Plasma and cardiac lactic dehydrogenase activity in burn shock.

Abstract

SummaryAnesthetized dogs subjected to a standardized cutaneous burn injury covering 35% of their surface area showed a marked increase in total plasma LDH activity. The increase in LDH activity was accompanied, as determined in another group of burned dogs, by a significant decrease in cardiac output and an increase in total peripheral resistance and hematocrit. In control dogs, plasma LDH activity showed little or no change during a 4-hr period, while burned dogs increased their plasma LDH activity from 44.7 to 137.0 units/ml. The negative myocardial uptake of LDH indicated that cardiac muscle in burned dogs released LDH into the circulation. In the absence of burn trauma, dogs subjected to the same experimental procedures had no significant efflux of LDH from the heart. The release of myocardial LDH in the burned animal may possibly be related to the action of a burn toxin, a state of myocardial anoxia or the presence of an underlying injury to the heart.