Combat MEDEVAC: A comparison of care by provider type for en route trauma care in theater and 30-day patient outcomes.

BACKGROUND: Medical evacuation (MEDEVAC) is the movement and en route care of injured and medically compromised patients by medical care providers via helicopter. Military MEDEVAC platforms provide life-saving interventions that improve survival in combat. There is limited evidence to support decision making related to en route care and allocation of resources. The association between provider type and en route care is not well understood. Our objective was to describe MEDEVAC providers and identify associations between provider type, procedures performed, and outcomes.

METHODS: We conducted an IRB approved, retrospective record review of patients traumatically injured in combat, evacuated by MEDEVAC from the point of injury POI, between 2011 and 2014. Data abstracted included injury description, provider type, procedures performed, medications administered, survival, and 30-day outcomes. Subjects were grouped according to provider type: Medics, Paramedics, and ADV (advanced providers to include nurses, physician assistants, and physicians). Groups were compared. Analyses were performed using chi-square tests for categorical variables and ANOVA tests (Kruskal-Wallis tests) for continuous variables. A p-value < 0.05 was considered significant.

RESULTS: MEDEVAC records were reviewed and data were abstracted from 1,237 subjects. The providers were comprised of Medics 76%, Paramedics 21%, and ADV 4%. Patient and injury demographics were similar among groups. ADV were most likely to perform intubation, chest needle decompressions (p<0.0001), and hypothermia prevention (p=0.01). Paramedics were most likely to administer blood en route (p<0.0001). All other procedures were similar between groups. Paramedics were most likely to administer ketamine (p<0.0001), any analgesic (p<0.0001), or any medication en route (p<0.0001). Incidence rates of en route events (pain, hypoxia, abnormal hemodynamics, vital signs) were similar between provider types. In theater and 30-day survival rates were similar between provider types.

CONCLUSION: Providers with higher level training were more likely to perform more advanced procedures during en route care. Our study found no significant association between provider type and in theater or 30-day mortality rates. Upon subgroup analysis, no difference was found in patients with an ISS > 16. More evidence is needed to determine the appropriate level of MEDEVAC personnel training and skill maintenance necessary to minimize combat mortality.

LEVEL OF EVIDENCE: Level III, therapeutic.