Thermodynamic and logistic considerations for treatment of hypothermia.

Hypothermia increases mortality rates and should be treated aggressively in the forward echelons of care, but no practical solution exists to accomplish such treatment. The enormous energy burden for this task requires maximal thermodynamic efficiency for a practical portable solution. This review article presents an overview of the clinical and thermodynamic challenges related to the development of a successful system for treatment of hypothermia in the forward echelons. Specific issues addressed include (1) the clinical and logistical reasons why thermal resuscitation should be attempted at all in such a difficult environment, (2) the thermodynamic reasons why warm intravenous fluids, although helpful in not worsening hypothermia, cannot safely transmit enough energy to treat established hypothermia, (3) which among the various methods of rewarming are most likely to result in successful therapy, and (4) the energetic considerations that dictate that any practical portable solution to the treatment of hypothermia must use hydrocarbon combustion as the source of heat.