Induction of prehospital therapeutic hypothermia after resuscitation from nonventricular fibrillation cardiac arrest*

Abstract

To evaluate the effects on temperature and outcome at hospital discharge of a pre-hospital rapid infusion of large volume, ice-cold intravenous Hartmann's solution in patients with out-of-hospital cardiac arrest and an initial cardiac rhythm of asystole or pulseless electrical activity. Prospective, randomized, controlled clinical trial. Pre-hospital emergency medical service and 12 critical care units in Melbourne, Australia. One hundred and sixty three patients who had been resuscitated from cardiac arrest with an initial cardiac rhythm of asystole or pulseless electrical activity. Patients were randomized to either pre-hospital cooling using a rapid infusion of up to two litres ice-cold Hartmann's solution (82 patients) or cooling after hospital admission (81 patients). The planned duration of therapeutic hypothermia (32°C–34°C) in both groups was 24 hrs. Patients allocated to pre-hospital cooling received a median of 1500 ml of ice-cold fluid. This resulted in a mean decrease in core temperature of 1.4°C compared with 0.2°C in hospital cooled patients (p Conclusions: In adults who have been resuscitated from out-of-hospital cardiac arrest with an initial cardiac rhythm of asystole or pulseless electrical activity, pre-hospital cooling using a rapid infusion of large-volume, ice cold intravenous Hartmann's solution decreases core temperature at hospital arrival and decreases the time to therapeutic hypothermia. In patients with a cardiac cause of the arrest, this treatment may increase the rate of favorable outcome at hospital discharge. Further larger studies should evaluate the effects of pre-hospital cooling when the initial cardiac rhythm is asystole or pulseless electrical activity, particularly in patients with a cardiac cause of the arrest.