Admission hypo- or hyperthermia and survival after trauma in civilian and military environments

BACKGROUND: In the care of patients with traumatic injuries, focus is placed on hypothermia secondary to its deleterious impact on the coagulation cascade. However, there is scant information on the mortality effect of hyperthermia. STUDY OBJECTIVES: We hypothesized that both hypothermia and hyperthermia are associated with decreased survival in patients with traumatic injuries. Furthermore, we hypothesized that in the military setting, the incidence of hyperthermia would be greater compared to the civilian environment and thus contributing to an increase in mortality. METHODS: Registries compared were the National Trauma Data Bank (NTDB), three civilian Level I trauma centers, and military combat support hospitals. The NTDB was used as a reference to define hypothermia and hyperthermia based upon survival. Admission temperature and outcome were known for 4,093 civilian and 4,394 military records. RESULTS: Hypothermia was defined as < 36°C and hyperthermia > 38°C as mortality increased outside this range. The overall mortality rates were 3.5% for civilians and 2.5% for military (p < 0.05). Of civilians, 9.3% (382) were hypothermic and 2.2% (92) hyperthermic. The incidence of hypothermia in the military patients was 6.0% (263) and for hyperthermia the incidence was 7.4% (327). Irrespective of group, patients with hypothermia or hyperthermia had an increased mortality compared to those with normal temperatures, ([for civilian:military ] hypothermia 12%:11%; normal 2%:2%; hyperthermia 14%:4%). CONCLUSION: Care of the victim with traumatic injuries emphasizes avoidance of hypothermia; however, hyperthermia is also detrimental. The presence of hypothermia or hyperthermia should be considered in the initial treatment of the patient with traumatic injuries.