A retrospective analysis of air-evacuated hypothermia patients

This study reviews the outcome of 17 hypothermic patients air evacuated by a civilian helicopter transport service. Age (33 +/- 23), type and duration of exposure, and rewarm methods were examined for each patient. Temperature (T), heart rate (HR), blood pressure (BP), respiratory rate (RR), Glasgow coma score (GCS), trauma score (TS), CRAMS score (CS), and cardiac rhythm in the pre-hospital setting and in the emergency department (ED) were compared to outcome. Eight of the patients had extensive exposure to a cold environment ranging from 4 h to 10 d. The remaining 9 patients were exposed to cold water ranging from 15 min to 4.5 h. By severity of hypothermia as measured in the ED, 6 patients who were hypothermic at the scene were normothermic (t greater than 35 degrees C), 5 patients were classified as mild (t = 35-31.5 degrees C), 3 as moderate (T less than 31.5-25.5 degrees C), and 3 patients were severely hypothermic (T less than 25.5 degrees C). The GCS, TS, and CS were not indicative of outcome. During rewarming, 3 patients had paradoxical temperature drops, and 5 patients had atrial fibrillation. Three patients required cardiopulmonary resuscitation in the field. Two were discharged with resolving disabilities, and 1 expired. No ventricular fibrillation or J waves occurred. All patients were effectively rewarmed without incident. All patient disabilities and the single fatality were not directly related to hypothermia. There were no long-term adverse consequences of helicopter transport in these hypothermic patients.