[Hypoxic brain damage in victims of fatal road traffic accident: prevalence, distribution and association with survival time and other head and extracranial injuries].

Objective: To describe the prevalence and distribution of hypoxic brain damage and its association with survival time and other head and extracranial injuries.

Method: A macro and microscopical study of brain lesions in 120 victims of fatal road traffic accident, independent of the survival time, was made. The patients were autopsied in the Instituto Médico Legal de Minas Gerais, in Belo Horizonte, from 1989 to 1993. The study was prospective and the individuals were randomly chosen.

Results: The 120 victims had sustained either a motor vehicle accident (51) or an auto-pedestrian injury (69). Eighty-three patients (69.2%) died instantaneously or survived less than 24 hours and 37 (30.8%) survived one or more days. Hypoxic brain damage occurred in 23 (19.2%) of the 120 brains. The prevalence was of 4.8% among the patients that survived less than 24 hours and of 51.4% for those with one or more days of survival. Hypoxic brain damage was found mainly in the hippocampus and subiculum (65.2%), thalamus (34.8%), cerebral neocortex (26.1%) and basal ganglia (21.7%). There was no significant association between hypoxic brain damage and increased intracranial pressure, thoracic-abdominal trauma and pneumonia and/or meningitis in the patients who survived one or more days.

Conclusion: Hypoxic brain damage occurred in high frequency in fatal victims of road traffic accident that survived one or more days, not being significantly associated with increased intracranial pressure, thoracic-abdominal trauma and pneumonia and/or meningitis.