Hypothermia may be seen both as a presenting problem and as a part of
therapeutic strategy. An illustrative case is presented. In our case o
f severe head trauma, hypothermia was used as a therapeutic modality t
o minimize the brain injury. While hypothermic, the patient developed
severe hypokalemia and was supplemented with 400 mEq of potassium. Upo
n rewarming, severe hyperkalemia occurred with resultant fatal arrhyth
mias. Severe hypokalemia may be seen in hypothermic patients, which re
presents a shift of potassium rather than a true loss. Careful managem
ent of this electrolyte problem must be given to avoid hyperkalemia wi
th rewarming.