Induction of therapeutic hypothermia during prehospital CPR using ice-cold intravenous fluid

Primarily, to investigate induction of therapeutic hypothermia during prehospital cardiopulmonary resuscitation (CPR) using ice-cold intravenous fluids. Effects on return of spontaneous circulation (ROSC), rate of rearrest, temperature and haemodynamics were assessed. Additionally, the outcome was followed until discharge from hospital.

Seventeen adult prehospital patients without obvious external causes for cardiac arrest were included. During CPR and after ROSC, paramedics infused +4 degrees C Ringer's acetate aiming at a target temperature of 33 degrees C.

ROSC was achieved in 13 patients, 11 of whom were admitted to hospital. Their mean initial nasopharyngeal temperature was 35.17+/-0.57 degrees C (95% CI), and their temperature on hospital admission was 33.83+/-0.77 degrees C (-1.34 degrees C, p<0.001). The mean infused volume of cold fluid was 1571+/-517 ml. The rate of rearrest after ROSC was not increased compared to previous reports. Hypotension was observed in five patients. Of the 17 patients, 1 survived to hospital discharge.

Induction of therapeutic hypothermia during prehospital CPR and after ROSC using ice-cold Ringer's solution effectively decreased nasopharyngeal temperature. The treatment was easily carried out and well tolerated.