Outcomes of Perioperative β-Blockade in Patients Undergoing Noncardiac Surgery: A Meta-Analysis

Abstract

Background:

Several studies have evaluated the impact on myocardial infarction (MI), stroke, and overall mortality of perioperative β-blocker use in patients undergoing noncardiac surgery (NCS). However, most studies did not have adequate sample size and statistical power and were therefore underpowered to adequately evaluate these end points.

Objective:

To conduct a meta-analysis to determine the balance of benefits and harms associated with perioperative β-blocker use in NCS.

Methods:

A systematic literature search of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials was conducted from January 1960 through February 2009. Manual reference search was performed to identify additional relevant trials. Randomized, double-blinded, placebo-controlled trials comparing the use of β-blockars with placebo; using β-blockers perioperatively in β-blocker–naïve patients undergoing NCS; and evaluating endpoints of Ml, stroke, or all-cause mortality were included.

Results:

Six trials (N = 10,183) met our inclusion criteria. Perioperative β-blocker use was associated with a significant reduction in patients' odds of developing Ml (OR 0.74, 95% CI 0.61 to 0.89) but a significant increase in odds of developing stroke (OR 1.98, 95% CI 1.23 to 3.20) and also a nonsignificant increase in mortality (OR 1.21, 95% CI 0.98 to 1.49) versus placebo. Control-rate meta-regression determined that patients with highest baseline odds of stroke had decreased relative odds of having a stroke with a β-blocker versus placebo (β coefficient –0.97; 95% credible interval –1.04 to –0.90).

Conclusions:

When perioperative β-blockers are used in NCS patients, there is a trade-off between reduction in MI and increase in stroke, with a troubling trend toward an increase in mortality. Patients with lower baseline odds of developing stroke appear to be at greater risk of β-blockgr–induced stroke.