Background: Beta-adrenoreceptor blocker (beta-blocker) therapy may improve outcomes in surgical patients by decreasing cardiac oxygen consumption and hypermetabolism. Because beta-blockers can lower the systemic blood pressure and cerebral perfusion pressure, there is concern regarding their use in patients with head injury. However, beta-blockers may protect beta-receptor rich brain cells by attenuating cerebral oxygen consumption and metabolism. We hypothesized that beta-blockers are safe in trauma patients, even if they have suffered a significant head injury.
Methods: Using pharmacy and trauma registry data of a Level I trauma center, we identified a cohort of trauma patients who received beta-blockers during their hospital stay (beta-cohort). Trauma admissions who did not receive beta-blockers were in the control cohort. beta-blocker status, in combination with other variables associated with mortality, were placed in a stepwise multivariate logistic regression to identify independent predictors of fatal outcome.
Results: In all, 303 (7%) of 4,117 trauma patients received beta-blockers. In the beta-cohort, 45% of patients were on beta-blockers preinjury. The most common reason to initiate beta-blocker therapy was blood pressure (60%) and heart rate (20%) control. The overall mortality rate was 5.6% and head injury was considered to be the major cause of death. After adjusting for age, Injury Severity Scale score, blood pressure, Glasgow Coma Scale score, respiratory status, and mechanism of injury, the odds ratio for fatal outcome was 0.3 (p < 0.001) for beta-cohort as compared with control. Decreased risk of fatal outcome was more pronounced in patients with a significant head injury.
Conclusions: beta-blocker therapy is safe and may be beneficial in selected trauma patients with or without head injury. Further studies looking at beta-blocker therapy in trauma patients and their effect on cerebral metabolism are warranted.