The effect of sedation on weaning following coronary artery bypass grafting: propofol versus oxycodone-thiopental

BACKGROUND: Propofol has been advocated for sedation in intensive care because of superior recovery characteristics. We hypothesised that the use of two totally different sedation methods after coronary artery bypass grafting should result in differences not only in extubation time, but also in breathing pattern and gas exchange during weaning and after extubation. METHODS: Thirty patients participated in this randomised and controlled study. We used propofol infusion and oxycodone-thiopental bolus dosage, titrated to sedation level 4 or 5 according to Ramsey. Weaning was performed using protocol-based pressure support trials. RESULTS: Total (SD) fentanyl dose during operation was 33 (6) microg x kg(-1) for propofol and 34 (6) microg x kg(-1) for oxycodone-thiopental (ns). The target sedation was achieved equally with both methods. The time from admission to intensive care unit to extubation was 494 (100) min for propofol and 521 (98) min for oxycodone-thiopental (ns). Weaning times were 63 (24) min and 112 (63) min in the propofol and oxycodone-thiopental groups, respectively (P<0.05). Breathing frequency increased and tidal volume decreased from weaning to 2 h postextubation. CONCLUSION: Propofol infusion and oxycodone-thiopental bolus dosages, titrated to the same sedation end point, resulted in similar time from admission to extubation, although the weaning period was shorter in the propofol group. In terms of breathing pattern, gas exchange, blood gases and haemodynamics, the methods were similar. Propofol, despite its attractive pharmacological profile, may offer no clinical benefit in short-term sedation after a moderate dose fentanyl anaesthesia in cardiac surgery.     

Cardiac outcome after sevoflurane versus propofol sedation following coronary bypass surgery: a pilot study

Background: Studies of volatile anesthetic administration during coronary artery bypass grafting (CABG) report reduced serum levels of post‐operative cardiac troponin‐T (cTnT). Our primary objective was to evaluate whether short‐term sedation with sevoflurane in the intensive care unit (ICU) – after CABG – could affect the release of cTnT, compared with propofol sedation. Methods: Following isolated CABG with cardiopulmonary bypass, 100 patients were randomized to either sevoflurane via the Anesthetic Conserving Device (AnaConDa^®) or propofol for ICU sedation. Study drugs were administered for 2 h during mechanical ventilation and thereafter until extubation criteria were met. The primary endpoint was cTnT 12 h post‐operatively. Crude cTnT data were not normally distributed and therefore compared with the Mann–Whitney U‐test. Because of the skewed pre‐operative and post‐operative cTnT data, we performed a post hoc analysis of the change in cTnT between pre‐operative values and 12 h post‐operatively. Results: There was no statistically significant difference between groups in the primary endpoint cTnT values at 12 h post‐operatively, cardiac events or the need for hemodynamic support. In the post hoc analysis, the cTnT increase from pre‐operative values to 12 h post‐operatively was less pronounced in the sevoflurane group (P=0.008). Conclusion: Post‐operative short‐term sevoflurane sedation following CABG, in comparison with propofol, did not affect the cTnT values at 12 h post‐operatively and clinical outcome was equal between groups. The result from the post hoc analysis, with less cTnT change over time, is nevertheless hypothesis‐generating and warrants a larger study.     

Health-related quality of life following off-pump versus on-pump coronary artery bypass grafting in elderly moderate to high-risk patients: a randomized trial.

OBJECTIVE: Previous trials comparing coronary artery bypass grafting (CABG) with or without extracorporeal circulation have mainly enrolled selected patients at younger age and low risk. Patient-reported health-related quality of life has not been significantly different. We compared health-related quality of life in elderly moderate to high-risk patients randomized to either off-pump or on-pump surgery. METHODS: The study is a sub-study of the randomized Best Bypass Surgery Trial that compares off-pump to on-pump treatment, with respect to peri- and postoperative mortality and morbidity in patients with a moderate to high-predicted preoperative risk. After randomization and before heart surgery, 120 consecutive patients were asked to fill in the Medical Outcomes Study Short Form 36 (SF-36) and Major Depression Inventory (MDI) diagnostic scale for self-report of health-related quality of life. Three months after surgery, the same questionnaires were mailed to the patients. RESULTS: The response rate was 96.5%. At baseline, the groups were comparable except for a difference in educational level. Both groups improved in all eight SF-36 domains from baseline to 3 months. No statistical differences were seen between the groups except for changes in mean difference of role limitation due to emotional problems, which was significantly (P=.04) improved in favour of the on-pump group. Depression scores remained unchanged within and between the two surgical groups. CONCLUSIONS: Both on-pump and off-pump patients improved in health-related quality of life scores after CABG surgery. No clinically relevant difference between the groups could be demonstrated.     

Endoscopic vs open saphenous vein harvest for coronary artery bypass grafting: a prospective randomized trial

OBJECTIVE: Endoscopic saphenous vein harvesting (EVH) for coronary artery bypass grafting (CABG) has been developed to reduce leg wound morbidity and improve patient satisfaction. Choosing between EVH of a short vein segment from the thigh and open venous harvesting (OVH) of a short segment from the calf represents a clinical dilemma as EVH is easiest to perform from the thigh and OVH is easiest to perform from the calf. The purpose of this study was to investigate whether leg wound morbidity was reduced after EVH of a short vein segment from the thigh compared with OVH from the calf. Secondly we investigated whether EVH would reduce length of hospital stay and improve cosmetic results. METHODS: From April 2004 to June 2007, 132 patients undergoing elective isolated CABG were randomized to have a short segment of saphenous vein harvested either by the EVH or OVH technique. Clinical follow-up was scheduled at day 5 and at 1 month. Primary end-points included wound morbidity. Secondary end-points included harvest time, length of hospital stay, cosmetic results and need for additional wound care after discharge. RESULTS: The groups were preoperative similar. Three patients in the OVH group were excluded from the study as it became apparent that it was necessary to extend the incision beyond the knee. Harvest time was longer for the EVH group, but these patients suffered from significantly fewer cases of infectious and non-infective wound complications, with a substantial reduction in the need for post-discharge leg wound care. The purulent infection rates in the EVH and OVH groups were 0% and 11%, respectively. The overall leg wound morbidity rates regarding cellulitis, purulent infection, dehiscence and skin necrosis were 3% and 27% in the EVH and OVH groups, respectively (p<0.001). The length of hospital stay was similar. The conversion rate from EVH to OVH was 14%. The EVH group experienced less pain and better cosmetic results. CONCLUSIONS: EVH of a short vein segment from the thigh results in less wound morbidity and better cosmetic results compared with OVH of a short vein segment from the calf.     

丙泊酚与异氟醚对冠状动脉旁路移植术患者心肌保护作用的比较:meta分析

目的 采用meta分析法比较丙泊酚与异氟醚对冠状动脉旁路移植术患者心肌的保护作用.方法 通过电子数据库检索比较丙泊酚与异氟醚对冠状动脉旁路移植术患者心肌保护作用的随机对照试验.由2位评价员独立检索、提取资料:患者一般情况,术前用药情况,麻醉诱导和维持时使用的麻醉药,术前和术后6、12、24、48 h时心肌肌钙蛋白Ⅰ(cTnI)浓度,术中正性肌力药物使用情况,术后24 h内心肌梗死发生情况.采用Cochrane协作网提供的Review Manager 5.0.2软件进行meta分析.结果 共16项研究符合纳入标准,共794例患者,其中丙泊酚组405例,异氟醚组389例.2组患者术后血浆cTnI浓度、术后24 h内心肌梗死发生率和术中正性肌力药使用率差异无统计学意义(P＞0.05).结论 丙泊酚与异氟醚对冠状动脉旁路移植术患者的心肌保护作用无差异.     

Stroke following coronary artery bypass grafting: a ten-year study

To identify possible risk factors for the occurrence of stroke during coronary artery bypass grafting (CABG), the cases of 3,279 consecutive patients having isolated CABG from 1974 to 1983 were reviewed. During this period, the risk of death fell from 3.9% to 2.6%. The stroke rate, however, fell initially but then rose from 0.57% in 1979 to 2.4% in 1983. Adjustment of these data for age clearly demonstrated that the risk of stroke has increased largely because of an increase in the mean age of patients undergoing CABG procedures. A case-control study involving all 56 stroke victims and 112 control patients was used to identify those risk factors significantly associated with the development of stroke in univariate analysis: increased age (63 versus 57 years in stroke patients and controls, respectively; p less than 0.0001); preexisting cerebrovascular disease (20% versus 8%; p less than 0.03); severe atherosclerosis of the ascending aorta (14% versus 3%; p less than 0.005); protracted cardiopulmonary bypass time (122 minutes versus 105 minutes; p less than 0.005); and severe perioperative hypotension (23% versus 4%; p less than 0.0001). Other variables not found to correlate with postoperative stroke included previous myocardial infarction, hypertension, diabetes mellitus, lower extremity vascular disease, preoperative left ventricular function, and intraoperative perfusion techniques. Elderly patients who have preexisting cerebrovascular disease or severe atherosclerosis of the ascending aorta or who require extensive revascularization procedures have a significantly increased risk of postoperative stroke.     

Isradipine for the treatment of hypertension following coronary artery bypass graft surgery: a randomized trial versus sodium nitroprusside.

In a randomized trial, a calcium antagonist, isradipine (ISR) and sodium nitroprusside (SNP) were compared in the management of hypertension in the early period following coronary artery bypass grafting (CABG). Patients with a mean arterial pressure (MAP) of greater than 100 mmHg were treated with a 6 h i.v. infusion of ISR (n = 98) or SNP (n = 100). Mean MAP at baseline was 113 (ISR) and 112 mmHg (SNP). Blood pressure control (MAP less than or equal to 90 mmHg within 25 min) was achieved in 92% (ISR) and 84% (SNP), within a mean of 12 and 15 min, respectively (P less than 0.01 between groups). At 25 min, mean percentage changes from baseline for ISR and SNP were: MAP -24.3% vs. -21.4% (P less than 0.05), heart rate +4.1% vs. +8.4% (P less than 0.01), rate-pressure-product -16.9% vs. -10.6% (P less than 0.001), cardiac index +19.2% vs. +4.6% (P less than 0.001), stroke volume index +16.1% vs. -1.9% (P less than 0.001), and peripheral vascular resistance -35.4% vs. -22.0%, (P less than 0.001). Treatment was discontinued before 6 h in 24 patients in each group because of low blood pressure. Hypotension (MAP less than 70 mmHg) and tachycardia were less frequent with ISR than with SNP. In conclusion, ISR is effective and well tolerated in the treatment of hypertension following CABG, and has a haemodynamic profile which may be more favourable than that seen after treatment with SNP.     

Influence of diabetes on mortality and morbidity: off-pump coronary artery bypass grafting versus coronary artery bypass grafting with cardiopulmonary bypass

BACKGROUND: Myocardial revascularization in diabetic patients is challenging with no established optimum treatment strategy. We reviewed our coronary artery bypass grafting experience to determine the impact of eliminating cardiopulmonary bypass on outcomes in diabetic patients relative to nondiabetic patients. METHODS: From January 1995 through December 1999, 9,965 patients, of whom 2,891 (29%) had diabetes, underwent isolated coronary artery bypass grafting. Diabetic and nondiabetic patients were further divided into groups on the basis of cardiopulmonary bypass use. Twelve percent (346 of 2,891) of diabetic patients and 12% (829 of 7,074) of nondiabetic patients underwent coronary artery bypass grafting without cardiopulmonary bypass; the remainder had coronary artery bypass grafting with cardiopulmonary bypass. Nineteen preoperative variables were compared among treatment groups by univariate analysis. RESULTS: Patients undergoing coronary artery bypass grafting without cardiopulmonary bypass compared with those having coronary artery bypass grafting with cardiopulmonary bypass had higher mean predicted mortalities (diabetic, 3.96% versus 3.72%, p = 0.83; nondiabetic, 3.03% versus 2.86%, p = 0.79). In nondiabetic patients, coronary artery bypass grafting without cardiopulmonary bypass provides an actual and risk-adjusted survival advantage over coronary artery bypass grafting with cardiopulmonary bypass (1.81% versus 3.44%, p = 0.0127; risk-adjusted mortality, 1.79% versus 3.61%, p = 0.007). This survival benefit of coronary artery bypass grafting without cardiopulmonary bypass was not seen in diabetic patients (2.89% versus 3.69%, p = 0.452; risk-adjusted mortality, 2.19% versus 2.98%, p = 0.42). Diabetic patients undergoing coronary artery bypass grafting without cardiopulmonary bypass had fewer complications, including decreased blood product use (34.39% versus 58.4%, p = 0.001), and reduced incidence of prolonged ventilation (6.94% versus 12.10%, p = 0.005), atrial fibrillation (15.90% versus 23.26%, p = 0.002), and renal failure requiring dialysis (0.87% versus 2.75%, p = 0.036). CONCLUSIONS: The survival advantage in nondiabetic patients treated with coronary artery bypass grafting without cardiopulmonary bypass is not apparent in diabetic patients. Coronary artery bypass grafting without cardiopulmonary bypass in diabetic patients is nevertheless associated with a significant reduction in morbidity.     

Composite arterial grafts versus conventional grafting for coronary artery bypass grafting

OBJECTIVES: Composite arterial grafts for coronary artery bypass grafting surgery allow complete arterial revascularization but are limited by the inflow of a single internal thoracic artery supplying all the grafted vessels. We reviewed the safety of composite arterial grafts using either bilateral internal thoracic arteries or a single internal thoracic artery and radial artery. METHODS: From January 1999 to July 2002, 402 consecutive patients receiving composite grafts only were compared to a control group of patients (n = 542) undergoing coronary artery bypass grafting with internal thoracic artery and saphenous veins operated upon by the same surgeons. Two different statistical approaches were used to compare groups in this retrospective analysis. First, propensity score analysis with greedy matching technique was used to match patients from each group. Second, a multivariate analysis was performed looking at a combined patient outcome of death, intra-aortic balloon counterpulsation utilization, myocardial infarction, stroke, and prolonged ventilation on all patients in both groups. RESULTS: After matching by propensity score, the major clinical outcomes in composite arterial (n = 249) and control (n = 249) groups were found to be similar. The in-hospital mortality in the composite group was 1.2% as compared with 0.4% in matched patients (P =.62). However, patients in the composite group were found to have a significantly longer pump time (P <.0001), longer clamp time (P <.0001), increased incidence of prolonged mechanical ventilation (12.8% vs 4.8%; P =.002), and higher incidence of combined morbidity outcome (13.6% vs 6.4%; P =.007) as compared with matched patients. Multivariable analysis showed that composite arterial grafting was an independent predictor of the combined morbidity outcome with an odds ratio of 2.1 (1.2-3.7). CONCLUSIONS: These findings suggest that composite arterial grafting may be associated with an increase in risk-adjusted patient morbidity when compared with a conventional coronary artery bypass grafting group, although a mortality difference was not demonstrable.     

Breast necrosis following coronary artery bypass grafting

We present a case of left breast necrosis following coronary artery bypass grafting which was misdiagnosed as a breast cancer. Breast necrosis after myocardial revascularization is an extremely rare complication of the surgical procedure using the most conventional graft which is the left internal mammary artery. The left internal mammary artery is the main blood supplying artery of the left breast.