Beta-adrenoreceptor blocker (β-blocker) therapy may improve outcomes in surgical patients by decreasing cardiac oxygen consumption and hypermetabolism. Because β-blockers can lower the systemic blood pressure and cerebral perfusion pressure, there is concern regarding their use in patients with head injury. However, β-blockers may protect β-receptor rich brain cells by attenuating cerebral oxygen consumption and metabolism. We hypothesized that β-blockers are safe in trauma patients, even if they have suffered a significant head injury.
Using pharmacy and trauma registry data of a Level I trauma center, we identified a cohort of trauma patients who received β-blockers during their hospital stay (β-cohort). Trauma admissions who did not receive β-blockers were in the control cohort. β-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.
In all, 303 (7%) of 4,117 trauma patients received β-blockers. In the β-cohort, 45% of patients were on β-blockers preinjury. The most common reason to initiate β-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 β-cohort as compared with control. Decreased risk of fatal outcome was more pronounced in patients with a significant head injury.
β-blocker therapy is safe and may be beneficial in selected trauma patients with or without head injury. Further studies looking at β-blocker therapy in trauma patients and their effect on cerebral metabolism are warranted.
From the Department of Surgery, University of Michigan, Ann Arbor, MI (E.M.C., M.R.H., M.B., M.D., K.S.A., K.I., W.L.W.); Department of Surgery, Hannover Medical School, Hannover, Germany (A.D.N.); and Harborview Medical Center, University of Washington, Seattle, WA (S.A.).
Submitted for publication August 20, 2006.
Accepted for publication October 31, 2006.
Presented at the 65th Annual Meeting of the American Association for the Surgery of Trauma, September 28–30, 2006, New Orleans, Louisiana.
Address for reprints: Saman Arbabi, MD, MPH, Harborview Medical Center, 325 Ninth Ave, Box 359796, Seattle, WA 98104; email: email@example.com.