B. Zangbar1, P. Rhee1, B. Joseph1, N. Kulvatunyou1, I. Ibrahim-zada1, A. Tang1, G. Vercruysse1, R. S. Friese1, T. O’keeffe1 1University Of Arizona,Trauma/Surgery/Medicine,Tucson, AZ, USA
Introduction: Multiple prior studies have suggested an association between survival and beta-blocker administration in patients with severe traumatic brain injury (TBI). However, it is unknown whether this benefit of beta-blockers is dependent on heart rate control. The aim of this study was to assess whether rate control affects survival in patients receiving metoprolol with severe TBI.
Methods: We performed a 7-year retrospective analysis of all blunt TBI patients at a level 1 trauma center. Patients >16 years of age with head abbreviated injury scale (AIS) 4 or 5 who were admitted to the ICU from operating room (OR) or emergency room (ER) were included. Patients were stratified into two groups: metoprolol (BB) and no beta-blockers (NBB). Using propensity score matching we matched the patients in two groups in a 1:1 ratio controlling for age, gender, race, admission vital signs, Glasgow coma scale (GCS), injury severity score (ISS), average heart rate monitored during ICU admission, and standard deviation of heart rate during the ICU admission. Our primary outcome measure was survival.
Results: Overall 914 patients met inclusion criteria, of whom 189 received beta-blockers. A propensity-matched cohort of 356 patients (178: BB and 178: NBB) was included, which is shown below. Patients receiving Metoprolol had higher survival than patients who did not receive beta-blockers, despite no difference in mean heart rate and heart rate variability.
Conclusion: Our study shows an association with improved survival in patients with severe TBI receiving Metoprolol, and this effect appears to be independent of any reduction in heart rate. We suggest that Metoprolol should be administered to all severe TBI patients irregardless of any perceived beta-blockade effect on heart rate.