Early mortality after 2,902 coronary artery bypass operations

Comparison of three anesthetic techniques for off-pump coronary artery bypass grafting: General anesthesia, combined general and high thoracic epidural anesthesia, or high thoracic epidural anesthesia alone

OBJECTIVE

This study compared general anesthesia (GA), combined GA plus thoracic epidural anesthesia (TEA), and TEA alone in patients scheduled for off-pump coronary artery bypass grafting.

DESIGN

Prospective, nonrandomized clinical study

SETTING

University hospital.

PARTICIPANTS

Ninety consenting patients undergoing beating-heart coronary artery revascularization with comparable coronary status and left ventricular function.

INTERVENTIONS

GA (n=30) was conducted with propofol, remifentanil, and cisatracurium or combined with TEA (GA+TEA, n=30) or TEA as the sole anesthetic with ropivacaine plus sufentanil (TEA, n=30).

MEASUREMENTS AND MAIN RESULTS

Groups were comparable regarding the surgical approaches and the number of anastomoses. Four patients (GA, n=2; GA+TEA, n=2) who required unplanned cardiopulmonary bypass, and 4 patients in the TEA group who underwent unexpected intubation because of pneumothorax (n=2), phrenic nerve palsy, or incomplete analgesia were excluded from further analysis. Intraoperative heart rate decreased significantly with both GA+TEA and TEA. None of the patients with TEA alone was admitted to the intensive care unit, they all were monitored on average for 6 hours postoperatively in the intermediate care unit and allowed to eat and drink as desired on admission. Postoperative pain scores were lower in both groups with TEA. There were no differences among groups in patients overall satisfaction.

CONCLUSION

Based on the authors data, all anesthetic techniques were equally safe from the clinicians standpoint. However, GA+TEA appeared to be most comprehensive, allowing for revascularization of any coronary artery, providing good hemodynamic stability and reliable postoperative pain relief. Nonetheless, the actual and potential risks of TEA during cardiac surgery should not be underestimated.

Intraoperative local fibrinolysis as emergency therapy after early coronary artery bypass thrombosis

OBJECTIVE

Acute graft occlusion early postoperatively after coronary artery bypass grafting (CABG) is a rare but dramatic complication, frequently making resuscitation necessary. Emergency reoperation with reanastomosing of the concerning grafts is the normal procedure to restrict the otherwise unavoidable myocardial damage. Mortality in these cases is up to 50%. Due to this unsatisfying situation, we perform since 1995 in such cases an adjuvant intraoperative intracoronary installed fibrinolysis with recombinant tissue type plasminogen activator (rt-PA; alteplase).

METHODS

Between 1/1994 and 8/1998, 4231 patients underwent CABG. In 18 of these patients, emergency reoperation within the first 12 h after CABG due to clinical signs of acute myocardial infarction was necessary. In nine of the patients (group II) additionally intraoperative rt-PA lysis of the involved vessel/s has been performed. When the peripheral anastomosis was reopened and the thrombotic material was removed, we inserted for this a left atrial-catheter (LA-catheter) of 1.2 mm in diameter, into the coronary artery. Then we administered within 3-5 min, up to 100 mg rt-PA (t1/2: 5-9 min.) locally into the vessel. All patients were treated postoperatively with acetylsalicyl acid (ASA) and heparine.

RESULTS

In group I (n = 9; seven males, two females) without thrombolytic therapy, 78% of the patients (n = 7) could not have been prevented from large myocardial infarction despite emergency reoperation. Three of these patients died during or early after reintervention. In group II with fibrinolytic therapy (n = 9) three of the patients developed Q-wave myocardial infarction following reoperation. None of the patients died. Creatinkinase maximum were in group I significantly higher than in group II (group I: CK = 1254 units/I, CK-MB = 197 units/l; group II: CK = 502 units/l, CK-MB = 61 units/l; P < 0.01). Postoperative bleeding was considerable elevated in both groups. In group I, 832 ml/24 h (375-1420 ml), in group II 1164 ml/24 h (520-1560 ml). Lysis-associated complications were not observed.

CONCLUSIONS

Reoperation of patients with acute thrombotic bypass occlusion after CABG is characterized by a high mortality and morbidity. If additionally fibrinolysis is performed, a sufficient myocardial perfusion seems to be restored. A short half-life in combination with the presented non-systemic application technique of rt-PA seem to prevent unpredictable bleeding. Rt-PA lysis apparently contributes very effectively to the restoration of the macro- and microcirculation within the infarct-related area. Thrombolytic therapy during cardiac surgery with rt-PA is feasible, its application easy and harmful complications are not seen.

Coronary artery bypass surgery in women and in men; early and long-term results. A study of the Norwegian population adjusted by age and sex

OBJECTIVE

We wished to analyse early mortality, postoperative low-output syndrome needing intra-aortic balloon pumping support (IABP), total mortality, recurrent angina pectoris and total non-fatal myocardial infarction in women compared with men. Also, the standard mortality ratio (SMR) was estimated to compare the mortality data to the general Norwegian population of comparable sex and age.

METHODS

A total of 1025 patients; 113 women and 912 men, were submitted to coronary artery bypass surgery at Rikshospitalet, Oslo between August 1982 and December 1986. The patients were followed up until the 1st of January 1993, representing a mean follow-up time of 7.4 years. An exposed/non-exposed cohort study design was used. A power study was carried out. The standardized mortality ratios for women and men were calculated after adjusting for age and sex.

RESULTS

Crude odds ratio (ORC) of early mortality was 2.0 with a 95% confidence limit (CL95%) of 0.7-5.4. Odds ratio of low output syndrome needing intra-aortic balloon support was 1.7 (CL95% = 0.8-4.2). Statistical significance was not achieved for these end-points. Women did not run an increased hazard of total mortality (ORC = 0.9; CL95% = 0.5-1.5), recurrent angina pectoris (ORC = 1.4; CL95% = 0.8-2.4) or of total non-fatal myocardial infarction (ORC = 0.8; CL95% = 0.4-1.6) when compared with men. Adjusting for confounders did not significantly alter the results. When matched on sex and age and compared to the normal Norwegian population, we found an increased SMR in both men (2.5; CL95% = 2.2-2.9) and women (4.1; CL95% = 2.2-4.9).

CONCLUSION

The risk of early mortality and low-output syndrome needing intra-aortic balloon support tended to be higher in women compared with men. Women did not run an increased risk of total mortality, recurrent angina or of total non-fatal myocardial infarction. The standard mortality ratio was increased in both men and women, but in particular higher in women, suggesting a more aggressive course of coronary artery disease in operated women than in operated men. However, this difference did not show in the long term follow-up, due to the beneficial effect of coronary artery bypass surgery in both men and women.

Intraoperative blood transfusion is a major risk factor for coronary artery bypass grafting in women

BACKGROUND

Women have been found to have greater mortality from coronary artery bypass grafting than men. Uncertainty exists regarding the causes of the differences in outcomes between men and women after coronary artery bypass grafting.

METHODS

From a database of 2,569 patients having coronary bypass grafting we have determined factors that contribute to poorer outcomes in women compared with men.

RESULTS

Women were found to have greater mortality, postoperative bleeding, and postoperative pulmonary failure than men (p < 0.05). There was no significant difference between men and women in postoperative renal failure, postoperative infection, postoperative stroke, or intraaortic balloon pump (p = not significant). Patient factors other than sex accounted for all the significant predictors (stepwise logistic regression) of mortality, postoperative bleeding, postoperative renal failure, postoperative pulmonary failure, postoperative stroke, need for intraaortic balloon pump, and postoperative infection (p < 0.05). Poorer outcomes in women are associated with greater need for transfusion during operation. Diabetes is predictive of renal failure and stroke.

CONCLUSIONS

Mortality and morbidity is less in men despite their higher preoperative creatinine level, greater incidence of reoperation, lower ejection fraction, and more common atherosclerosis of the ascending aorta.

Differences between men and women in hospital mortality associated with coronary artery bypass graft surgery. The Northern New England Cardiovascular Disease Study Group

BACKGROUND

A prospective study of patients undergoing coronary artery bypass graft surgery (CABG) was conducted to examine differences in hospital mortality by sex. Outcome data on 3055 CABG patients undergoing operation between 1987 and 1989 were examined for differences in patient, disease, and treatment factors.

METHODS AND RESULTS

Odds ratios (OR), risk differences, and 95% confidence intervals (CI95%) were calculated. Mortality rates for women (7.1%) and men (3.3%) differed, the OR (women versus men) being 2.23 (CI95%, 1.58 to 3.15). Women were older, more often diabetic, and had more urgent or emergent surgery; adjustment yielded an OR (women versus men) of 1.75 (CI95%, 1.17 to 2.63). Body surface area (BSA) was associated with risk of death in both sexes (P = .007) and positively associated with coronary artery luminal diameters. After adjustment for BSA, sex was no longer significantly associated with mortality (OR [women versus men] of 1.18; CI95%, 0.72 to 1.95). Internal mammary artery (IMA) grafting was performed less frequently among women than men (64.8% versus 78.4%, P < .001). Smaller BSA and absence of IMA grafting were each associated with increased risk of death (RD) from heart failure. Risk of death from heart failure (RD [women minus men] = 2.05; CI95%, 0.89 to 3.22) and hemorrhage (RD [women minus men] = 0.63; CI95%, 0.13 to 1.13) was greater among women; these accounted for 71.1% of the sex-specific difference in mortality rates.

CONCLUSIONS

Excess risk of hospital mortality among women having CABG was largely the consequence of death from heart failure and, to a lesser extent, from hemorrhage. Smaller BSA (probably because of its association with coronary artery luminal diameter) and the absence of IMA grafting were each associated with increased risk of death from heart failure.