Phenobarbital as Anticonvulsant Prophylaxis in Patients With Traumatic Brain Injury at Risk for Alcohol Withdrawal Syndrome

Abstract

Background: Anticonvulsant prophylaxis (ACP) for early post-traumatic seizures (PTS) is recommended in patients with traumatic brain injury (TBI). Phenobarbital (PB) may be used to prevent alcohol withdrawal syndrome (AWS) in at-risk patients. The dual-purpose use of PB in the TBI population would allow for consolidation of pharmacotherapy. Objective: The primary objective of this study was to determine the frequency of early PTS in TBI patients at risk of AWS treated with PB as ACP. Secondary objectives included determining rates of over sedation and endotracheal intubation. Methods: Patients received an intravenous (IV) loading dose of PB at 15-20 mg/kg followed by 1 mg/kg every 12 hours for 7 days with a goal level of 15-20 mcg/mL. Medication data, seizure frequency, and episodes of over sedation and endotracheal intubation were collected. Results: Eighty patients were treated with PB over a 1-year period. Thirty-nine patients were analyzed. Median loading dose was 19.9 (Interquartile Range 19.1-20.0) mg/kg with a median post load level of 21.7 mcg/mL (IQR 18.3-25.8) mcg/mL. One patient (2.6%) had electrographic evidence for early PTS. PB was discontinued in 4 (10.3%) patients out of concern for over sedation. One patient required endotracheal intubation after rapid PB loading. Conclusion: The frequency of early PTS was low when PB was used as primary ACP in patients with TBI at risk for AWS. Over sedation is a potential adverse effect that should be considered in the choice of ACP. No conclusions can be drawn as to the effectiveness of PB in preventing AWS.