Effects of Haemodilution and Rewarming with Regard to Digital Amputation in Frostbite Injury: An Experimental Study in the Rabbit

Abstract

Peripheral vascular failure with haematological and haemodynamic changes occurs after frostbite injuries. In order to study the effects of normovolemic haemodilution on the extent of digital necrosis, the paws of rabbits were haemodiluted and frozen to -15 degrees C. Dextran or gelatin was used as the plasma substitute in two groups and the rewarming after the cold injury was performed either at room temperature (22 degrees C) or with hot water baths (38 degrees C). The extent of necrosis was significantly less in the rabbits haemodiluted with dextran or gelatin and rewarmed in hot water baths.

Frostbite treatment: a systematic review with meta-analyses

“…The limited number of reports on these treatments precluded us from drawing conclusions about their clinical effectiveness. Low molecular weight dextran, thought to reduce blood viscosity and inhibit thrombus formation, has demonstrated decreased necrosis in animal models of frostbite [ 13 , 43 , 44 ], but is not available in many countries. Nonsteroidal anti-inflammatory drugs (NSAIDs) block the effects of cyclo-oxygenases, decreasing the production of prostaglandins and thromboxane, mediators that can cause increased vasoconstriction, ischemia, and inflammatory tissue damage [ 3 , 45 ].…”

Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Frostbite: 2019 Update

“…Intravenous low molecular weight dextran (LMWD) decreases blood viscosity by preventing red blood cell aggregation and formation of microthrombi and can be given in the field once it has been warmed. In some animal studies, the extent of tissue necrosis was found to be significantly less than in control subjects when LMWD was used 24 –27 and was more beneficial if given early. 28 In one animal trial, 28 tissue in the LMWD group thawed slightly more rapidly, but overall tissue loss was no different from that of control animals.…”

Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Frostbite: 2024 Update

“…Intravenous low molecular weight dextran (LMWD) decreases blood viscosity by preventing red blood cell aggregation and formation of microthrombi and can be given in the field once it has been warmed. In some animal studies, the extent of tissue necrosis was found to be significantly less than in control subjects when LMWD was used [26][27][28][29] and was more beneficial if given early. 30 In one animal trial, 30 tissue in the LMWD group thawed slightly more rapidly, but overall tissue loss was no different from that of control animals.…”