Inhibition of Fibrinolysis in the Burned-Infected Rat: Antiplasmin Induced by Burn Wound Infection

Abstract

SummaryInfection is the leading cause of death in the burned patient. To study the effects of uncomplicated and lethally-infected burn wounds on certain hematologic indices, a dorsal scald burn was administered to 250 rats. One group was then infected with Pseudomonas aeruginosa. These rats expired within 10 days. A burned, uninfected, group survived. Sequential determinations were made of fibrinogen, fibrinolysis, antiplasmins, plasminogen antiactivators, cultures, and autopsy findings.Fibrinogen concentrations were higher in the infected animals within 2 days postbum and at day 3 (p <0.05). Plasminogen levels fell precipitously 3 days postburn in the burned-infected group. Acid neutralization of antiplasmins was not entirely effective. Serum from infected animals markedly prolonged the lysis time of clots in a standard test system, lowered plasmin activity in the caseinolytic assay, and transiently prolonged the euglobulin lysis time.The cause of these findings remains unknown. The marked fall in plasminogen in the infected animals may be entirely due to unneutralized antiplasmin activity and was coincident with a decline in fibrin-related antigens. These antiplasmins may exert deleterious effects on microcirculatory dynamics and were closely linked to the animals’ demise.