Induced hypothermia in comatose patients resuscitated from cardiac arrest improves survival and neurological outcome when the initial rhythm is ventricular fibrillation. Results from 26 patients treated with early prehospital cooling, continued in hospital with cold fluids and body surface cooling, are presented. Sixteen patients had no or only minor neurological defects at discharge. Thirteen of 17 patients treated for ventricular fibrillation had a good cerebral outcome at discharge. Two patients had minor complications resulting from the treatment.