Do prolonged primary transport times for traumatic brain injury patients result in deteriorating physiology? A cohort study

Recent interest has focused on reorganizing emergency medical services (EMS) for traumatic brain injury (TBI) patients, with bypass of nonspecialist hospitals and direct transportation to distant neuroscience centers. Although this could expedite neurosurgery and neurocritical care, deteriorating physiology could be deleterious.We performed a multicenter cohort study examining adult patients with significant TBI enrolled in the English National Trauma Registry. The distributions and correlation of first recorded prehospital and emergency department (ED) vital signs were compared, and the effect of time on changes in vital signs was examined in bivariate and multivariate analyses.A total of 7149 eligible patients were studied. No clinically significant differences were apparent between distributions of prehospital and ED vital signs. Moderate linear correlation was observed for field and ED pulse rate (r(2) = 0.34) and GCS values (Spearman's rho = 0.76), with weak correlation apparent for systolic blood pressure (r(2) = 0.28) and respiratory rate (r(2) = 0.28). Eight percent of cases' vital signs deteriorated in the prehospital interval; however, odds of deterioration in vital sign status did not vary significantly with duration of EMS interval.The similarity between prehospital and ED vital signs, and lack of association between EMS interval and physiological deterioration, may support a strategy of direct transportation of TBI cases to specialist centers. Further research is necessary to identify patients at risk from deterioration during bypass and to investigate effects on mortality.