Air Versus Ground Transportation in Isolated Severe Head Trauma: A National Trauma Data Bank Study

Background: The effect of prehospital helicopter emergency medical services (HEMS) on mortality has been analyzed previously in polytrauma patients with discordant results.

Objective: Our aim was to compare outcomes in patients with isolated severe blunt traumatic brain injuries (TBIs) transported by HEMS or ground emergency medical services (GEMS).

Methods: We conducted a National Trauma Data Bank study (2007-2014). All adult patients (≥16 years old) who sustained an isolated severe blunt TBI and were transported by HEMS or GEMS were included in the study.

Results: There were 145,559 patients who met the inclusion criteria. Overall, 116,391 (80%) patients were transported via GEMS and 29,168 (20%) via HEMS. Median transportation time was longer for HEMS patients (41 vs. 25 min; p < 0.001). HEMS patients were more likely to have hypotension (2.7% vs. 1.5%; p < 0.001), Glasgow Coma Scale (GCS) score < 9 (38.2% vs. 10.9%; p < 0.001), and head Abbreviation Injury Scale (AIS) score of 5 (20.1% vs. 9.7%; p < 0.001). Stepwise logistic regression analysis identified age ≥ 65 years old, male sex, hypotension, GCS score < 9, prehospital intubation, and head AIS scores 4 and 5 as independent predictors of mortality. Helicopter transportation was independently associated with improved survival (odds ratio [OR] 0.55; 95% confidence interval [CI] 0.47-0.67; p < 0.001). Admission to a Level I trauma center was an independent predictor of survival (OR 0.64; 95% CI 0.53-0.82; p = 0.001). Regardless of head AIS, helicopter transport was an independent predictor of survival (AIS 3: OR 0.35; p < 0.001; AIS 4: OR 0.44; p < 0.001; AIS 5: OR 0.76; p < 0.001). A prolonged transport time was not an independent predictor of mortality.

Conclusions: Helicopter transport, in adult patients with isolated severe TBI, is associated with improved survival.