Class of 2013 Abstract / Specific Aims: Guidelines developed by the Brain Trauma Foundation recommend the use of prophylactic anticonvulsants, particularly phenytoin, for the prevention of early posttraumatic seizures for patients with severe traumatic brain injuries. The purpose of this study is to evaluate the effectiveness of levetiracetam, a newer anticonvulsant, for posttraumatic seizure prevention in patients with severe traumatic brain injury. Methods: This study was approved by the University of Arizona Medical Center Institutional Review Board. The project consists of a retrospective cohort analysis from January 1, 2010 to September 30, 2011. We have abstracted data from all patients with traumatic brain injuries over this time period from the University of Arizona Medical Center Trauma Registry, and have matched these patients with their records in the pharmacy database to determine who received levetiracetam versus no prophylaxis. Patients younger than 18 years of age, pregnant women, patients who were deemed to be nonsalvageable, and patients who had a seizure prior to initiation of levetiracetam were excluded from the study. The following data was collected: age, gender, ethnicity, mechanism of injury, injury severity score, ED GCS, ED SBP, ED pulse, ED RR, blood alcohol level, ICU length of stay, number of ventilator days, hospital length of stay, FIM score at discharge (totals, and by component), diagnosis, surgery and complication type, anticonvulsant given, type of beta-blocker given, maximum and minimum dose used, cumulative doses given, and whether there exists a known prior history of anticonvulsant use. All data were recorded without patient identifiers and have been kept confidential. A multivariate logistic regression analysis was used to evaluate a relationship between other data collected from the patients’ medical records and seizure occurrence. Chi Square or Fisher's Exact test will be used in the final analysis to compare the effectiveness of levetiracetam versus no prophylaxis to prevent posttraumatic brain injury seizures. Significance is defined as p<0.05 for all analyses. Main Results: The results are pending the final data analysis. Conclusion: To be determined.