Prehospital cooling with hypothermia caps (PreCoCa): a feasibility study.

BACKGROUND: Animal studies suggest that the induction of therapeutic hypothermia in patients after cardiac arrest should be initiated as soon as possible after ROSC to achieve optimal neuroprotective benefit. A "gold standard" for the method of inducing hypothermia quickly and safely has not yet been established. In order to evaluate the feasibility of a hypothermia cap we conducted a study for the prehospital setting.

METHODS AND RESULTS: The hypothermia cap was applied to 20 patients after out-of-hospital cardiac arrest with a median of 10 min after ROSC (25/75 IQR 8-15 min). The median time interval between initiation of cooling and hospital admission was 28 min (19-40 min). The median tympanic temperature before application of the hypothermia cap was 35.5 degrees C (34.8-36.3). Until hospital admission we observed a drop of tympanic temperature to a median of 34.4 degrees C (33.6-35.4). This difference was statistically significant (P < 0.001). We could not observe any side effects related to the hypothermia cap. 25 patients who had not received prehospital cooling procedures served as a control group. Temperature at hospital admission was 35.9 degrees C (35.3-36.4). This was statistically significant different compared to patients treated with the hypothermia cap (P < 0.001).

CONCLUSIONS: In summary we demonstrated that the prehospital use of hypothermia caps is a safe and effective procedure to start therapeutic hypothermia after cardiac arrest. This approach is rapidly available, inexpensive, non-invasive, easy to learn and applicable in almost any situation.