Intraoperative Hypotension and Perioperative Ischemic Stroke after General Surgery

Background: Postoperative stroke is a rare but major complication after surgery. The most often proposed mechanism is an embolus originating from the heart or great vessels. The roleofintraoperativehypotensionintheoccurrenceandevolution of postoperative stroke is largely unknown. Methods: A case-control study was conducted among 48,241 patients who underwent noncardiac and nonneurosurgical procedures in the period from January 2002 to June 2009.Atotalof42strokecases(0.09%)werematchedonage and type of surgery to 252 control patients. Conditional logistic regression analysis was used to estimate the effect of the duration of intraoperative hypotension (defined accordingtoarangeofbloodpressurethresholds)ontheoccurrence of an ischemic stroke within 10 days after surgery, adjusted for potential confounding factors. Results: After correction for potential confounders and multiple testing, the duration that the mean blood pressure was decreased more than 30% from baseline remained statistically significantly associated with the occurrence of a postoperative stroke. Conclusions: Intraoperative hypotension might play a role in the development of postoperative ischemic stroke. Especially for mean blood pressure values decreasing more than 30% from baseline blood pressure, an association with postoperative ischemic stroke risks was observed.