, Bucharest, Romania Introduction. Levosimendan, a novel inodilator drug, has been shown to improve haemodynamic function in patients with acute heart failure. It seems also to improve the cardiac function following open heart surgery [1]. However its efficacy has not been well established. The aim of our study was to assess the haemodynamic effects of levosimendan for postoperative low cardiac output (LCO) after cardiac surgery. Method. Thirty-four patients with LCO following cardiac surgery, admitted into a cardiac intensive care unit (CICU) between May 2005 and November 2008 were included in this observational haemodynamic study. Levosimendan (0.1 microg kg -1 min-1 for 24 hours, without boluses) was added to conventional inotropes and/or intra-aortic balloon pump (IABP) support as soon as the conventional therapy did not result in substantial haemodynamic improvement. Measured parameters were: cardiac output/index (CO/CI), pulmonary artery occlusion pressure (PaOP), left ventricular ejection fraction (LVEF), mixed venous oxygen saturation (SvO2) and cardiac power (CPO). Baseline data were collected before levosimendan administration and the data sets were obtained at 6, 24 and 48 hours. Length of stay (LOS) in CICU and in-hospital mortality were also registered. Data were expressed as mean ± standard deviation (SD). Fisher’s exact test and non-paired t-test were used when appropriate. P<0.05 was considered significant. Results. All patients were on dobutamine and epinephrine. IABP support was used in 26 (76.5%) of cases. The addition of -1 levosimendan significantly improved CI [from 2.10±0.7 L min -2 -1 -2 -1 m to 2.96±0.9 L min m at 6 hours (P<0.001); 2.97±0.7 L min -2 -1 -2 m at 24 hours (P<0.001) and 2.87±0.7 L min m at 48 hours (P<0.05)]. CPO increased significantly from 0.54±0.23 W to

Andrew Yavorovskiy, Irina Tolstova, Boris Akselrod, Armen Bunatian National Research Center of Surgery, Moscow, Russian Federation Introduction. Adequate volume status is one of the cornerstones to prevent haemodynamic disturbances during off-pump coronary artery bypass grafting (OPCAB). The goal of the study was to determine the optimal level of preload to maintain stable haemodynamics during OPCAB. Method. Twenty eight patients scheduled for OPCAB were randomized into 2 groups. In both groups stroke volume index (SVI) and global end-diastolic volume index (GEDI) were assessed using a transpulmonary thermodilution method. Patients of Gp.I (n=14) received standard volume management, based on routine parameters such as HR, MAP, CVP, urine output and visual estimation of the heart. In Gp.II (n=14) passive legsraising test was carried out before the introduction of anaesthesia. This test was used to estimate fluid responsiveness and identify patients who would benefit from fluid loading. Volume challenge was given based on the data received, it was continued up to the moment when the highest possible SVI was reached due to the increase of preload (GEDI). The achieved value of GEDI was considered as a personal optimum and was maintained during surgery. Results. Mean volume of fluid management in Gp.I was 28.1±5.7 mL/kg, in Gp.II – 38.6±6.5 mL/kg (P<0.001). Received haemodynamic data showed that haemodynamics was more stable in Gp.II in comparison with Gp.I. Hypotension during the induction was registered in 6 patients of Gp.I (43%) and only in 2 patients of Gp.II (14%). During surgical manipulation including restraint, compression and displacement of the heart the values of MAP, SVI and GEDI were greater in Gp.II. Cardiotonic agents were required less in Gp.II (21% vs. 50%). The lack of significant differences in recorded clinical data is possibly caused by the small number of patients. Conclusion. During OPCAB, volume management based on the evaluation of personal optimal values of preload resulted in the decrease of episodes of haemodynamic disturbances during

FREE ORAL SESSIONS

S21

surgery and prevented hypervolaemia and excessive haemodilution. O-48 Efficiency of Potassium-Magnesium Asparaginate solution in maintenance of serum magnesium and potassium during coronary artery bypass grafting Nina Trekova, Irina Tolstova, Maria Andrianova, Boris Akselrod National Research Center of Surgery, Moscow, Russian Federation Introduction. Electrolytes disturbances are common in cardiosurgical patients undergoing cardiopulmonary bypass (CPB). Potassium-Magnesium Asparaginate solution (PMA) contains more potassium (P) and magnesium (M) than other crystalloid solutions. The aim of the study was to determine the efficiency of PMA in stabilization of M and P serum concentration during coronary artery surgery. Method. Forty patients scheduled for coronary artery bypass grafting were randomized to receive either the PMA solution 500-1000 mL (Gp.I) or other crystalloid solutions (Gp.II) during surgery. The concentrations of M and P were measured the day before surgery, after induction of anaesthesia (1), before (2) and after CPB (3). Results. The preoperative mean serum P and M concentrations were normal in both groups. The fluctuation of serum P and M levels at different stages of surgery are presented in Table 1. Stage Group

1 I

2 II

I

3 II

I

II

3.5

3.4

4.7

3.6

3.8

3.6

mmol/L

±0.15

±1.4

±0.3∗

±0.02

±0.2

±0.25

mmol/L

Table I

-1

Potassium,

Magnesium,

rhythmias (POA) in relation to glucose homeostasis during open heart surgery with cardiopulmonary bypass. Method. In this prospective, double blind randomized trial 112 non-diabetic patients scheduled for coronary artery bypass grafting received either intravenous magnesium (magnesium group; 2 gm of 50% w/v MgSO4 after induction of anaesthesia and an additional 2 gm in cardioplegia solution, n=56) or equal volume of saline (placebo group; n=56) in a double blinded fashion after approval from the institute ethics committee. The anaesthesia and CPB techniques were standardized to a uniform protocol. Glucose level was determined on-pump on average every 30 minute and electrocardiographic monitoring for arrhythmias was performed for 72 hours after surgery. Boluses of insulin were administered when the glucose level exceeded 200 mg / dL. (Blood sugar ÷100= units of insulin). Arrhythmias sustained for more than 30 seconds, producing haemodynamic disturbance or needing intervention were considered for analysis. The primary outcome study parameter was occurrence of arrhythmia. The incidence of POA was classified into discrete frequency intervals as per the peak blood glucose level and compared with Fisher’s exact test. Results. There was no significant difference in POA among the two groups but subgroup analysis revealed that magnesium effectively attenuated the incidence of POA below a blood glu-1 cose value of 250 mg dL but this beneficial effect of magnesium was lost in Group 3 and 4 patients.

0.77

0.69

1.1

0.72

1.05

0.77

±0.08

±0.07

±0.07∗

±0.09

±0.15

±0.14∗

∗P<0.05 between the groups

In Gp.I the serum M level at the stages of surgery was higher in comparison with Gp.II. It was held at the upper limit of normal throughout the surgery. In Gp.II the mean concentration of serum M was at the lower limit of normal and hypomagnesaemia was registered in 30% of patients. In Gp.I P concentration was maintained mainly by infusion of PMA, whereas in Gp.II it was maintained by additional use of concentrated 4% KCl solution. Conclusion. Infusion of Potassium-Magnesium Asparaginate solution contributes to maintenance of optimal serum magnesium and potassium levels during coronary artery bypass grafting. In addition, no side effects of PMA infusion were observed during the study. O-49

Blood glucose (mg dL )

Occurrence of arrhythmia Magnesium Placebo

P value

100-200(n=31), Group 1

2(18)

7(13)

0.047

201-250(n=25), Group 2

1(12)

7(13)

0.043

251-300(n=33), Group 3

7(16)

5(17)

0.7

> 300(n=21), Group 4

5(8)

6(13)

1.0

Data are presented as: ocurrence (n=number of patients)

Discussion. The results of the present study suggest that increased urinary loss of magnesium; inhibition of vascular Na-KATPase activity [1] and exacerbated acidosis during ischaemia in the presence of hyperglycaemia attenuate the antiarrhythmic property of magnesium therapy. Conclusion. Prebypass magnesium therapy does not reduce POA in the presence of higher blood glucose value. Reference. 1. Gupta S, Chough E, Daley J, et al. Hyperglycemia increases endothelial superoxide that impairs smooth muscle cell Na+-K+-ATPase activity. Am J Physiol Cell Physiol 2002; 282: C560–C566.

Does hyperglycaemia attenuate the anti-arrhythmic property of magnesium therapy in cardiac surgery? O-50 Aloka Samantaray, C Sunil Kumar, Mangu Hanumantha Rao Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, India

Predicting transfusions in cardiac surgery: the easier, the better. The Transfusion Risk and Clinical Knowledge (TRACK) Score Marco Ranucci, Serenella Castelvecchio, Giuseppe Isgrò

Introduction. Hyperglycaemia decreases vascular SodiumPotassium-Adenosine triphosphatase (Na-K-ATPase) activity and contributes to rhythm disturbance [1]. Magnesium, a cofactor to Na-K ATPase, may maintain normal transmembrane sodium and potassium gradients and act as a potential antiarrythmogenic. The study aim was to see the effect of intraoperative magnesium (MgSO4) supplementation on post operative ar-

IRCCS Policlinico S.Donato, San Donato Milanese (Milan), Italy Introduction. Allogeneic blood products transfusions are associated with an increased morbidity and mortality risk in cardiac surgery. At present, a few transfusion risk scores have been proposed for cardiac surgery patients. The present study is

S22

aimed to develop and validate a risk score based on adequate statistical analyses together with a clinical selection of a limited (five) number of preoperative predictors. Method. The development series was comprised of 8,989 consecutive adult patients who have undergone cardiac surgery. Independent predictors of allogeneic blood transfusions were identified. Subsequently, five predictors were extracted as the most clinically relevant, based on the judgement of 30 clinicians dealing with transfusions in cardiac surgery. A predictive score was developed and externally validated on a series of 2,371 patients operated in another Institution. The score was compared to the other existing scores. Results. The following predictors constituted the Transfusion Risk and Clinical Knowledge (TRACK) Score: age >67 years, weight <60 kg for females and <85 kg for males, preoperative haematocrit, gender female, complex surgery. At the external validation, this score demonstrated an acceptable predictive power (area under the curve 0.71) and a good calibration at the

FREE ORAL SESSIONS

Hosmer-Lemeshow test. When compared to the other three existing risk scores, the TRACK score had comparable or better predictive power and calibration. Conclusion. A simple risk model based on 5 predictors only has a similar or better accuracy and calibration in predicting the transfusion rate in cardiac surgery than more complex models. References. 1. Litmathe J, Boeken U, Feindt P, et al: Predictors of homologous blood transfusion for patients undergoing open heart surgery. Thorac Cardiovasc Surg 2003; 51: 17-21. 2. Magovern JA, Sakert T, Benckart DH, et al: A model for predicting transfusion after coronary artery bypass grafting. Ann Thorac Surg 1996; 61: 27-32. 3. Alghamdi AA, Davis A, Brister S, et al: Development and validation of Transfusion Risk Understanding Scoring Tool (TRUST) to stratify cardiac surgery patients according to their blood transfusion needs. Transfusion 2006; 46: 11201112.

Oral VIII – Cerebral Monitoring & Protection O-51 What is the best index of oxygen delivery during congenital heart surgery? Yuko Tomita, Satoshi Kurokawa, Yusuke Seino, Eriko Onuki, Minoru Nomura, Makoto Ozaki Tokyo Women's Medical University, Tokyo, Japan Introduction. Optimal oxygen delivery is crucial for improving outcomes in patients undergoing congenital heart surgery. The purpose of this study was to investigate the change in oxygen extraction during congenital heart surgery using a newly developed central venous oximetric catheter, PediaSat™ (Edwards Lifesciences, Irvine, CA, USA) Method. Twenty-six patients scheduled for congenital heart surgery enrolled in this study were further divided into two groups depending on preoperative arterial saturations - cyanotic (group C) and non-cyanotic (group NC). We monitored continuous superior vena caval oxygen saturation (ScvO 2) with a PediaSat™ catheter and Vigileo™ monitoring system during surgery. Arterial oxygen saturation by pulse oximetry (SpO2) and ScvO2 were measured before incision and before and after sternal closure, and Ω = SpO2 / (SpO2-ScvO2) was calculated. In addition, blood lactate was measured after sternal closure. Statistical analysis was performed with the paired t test, unpaired t test and Mann Whitney U-test. P<0.05 was considered statistically significant. All values are shown as mean ± standard deviation. Results. The range of patients’ age was 9 days – 8 years. 17 patients were non-cyanotic and 15 patients were cyanotic. SpO 2 and ScvO2 before incision were significantly higher in the group NC (99.3 ± 1.0% group NC vs. 83.7 ± 7.6% group C, 78.4 ± 11.6 vs. 65.8 ± 11.9%, respectively). Ω before incision was higher in group NC (6.4 ± 3.8 vs. 5.8 ± 3.1). SpO2 and ScvO2 before and after sternal closure were similar (94.9 ± 7.7 vs. 95.7 ± 6.5%, 73.7 ± 15.1 vs. 73.3 ± 15.8%, respectively). Ω was decreased from 7.3 ± 6.9 to 6.1 ± 3.8 after sternal closure, but the change was not statistically significant. The blood lactate levels were similar in both groups of the patients (2.8 ± 2.6 vs. 3.3 ± 2.5 mmol/L). There was no correlation between Ω and blood lactate level, between ScvO2 and blood lactate level. Conclusions. Ω does not depend on the type of lesion compared to SpO2 and ScvO2. Ω seems to be more sensitive to change of cardiac output than SpO2 and ScvO2. Ω and ScvO2 do not correlate with blood lactate level during surgical repair.

Continuous monitoring of ScvO2 and calculating Ω may be useful for optimization of oxygen delivery in perioperative settings. O-52 The relationship between carotid arterial flow and the left ventricular area is valid to indicate contractility in states of cerebral autoregulation and decreased arterial pressure in sheep 1

2

8

Jens Broscheit , Frank Weidemann , Burkhard Grein , Ralf 1 1 5 3 Muellenbach , Frank Schuster , Aytaç Koca , Christine Lintner , 3 6 4 Ekkehard Kunze , Jörg Brederlau , Paul Steendijk , Norbert 1 7 Roewer , Clemens Greim 1

2

Department of Anesthesiology and Department of Internal Medicine, University Clinics of Würzbrug, Würzburg, Bavaria, 3 Germany; Department of Neurosurgery, Würzburg, Bavaria, 4 Germany, Laboratory of Cardiovascular Research University of 5 Leiden, Leiden, Netherlands, University of Amsterdam, Am6 sterdam, Netherlands, Department of Anesthesiology, Hanau, 7 Hesse, Germany, Department of Anesthesiology, Clinics of 8 Fulda, Fulda, Hesse, Germany, Department of Anesthesiology, University Clinics of Hamburg, Hamburg, Hamburg, Germany Introduction. Myocardial contractility can be estimated by noninvasive ultrasound-derived time-varying elastance (E es). The E´es is composed of flow in the internal carotid artery located close to the middle cerebral arteries where autoregulated cerebral flow can be accurately detected. Furthermore most contractility indices are highly dependent on ventricular load. We therefore investigated whether the index E es is influenced by cerebral autoregulation actuated by decreased arterial pressure which also equals a significant decrease in ventricular load. Method. Time-varying elastance was measured in nine merino sheep using a conductance/micromanometer technique to reveal the standard index Ees, and by the arterial blood-flow velocity–LV area relationship, resulting in the tested index E es. The precision to indicate changes in contractility was estimated by the derived indices Ees and E es. Cerebral microcirculation, systolic myocardial dyssynchrony, tissue oxygen of the brain cortex (p(ti)O2) and cerebral cell damage (L/P ratio) were documented. Following a period of stability, mean arterial pressure (MAP) was decreased to 50 mmHg either by the vasodilator sodium nitroprusside (SNP) or by impaired contractility performed with the cardio selective beta-blocker esmolol. Results. E´es indicated precisely the unchanged myocardial contractility following SNP administration. The index E es was

FREE ORAL SESSIONS

S23

Haemodynamic changes as determinants of jugular bulb desaturation during off-pump coronary artery surgery 1

2

2

Georgia Tsaousi , Antonis Pitsis , Despina Deliaslani , Vasilios 1 1 1 Grosomanidis , Charisios Skourtis , Dimitrios Vasilakos 1

AHEPA University Hospital, Thessaloniki, Greece, Cardiosurgical Institute, Saint Lucas Clinic, Thessaloniki, Greece 2

Introduction. Heart displacement during off-pump coronary artery bypass grafting (OPCAB) may induce deterioration in cardiac function, which endangers global cerebral perfusion and oxygenation. The aim of the study was to examine the impact of haemodynamic alterations during OPCAB procedures on jugular bulb oxygen saturation (SjO2). Method. Thirty consecutive candidates with ejection fraction >40% scheduled for elective OPCAB surgery were recruited. Haemodynamics, mixed venous saturation (SvO2) and SjO2 values were determined on six occasions: anaesthesia induction, anastomosis of 3 main territories, after sternal closure and 6 hours post operation. As regards SjO2 values, two subgroups were identified: desaturated (≤50%) and normal (>50%). Data were analysed by unpaired t-test, logistic regression and ROC analysis. Results. Data (mean±SD) is shown in the table. Parameters

SjO2 ≤ 50%

SjO2 > 50%

(n:17)

(n:163)

CO (L/min)

4.1 ± 0.5

5.3 ± 0.9

0.000

HR (b/min)

79 ± 13

73 ± 13

0.147

mBP (mmHg)

69 ± 8

76 ± 11

0.053

Regional cerebral oxygen saturation (rSO2) during OPCABG by near-infrared spectroscopy by INVOS 4100 Emanuela Venti, Mauro Falco, Emanuele Di Marzio, Federico Candidi, Fabio Pierannunzi, Marco Modestini, Franco Turani European Hospital, Rome, Italy Introduction. Off-pump CABG in comparison to more traditional techniques using CPB may prevent stroke and neurological failure. However few studies investigate the neurological function during OPCABG. The aim of this study was to monitor rSO 2 during OPCABG by near infrared spectroscopy to correlate the changes of cerebral oxygen saturation with the haemodynamic changes. Method. Fifteen patients undergoing OPCABG were enrolled. rSO2 was continuously monitored by near infrared spectroscopy (INVOS 4100; Somanetics Inc., Troy, MI). A Swan-Ganz catheter and a radial artery were used for continuous cardiac output TM TM (CCO) determination by the FloTrac -Vigileo System . rSO2 and CCO data were sampled after induction of anaesthesia (T0), after sternotomy (T1), after positioning of the epicardial stabilizer during the anastomosis of the left anterior descending artery (T2), the left obtuse marginal/diagonal (T3), the anastomosis of the right coronary/posterior descending artery (T4) and after closing the sternum (T5). Results. In the figure are reported the changes of rSO2. At T4 CO decreased to 3.9± 1.2 L/min from 5.1± 1.1 L/min at T0. (P<0.01) 80

**

60

***

2

O-53

O-54

rSO

valid to detect the decrease in contractility induced by esmolol whereas the precision decreased due to an increase in systolic dyssynchrony. Conclusions. Our results suggest that autoregulation of cerebral microperfusion and variations in arterial load will not alter E es measurements. E es is a suitable measurement to use when diagnosing causes of severe hypotension and selecting the appropriate therapy.

40 20

P-value

SV (mL) RAP (mmHg)

54 ± 6

72 ± 16

0.000

16.1 ± 5

11.9 ± 4

0.000

mPAP (mmHg)

26.4 ± 7

22.9 ± 5

0.016

PCWP (mmHg)

19.5 ± 6

16.2 ± 4

0.007

SVR (dyn s cm-5)

1201 ± 263

1057 ± 237

0.034

PVR (dyn s cm-5)

141 ± 59

111 ± 40

0.015

SvO2 (%)

72.2 ± 4

76.7 ± 5

0.003

CO [OR: 4.39 (95%CI: 1.77 - 10.91)] and RAP [OR: 0.84 (95%CI: 0.721- 0.986)] were identified as predisposing factors of SjO2 desaturation, while AUC for CO and RAP regarding SjO2 ≤ 50% was 0.852 and 0.778, respectively. Conclusions. Despite significant haemodynamic derangement during OPCAB procedures, cerebral oxygen balance is rather well-preserved, as evidenced by the limited incidence of jugular bulb desaturation. CO decline and RAP elevation seem to constitute the most powerful determinants of SjO2 deterioration.

T 5

T 4

T 3

T 2

T 1

T 0

0

**P<0.01, ***P<0001 vs. T0. Discussion. rSO2 changes occur during OPCABG. Heart manipulation during anastomosis of the left obtuse marginal/diagonal and right coronary/posterior descending artery may depress haemodynamics and cerebral oxygenation. rSO2 monitoring may be useful in high risk patients submitted to OPCABG. Reference. 1. Marasco SF, Sharwood LN, Abramson MJ. No improvement in neurocognitive outcome after off-pump versus onpump coronary revascularization: a meta-analysis. Eur J Cardiothor Surg 2008; 33: 961-970. Review

S24

FREE ORAL SESSIONS

-1

O-55 Cerebral oximetry alterations during rapid pacing in transfemoral aortic valve replacement 1

2

1

Helena Argiriadou , Kyriakos Anastasiadis , Eva Thomaidou , 1 2 Homiros Chalvatzoulis , George Sarlis , Vasileios Grosomani1 1 2 dis , Liana Drakotou , Christos Papakonstantinou 1

Department of Anesthesia and Intensive Care Unit and Department of Cardiothoracic Surgery, Aristotle University of Thessaloniki, AHEPA Hospital, Thessaloniki, Greece, 546 31 Thessaloniki, Greece 2

Introduction. Near infra-red spectroscopy (NIRS) cerebral oximetry (rSO2) has been reported to identify episodes of cerebral hypoperfusion during cardiac surgery procedures. Rapid pacing (RP) is utilized during trans-femoral implantation of the aortic valve (TAVR) for safer balloon valvuloplasty. The aim of the study was to evaluate the impact of RP in cerebral oximetry during TAVR. Method. Ten patients (7 females / 3 males) with mean age 78.2±3.4 years were scheduled for TAVR (CoreValve) due to severe aortic stenosis. Cerebral oximetry monitoring was applied and data were obtained continuously from both hemispheres (left – L, right – R) during the procedure. Data were electronically recorded in all patients. We analysed the values of cerebral oximetry at specific time points: a) baseline rSO2 – before anaesthesia induction, and b) pacing rSO 2 – during RP (VOO-HR 160 beats/min) and we calculated the percentage (%) fall of rSO2 values. Demographic data, pre-existing neurologic disorder, post procedural neurologic outcome, duration of mechanical ventilation and Intensive Care Unit (ICU) stay were also recorded in all patients. Results. All patients were weaned from mechanical ventilation within 2 hours and were discharged from the ICU within 24 hours post procedure. Neurologic outcome was good for all patients. Cerebral oximetry values during RP were the following base-LrSO2

base-RrSO2

65.4±4.7

66.5±6.5

RP-

RP-

LrSO2

RrSO2

54.7±4.6

57±5.2

% LrSO2

% RrSO2

14.1±5.3

16.8±3.8

rSO2 values promptly recovered immediately after stopping pacing. Discussion. Utilizing RP during balloon deployment in TAVR is a safe practice concerning cerebral oxygenation. Taking into account the advanced age and the possibility of an atheromatous aorta in these patients, the preservation of cerebral perfusion is critical in each step of the procedure. Reference. 1. Hoffman GM. Pro: near-infrared spectroscopy should be used for all cardiopulmonary bypass. J Cardiothorac Vasc Anesth 2006; 20: 606-612. Review

caemia as defined as glycaemia (G) >1.3 g/L (7.1 mmol litre ) after CABG. Method. Two hundred and eight patients undergoing CAGBG surgery during one year were retrospectively included in the study. G was immediately measured after patient admission to the ICU and treated with continuous iv. insulin provided G ex-1 ceeded 7.1 mmol litre . We recognized three groups: diabetic patients (DIAB), non-diabetic patients with reactive hyperglycaemia (REAC) and non-diabetic patients with normoglycaemia (N). Morbidity was assessed by an organ dysfunction score (ODS) from 0 to 5 including cardiac, pulmonary, renal, neurological and haematological dysfunction. The 3 groups were compared using variance analysis and parametric tests. P<0.05 was considered statistically significant. Results. Hyperglycaemia occurred in all diabetic patients (n=63) and in 81% of non-diabetic patients (n=117). Hyperglycaemic patients had an organ dysfunction score significantly higher than normoglycaemics (table). The average length of stay in ICU was also significantly longer (table). There was no significant difference between DIB and REAC groups. Table. N (n=28)

REAC (n=117)

DIAB (n=63)

ODS

0.61±0.79

1.20±1.07*

1.41±1.24*

ICU stay (days)

1.5±0.79

2.42±2.22*

3.67±6.21*

*P<0.01 vs. N Discussion. Hyperglycaemia occurred in most patients and was associated with a higher incidence of organ dysfunction and prolonged ICU stay. Hyperglycaemia reflects insulinresistance which does not correlate to preoperative diabetes but is related to an increased risk of postoperative organ dysfunction [3]. References. 1. van den Berghe G, Wouters P, Weekes F, et al. Intensive insulin therapy in the critically ill patients. N Engl J Med 2001; 345: 1359-1367. 2. Prasad AA, Kline SM, Scholer HG, et al. Clinical and laboratory correlates of excessive and persistent blood glucose elevation during cardiac surgery in nondiabetic patients: a retrospective study. J Cardiothorac Vasc Anesth 2007; 21(6): 843-846. 3. Furnary AP, Gao G, Grunkemeier GL, et al. Continuous insulin infusion reduces mortality in patients with diabetes undergoing coronary artery bypass grafting. J Thorac Cardiovasc Surg 2003; 125(5): 1007-1021. O-57 The neuroprotective effect of magnesium sulphate during brief cardiac arrest

O-56 Incidence and consequences of early hyperglycaemia after CABG surgery

Harald Rinösl, Keso Skhirtladze, Beatrice Birkenberg, Bruno Mora, Barbara Steinlechner, Martin Dworschak

Olivier Attard, Julien Fendeleur, Rémi Coves, Philippe Gaudard, Anne Le Barbe, Brigitte Calvet, Jacob Eliet, Pascal Colson

Medical University of Vienna, Vienna, Austria

SAR D, Hôpital Arnaud de Villeneuve, Montpellier, France Introduction. Hyperglycaemia is associated with several deleterious effects in critically ill patients [1]. Hyperglycaemia is facilitated by postoperative insulin-resistance but its incidence in patients after coronary artery bypass graft surgery (CABG) depends on its definition [2]. The aim of the study was to evaluate the incidence and prognosis of early postoperative hypergly-

Introduction. Magnesium sulphate (MgSO4) is a NMDA antagonist and is capable of stabilizing cell membranes. It has been shown to confer a neuroprotective effect in patients with acute stroke when administered early. We hypothesized that it could thus also have a beneficial effect in cases of iatrogenically induced global brain ischaemia. Method. We therefore investigated 28 patients undergoing elective internal cardioverter/defibrillator (ICD) implantation, which required repeated induction of ventricular fibrillation (VF) for

FREE ORAL SESSIONS

S25

threshold testing. In a double blind fashion, 14 patients randomly received a 16 mmol bolus of MgSO4 30 minutes prior to induction of VF followed by a continuous infusion of 5 mmol over two hours. The 14 control patients received placebo instead. Blood samples to determine neuron-specific enolase (NSE), as a surrogate marker of cerebral injury, were drawn at baseline (i.e. before surgery: NSE1), after wound closure (NSE2), as well as 2, 6 and 24 hours after surgery (NSE3, 4 and 5, respectively). SPSS was used for statistical evaluation. Wilcoxon and Friedman tests were employed to determine differences between and within groups. P<0.05 was considered significant. Results. There were no differences in the demographics of the two groups as well as in the number of applied shocks and the cumulative duration of VF. MgSO4 significantly suppressed postoperative NSE release as long as serum Mg levels were elevated to about twice the normal serum level (NSE2: 10.2 and NSE3: 10.0 µg/L). However, NSE determined six and 24 hours after surgery in the group treated with MgSO4 reached similar levels as in control patients (NSE4: 14.3 and NSE5: 15.4 µg/L; P <0.05 vs. NSE1: 9.8 µg/L). Conclusion. MgSO4 seems to have a temporary neuroprotective effect when administered preemptively. Unfortunately, similar to many other putative pharmacologic neuroprotectants, this beneficial effect appears to disappear as soon as serum Mg levels return to normal. It remains to be determined whether a prolonged application of MgSO4 could permanently suppress neuronal injury. O-58 Cognitive performance after on pump cardiac surgery with intravenous versus volatile anaesthetic regimens 1

1

1

Julika Schön , Lena Husemann , Christian Tiemeyer , Arne 1 1 2 Lüloh , Klaus-Ulrich Berger , Matthias Bechtel , Thorsten 2 1 Hanke , Matthias Heringlake 1

2

Dept. of Anesthesiology and Dept. of Thoracic Vascular and Cardiac Surgery, University of Lübeck, Lübeck, Germany Introduction. Sevoflurane may be protective for the myocardium [1], the kidney [2] and the brain [3] during ischaemia and/or reperfusion. Sparse data are available on the neuroprotective effects of volatile anaesthetics in the clinical setting. The

present study was thus designed to determine differences in cognitive performance after intravenous anaesthesia with propofol/remifentanil versus a sevoflurane/remifentanil-based anaesthesia regimen in patients undergoing cardiac surgery with cardiopulmonary bypass. Method. One hundred and twenty eight patients scheduled for cardiac surgery were randomly assigned to either a total intravenous anaesthetic regimen or to a volatile regimen with sevoflurane given before and after CPB, using intravenous anaesthesia with propofol only during CPB. On the day before surgery and on day 2, 4 and 6 after surgery a set of cognitive function tests and questionnaires including actual emotional state and stress coping was performed by the patients. Demographic, perioperative and surgical data as well as relevant clinical outcome parameters were recorded. Results. The groups did not differ according to demographic variables or type of surgery. The SEVO group had a longer duration of CPB and longer aortic cross-clamp. The groups neither differed according to intra-operative haemodynamics, use of inotropes, fluids and transfusion requirements intraoperatively and on the ICU, nor in the doses of analgesics or sedatives in the postoperative period. There were no differences between the groups in the cognitive function tests in the baseline, as well as 2, and 4 days after surgery. Six days after surgery the SEVO group showed a significantly better performance in the abbreviated mental test, trail-making test and short-time memory test. No differences in self-rated emotional state were seen. Furthermore we found no differences in markers of myocardial damage (Troponin I) or inflammation (leukocytes, Creactive protein). Conclusions. These data suggest that sevoflurane improves neurological outcome after cardiac surgery. References. 1. de Hert SG, Van der Linden PJ. Cardiac protective properties of sevoflurane in patients undergoing coronary surgery with cardiopulmonary bypass are related to the modalities of its administration. Anesth Analg 2004; 99: 311-312. 2. Lee HT, Chen SW, Doetschman TC, et al. Sevoflurane protects against renal ischemia and reperfusion injury in mice via the transforming growth factor-beta 1 pathway. Am J Physiol 2008; 295: F128-136. 3. Payne RS, Akca O, Roewer N, et al. Sevoflurane-induced preconditioning protects against cerebral ischemic neuronal damage in rats. Brain Res 2005; 1034: 147-152.

Oral IX – Intensive Care O-59 Treatment of HIT after cardiac surgery: preliminary experience with fondaparinux Federico Pappalardo, Annamara Scandroglio, Giulia Maj, Annalisa Franco, Mariagrazia Calabrò Department of Cardiothoracic and Vascular Anesthesia and Intensive Care, San Raffaele Hospital, Vita-Salute University, Milan, Italy Introduction. Heparin induced thrombocytopenia (HIT) is an immune mediated prothrombotic disorder. Fondaparinux is a Factor Xa inhibitor via the action of antithrombin but devoid of anti factor II (thrombin) activity. We describe our early experience with fondaparinux in the management of HIT in critically ill patients after cardiac surgery. Method. This retrospective cohort study was conducted on all patients diagnosed with HIT. Dosage of fondaparinux was defined according to creatinine clearance: for Cr Cl >60mL/min, 7.5mg/24h, Cr Cl between 30 and 60 mL/min, 5mg/24h, Cr Cl <30 mL/min, 2.5mg/24h.

Results. In the study period 18 patients were diagnosed as having HIT (1.4% of the overall cardiac surgical population): 11 of them received fondaparinux. Patients in the study group had a nadir platelet count at the time of diagnosis between 8 and 9 -1 72x10 litre ; the time lag from surgery was 6-40 days. All of them had a prompt rise of platelet count and decrease of HIT. Duration of treatment was 4-17 days. During fondaparinux therapy three episodes of major bleeding (defined as life or organ threatening, requiring surgery or >3U of PRBC) were noted. They occurred in three patients with Cr Cl <30mL/min after low risk procedures. Discussion. Because patients with HIT are at increased risk for thrombosis, anticoagulation is warranted. The synthetic pentasaccharide fondaparinux binds to antithrombin and potentiates its inhibition of factor Xa. Patients with renal failure have an increased risk of both thrombotic and bleeding complications. However, a number of antithrombotic drugs undergo renal clearance. Therefore, estimation of renal function is necessary when prescribing these drugs to patients with renal dysfunction. Fondaparinux provides an adjunctive tool in the armamentarium for anticoagulation in postoperative patients with HIT. Caution is advised in patients with poor renal function, especially if fore-

S26

FREE ORAL SESSIONS

seeing invasive procedures. Anti Xa activity monitoring is warranted in these patients and surgery should be delayed at least 36h after the last administration of fondaparinux. O-60 Prone position improves functional residual capacity (FRC) and oxygenation in ARDS after cardiac surgery Riccardo Barchetta, Mauro Falco, Valerio Nicoletti, Cristina Alessandrini, Andrea Salica, Franco Turani European Hospital, Rome, Italy

Method. At a University Hospital, a retrospective study of consecutive patients undergoing cardiac surgery was conducted, using a computerized database based on the West Danish Heart Registry. Data collection was performed prospectively. Patients requiring preoperative dialysis were excluded, leaving a total of 3587 patients (98.6% of original patient cohort). Results. The incidence of ARF-D was 3.2% (n=115). Logistic regression analysis revealed re-operation, perioperative use of aminoglycosides, use of inotropes during anaesthesia, increased general risk profile (EuroSCORE), increased cardiac risk profile (EuroSCORE) and agescore (EuroSCORE) as independent predictors of ARF-D. Table 1.

Introduction. Prone position (PP) can improve oxygenation in ARDS after cardiac surgery, but few studies investigate whether improvement of FRC and lung recruitment occur during PP [1]. The aim of this study was to evaluate the FRC by a modified nitrogen multiple washout technique (NMBW) in ARDS patients after cardiac surgery and to evaluate whether FRC improves during PP. Method. Ten patients with ARDS post cardiac surgery were enrolled in the study. All patients were ventilated in PCV with an Engstrom carestation ventilator (GE Health care) in accordance with the ARDS net guidelines. FRC measurement was carried out with the COVX module integrated within the ventilator (GE Healthcare, Helsinky, Finland) by a NMBW technique. Every patient had a basal FRC and arterial blood gas measurements during supine ventilation (T0) and then 3 hour after PP (T1). All data are reported as mean± SD. A T Test was used to compare changes during the time. Results. Table shows the main results of the study. Parameters FRC mL PaO2/FiO2 PaCO2 mmHg

T0

T1

P

1805±205

2266±227

0.022

126±46

244±57

0.003

48±6

42±8

0.05

Conclusions. FRC measurement by NMBW technique integrated in the ventilator is useful to assess, at the bedside, functional lung impairment in ARDS post cardiac surgery. PP ventilation improves oxygenation by effective lung recruitment with increase of FRC. Reference. 1. Maillet JM, Thierry S, Brodaty B. Prone positioning and acute respiratory distress syndrome after cardiac surgery: a feasibility study. J Cardiothorac Vasc Anesth 2008; 22: 414-417. O-61 Aminoglycosides: a predictor of dialysis-dependent acute renal failure in cardiac surgery Dorthe Nielsen, Carl-Johan Jakobsen Aarhus University Hospital, Skejby, Aarhus, Denmark Introduction. Acute renal failure requiring dialysis (ARF-D) develops in 1-3% of patients after cardiac surgery. Several predictors of ARF-D after cardiac surgery have been identified [1]. The independent risk of ARF-D associated with aminoglycoside treatment perioperatively in cardiac surgery remains uncertain. The aim was to estimate the independent risk of ARF-D, when gentamycin is used in cardiac surgery patients.

Factor Re-operation Perioperative gentamycin Inotropes during anaesthesia Increased general risk profile Increased cardiac risk profile Increased age-score

Odds Ratio 3.42 2.66 2.23 1.26 1.18 1.24

95% CI

P-value

1.83-6.35 1.06-6.66 1.48-3.34 1.11-1.42 1.03-1.35 1.06-1.45

<0.001 0..03 <0.001 <0.001 0.01 0.003

Although postoperative dialysis in general was associated with higher 30-day mortality we could not demonstrate an independent effect of gentamycin on mortality by regression analysis. Conclusion. The identified risk factors of ARF-D align with previous studies. Results show independent detrimental effect of gentamycin in cardiac surgery patients, taking into account factors demonstrating haemodynamic instability. Reference. 1. Filsoufi F, Rahmanian PB, Castillo JG, et al. Prediction and early and late outcomes of dialysis-dependent patients in contemporary cardiac surgery. J Cardiothorac Vasc Anesth 2008; 22: 522-529. O-62 An ICU discharge model for research and logistic purposes indicated that cardiac patients were eligible for discharge earlier than the actual discharge Anne E Vester, Alice Lundbøl Vestergaard, Carl-Johan Jakobsen Aarhus University Hospital, Skejby, Aarhus, Denmark Introduction. The purpose was to create an objective and reproducible ICU discharge model for use in research and as an administrative logistic tool. Method. This was a prospective observational study at a University Hospital. One hundred and thirteen consecutive cardiac patients participated in a 50-day period. Patients were observed and scored in the cardiac recovery unit (CRU) each hour after extubation with no interventions. A discharge model consisting of 5 semi-objective and 7 objective variables were used. Patients were considered eligible for discharge reaching a steady score ≤ 4 (max 40). Results. The score was reached significantly earlier than the actual discharge time (8.7, range 2.9-22.4 hours). No correlation was found between eligible discharge time and ventilation time. Regression analysis showed great differences in factors influencing actual discharge and eligible discharge. Table 1. All values are Mean, in hours Ventilation time Time first score ≤4 after extubation Time steady score ≤4 after extubation Total time to first score ≤ 4 Total time to steady score ≤ 4 Total time to steady score ≤ 4 no single ≥ 3 Actual length of stay in ICU

5.5 4.1 7.4 9.1 12.3 12.7 21.4

FREE ORAL SESSIONS

Conclusion. Although patients are discharged relatively early from our cardiac recovery unit, we found when using objective variables, that patients was eligible for discharge 8.7 hours earlier. The perplexity of definitions in relation to LOS in ICU calls for an evaluation protocol and the described objective discharge model might be valuable, especially with respect to research, but also for logistic and administrative purposes. The relative objectivity makes comparison between units and centres more reliable than present reporting. O-63 Long-term follow-up after tracheostomy during cardiothoracic intensive care Kirstin Wilkinson, Kausalya Raman, David Smith Wessex Cardiothoracic Centre, Southampton, United Kingdom Introduction. Percutaneous dilational tracheostomy (PDT) was introduced on our cardiothoracic ICU in February 1994, trebling our annual tracheostomy rate. All patients who subsequently had a tracheostomy are entered prospectively into a database for subsequent follow-up and audit. We have looked at the fiveyear survival of patients who received a tracheostomy during the first ten years of our experience, and the impact of timing of tracheostomy on the duration of ICU stay [1]. Method. In August 2008 we interrogated the hospital electronic record of each patient who had a tracheostomy between 1 January 1994 and 31 December 2003 to determine whether the patient was dead or alive, and the date of death. We also looked

S27

at the impact of timing of tracheostomy on duration of ITU stay in those patients who had their tracheostomy in the last two years of this cohort. Results. We performed 371 tracheostomies, of which 341 were PDT and 30 were surgical. The average age of the patients was 66.2 yr, with no upward or downward trend over time. Tracheostomy was performed a median of 8 days (range 0-90) after admission to the unit. Overall, 42.3% of patients were still alive at five years, and 36.6% died within 3 months of tracheostomy. 79 patients had a tracheostomy in the last two years of this cohort, a median of 7 days (range 0-27 days) after admission. Those patients who had their tracheostomy within 7 days of admission were discharged from ICU a median of 11.5 days (range 1-50) later and decannulated a median of 16 days (range 1-134) following tracheostomy, while those who had their tracheostomy more than 7 days after admission were discharged a median of 15 days (range 5-63) days later and decannulated a median of 18 days (range 4-60) following tracheostomy. Discussion. This sub-set of patients represents the sickest end of the spectrum of patients in cardiothoracic intensive care. Performing tracheostomy early in this group of patients does not decrease the duration of ICU stay or time to decannulation, unlike the general ICU population. These data may help when planning care and discussing long-term prognosis with the relatives. Reference. 1. Griffiths J, Barber VS, Morgan L, et al. Systematic review and meta-analysis of studies of the timing of tracheostomy in adult patients undergoing artificial ventilation. BMJ 2005; 330: 1243-1246. Review

Oral X – Thoracic Anaesthesia O-64 Ventilation technique in patients with bilateral lung echinococcosis undergoing one-stage surgery Yergali Miyerbekov, Mukhtar Batyrhanov, Vladimir Mutagirov National Scientific Centre of Surgery, Almaty, Kazakhstan Introduction. Patients with bilateral lung echinococcosis operated sequentially on both lungs at surgery is a serious problem for anaesthesiologist because of the high risk of burst of hydatids. The study was designed for improvement of respiratory support of patients with bilaterial lung echinococcosis. Method. Sixty four patients (pts) underwent one-stage surgery for bilateral lung echinococcosis. We developed a mode of respiratory support by using a two-lumen tube. The operated lung was ventilated with small volumes (3-5 mL/kg) to lower peak pulmonary pressure below 10 cm H2O, and the not-operated lung was ventilated by high-frequency ventilation (100 cycles per minute). Blood gases, central and lung haemodynamics, mechanics of ventilation were studied. Stages of study were: 1 – stable anaesthesia; 2 – lateral position; 3 – main stage; 4 – end of operation. Data are presented as mean± . Results. No complications were observed in pts during anaesthesia and surgery. The combined ventilation mode provided adequate gas exchange, with minimal influence on central and lung haemodynamics, and mechanics of ventilation (table).

Parameters

Stage 1

Stage 2

Stage 3

Stage 4

Р aО 2 (mmHg) 358.9±79.6 358±3.7 328.1±50.5 339.4±35.9 Р aСО 2 (mmHg) 40.5 ±7.4 36.6±3.7* 37.9±3.9 38.9±4.3 PCWP (mmHg) 8.1 ±2.0 8.6±1.5 9.3±1.3* 8.8±1.5 QS/QT (%) 13.7±3.2 13.3±2.8 14.5±2.5 14.1 ±7.2 -1 2 CI (l min m ) 3.7±0.4 4.1±0.5* 3.8±0.3* 3.2 ±0.3 43.5±11.9 43.9±9.0 39.6±9.3 45.8±11.7 C (ml/cmH2O) R (cmH2O·l/s) 6.1±1.8* 5.7± 1.9 6.1± 1.6∗ 6.8±1.9 * PCWP – pulmonary capillary wedge pressure; QS/QT – right to left shunt; CI – cardiac index; C – compliance; R – bronchial resistance; * P<0.05 vs. stage 1; P<0.05 vs. stage 2; P<0.05 vs. stage 3

Discussion. The developed ventilation mode reliably isolates lungs from pathological contents, provides adequate gas exchange, does not raise peak airways pressure, does not depress central and lung haemodynamics or mechanics of ventilation and provides comfortable conditions for the surgeon. O-65 Anaesthetic sparing effect in major thoracic surgery: epidural versus paravertebral block Emanuele Piraccini, Vanni Agnoletti, Mikela Berger, Stefano Maitan, Giorgio Gambale Morgagni Pierantoni Hospital, Forlì, Italy Introduction. Neuraxial anaesthesia has been shown to reduce the dose requirements for sedatives. To our knowledge there are no studies in the literature comparing nociception control obtained by epidural local anaesthetic with paravertebral block (PVB). We therefore evaluated the differences in propofol con-

S28

sumption for general anaesthesia accompanied by either epidural anaesthesia or PVB while maintaining the same depth of anaesthesia as measured by Bispectal Index (BIS) and an adequate level of intraoperative nociception control during major thoracic surgery. Method. Twelve patients scheduled for thoracic surgery and general anaesthesia were randomized and submitted to paravertebral block (PB group, 6 patients) or epidural anaesthesia (EA group, 6 patients). Propofol administration was titrated to provide a BIS of 50 (range 40-60). Intraoperative antinociceptive effects were obtained with a PVB performed from T3 to T7 level with ropivacaine (100 mg in 20 mL of saline solution) in PB group, or with ropivacaine 0.2% continuous infusion (5-10 mL/h) via epidural catheter in EA group. An increase of ropivacaine infusion rate was allowed in the EA group in response to evidence of inadequate nociception control based on clinical signs and haemodynamic parameters while i.v. sufentanil boluses were allowed in the PB group as required. In all -1 -1 patients propofol infusion rate (mg kg min ) and BIS were recorded every 15 minutes. Demographic data and surgical time were similar among groups. There were no clinical signs of inadequate nociception control during surgery. Data are presented as mean ± standard deviation; P<0.05 was considered statistically significant. A Student’s t-test analysis was performed to compare mean propofol infusion rate values, while a general linear model for repeated measures was performed to compare BIS values. Results. Mean propofol infusion rate value was 0.08±0.02 in PB versus 0.10±0.03 in EA (P=02). Intraoperative BIS was not statistically different in PB and EA groups (49±13 vs. 48±11 respectively). At the same depth of anaesthesia, intraoperative nociception control obtained with PVB reduced propofol requirements by 20% compared to epidural ropivacaine administration, but this difference is not statistically significant. Discussion. The evidence that inadequate intraoperative nociception control is conducive to major sedatives requirement is a well known issue. This trial does not confirm the anaesthetic sparing effect of epidural analgesia if compared to paravertebral block in major thoracic surgery. However further studies are needed to confirm this data. O-66 Comparative study of intercostal nerve blockade with ropivacaine for post-thoracotomy analgesia Christina Balaka, Artemis Polyzoi, Urania Galanopoulou, Vasiliki Dimopoulou, Antonios Roussakis*, Constantina Romana Department of Anaesthesiology and *Thoracic Surgery Evangelismos General Hospital, Athens, Greece Introduction. Intercostal nerve blockade has been of increasing interest through the recent years as a possible alternative or supplement of epidural analgesia [1]. The present study was designed to evaluate the efficacy of bolus doses of ropivacaine compared to continuous infusion of the same drug on postthoracotomy pain control. Method. Thirty-six male patients, aged 45-70, ASA physical status II–III, were subjected to a posterolateral thoracotomy. All patients were included in this double-blind, randomized study after written informed consent was obtained. Just before the chest closure and under direct vision, a 16G catheter was inserted adjacent to the intercostal nerve bundle. Patients were divided randomly in two groups. Group I (n=18) was scheduled to receive 0.308% ropivacaine at a standard rate of 2 mL/h, whereas Group II (n=18) received bolus doses of 16 mL 0.308% ropivacaine every 8 hours (the same total dose in 8h for both groups). In group I a pump was used for the continuous infusion in order to administer its content at the preset rate. Induction

FREE ORAL SESSIONS

and maintenance of anaesthesia was performed following the same anaesthetic scheme in all patients and i.v. morphine was given at a standard dose 20 min before chest closure. Additional doses of pethidine were administrated during the first 48h postoperatively when needed. The catheter was removed 48h after surgery. Postoperative pain was evaluated using a Visual Analog Scale (VAS 0-10) every 6 hours. Heart rate, blood pressure, first request for pethidine as well as total pethidine consumption were recorded. ANOVA for repeated measures was performed, whereas probability P<0.05 was considered significant. Results. The 2 groups demonstrated similar demographic characteristics, heart rate and blood pressure. First analgesic requirement was recorded earlier in group II, where additional doses of pethidine were higher (P<0.05). The level of pain exceeded 6/10 in most patients of group II before the scheduled bolus dose of ropivacaine. This is a significant difference compared to group I (P<0.5), where most patients kept their pain score under 4/10 throughout most of their 48h surveillance. Discussion. With the advent of a less toxic local anaesthetic such as ropivacaine, intercostal nerve blockade becomes much safer [2]. Continuous infusion of ropivacaine seems to be superior to bolus doses, providing a more adequate state of analgesia for the patients. References. 1. De Cosmo G, Aceto P, Qualtieri E, et al: Analgesia in thoracic surgery: review. Minerva Anestesiol 2008; 74: [Epub] 2. Kruger M, Sandler AM. Post-thoracotomy pain control. Curr Opin Anaesthesiol 1999; 12(1): 55-58. O-67 Health related quality of life after sympathectomy for refractory angina pectoris Miloš Dobiáš, Rudolf Demeš, Jitka Fricová, Martin Stríteský General University Hospital, Prague, Czech Republic Introduction. Refractory angina pectoris is a clinical diagnosis which is characterized by chronic angina due to coronary artery insufficiency in patients who are refractory to conventional forms of treatment. Severe refractory angina has been associated with very impaired quality of life. For assessing health related quality of life (HRQoL) before and after sympathectomy the questionnaire Short Form-36 (SF-36) was used. The SF-36 is a comprehensive, well-established, and psychometrically strong instrument designed to capture multiple operational indicators of functional status, including behavioural function and dysfunction, distress and well-being, and self-evaluations of general health status. Eight subscales are used to represent widely measured concepts of overall quality of life. Method. Seventeen patients underwent video-thoracoscopic sympathectomy (VTSY) between 1998 and 2008 at our institution. We evaluated visual analogue scale (VAS) of pain, angina pectoris (AP) and health-related quality of life (questionnaire SF36) before and after (average 18 months) sympathectomy for refractory angina pectoris. Results. Our results showed that pain decreased on average from level 10 to 4.5 according to the VAS as well as angina pectoris from 4 to 2.2 (CCS). The use of short-acting nitrates was lowered. All eight items of the questionnaire SF-36 were improved. Discussion. This article presents results from a study of followup of patients after VTSY for refractory angina pectoris including objective and subjective health component. VTSY were associated with symptomatic relief of angina and the improvement in the health related quality of life. This study was supported by grant GAČ R 305/08/1164

FREE ORAL SESSIONS

S29

O-68 Morphine free thoracic postoperative analgesia. Is it worthwhile for cancer patients? 1

1

1

Michael Vassiliadis , Maria Markala , Maria Ditsa , Nikolaos 1 1 2 Barbetakis , Ourania Dioritou , Maria Kotoula , Maria Tzou2 veleki-Myronidou 1

2

Theagenio Anticancer Hospital, Thessaloniki, Greece, Aristotle University, Thessaloniki, Greece

Introduction. Opioids, especially morphine, are particularly immuno-depressant agents. The aim of this randomized pilot study was to estimate the influence of morphine in blood levels + of lymphocytes (CD8 , CD56) in thoracic cancer patients and its possible clinical significance. Method. Twenty-four surgical patients with non-microcytic lung cancer, undergoing segmentectomy or lobectomy, were randomized preoperatively in two groups. Group A (n=11) was treated postoperatively with ropivacaine/clonidine epidurally and parecoxib i.v. Group B (n=13) was treated only with epidural morphine. All patients' analgesic dosages were titrated with VAS-guided protocols. Patients with metastatic disease or under chemotherapy, immunotherapy or cortisol were excluded. Two

blood samples (cells/µL) were collected: preoperatively and on the fifth postoperative day. Patients were followed-up after 6 months for disease evaluation. Levels of lymphocytes were compared, using the area-under-the-curve (AUC) method. Two2 sample t-test and x test were used (Instat 3). Results. There was a significant difference between groups * ^ ( P=0.0423, P=0.03). No statistical difference regarding the effect on the disease spread was found. Mean values of AUC (plus standard deviation and 95% confidence interval) and number of patients with metastatic disease after 6 months (Patients meta 6mo) are reported in the following table AUC CD8

+

AUC CD56

Mean±SD

95% CI

Mean±SD

95% CI

Metastases 6 months

*

344-516

364±106

^

293-436

1

234-395

276±69

234-318

2

A (n=11)

430±128

B (n=13)

314.6±132

Conclusions. Thoracic surgical patients who had been treated solely with morphine had greater lymphocyte level reduction, compared to patients with ropivacaine, clonidine and parecoxib. After 6-months follow-up, the number of patients with metastatic disease was not different.

Oral XI – Risk Factors & Outcome O-69 Are additive and logistic EuroSCOREs good predictors of early and late mortality after aortic valve replacement? Michel Durand, Evodie Boully, Yohann Dubois, Thomas Descarpentries, Vincent Bach, Dominique Blin, Pierre Albaladejo University Hospital, Grenoble, France Introduction. EuroSCORE (ES) is one of the best established risk models for cardiac surgery. However, ES seems to overestimate operative risk [1]. Thus the aim of the present study was to compare observed and predicted mortality after aortic valve replacement (AVR). Method. We prospectively followed a cohort of 394 consecutive patients who underwent isolated AVR during a 6 year period. Additive and logistic ES were calculated for each patient. Both predicted and observed mortalities were then compared. Results. Mean age was 67 years (20-93). Additive ES was 6.5 ± 2.8, logistic ES was 7.1 ± 7.7. Eight patients died and 30 daymortality was 2%. When patients were stratified according to both scores, early observed mortality did not significantly increase (table1) Logistic EuroSCORE

<10

10 to <20

≥20

P

Number of patients

324

52

18

-

Observed mortality (%)

1.9[0.4-3.4]

3.8[0 -9.0]

0

0.53

Predicted mortality (%)

4.8

12.7

34.2

<0.001

3 years mortality (%)

8

16

8

0.22

Additive EuroSCORE

0-2

3-5

Number of patients

34

66

Observed mortality (%)

0

1.5[0 -4.4]

2[0.4-3.6]

Predicted mortality (%)

2

3.7

7.7

<0.001

3 years mortality (%)

0

4

11

0.09

[95% confidence interval]

≥6 295

P 0.61

Conclusions. ES, either additive or logistic, does not correctly stratify patients undergoing AVR and over-estimates early postoperative mortality. Long term mortality was slightly influenced by the value of preoperative ES. This overestimation could lead to inappropriate indication for percutaneous AVR and misinterpretation of results [2]. References. 1. Gogbashian A, Sedrakyan A, Treasure T. EuroSCORE: a systematic review of international performance. Eur J Cardiothorac Surg 2004; 25: 695-700. Review 2. Descoutures F, Himbert D, Lepage L, et al. Contemporary surgical or percutaneous management of severe aortic stenosis in the elderly. Eur Heart J 2008; 29: 1410-1417. O-70 Prediction of a 30 day period mortality and length of hospital stay following open heart surgery: comparison between logistic EuroSCORE and Care Score in a single centre Nikolaos Lagos, Elena Arnaoutoglou, Konstantinos Krikonis, Georgios Papadopoulos University Hospital, Ioannina/Ioannina, Greece Introduction. The aim of this single-centre study was to assess the predictive value of two risk stratification systems, the Logistic EuroSCORE and the CARE (Cardiac Anaesthesia Risk Evaluation score) in a population who underwent open cardiac surgery. Method. From March 2005 to December 2006 both scores were applied to 301 adult patients who underwent elective or emergency open cardiac surgery in our hospital. Data was collected prospectively by two anaesthesiologists according to the criteria and definitions described by the two model developers. Two outcomes were examined, 30 day mortality and length of hospital stay. Random cross-checking was performed to minimize inter-observer errors. Calibration was determined by HosmerLemeshow goodness of fit statistics (HL). Discrimination was assessed by using receiver operating characteristic (ROC) curves.

S30

FREE ORAL SESSIONS

Results. Both systems predicted 30 day mortality reliably. The area under receiver operating characteristic (ROC) curves was 0.80 (95% C.I. 0.69-0.90 ) for the Logistic EuroSCORE and 0.78 (95% C.I. 0.66-0.89 ) for the CARE. The calibration analysis showed agreement between the observed and expected number of deaths, with both models. Neither of the two models showed the same discriminating ability for length of hospital stay: 0.54 (95% C.I. 0.51-0.65) for the Logistic EuroSCORE and 0.56 (95% C.I. 0.49-0.63) for the Care. Conclusions. The CARE score predicted 30 day mortality as well as the Logistic EuroSCORE in this Greek population. Both of these systems were unable to predict length of hospital stay. References. 1. Nashef SA, Roques F, Michel P, et al. European system for cardiac operative risk evaluation (EuroSCORE). Eur J Cardiothorac Surg 1999; 16(1): 9-13. 2. Dupuis JY, Wang F, Nathan H, Lam, et al. The cardiac anesthesia risk evaluation score: a clinically useful predictor of mortality and morbidity after cardiac surgery. Anesthesiology 2001; 94(2): 194-204.

O-71 Shift in severity score-mortality relationship in patients undergoing cardiac surgery Michel Durand, Evodie Boully, Yohann Dubois, Laetitia Boggetto, Vincent Bach, Olivier Chavanon, Pierre Albaldejo University Hospital, Grenoble, France Introduction. Over 10 years, a slight change in severity of patients undergoing cardiac surgery has been observed. However, the relationship between severity scores and mortality is rarely reassessed. Thus the aim of this study was to evaluate these changes using severity scores. Method. Data of 5432 patients undergoing cardiac surgery in this hospital were prospectively collected between January 1998 and June 2008. These 10.5 years were divided in 3 periods of 3.5 years. Parsonnet score [1], Tu (Ontario) score [2] and EuroSCORE [3] were calculated as described in the original studies. The end point was 30 days mortality. Results. Mean values of the different scores were 5.2 for the EuroSCORE, 11.7 for the Parsonnet score, 3.3 for the Tu score. Length of stay in ICU, but not length of mechanical ventilation increased significantly during the study period.

EuroSCORE EuroSCORE>5 (%) Parsonnet TU score Tu score > 3 (%) Mortality (%)

Period I

Period II

Period III

P

4.4 ± 3.0 31 9.8 ± 8.6 2.7 ± 2.2 31 3.9

5.3 ± 3.4 44 11.7 ± 8.8 3.4 ± 2.5 43 4.7

5.7 ± 3.4 50 12.9 ± 9.6 3.8 ± 2.6 50 4.7

<0.0001 <0.0001 <0.0001 <0.0001 <0.0001 0.45

Conclusion. Despite an increase in estimated operative risk, postoperative mortality did not significantly increase during the study period. This may be due to improved perioperative care. However, these changes were associated with an increase in resource utilization. References. 1. Parsonnet V, Dean D, Berstein AD, et al. A method of uniform stratification of risk for evaluating the results of surgery in acquired adult heart disease. Circulation 1989; 79: I3-12. 2. Tu JV, Jagial SB, Naylor CD. Multicenter validation of a risk index for mortality, intensive unit stay, and overall hos-

3.

pitality length of stay after cardiac surgery. Steering Committee of the Provincial Adult Cardiac Network of Ontario. Circulation 1995; 91: 677-684. Nashef SA, Roques F, Michel P, et al. European system for cardiac operative risk evaluation (EuroSCORE). Eur J Cardiothorac Surg 1999; 16: 9-13.

O-72 Accuracy, calibration and clinical information of the EuroSCORE: no need for too many variables Marco Ranucci, Serenella Castelvecchio, Lorenzo Menicanti IRCCS Policlinico S.Donato, San Donato Milanese (Milan), Italy Introduction. The European system for cardiac operative risk evaluation (EuroSCORE) is currently used in many institutions and is considered a reference tool in many countries. We hypothesized that too many variables were included in the EuroSCORE using limited patient series. We tested different models using a limited number of variables. Method. 11,150 adult patients receiving cardiac operations at our institution (2001-2007) were retrospectively analysed. The 17 risk factors composing the EuroSCORE were separately analysed and ranked for accuracy of prediction of hospital mortality. Seventeen models were created by progressively including one factor at a time. The models were compared for accuracy with a Receiver Operating Characteristics analysis and Area Under the Curve (AUC) evaluation. Calibration was tested with Hosmer-Lemeshow statistics and information quality with the Akaike’s Information Criterion (AIC) statistics. Results. The best accuracy (AUC 0.76) was obtained using a model including only age, left ventricular ejection fraction, serum creatinine, emergency operation, and non-isolated coronary operation. Addition of other factors did not improve the accuracy of the model, and the EuroSCORE AUC (0.75) was not significantly different. Calibration was better in the 5-factor model than in the EuroSCORE. AIC statistics demonstrated more reliable information for the 5-factor model than for the EuroSCORE. Conclusions. Including many factors in multivariable logistic models increases the risk for over-fitting, multi-co-linearity, and human error. A 5-factor model offers the same level of accuracy but demonstrated better calibration and information reliability. Models with a limited number of factors may work better than complex models when applied to a limited number of patients. References. 1. Roques F, Nashef SA, Michel P, et al: Risk factors and outcome in European cardiac surgery: analysis of the EuroSCORE multinational database of 19030 patients. Eur J Cardiothorac Surg 1999; 15: 816-822. 2. Concato J, Feinstein AR, Holford TR. The risk of determining risk with multivariable models. Ann Intern Med 1993; 118: 201-210. Review O-73 The impact of EuroSCORE and postoperative heart failure on long-term outcome after surgery for aortic stenosis Henrik Hultkvist, Farkas Vanky, Rolf Svedjeholm Dept Cardiothoracic Surgery, Linkoping University Hospital, Linkoping, Sweden Introduction. EuroSCORE was developed for predicting operative mortality after cardiac surgery. Recently it has also been reported to predict long-term mortality. We have reported that postoperative heart failure (PHF) has a profound impact on fiveyear survival. Here we present results on late mortality after

FREE ORAL SESSIONS

isolated aortic valve replacement related to both additive EuroSCORE and PHF. Method. All patients undergoing isolated aortic valve replacement (AVR) due to aortic stenosis from 1995-2000 were studied (n=398). The cohort was divided into a high-risk group (>7) and a low risk group (≤7) according to additive EuroSCORE and further analysed in relation to PHF. Average follow-up was 8.1 years (range 5.2 – 11.2). Results. The average age was 70±7 years and 48% were females. Thirty-day mortality was 2% for the whole cohort. Fortyfive patients (11%) required treatment for PHF. Patients with low risk EuroSCORE and without PHF (n=308) had a 5-year mortality of 11% while patients with high risk EuroSCORE without PHF (n=45) had a 5-year mortality of 36%. Patients with PHF and low risk EuroSCORE (n=25) had a 5-year mortality of 40% and patients with PHF and high risk EuroSCORE (n=20) had a 5year mortality of 45%. Conclusions. The majority of patients undergoing isolated AVR had a good long-term outcome. Both PHF and high EuroSCORE were associated with a profound impact on long-term survival. The role of PHF per se for long-term prognosis was illustrated by the fact that the negative impact on long-term survival was almost as profound in patients in the low risk group as in the high risk group. Given that preoperative risk factors are difficult to modify at the time of surgery better treatment of and avoidance of PHF appears essential to improve long-term outcome. Reference. 1. Vánky FB, Håkanson E, Svedjeholm R. Long-term consequence of postoperative heart failure after surgery for aortic stenosis compared with coronary surgery. Ann Thorac Surg 2007; 83: 2036-2043. O-74 Risk factors for selected complications after cardiac surgery

Introduction. Eight variables (shock, chronic renal failure, left ventricle ejection fraction (LVEF), intraoperative hypotension, NYHA class, previous cardiac surgery, peripheral hypothermia, age) have been assessed as potential predictors of selected early postoperative complications [1]. The aim of this study was to weight the predictive capability of the variables with respect to complications attributable to inflammatory response to cardiac surgery - respiratory failure (RF), acute renal failure (ARF), and postoperative delirium (PD). Method. A prospective, observational, case control study of 2066 patients was carried out. Backward logistic regression was used to identify the most predictive model for each complication. Results. In 2066 patients, 678 (32.8%) women, 1388 (67.2%) men, mean age 64 (SD ±11) years, inflammation-attributable complications occurred in 225 (10.9%; 95% CI: 9.6-12.3). They were RF in 115 (5.6%; 95% CI: 4.6-6.7), ARF in 80 (3.9%; 95% CI: 3.1-4.8), and PD in 112 (5.4%; 95% CI: 4.5-6.5). Odds ratios are presented in the table.

S31

Table. Predictor

RF

ARF

PD

Shock

4.90

6.19

4.29

Chronic renal failure

2.33

5.65

ns

LVEF [per 5%]

0.98

ns

0.98

Intraoperative hypotension

2.34

2.43

ns

NYHA class

1.44

1.58

1.35

Previous cardiac surgery 0

Peripheral hypothermia – delta Temp >5 C Age [per year] Likelihood ratio of the model

ns

ns

ns

2.90

2.54

ns

ns

ns

1.07

161.15

172.96

90.06

Discussion. Preoperative shock and NYHA class were universal predictors for all three complications. Shock before operation increased the most risk of complications attributable to inflammation. Age was predictive only for PD. Reference.

O-75 Factor analysis of World Health Organization’s Quality of Life-BREF health survey questionnaire in patients with coronary artery disease Mahdi Najafi, Mehrdad Sheikhvatan, Mahmood Sheikhfathollahi Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran Introduction. WHOQOL-BREF is one of the most applicable general questionnaires for assessment of quality of life (QOL) in both healthy populations and various disease subgroups. The aim of the present study was to examine construct validity of this questionnaire using factor analysis in patients with coronary artery disease. Method. Two hundred and seventy-five patients aged 35 to 80 years old with the diagnosis of CAD were consecutively entered into the study. To assess the QOL in study subjects, the WHOQOL-BREF questionnaire was completed with interviewing. To estimate the Reliability of QOL questionnaire, Cronbach’s coefficient was measured. We firstly used confirmatory factor analysis to test the hypothesized 2-factor and 3-factor models, separately. Exploratory factor analysis was then performed with iterated principal / component method and varimax rotation for the 4 subscales of the WHOQOL-BREF. Results. Moderate correlations were observed between environmental domain and both psychological and social domains (r=0.437 and r=0.515, respectively). However, other interdomain correlations were weak (r<0.4). In confirmatory factor analysis, the fit indices indicated poor model fits of the two hypothesized factor models. On the basis of exploratory factor analysis, four domains of the questionnaire were included in one factor that accounted for 53.7% of the variance in all domains. Discussion. The WHOQOL-BREF health survey questionnaire may be structured in one factor that measures overall QOL in patients with coronary artery disease and describes their wellbeing and satisfaction.

S32

FREE ORAL SESSIONS

O-76

CUSUM SAPSII

Pre- and postoperative risk-adjusted cumulative survival curves as a surrogate for team quality control in cardiac surgery patients

29

Daniel Schmidlin, Tomislav Gaspert, Sabine Serena, Patricia Rhomberg, Pascal Berdat, Paul R. Vogt

19

CSUSUM EuroSCORE

Difference SAPS II - EuroSCORE

24

14

Hirslanden Klinik Im Park, Zurich, CH-8006, Switzerland Introduction. Variable life adjusted displays (VLAD) [1] or cumulative survival curves (CUSUM) have been used for process quality control. A scoring-system based on expected in-hospital (or 30-day) mortality is compared with the correlating observed mortality. Individual results are displayed as a sum of the expected/observed mortality ratio over time. Thus, a survivor gets her/his individual risk as beneficial (“+”) while a non surviving patient’s risk is entered as “minus” (1-exp mortality). We compared VLADs based on pre- and postoperative risk evaluation systems in individuals having cardiac surgery in order to compare intra- and postoperative performance of the corresponding teams over time. Method. In-hospital survival of cardiac surgery patients in a non-teaching hospital were analysed over a longer period of time with CUSUM curves. One curve based on EuroSCORE (preop risk) and the other on SAPS II (postop physiologic risk and a consequence of intraop events).

9 4 -1

1

17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 289 305 321 337 353 369 385 401 417 433 449 465 481 497 513

-6

Results. Between 2006 and 2008 mortality in the hospital of 514 patients was analysed. A total of 15 patients died over this period in the hospital. Overall “gain” of human lives according to EuroSCORE was 27.1; based on SAPS II it was 32.3. The two curves and their difference over time were used to control process quality over time (Fig). The results of our single centre experience show a quite constant performance of the intra- and the postoperative teams over time since the difference of observed/expected mortality according to EuroSCORE and SAPS II did not exceed 2 standard deviations. Reference 1. Lovegrove J, Valencia O, Treasure T, et al. Monitoring the results of cardiac surgery by variable life-adjusted display. Lancet 1997; 350: 1128-1130.

Oral XII – Myocardial Protection O-77 Propofol inhibits L-type Ca diomyocytes

2+

currents in human atrial car-

Jens Fassl, Kane M High, Edward R Stephenson, Keith S Elmslie Milton S Hershey Medical Center, Hershey, Pennsylvania, United States 2+

Introduction. Volatile anaesthetics inhibit human L-type Ca channels [1], but the effect of the i.v. anaesthetic agent propofol has yet to be investigated. Method. Human atrial myocytes were isolated from right atrial appendages obtained as surgical specimens from patients (n=4) undergoing open heart surgery. All patients were in sinus rhythm and had no evidence of right atrial dysfunction. L-type 2+ Ca currents were recorded using the whole cell patch clamp +2 technique in an external solution containing 5 mM Ca . Measurements were made from 200 ms steps to the voltage that elicited peak current (+10mV). The myocytes were superfused with external solution containing 100 µM propofol and the experiments were carried out at room temperature (21-23°C). Results. The application of 100 µM propofol resulted in a rapid and reversible inhibition of L-current (33.1 ± 19.5%, mean ± SD, n=4), suggesting that either maximal inhibition was only partial or that 100 µM was less than the IC50 for inhibition. These two hypotheses were examined in preliminary experiments using either 10 or 300 µM propofol. The inhibition in 300 µM propofol was 39.5% (n=1), while that in 10 µM was 25.9% (n=1). Thus, propofol appears to induce a partial inhibition of atrial L-current with an IC50 >10 µM. These conclusions were further supported by recordings from HEK293 cells transiently expressing the Lchannel + β2a and α2δ (n=3), where propofol inhibited L-current by 23.3 ±14.3% (10 µM) and 38.7 ± 0.6% (30 µM). Conclusion. We demonstrate that propofol inhibits human atrial +2 L-type Ca current at clinically relevant concentrations, which

may help explain the negative side effects like hypotension and arrhythmias associated with propofol-induced anaesthesia. Reference. 1. Hüneke R, Jüngling E, Skasa M, et al. Effects of the anesthetic gases xenon, halothane, and isoflurane on calcium and potassium currents in human atrial cardiomyocytes. Anesthesiology 2001; 95: 999-1006. O-78 Effects of volatile anaesthetics on left ventricular diastolic function in healthy young subjects Daniel Bolliger, Jorge Kasper, Regina M. Schumann, Esther Seeberger, Karl Skarvan, Manfred D. Seeberger, Miodrag Filipovic University of Basel Hospital, Basel, Switzerland Introduction. Global left ventricular (LV) performance is critically determined by diastolic function. We aimed to evaluate the effects of desflurane, isoflurane, or sevoflurane on LV diastolic function during mono-anaesthesia and spontaneous breathing (SB) or intermittent positive pressure ventilation (IPPV) in healthy young patients. Method. After ethical approval and informed consent, we studied 60 otherwise healthy patients (31 ± 9 years; 20 women) scheduled for minor surgical procedures under general anaesthesia. After randomization, anaesthesia was induced with remifentanil delivered by a target controlled infusion system and either desflurane (Des), isoflurane (Iso), or sevoflurane (Sevo). Remifentanil was stopped after insertion of a laryngeal mask, and the volatile anaesthetic adjusted to 1 MAC. Transthoracic echocardiographic (TTE) studies were performed in the awake state (baseline, BL) and during general anaesthesia and SB (Step I) or IPPV (Step II) with 1 MAC of the volatile anaesthetic and no remifentanil (endorgan concentration <0.1 ng/mL). Analyses focussed on the rela-

FREE ORAL SESSIONS

S33

tion of early to late trans-mitral peak flow velocities (E/A), and early diastolic mitral annulus velocities (E’) obtained by pulsedwave Doppler tissue imaging. Results. Presented as mean (SD): BL Des

Iso

Step I Sevo

Des

Iso

Step II Sevo

Des

Iso

Sevo

1.8

1.7

1.8

2.5

2.1

2.0

2.3

1.7

1.8

(0.6)

(0.4)

(0.5)

(1.1)

(0.6)

(0.6)

(0.9)

(0.5)

(0.7)

14.5

13.7

14.0

17.1

14.6

13.2

14.8

12.5

11.4

(1.7)

(2.5)

(2.6)

(2.3)

(2.1)

(2.3)

(2.0)

(2.0)

(2.0)

E/A

P 0.044

E’

<0.001

Discussion. With the exception of one patient during 1 MAC of sevoflurane and IPPV, we found no signs of diastolic dysfunction induced by volatile anaesthetics. Desflurane tended even to improve early diastolic function. This is in contrast to former animal studies, but in agreement with former studies in healthy humans [1]. Reference. 1. Filipovic M, Wang J, Michaux I, et al. Effects of halothane, sevoflurane and propofol on left ventricular diastolic function in humans during spontaneous and mechanical ventilation. Br J Anaesth 2005; 94: 186-192. O-79 A meta-regression on 34,310 patients undergoing CABG: the role of volatile anaesthetics Massimiliano Nuzzi, Elena Bignami, Valentina Testa, Anna Mizzi, Stefano Turi, Elisa Dedola, Giovanni Landoni, Alberto Zangrillo Ospedale San Raffaele - Università Vita-Salute San Raffaele, Milano, Italy Introduction. A recent meta-analysis [1] showed that desflurane and sevoflurane reduce postoperative mortality and myocardial infarction following cardiac surgery [1]. Whether halogenated anaesthetics improve the outcome of cardiac surgical patients is still a matter of debate. Method. A longitudinal study of 34,310 CABG interventions was performed between 2002 and 2004 in 64 Italian cardiosurgical centres [2]. They estimated a risk-adjusted mortality ratio (RAMR) for each centre. We conducted a survey among the same 64 centres to investigate whether the use of halogenated anaesthetics showed a correlation with the RAMR. Results. Mortality was reduced in centres using volatile anaesthetics when compared to centres using total intravenous anaesthesia. Discussion. Our regression analysis shows that risk-adjusted mortality is significantly related to the use of halogenated agents during surgery and to the duration of volatile anaesthetic administration. Our findings are in agreement with the results of a recently published meta-analysis [1], which found a favourable effect of halogenated anaesthetics on mortality in cardiac surgical patients. References. 1. Landoni G, Biondi-Zoccai GG, Zangrillo A, et al. Desflurane and sevoflurane in cardiac surgery: a meta-analysis of randomized clinical trials. J Cardiothorac Vasc Anesth 2007; 21: 502-511. 2. Seccareccia F, Perucci CA, D’Errigo P, et al. The Italian CABG Outcome Study: short-term outcomes in patients with coronary artery bypass graft surgery. Eur J Cardiothorac Surg 2006; 29: 56-62, discussion 62-64.

S34

FREE ORAL SESSIONS

O-80

O-81

High thoracic epidural analgesia improves cardiac function in patients with ischaemic heart disease undergoing cardiac surgery

Levosimendan infusion for preoperative management of hypoplastic left heart syndrome

Carl-Johan Jakobsen, Hans Kirkegaard, Christian Lindskov, Inge Krogh Severinsen, Erik Sloth

Luca Di Chiara, Zaccaria Ricci, Cristiana Garisto, Stefano Morelli, Chiara Giorni, Sergio Picardo Bambino Gesù Hospital, Rome, Italy

Aarhus University Hospital, Skejby, Aarhus, Denmark Introduction. In patients with ischaemic heart disease, high thoracic epidural analgesia (HTEA) has been proposed to improve myocardial function. The purpose of this study was to evaluate the effect of HTEA on haemodynamic function during cardiac surgery. Method. A prospective randomized study was made of 60 patients undergoing CABG, aortic valve replacement or combination surgery in a University Hospital. All patients were monitored with continuous cardiac index (CI) and SVO2 with simultaneous arterial and venous pressure measurements, registered every 5 minutes during surgery. Results. Cardiac index and stroke volume index (SVI) were statistically significantly higher in patients with HTEA both before and after cardiopulmonary bypass (CPB), while mean arterial pressure (MAP), heart rate (HR) and rate pressure product (RPP) were all lower in both periods. During CPB, MAP was lower, while CVP and peripheral saturation (SAT) were higher in HTEA patients. Subgroup analysis showed that the effect of HTEA on CI and SVI was greater in patients only undergoing CABG. Table 1. Pre-CPB

Mean values

Post-CPB

Epidural

No

P-value

Epidural

No

P-value

MAP

73.2

77.6

<0.001

70.0

73.7

0.001

HR

59.7

62.4

<0.001

81.0

82.3

0.277

RPP

4,453

4,864

0.001

5,702

6,061

0.002

CCI

2.2

2.0

0.001

2.7

2.5

0.031

SVI

39.6

33.5

<0.001

34.4

31.5

0.009

Table 2. During CPB Mean values

Epidural

No

P value

MAP

56.4

64.8

<0.001

SAT

97.5

96.5

<0.001

CVP

11.7

10.5

0.023

Conclusion. High thoracic epidural anaesthesia seems to improve cardiac function during cardiac surgery especially in patients with ischaemic heart disease. References. 1. Royse C, Royse A, Soeding P, et al. Prospective randomized trial of high thoracic epidural analgesia for coronary artery bypass surgery. Ann Thorac Surg 2003; 75: 93-100. 2. Berendes E, Schmidt C, Van Aken H, et al. Reversible cardiac sympathectomy by high thoracic epidural anesthesia improves regional left ventricular function in patients undergoing coronary artery bypass grafting: a randomized trial. Arch Surg 2003; 138: 1283-1290.

Introduction. Hypoplastic left heart syndrome (HLHS) is characterized by a perioperative impaired myocardial function and critical inefficiency of the parallel circulations. The preoperative management of these patients requires inotropic therapy to treat the haemodynamic instability. The aim of our study was to evaluate the safety and the efficacy of a preoperative infusion of levosimendan on neonates affected by HLHS. Method. Ten consecutive HLHS neonates were enrolled. All -1 -1 patients started levosimendan infusion at 0.1 µg kg min 24 hours before surgery. Patients requiring intubation were ventilated with an FiO2 of 25%. Results. All enrolled patients were scheduled for a Norwood procedure with Blalock Taussig shunt within the first 7 days of life. Eight of 10 children presented with pulmonary overcirculation, poor systemic perfusion and metabolic acidosis and required intubation. Before starting the levosimendan infusion patients presented a median (interquartile range) Qp/Qs of 4 (1.5-5). In the first 24 treatment hours, Qp/Qs decreased to 3 (2.5-4.2) (P<0.05). Heart rate and mean arterial pressure did not show significant modifications during the preoperative phase. pH remained above 7.45, HCO3 improved from 26.0 to 28.2 (P<0.05) and base excess increased from 2.7 to 3.4 (P<0.05). Median Brain Natriuretic Peptide levels significantly decreased from 1079 to 884 pg/mL (P<0.05) and lactate levels improved from 2.7 mmol/L to 1.6 mmol/L. SvO2% increased from 60 to 68% (P<0.05) and ∆avO2 decreased from 33 to 26 after 24 hours (P<0.05). Cerebral Near-Infrared Spectroscopy (NIRS) values increased significantly soon after levosimendan infusion from 64 to 72% (P<0.05), whereas renal NIRS modifications did not reach statistical significance. After surgery, 9 of 10 patients were discharged alive from ICU. Discussion. Our trial is the first prospective study on preoperative levosimendan administration in a cohort of neonates with HLHS [1]. We showed significant improvement of haemodynamic and metabolic parameters after 24 hours of levosimendan therapy and improvement of systemic perfusion. No side effects were shown and levosimendan infusion was never stopped after treatment start. Preoperative levosimendan infusion might be considered as a new strategy to improve the outcome of these neonates. Reference. 1. Stocker CF, Shekerdemain LS, Nørgaard MA, et al. Mechanism of reduced cardiac output and the effects of milrinone and levosimendan in a model of infant CPB. Crit Care Med 2007; 35: 252-259.

FREE ORAL SESSIONS

S35

O-82 Atrial synchronous right ventricular outflow tract pacing is associated with increased plasma BNP in troponin-T negative CABG patients with reduced left ventricular function 1

3

3

Matthias Heringlake , Frank Eberhardt , Maximillian Massalme , 2 2 Martin Misfeld , Thorsten Hanke 1

2

Dept. of Anesthesiology, Dept. of Thoracic Vascular and Car3 diac Surgery, Dept. of Cardiology, University of Lübeck, Lübeck, Germany Introduction. Atrial synchronous biventricular pacing (DDD-BV) reduces systolic asynchrony and improves steady state and preload independent parameters of cardiac function in patients with reduced left ventricular ejection fraction, in comparison with conventional sequential right-ventricular outflow pacing (DDDRV) in the immediate period after on-pump CABG. A RCT investigating the long term effects of AAI, DDD-RV, and DDD-BV pacing (the BIVAC-trial) failed to reveal any differences between the different pacing modes on clinically relevant outcomes [1]. However, this trial was performed in a relatively heterogeneous population of CABG patients partially presenting with non-ST elevation myocardial infarction and/or moderate to severe mitral regurgitation (MR), entities that may have influenced clinical outcomes as well as hormonal activation. The present post hoc analysis of the BIVAC trial was aimed to determine the effects of different pacing modes in a subset of the BIVAC patients that had either none or only minor MR and were troponin-T (TT) negative at inclusion on the course of plasma BNP levels. Method. Fifty six patients (AAI: 18 DDD-RV: 20; DDD-BV:18) from the BIVAC database were identified who were preoperatively TT negative and had preoperative MR grade 0 or 1. The course of plasma B-type natriuretic peptide (BNP) was determined before and 24, 48, and 72h after surgery. Results. The groups did not differ regarding demographics and surgical data (data not shown). The DDD-RV group showed a pronounced and significant increase of plasma BNP- levels 24 to 72h after surgery in comparison with the AAI and the DDDBV-group. Conclusions. These data suggest that atrial synchronous right ventricular outflow pacing is inferior to AAI or DDD-BV pacing with regard to cardiac hormonal activation in patients with reduced LVEF undergoing on-pump CABG surgery. Reference. 1. Hanke T, Misfeld M, Heringlake M, et al. Biventricular pacing in patients with severely reduced LV function after CABG - The BIVAC trial. Circulation 2007; 116: II-681.

O-83 Relationship between SvO2 on arrival in ICU and postoperative morbidity and mortality after CABG 1

1

1

Rolf Svedjeholm , Jonas Holm , Farkas Vanky , Erik Håkanson 1

2

2

Dept Cardiothoracic Surgery, Dept Cardiothoracic Anaesthesia, Linköping University Hospital, Linköping, Sweden

Introduction. Mixed venous oxygen saturation (SvO2) and cardiac output are used for haemodynamic monitoring after cardiac surgery. However, neither level of cardiac output nor SvO 2 has been adequately studied with regard to outcome variables after cardiac surgery. In a highly selected cohort of patients undergoing CABG and treated according to a metabolic strategy SvO 2 <55% on arrival in ICU was associated with increased morbidity and mortality. The aim of this study was to investigate the relationship between SvO2 and postoperative outcome in an unselected cohort of patients undergoing isolated CABG at our institution.

Method. SvO2 was routinely measured on arrival in ICU and registered in a database. SvO2 was categorized in 5% intervals and related to outcome variables for 2757 consecutive patients undergoing isolated CABG procedures. Results. A marked increase in postoperative mortality was seen in patients with SvO2 <60% on arrival to ICU. Outcome after 448 procedures with SvO2 <60% compared with 2309 procedures with SvO2 ≥60% showed 30-day mortality 5.6% vs. 1.0% (P<0.0001), perioperative myocardial infarction 13.7% vs. 5.1% (P<0.0001), stroke 3.6% vs. 1.9% (P=0.02), reoperation for bleeding 5.6% vs. 2.5% (P=0.0005) and ventilator treatment >24 hours 14.3% vs 4.9% (P<0.0001). Conclusions. In an unselected cohort undergoing isolated CABG at our institution, a marked increase in postoperative mortality and morbidity was observed in patients with SvO2 <60% on arrival in the ICU. Reference. 1. Svedjeholm R, Håkanson E, Szabó Z. Routine SvO2 measurement after CABG surgery with a surgically introduced pulmonary artery catheter. Eur J Cardiothoracic Surg 1999; 16: 450-457. O-84 Long-term results of drug-eluting stents in diabetic patients according to diabetic treatment Vassilis Voudris, Panagiotis Karyofillis, Sophia Thomopoulou, Athanasios Manginas, Constantinos Spargias, Gregory Pavlides, Dennis V Cokkinos Onassis Cardiac Surgery Center, Athens, Greece Introduction. In this prospective single centre study, we assessed the short- and long-term results of drug-eluting stents (DES) in non-insulin dependent (NID) compared to insulin dependent (ID) diabetic (D) patients (pts). Method. A total of 610 consecutive pts (mean age 65±9 years) who had been treated with DES (sirolimus 80%, paclitaxel 10%, zotarolimus 2%, combination 8%) were classified in 2 groups according to D treatment pre- PCI: 1) NID (477 pts,); 2) ID (133 pts). The in-hospital results and clinical outcome during followup (FU) (median 29 months) was obtained in 597/610 pts (98%). Major adverse cardiac events (MACE) during follow-up were considered to be death, myocardial infarction (MI), bypass surgery (CABG), target (TLR) and non-target (non-TLR) lesion revascularization. Dual antiplatelet treatment for 12 months was received by 93%, for more than 12 months by 72%. 93% of pts. received statin treatment. Results. The ID group had more women (29% vs. 18%, P=0.005), a higher incidence of multivessel disease (84% vs. 65%, P<0.001) and ejection fraction <40% (16% vs. 9%, P=0.04) compared to the NID group. The clinical success rate (angiographic success without death, Q-wave MI or emergency CABG) was similar (99.2% in ID vs. 99.6% in NID pts). However, ID pts had a higher incidence of non-Q wave MI (9.8% vs. 4.8%, P=0.04) and more bleeding complications (1.5% vs. 0%, P=0.05). Complete revascularization was achieved more frequently in NID pts (48%, vs. 29%, P<0.001). At clinical follow-up there was no difference in death or non-fatal MI (8.5% vs. 6.2%), definite or probable stent thrombosis (1.6% vs. 0.6%), or overall stent thrombosis (5.4% vs. 3%) between ID and NID pts. However there was a higher rate of CABG (4.7% vs. 1.1%, P=0.02), and TLR (8.5% vs. 3.4%, P=0.03) in ID pts, while nonTLR was similar (14% vs. 12%). The primary end point at followup (death, MI, TLR or CABG) was higher in ID pts (adjusted HR, 0.52; 95% CI, 0.31-0.85, P=0.01). Conclusion. The implantation of DES in pts with DM is associated with excellent in-hospital and long-term results. Even so, the long-term effectiveness in ID pts is lower due to an increased risk for new revascularization.