Background. Despite the continuing improvements in surgical and cardiopulmonary bypass techniques during cardiac surgery, stroke remains a devastating complication. This study aimed to identify the preoperative and intraoperative risk factors for developing a perioperative stroke in patients undergoing coronary artery bypass graft surgery on cardiopulmonary bypass. Methods. A total of 4,380 consecutive patients who received isolated coronary artery grafting on cardiopulmonary bypass between 1992 and 2002 were included. The sample contained three cardiopulmonary bypass temperature strategies: hypothermic (< 31 degrees C, n = 1,853), tepid (32-35 degrees C, n = 1,088), and normothermic (> 36 degrees C, n = 1,439). Outcome measures reported include stroke incidence, 30-day mortality, and hospital length of stay. Results. The incidence of stroke was 1.2% (n = 51). Stroke patients were older, were more likely to be diabetic, hypertensive, have creatinine levels greater than 0.12 mmol/L, and have a history of stroke than those who did not have stroke (p < 0.05). Multivariate logistic regressions identified diabetes (p = 0.01), history of stroke (P = 0.04), and older age (p = 0.05) as independent predictors of stroke for all patients. The 30-day mortality for stroke patients was ten times greater than that of those who did not suffer stroke (17.6 vs 1.7%). Conclusions. Diabetes, history of stroke, and older age were identified as risk factors for stroke after coronary bypass; the temperature at which cardiopulmonary bypass was performed was not significant.
