Abstract
Objective: The authors retrospectively investigated prognostic factors for severe isolated head trauma in patients evacuated by a physician-staffed helicopter emergency medical service (HEMS) or ground ambulance using data from the Japan Trauma Data Bank (JTDB). Patients and Methods: This study was a retrospective analysis of data housed in the JTDB database. The study period was from January 2004 to May 2019. Subjects were divided into two groups according to the method of transportation: helicopter (i.e., HEMS), which included patients transported by a physician-staffed helicopter; and ambulance, which included patients transported by ground ambulance. Results: A total of 41,358 patients were enrolled in the study, including 2,029 in the helicopter group and 39,329 in the ambulance group. The ratio of males, median head Abbreviated Injury Scale and Injury Severity Scale (ISS) scores were significantly greater in the helicopter group than in the ambulance group, while the average age, median Glasgow Coma Scale, average Revised Trauma Score (RTS), and survival rate were significantly lower in the helicopter group than in the ambulance group. Of the variables that demonstrated statistical significance in the univariate analysis and classification of transportation and included in the multivariate analysis, the following were identified as significant predictors of survival outcomes: younger age, lower ISS, female sex, and greater RTS. HEMS was not a significant predictor of survival. Conclusion: The present study revealed no effect of HEMS transport on the outcomes of patients who experienced severe isolated head trauma compared with ground ambulance transportation. Further prospective studies, including an analysis of the operation time or distance traveled by the HEMS and the functional outcome(s) of patients with severe head injury transported by HEMS, are warranted.