Intercurrent drug therapy and perioperative cardiovascular mortality in elective and urgent/emergency surgical patients

The Oxford Record Linkage Study (ORLS; an epidemiological database) was used to examine relationships between intercurrent cardiovascular drug therapy and cardiac death within 30 days of elective or emergency/urgent surgery under general anaesthesia. Cases identified from the ORLS were paired with matched control patients. Clinical details were obtained from the patients' medical notes. In elective surgical patients, there was no effect of beta -adrenoceptor or calcium entry channel blockade, diuretics or digoxin on cardiac death after adjusting for confounding variables. Use of nitrates was associated with an odds ratio of 4.79 [95% confidence interval (CI) 1.01-22.72] for cardiac death after adjustment for confounding by a history of angina and residual age difference. In emergency/urgent patients, there were significant univariate associations with cardiac death for intercurrent use of angiotensin converting enzyme (ACE) inhibitors (odds ratio 1.18) and diuretics (odds ratio 4.95; 95% CI 1.82-13.46). However, neither maintained significance after adjustment for the confounding effect of cardiac failure. We conclude that, with the possible exception of the use of nitrates in elective surgical patients, chronic intercurrent drug treatment alone does not significantly affect the odds of cardiac death within 30 days of surgery.