Functional outcome after blunt and penetrating carotid artery injuries: analysis of the National Trauma Data Bank

BACKGROUND: We analyzed the functional outcome at discharge among a cohort of patients suffering traumatic carotid arterial injury (CAI) and compared them with matched controls. METHODS: CAI were identified by International Classification of Diseases-9 codes from the National Trauma Data Bank. Control groups were matched by age, mechanism, head Abbreviated Injury Scale score, Injury Severity Score, base deficit, and admission Glasgow Coma Scale score. Outcome was assessed using the functional independence measure (FIM) score for feeding, locomotion, and expression. FIM scores for each category ranged from 1 (full assistance required) to 4 (fully independent), with a maximum total FIM score of 12 representing full independence. RESULTS: There were 967 CAI identified among 474,024 patients for an overall incidence of 0.2%. The mechanism of injury was blunt in 570 (59%) and penetrating in 397 (41%) patients. Seventy-eight percent of penetrating CAI patients were fully independent for locomotion at discharge (FIM = 4) compared with only 37% of blunt patients (p < 0.01). Compared with the control group of similarly injured patients without carotid injury (n = 14,119), the blunt CAI group demonstrated more severe functional disability (FIM < or = 2) at discharge for feeding, expression, and locomotion. Fifty-five percent of blunt control patients were discharged fully independent (FIM total = 12) compared with only 33% of blunt CAI (odds ratio= 2.5; p < 0.01). The penetrating CAI group showed no significant difference in severe disability for feeding, expression, or locomotion compared with controls. However, 80% of penetrating control patients were discharged fully independent (FIM total = 12) compared with only 67% of patients with penetrating CAI (odds ratio = 2.0; p = 0.01). CONCLUSION: Blunt CAI is associated with more severe functional disability at discharge than penetrating CAI. Even when compared with a similarly injured control group, blunt CAI results in significant additional severe functional disabilities in feeding, expression, and locomotion.