STUDIES OF THERMAL INJURY. VI. HYPERPOTASSEMIA CAUSED BY CUTANEOUS EXPOSURE TO EXCESSIVE HEAT1

Abstract

Two groups of pigs were immersed in hot water. One group was exposed at 47[degree] and the other at 75 [degree]C. During continuous immersion at 47 [degree]C, death occurred after exposures ranging between 26-50 mins. Although internal (heart''s blood) temps. as high as 45.5 [degree]C were attained, hemolysis was negligible and the greatest increment observed in plasma K was 5.8 milli-equivalents per liter (meq/L). After immersion at 75 [degree]C, the plasma K rose by as much as 17.2 meq/L and death occurred between 10 and 14 mins. during continuous exposure. An increment in plasma K as high as 14.2 meq/L was observed in an animal whose internal (heart''s blood) temp. did not rise higher than 40.8[degree]C. The excess plasma K in these animals was due principally to hemolysis. Dogs immersed in water at 75 [degree]C failed to show comparable rises in plasma K. 3.8 meq/L was the greatest increment observed. This animal died after 25 mins. during a continuous exposure at 75 [degree]C and showed 31.9% hemolysis at the time of death. A rise in the plasma K of the pig by as much as 4.1 meq/L may occur in a few mins. as a result of severe agonal asphyxia and by as much as 7.5 meq/L in an hr. as a result of postmortem change. Heparinized pigs'' blood was heated in vitro at temps. ranging between 40 and 63 [degree]C. At temps. under 52 [degree]C plasma increases as great as 6.7 meq/L were observed. At temps. below 52 [degree]C the increase was due almost entirely to leakage of K from intact erythrocytes. When the blood was heated at 55 [degree]C and higher, K was released from erythrocytes more rapidly and was derived in part from leakage and in part from hemolysis.