CAERvest® - A Novel Endothermic Hypothermic Device for Core Body Cooling. Safety and Efficacy Testing.

Cooling the whole body to 32-34 degrees Centigrade from the normal of around 37 degrees Centigrade for 24 hours has been shown to be an effective way of reducing damage to brain function after return of spontaneous circulation when someone has been resuscitated from cardiac arrest. Cardiac arrest is a form of heart attack where the heart stops pumping. The device is a prototype cooling vest. The investigators anticipate that this will be useful in ambulances, helicopters and emergency departments where there is a need for a portable, safe, easy-to-use, inexpensive, external, effective, readily-controlled and single-patient use device able to reduce body temperature by at least 1 degree Centigrade an hour to initiate cooling. What the investigators are doing in these trials is to demonstrate that the investigators can cool people and to get the best design possible for patient use. That means some of the initial prototypes will not resemble what we expect the eventual device to look like. The investigators will be undertaking the initial trials on 30 normal volunteers.