Beta-Blocking Agents for Surgery: Influence on Mortality and Major Outcomes. A Meta-Analysis

ObjectiveTo re-evaluate the effects of perioperative beta-blockade on mortality and major outcomes after surgery.DesignA meta-analysis of parallel randomized, controlled trials published in English.SettingA university-based electronic search.ParticipantsPatients undergoing surgery.InterventionsTwo interventions were evaluated: (1) Stopping or continuing a β-blocker in patients on long-term β-blocker therapy; and (2) Adding a β-blocker for the perioperative period.Measurements and Main ResultsStopping a β-blocker before the surgery did not change the risk of myocardial infarction (3 studies including 97 patients): risk ratio (RR), 1.08 (95% confidence interval 0.30, 3.95); I2, 0%. Adding a β-blocker reduced the risk of death at 1 year: RR, 0.56 (0.31, 0.99); I2, 0%; p = 0.046; number needed to treat 28 (19, 369) (4 studies with 781 patients). Adding a β-blocker reduced the 0-to-30 day risk of myocardial infarction: RR, 0.65 (0.47, 0.88); I2, 12.9%; p = 0.006 (15 studies with 12,224 patients), but increased the risk of a stroke: RR, 2.18 (1.40, 3.38); I2, 0%; p = 0.001 (8 studies with 11,737 patients); number needed to harm 177 (512, 88).Conclusionsβ-blockers reduced the 1-year risk of death, and this effect seemed greater than the risk of inducing a stroke.