Ice water submersion for rapid cooling in severe drug-induced hyperthermia

Context. The optimal method of cooling hyperthermic patients is controversial. Although controlled data support ice water submersion, many authorities recommend a mist and fan technique. We report two patients with drug-induced hyperthermia, to demonstrate the rapid cooling rates of ice water submersion. Case details. Case 1. A 27-year-old man presented with a sympathomimetic toxic syndrome and a core temperature of 41.4 degrees C after ingesting 4-fluoroamphetamine. He was submerged in ice water and his core temperature fell to 38 degrees C within 18 minutes (a mean cooling rate of 0.18 degrees C/min). His vital signs stabilized, his mental status improved and he left on hospital day 2. Case 2. A 32-year-old man with a sympathomimetic toxic syndrome after cocaine use was transported in a body bag and arrived with a core temperature of 44.4 degrees C. He was intubated, sedated with IV benzodiazepines, and submerged in ice water. After 20 mins his temperature fell to 38.8 degrees C (a cooling rate of 0.28 degrees C/min). He was extubated the following day, and discharged on day 10. Discussion. In these two cases, cooling rates exceeded those reported for mist and fan technique. Since the priority in hyperthermia is rapid cooling, clinical data need to be collected to reaffirm the optimal approach.