The Battalion Aid Station-The Forgotten Frontier of the Army Health System During the Global War on Terrorism.

BACKGROUND The battalion aid station (BAS) has historically served as the first stop during which combat casualties would receive care beyond a combat medic. Since the conflicts in Iraq and Afghanistan, many combat casualties have bypassed the BAS for treatment facilities capable of surgery. We describe the care provided at these treatment facilities during 2007-2020. METHODS This is a secondary analysis of previously described data from the Department of Defense Trauma Registry. We included encounters with the documentation of an assessment or intervention at a BAS or forward operating base from January 1, 2007 to March 17, 2020. We utilized descriptive statistics to characterize these encounters. RESULTS There were 28,950 encounters in our original dataset, of which 3.1% (884) had the documentation of a prehospital visit to a BAS. The BAS cohort was older (25 vs. 24, P < .001) The non-BAS cohort saw a larger portion of pediatric (<18 years) patients (10.7% vs. 5.7%, P < .001). A higher proportion of BAS patients had nonbattle injuries (40% vs. 20.7%, P < .001). The mean injury severity score was higher in the non-BAS cohort (9 vs. 5, P < .001). A higher proportion of the non-BAS cohort had more serious extremity injuries (25.1% vs. 18.4%, P < .001), although the non-BAS cohort had a trend toward serious injuries to the abdomen (P = .051) and thorax (P = .069). There was no difference in survival. CONCLUSIONS The BAS was once a critical point in casualty evacuation and treatment. Within our dataset, the overall number of encounters that involved a stop at a BAS facility was low. For both the asymmetric battlefield and multidomain operations/large-scale combat operations, the current model would benefit from a more robust capability to include storage of blood, ventilators, and monitoring and hold patients for an undetermined amount of time.