Clinical question: Does the use of perioperative beta-blockers affect the outcomes in patients undergoing noncardiac surgery?
Bottom line: Determining the presence or absence of cardiac risk factors is important when deciding whether to use beta-blockers during the perioperative period for patients undergoing noncardiac surgery. This study shows that although perioperative beta-blockade may benefit patients with high cardiac risk, it increases short-term mortality in those with no cardiac risk factors. (LOE = 2b)
Reference: Friedell ML, Van Way CW, Freyberg RW, Almenoff PL. Beta-blockade and operative mortality in noncardiac surgery: harmful or helpful. JAMA Surg. 2015;150(7):658-663.
Study design: Cohort (retrospective)
Funding source: Unknown/not stated
Allocation: Uncertain
Setting: Inpatient (any location) with outpatient follow-up
Synopsis: Using data collected from the Veterans Health Administration, these investigators identified more than 325,000 patients hospitalized for surgery. The use of perioperative beta-blockers in this cohort was determined by using pharmacy data. It was unclear whether the beta-blocker was a new medication or a continuation of a home medication and the study did not measure if the beta-blocker was given preoperatively or postoperatively.
Each patient was assigned a cardiac risk score (1 point each for the presence of renal failure, coronary artery disease, diabetes, and abdominal/thoracic surgery) and grouped into 1 of 3 categories: 0 risk factors, 1 to 2 risk factors, and 3 to 4 risk factors. The results showed that the effect of the beta-blockers on mortality varied according to the presence of cardiac risk factors in patients undergoing noncardiac surgery (n = 314,114). In an adjusted analysis, patients with no cardiac risk factors who received beta-blockers had increased 30-day mortality compared with those who did not receive beta-blockers (odds ratio [OR] 1.19, 95% CI 1.06-1.35).
The opposite was true for patients with 3 to 4 cardiac risk factors: Those who received beta-blockers were less likely to die than those who did not receive them (OR 0.63, 95% CI 0.43-0.93). For patients with 1 to 2 risk factors, there was a nonsignificant reduction in mortality with the use of beta-blockers. For the minority of the cohort who actually underwent cardiac surgery (n = 12,375), there was no significant interaction seen between the number of cardiac risk factors and the use of beta-blockers on mortality. Of note, more than 90% of patients in this study population were men, thus these findings may not be generalizable to women.
Dr. Kulkarni is an assistant professor of hospital medicine at Northwestern University in Chicago.
