Surviving in a crevasse

We read with interest the case report by Peter Paal and colleagues (Feb 9, p 506)1 of a 70-year-old man surviving 6 days in a crevasse after a fall while crossing a glacier alone. Unlike the Case Report of successful resuscitation from 13·7°C,2 this climber's core temperature was 33·5°C. The authors speculate that the rescue foil used by the individual might have been a key factor in maintaining body temperature. We concur that heat loss occurs by different mechanisms,3 and that airtight foil will reduce convective and evaporative heat losses from the skin—the most important physical routes of heat loss in a cold environment.