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Introduction. Ventricular fibrillation accounts for 20% of the mortality after aortic valve replacement and the second most common cause of death. Several studies have shown reduction in the incidence of atrial fibrillation with prophylactic amiodarone. This study examines the role of amiodarone prophylaxis for ventricular arrhythmias during aortic valve replacement. Method. Thirty patients were randomly assigned to two groups; patients in the first group received 2.5 mg/kg of amiodarone immediately after induction of anaesthesia and central venous line insertion in the early bypass period, and the other group were control. The number of ventricular arrhythmias (defined as any episode of ventricular fibrillation, haemodynamically unstable ventricular tachycardia, or any ventricular tachycardia lasting more than 30 seconds), number of shocks and total energy for cardioversion, and length of ICU stay were recorded. Results. There were no differences in age, sex, ventricular function, cross-clamp time, or bypass time between the two groups. Four patients in the amiodarone group returned to spontaneous
sinus rhythm during separation from cardiopulmonary bypass compared to only 1 patient in the control group. The incidence of ventricular arrhythmias was 73.3% in the amiodarone group and 93.3% in the controls (11 vs. 14 patients, difference 20%), but statistical significance was not achieved (P⫽0.165). The patients in the amiodarone group responded to fewer cardioversion shocks (P⫽0.033) and needed less energy (P⫽0.013. No patients in the amiodarone group experienced any ventricular arrhythmias during the ICU period, while 5 patients in the control group did (P⫽0.021). Patients in the amiodarone group had an almost statistically significant shorter ICU stay (P⫽0.05). Discussion. Amiodarone decreased the incidence of ventricular arrhythmias postoperatively and improved the response to cardioversion. Although a trend was shown, larger studies are needed to establish the role of amiodarone for prevention of ventricular arrhythmias intraoperatively and reduction of ICU length of stay.
Best Poster Session P-09 Perioperative administration of fibrinogen is associated with increased risk of postoperative complications after cardiac surgery Lars Folkersen, Mariann Tang Jensen, Søren Påske Johnsen, Carl-Johan Jakobsen Aarhus University Hospital, Skejby, Aarhus, Denmark Introduction. Fibrinogen is a key factor in coagulation and is routinely used to reduce bleeding in patients undergoing cardiac surgery. However, fibrinogen may also potentially induce a risk for thrombosis and hypercoagulability. Method. We identified all patients undergoing cardiac surgery in our institution in 2008-09 from our Heart Registry (n⫽1877) and merged with our patient data management system to identify patients receiving fibrinogen, aprotinin and recombinant VIIa perioperatively. The outcomes considered included in-hospital MI, stroke and need for dialysis. Results. Independent risk factors for postoperative stroke were preoperative neurological dysfunction, valve- and aortic surgery and perioperative fibrinogen. The only significant risk factor for postoperative MI was preoperative ongoing ischaemia. Independent risk factors for dialysis were s-creatinine ⬎ 200 mol/L, age, general- and cardiac state (EuroSCORE) together with perioperative aprotinin and fibrinogen. Complication No. patients Stroke Myocardial infarction Need for dialysis
Factors Perioperative Aprotinin Recombinant VIIa Fibrinogen
Fibrinogen
None
175 11 (6.3%) 10 (5.7%) 25 (14.3%)
1,702 32 (1.9%) 47 (2.8%) 61 (3.6%)
Stroke Adjusted OR* (95%CI)
Myocardial infarction Adjusted OR* (95%CI)
Dialysis Adjusted OR* (95%CI)
1.11 (0.35-3.54) 0.75 (0.09-6.35) 2.68 (1.23-5.83)
1.27 (0.39-4.13) 1.05 (0.12-8.96) 1.78 (0.79-4.01)
3.50 (1.77-6.92) 0.84 (0.19-3.77) 4.08 (2.21-7.53)
*Adjusted for age, sex, residual patient factors, cardiac factors, neurological dysfunction, S-creatinine ⬎200 mol/L (all EuroSCORE definition), preop. platelet inhibitors, valve- and aortic surgery together with perioperative aprotinin, rVIIa and fibrinogen, which were mutually adjusted.
Discussion. Further studies are warranted to clarify whether association between postoperative complications and perioperative use of fibrinogen is casual. P-10 Thoracic paravertebral block for video-assisted thoracoscopic surgery: single injection versus multiple injection Fatma Nur Kaya, Selcan Bayraktar
Gurkan
Turker,
Elif
Basagan-Mogol,
Uludag University, School of Medicine Department of Anaesthesiology and Reanimation, Bursa, Turkey Introduction. Thoracic paravertebral blocks (PVB) have been shown to be effective for analgesia after video-assisted thoracoscopic surgery (VATS), both with single injection and multiple injection techniques [1,2]. However, no studies to date have compared the superiority of either technique. Thus, in this study, we compared the efficacy of single injection-PVB and multiple injection-PVB on postoperative analgesia in VATS. Method. After ethics committee approval and informed consent, 40 ASA I to III patients undergoing elective VATS were included in this prospective, randomized study. A nerve-stimulator guided PVB was performed using a solution of 20 ml 0.5% bupivacaine with 1:200,000 epinephrine either by a single injection at T6 (Group S, n⫽20) or by five injections of 4 ml each at T4 to T8 (Group M, n⫽20) in the sitting position before surgery. Results. A successful PVB was achieved in all patients. The times for block application were 6.2⫾0.8 min in the S group and 17.1⫾1.8 min in the M group (P⬍0.001). The times to block onset were 8.1⫾1.2 min in the S group and 7.4⫾0.9 min in the M group (P⬍0.05). The number of anaesthetized dermatomes were 6.7⫾0.9 for the S group and 5.9⫾1.2 for the M group (P⬎0.05). Postoperative pain scores both at rest and coughing, and morphine consumption with PCA were comparable in the two groups. The time to first analgesic requirement and pain score at this time were similar for both groups. There were no significant differences in times to the first mobilization and hospital discharge for two groups. Patient satisfaction with the analgesic procedure was greater in the S group (P⬍0.05). No complications were attributed to the blocks.
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Discussion. Single injection-PVB can be an alternative to multiple injection-PVB in VATS. Decreasing the number of injections required in this technique may increase patient comfort and decrease complication.
Department of Anaesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Gyeonggi-do, Republic of Korea
REFERENCES 1. Kaya FN, Turker G, Basagan-Mogol E, et al. Preoperative multiple-injection thoracic paravertebral blocks reduce postoperative pain and analgesic requirements after video-assisted thoracic surgery. J Cardiothorac Vasc Anesth 2006; 20: 639-43. 2. Vogt A, Steiger DS, Theurillat C, et al. Siingle-injection thoracic paravertebral block for postoperative pain treatment after thoracoscopic surgery. Br J Anaesth 2005; 95: 816-21.
Introduction. Paraplegia remains a devastating neurological complication of thoraco-abdominal aortic surgery. HMG-CoA reductase inhibitors, traditionally used as lipid-lowering agents, are demonstrated to protect against ischaemic injury. This study was designed to evaluate the effect of simvastatin on spinal cord ischaemic injury. Method. Rats were randomly assigned to one of three groups: sham group (n⫽12), control group (n⫽12), and simvastatin group (n⫽12): In the sham and control group, saline was administered orally for 5 days before surgery. In the simvastatin group, simvastatin (Zocor®, Merck, Whitehouse Station, USA) 10 mg/kg was administered orally for 5 days before ischaemia. Spinal cord ischaemia for 10 minutes and 30 seconds was induced using a balloon-tipped catheter placed on proximal descending aorta in the control group and simvastatin group. Body temperature was monitored with a rectal probe and maintained at 37.5°C. Neurologic function was assessed at 3 and 7 day after reperfusion using the motor deficit index (MDI; 0⫽normal, 6⫽complete paralysis). After the last neurological evaluation, histologic examination of the spinal cord was performed. MDI and the number of normal motor neurons were compared by the Kruskal-Wallis test, followed by a Mann-Whitney U test. Results. At post-reperfusion day 3, the simvastatin group showed significantly lower MDI compared to the control group; [2 (1-4) vs. 3 (2-6), simvastatin group vs. control group, respectively, P⫽0.016]. This trend was sustained at day 7; [2 (0-2) vs. 3 (2-4)], simvastatin group vs. control group, respectively; P⫽0.001]. Simvastatin group displayed a significantly higher number of normal motor neurons compared to control group [31.5 (6.3) vs. 20.5 (4.5), simvastatin group vs. control group, respectively; P⬍0.001]. However, compared to sham group, simvastatin group displayed fewer intact motor neurons [31.5 (6.3) vs. 38.2 (5.2), simvastatin vs. sham group; P⫽007]. Discussion. Pretreatment with simvastatin 10 mg/kg, given orally for 5 days before ischaemic insult, improved the neurological outcome and resulted in more normal motor neurons in a rat model of spinal cord ischaemia.
P-11 Prognostic implications of the preoperative left ventricular diastolic dysfunction as assessed by E/e= in patients undergoing off-pump coronary artery surgery Eun-Ho Lee, In-Cheol Choi, Ji-Yeon Kim Asan Medical Center, Seoul, Republic of Korea Introduction. The ratio of the early transmitral flow velocity to the early diastolic velocity of the mitral annulus (E/e=) correlates with the left ventricular (LV) filling pressure and is, therefore, an indicator of diastolic function. We evaluated the prognostic implications of the E/e= ratio obtained by preoperative transthoracic echocardiography in patients undergoing off-pump coronary artery bypass graft surgery (OPCAB). Method. This observational study investigated 1,048 consecutive, adult patients undergoing non-emergency OPCAB. The primary outcome was the occurrence of major adverse cardiac events (MACE), defined as a composite outcome of death, myocardial infarction, stroke, malignant ventricular arrhythmia, cardiac dysfunction, or need for repeat revascularization. Patients were divided into four groups according to left ventricular ejection fraction (LVEF) and E/e=. LVEF ⬍50% was considered abnormal systolic function and E/e= ⬎15 was considered abnormal diastolic function. Logistic regression and survival analyses were performed. Results. Isolated LV diastolic dysfunction and combined LV systolic and diastolic dysfunction were associated with 30-day MACE (odds ratio [OR] 2.0, 95% confidence interval [CI] 1.1-3.6, P ⫽ 0.018 and OR 2.7, 95% CI 1.3–5.5, P ⫽ 0.006, respectively) and 1-yr MACE (hazard ratio [HR] 1.8, 95% CI 1.1–3.0, P ⫽ 0.013 and HR 2.5, 95% CI 1.4 – 4.3, P ⫽ 0.001, respectively). The MACE free 1-yr survival rate was significantly lower in patients with isolated LV diastolic dysfunction (P ⫽ 0.017) and combined LV systolic and diastolic dysfunction (P ⬍0.001) than in patients with normal LV function. Conclusions. LV diastolic dysfunction, as assessed by the E/e= ratio, is an independent predictor of 30-day and 1-yr MACE in patients who undergo elective OPCAB. These findings indicate that preoperative risk stratification in these patients should include assessment of their diastolic function. P-12 Pretreatment with simvastatin attenuates spinal cord ischaemic injury in an experimental spinal cord ischaemia model JinYoung Hwang, SungHee Han, SeongJoo Park
P-13 The impact of an online simulation of a TEE exam on learning to navigate the twenty standard views Massimilliano Meineri, Annette Vegas, Angela Michael Corrin, Candice Silversides, Gordon Tait
Jerath,
Toronto General Hospital, University of Toronto, Toronto, Canada
Introduction. A significant challenge in transoesophageal echocardiography (TOE) training is learning to navigate between the 20 standard diagnostic views. The limited availability and cost of full-scale high fidelity TOE simulators means trainees must practice on patients. We developed an online TOE simulator (http://pie.med.utoronto.ca/TEE/http://pie.med.utoronto. ca/TEE/). By selecting a view from a diagram the user can navigate between the 20 standard views, observing the probe and ultrasound beam movements on a 3D heart model with the corresponding TOE recording.