Association of Cerebrovascular Injury and Secondary Vascular Insult With Poor Outcomes After Gunshot Wound to the Head in a Large Civilian Population.

BACKGROUND AND OBJECTIVES: Cerebrovascular injury (CVI) after civilian gunshot wound to the head (GSWH) likely contributes to poor outcomes, but little supporting evidence exists. The purpose of this study was to determine whether intracranial CVI from GSWH and secondary vascular insult (stroke or rehemorrhage) were associated with poor outcomes in a large civilian population. METHODS: This was a single-institution, retrospective cohort study on patients admitted between January 2014 and July 2022 at a large, metropolitan, level-1 trauma center. Multivariate regression models and propensity score matching were used. RESULTS: A total of 512 civilian patients presented with GSWH, and a cohort of 172 (33.5%) met inclusion criteria, with 143 (83.1%) males and a mean (SD) age of 34.3 (±14.2) years. The incidence of intracranial CVI was 50.6% (87/172 patients), and that of secondary vascular insult was 32.2% (28/172 patients). Bifrontal trajectories (adjusted odds ratio [aOR] 13.11; 95% CI 2.45-70.25; P = .003) and the number of lobes traversed by the projectile (aOR 3.18; CI 1.77-5.71; P < .001) were associated with increased odds of resultant CVI. Patients with CVI suffered higher rate of mortality (34% vs 20%; odds ratio [OR] 2.1; CI 0.78-5.85; P = .015) and were less likely to achieve a good functional outcome with a Glasgow Outcome Score of 4-5 (34% vs 68%; OR 0.24; CI 0.1-0.6; P = .004) at follow-up. Furthermore, patients with CVI and resultant secondary vascular insult had even worse functional outcomes (Glasgow Outcome Score 4-5, 16.7% vs 39.0%; aOR 0.012; CI 0.001-0.169, P = .001). CONCLUSION: Intracranial CVI from GSWH and associated secondary vascular insult are associated with poor outcomes. Given the high prevalence and potentially reversible nature of these secondary injuries, early screening with vascular imaging and treatment of underlying CVI may prove to be critical to improve outcomes by reducing stroke and rehemorrhage incidence.