1. Plasma concentrations of glucose, lactate, amino acids, non-esterified fatty acids, glycerol, ketone bodies, insulin and cortisol were measured in 43 elderly patients with hypothermia. In 15 of these patients forearm arteriovenous differences were also measured. Core temperatures ranged from 25.9 to 35.5 degrees C. 2. The metabolic state was of mobilization of glycogen and triacylglycerol stores, with high plasma concentrations of lactate and lipid metabolites. The plasma concentration of ...