Out-of-hospital surface cooling to induce mild hypothermia in human cardiac arrest: a feasibility trial.

AIM

The earliest initiation of mild hypothermia after resuscitation from cardiac arrest is crucial. This study aimed to evaluate the feasibility and safety of out-of-hospital surface cooling in such cases.

METHODS

Cooling pads stored below 0 degrees C in the ambulance were applied as soon as possible after restoration of spontaneous circulation in the out-of-hospital setting. This continued in the emergency department until an oesophageal temperature of 34 degrees C was reached, when the pads were removed. A target temperature of 33 degrees C was maintained for 24 h. Results are given as median and interquartile range.

RESULTS

From September 2006 to January 2007, 15 victims of cardiac arrest were included. Cooling was initiated at 12 (8.5-15) min after restoration of spontaneous circulation. Oesophageal temperatures decreased from 36.6 (36.2-36.6) degrees C to 33 degrees C within 70 (55-106) min. Hospital admission was at 45 (34-52) min, with oesophageal temperatures of 35.4 (34.6-35.9) degrees C; the target 33 degrees C was achieved 50 (29-82) min after admission. No skin lesions were observed.

CONCLUSION

Non-invasive surface cooling immediately after resuscitation from cardiac arrest, in the out-of-hospital setting, proved to be feasible, fast and safe. Whether early cooling will improve neurological outcome needs to be determined in future studies.