Extra corporeal circulation is used for profoundly hypothermic patients. Rapid core rewarming is possible with this method. However it is a complex procedure that can be accomplished only in intensive care facilities. The risk of complications demands that it is used only when absolutely necessary. The facilities for this method are found only in major medical centers.
Peritoneal lavage is a less complicated procedure and can be used for treating severe hypothermia.
Rapid rewarming is also characteristic of this method. Hayward's 1984 study recorded cardiac temperature. In that investigation, there was conclusive evidence that there was no afterdrop associated with the inhalation rewarming method, nor with spontaneous rewarming, but the rewarming rate of the core, especially the heart, was greatest with the inhalation rewarming technique. The rate of rewarming was greatest for the hot water bath therapy however, afterdrop of the heart temperature was observed. The general awareness of hypothermia is growing.