The use of specific thromboxane inhibitors to preserve the dermal microcirculation after burning.

Selective thromboxane inhibitors were evaluated as a pharmacological agent in the prevention of progressive dermal ischemia after burning. Standardized partial-thickness burns were inflicted on guinea pigs. Burned guinea pigs were separated into four groups: one served as a control, one was treated with Imidazole, one with dipyridamole, and the other with methimazole. Histology and depth of dermal perfusion were evaluated by the India ink perfusion technique. Untreated controls showed progressive dermal ischemia with complete absence of India ink-filled vessels in the dermis by 24 hours. Imidazole, dipyridamole, and methimazole improved dermal perfusion as suggested by relative levels of India Ink filling. Preservation of dermal appendages was seen secondarily to improved dermal microcirculation with an eight-fold increase in hair follicles in treated guinea pigs compared with controls. This study suggest that thromboxane plays a role in progressive dermal ischemia. Selective inhibition of thromboxane avoids the side effects associated with complete suppression of the metabolism of arachidonic acid.