O-74 A word of caution for using hypertonic hydroxyethyl starch solution in valvular heart surgery

FREE ORAL SESSIONS

S31

Oral Session XII – Drug & Fluids and Organ Function & Protection O-72

University of Lübeck, Lübeck, Germany

Supplement of epidural analgesia seems to improve outcome in cardiac surgery Mads Hansen1, Henrik Schmitdt1, Henrik Karsten Berg1, Carl-Johan Jakobsen2 1 Odense University Hospital, Odense, Denmark, 2Aarhus University Hospital, Skejby, Aarhus, Denmark

Introduction. In a meta-analysis of 2,366 patients (33 trials) it was concluded that epidural analgesia in combination with general anaesthesia reduced the incidence of acute renal failure, the time on mechanical ventilation and the composite endpoint of mortality and MI in patients undergoing cardiac surgery [1]. However, definitions of endpoints may vary and no major single centre study has been published. Method. All consecutive patients in 2008-10 were obtained from our database (n⫽1,747). Patients with rare procedures, aortic surgery and TAVI were a priori excluded, leaving 1,440 procedures. Epidural/No-epidural were matched for age group, sex, residual EuroSCORE and operation type giving a cohort for analysis of 1,078 procedures with exact match. All preoperative and outcome data are registered prospectively in our database. Mortality is checked daily against the Danish civil registration system. Result. As shown in the table there was no difference between the groups in age, sex and EuroSCORE between the matched groups. All outcome parameters showed a lower tendency in the epidural group. However only the combined outcome index was significant (P⫽0.008). The median ventilation time was lower after epidural (P⬍0.001), while we found no difference in median ICU time or in-hospital time. The lower ventilation time was a result of a policy of extubation in the OR if possible.

Epidural

No

Female

Mean age (years)

No Yes

539 539

137 137

66.9 67.2

30 daysmortality No Yes

Postop. dialysis

20 (3.7%) 23 (4.3%) 14 (2.6%) 17 (3.2%)

EuroSCORE

Vent. Time (hours)

ICU time (hours)

5.4 1.8

22.0 21.8

4.74 4.74

Postop. MI

Postop. Stroke

Comb. outcome

Hosp. Time

30 (5.6%) 18 (3.2%)

10 (1.9%) 4 (0.7%)

62 (11.5%) 43 (8.0%)

6.0 6.0

Conclusion. This single centre study of 3 years’ procedures suggest a lower incidence of 30-day mortality and postoperative MI, stroke and need for dialysis after cardiac surgery combined with epidural analgesia. REFERENCE 1. Bignami E, Landoni G, Biondi-Zoccai GG, et al. Epidural analgesia improves outcome in cardiac surgery: a meta-analysis of randomized controlled trials. J Cardiothorac Vasc Anesth 2010; 24: 586-97. O-73 Perioperative sodium bicarbonate infusion fails to improve renal function in clinical practice: a prospective cohort study Julika Schön, Maria Schubert, Janina Guder, Maria Kleinebrahm, Yvonne Nowak, Hauke Paarmann, Hermann Heinze, Matthias Heringlake

Introduction. Recent evidence from a pilot trial in 100 patients suggests that a continuous, 24 hour infusion of sodium bicarbonate, started preoperatively on the day of surgery, reduces the incidence of cardiac-surgery-associated acute kidney injury (CSA-AKI) [1]. The present cohort study aims to determine the kidney protective effects of this intervention in a larger and heterogeneous population during routine practice. Method. From April to December 2009 patients scheduled for cardiac surgery were studied perioperatively until the third postoperative day. Plasma creatinine and growth-determination factor 15 (GDF-15), a peptide of the transforming growth factor family related to glomerular filtration rate, were determined preoperatively, at the end of surgery, and on the morning of the first, second, and third postoperative day. Analysis was performed in a cohort of 408 untreated patients (from April to July) in comparison with a cohort of 363 patients routinely treated with sodium bicarbonate (SBIC) starting in 8/2010. Mann-Whitney-Utest or chi-squared-test were used as appropriate. Results. Preoperative demographics, surgical procedures, duration of cardiopulmonary bypass, baseline plasma creatinine and estimated glomerular filtration rate as well as baseline GDF-15 were comparable in both groups. 10.1% of patients in the control period and 12.6% of patients treated with SBIC needed renal replacement therapy postoperatively (P⫽n.s.). No differences in the perioperative time course of plasma creatinine and plasma-GDF-15 were observed. Comparably, grading of postoperative renal dysfunction according to the AKI-criteria failed to show significant differences between both cohorts. Conclusions. The results of the present study do not support the concept that a routine perioperative treatment with sodium bicarbonate has renal protective effects in patients undergoing cardiac surgery. REFERENCE 1. Haase M, Haase-Fielitz A, Bellomo R, et al. Sodium bicarbonate to prevent increases in serum creatinine after cardiac surgery: A pilot double-blind, randomized controlled trial. Crit Care Med 2009; 37: 39-47. O-74 A word of caution for using hypertonic hydroxyethyl starch solution in valvular heart surgery Vladimir Shmyrev, Vladimir Lomivorotov, Dmitriy Ponomarev Academician E.N. Meshalkin Research Institute of Circulation Pathology, Novosibirsk, Russia Introduction. Several studies reported beneficial effects from using hyperosmotic-hyperoncotic solutions in on-pump cardiac surgery [1]. In this randomized study we aimed to examine effects of using hypertonic hydroxyethyl starch solution (HyperHaes®, Fresenius) in patients operated under cardiopulmonary bypass (CPB). Method. Fifteen patients undergoing valve replacement either received an infusion of 7.2% NaCl in 6% hydroxyethyl-starch (1 ml kg-1 h-1, total dose 4 ml/kg) started after induction or an equivalent dose of 0.9% NaCl, according to blind randomization protocol. Groups were well matched. Anaesthetic technique and

S32

FREE ORAL SESSIONS

postoperative management were standardized. Endpoints were changes of intra-thoracic blood index (⌬ITBI), extra-lung water index (⌬ELWI), pulmonary vascular permeability index (⌬PVPI), ventilation time, serum sodium concentration. Mann-Whitney U-test was used to evaluate the differences between groups. P⬍0.05 was considered significant. Results. Incidence of complications was 2 (25%) and 3 (37.5%) for neurologic event and acute kidney injury (AKI) respectively in the experimental group. There was no neurologic event and 1 case (14.3%) of AKI in the control group. Haemodynamics, ⌬ITBI, ⌬ELWI, ⌬PVPI, fluid balance, ventilation time were not different between groups. The HyperHAES group showed elevated levels of serum sodium concentration compared to control at all the time points from 4 h to 48 h postoperatively (P⬍0.05). Discussion. The study was prematurely terminated due to a high incidence of complications in the group being studied. Our current investigation reveals no benefits from using hyperosmotic-hyperoncotic solution in patients undergoing valve replacement. A relatively high rate of complications seen in the HyperHAES group should raise caution in using this solution and promote further investigations of its effects. REFERENCE 1. Azoubel G, Nascimento B, Ferri M, et al. Operating room use of hypertonic solutions: a clinical review. Clinics (Sao Paulo) 2008; 63: 833-40. Review. O-75 Effects of prolonged nutritional support on liver enzymes in patients undergoing open heart surgery Buket Ozyaprak, Ayse Baysal, Ismail Ozkaynak, Tuncer Kocak Kartal Kosuyolu Training and Research Hospital, Kartal, Istanbul, Turkey Introduction. The effects of prolonged nutritional support on liver function tests (LFTs) in patients with congestive heart failure who underwent open heart surgery (coronary artery bypass graft (CABG) or valve repair surgery) that required prolonged mechanical ventilation and nutritional support were investigated. Method. Sixty patients with signs of congestive heart failure and an ejection fraction below 40%, undergoing open heart surgery, were investigated. 31 patients (51%) had CABG and 29 (49%) had valve repair surgery. All patients received enteral and total parenteral nutrion for a period of 15 days. The collected data preoperatively and on postoperative day 1, 7 and 14 included albumin (Alb), alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), total bilirubin (TBIL) and gamma glutamyl transpeptidase (GGT). Complications were recorded. Parameters ALP*(mg/dL) AST*(mg/dL) ALT*(mg/dL) LDH*(mg/dL) TotalBilirubin (mg/dL) GGT*(mg/dL)

Day 1

Day 7

Day 14

Day 1-14 P*

107.9 ⫾ 37.5 65.7 ⫾ 38.3 37.8 ⫾ 24.9 765.0 ⫾ 227.7 1.0 ⫾ 0.5

98.9 ⫾ 37.1 55.6 ⫾ 31.3 38.6 ⫾ 28.0 782.6 ⫾ 298.8 1.1 ⫾ 0.5

96.3 ⫾ 45.3 55.2 ⫾ 37.6 35.5 ⫾ 3.8 700.3 ⫾ 268.7 1.1 ⫾ 0.5

0.03* 0.02* 0.34 0.02* 0.20

51.5 ⫾ 33.5

53.4 ⫾ 35.7

61.3 ⫾ 40.1

0.03*

*P: P⬍0.05 statistically significant; CABG; coronary artery bypass graft; alanine transaminase (ALT); aspartate transaminase (AST); alkaline phosphatase (ALP); lactate dehydrogenase (LDH); total bilirubin (TBIL) and gamma glutamyl transpeptidase (GGT).

Results. The comparison of LFTs on day 1, 7 and 14 revealed that plasma ALP, AST and LDH levels decreased on day 14 compared to day 1 (P ⫽ 0.03 and P ⫽ 0.02, P ⫽ 0.02 respectively). Total bilirubin levels did not show any change whereas GGT levels showed some elevation in comparison to day 1 levels (P ⫽ 0.03) (Table 1). Postoperatively, the ultrasonographic study of liver and gallbladder of 3 patients (5%) who underwent CABG procedure showed sludge and/ or calculi. Conclusion. After open heart surgery, in patients with congestive heart failure and low ejection fraction, prolonged nutritional support does not cause deterioration in the liver function tests. However, further investigation for detection of gallbladder dysfunction may be needed. O-76 Influence of thoracic epidural anaesthesia on haemodynamic changes Tadas Lenkutis, Edmundas Sirvinskas Lithuanian University of Health Sciences, Kaunas, Lithuania Introduction. Despite epidural anaesthesia alone and in combination with general anaesthesia having been widely applied already for many years in different surgery fields, its benefits in on-pump cardiac surgery is still under discussion [1]. Advantage of a thoracic epidural anaesthesia is purportedly clear with effective suppression of post-operative pain, stress and inflammatory reactions. However thoracic epidural anaesthesia directly influences the circulation causes haemodynamic instability and the patient’s need for an increased preload [2]. The aim of the study was to determine the impact of thoracic epidural anaesthesia on the cardiovascular system using a transpulmonary thermodilution technique, during on-pump surgery. Method. Sixty patients undergoing coronary artery bypass graft surgery were enrolled in the study. They were randomized into two groups: anaesthesia group (GA, n ⫽ 30) and epidural anaesthesia group (TEA, n ⫽30) having general anaesthesia with TEA. Haemodynamic monitoring was conducted using PiCCO system. Baseline measurements of SI, global end-diastolic volume index (GEDI), intrathoracic blood volume index (ITBVI) were recorded in all patients before fluid load. An iv. fluid load of 6 –7 ml/kg of Ringer’s lactate was infused to all patients before induction. In the TEA group, an epidural catheter was positioned in T1-T2 interspace. Lidocaine 2% 7– 8 ml was injected into epidural catheter and followed by an infusion of 0.25% bupivacaine 8-10 ml/h for 2 hours. Induction of general anaesthesia was the same in both groups. Anaesthesia was maintained with sevoflurane and iv. midazolam in both groups. Iv. fentanyl 10 –12 ␮g/kg was used as an analgesic component in the GA group and epidural bupivacaine infusion in the TEA group. Mean ABP was maintained in all patients between 50 and 75 mmHg by infusion of iv. fluids and by administration of vasoconstrictors. SI, ITBVI, and GEDI measurements were made before anaesthesia (baseline measurement), 20 min after start of surgery, 20 min, 60 min, 180 min, 600 min and 24 hr after cardiopulmonary bypass (CPB). Student’s t-test was used for comparison of the analysed variable averages and the data are presented as mean ⫾ EM. P⬍0.05 was considered statistically significant. Results. There were no significant differences in baseline in all measurements between two groups. During TEA, SI and GEDI were significantly higher at all points of measurement compared