THE IMPACT OF HYPOTHERMIA ON DILUTIONAL COAGULOPATHY

The control of hemorrhage in hypothermic patients with platelet and cl otting factor depletion is often impossible. Determining the cause of coagulopathic bleeding (CB) will enable physicians to appropriately fo cus on rewarming, clotting factor repletion, or both. Objective: To de termine the contribution of hypothermia in producing CB and ascertain if simultaneous hypothermia and dilutional coagulopathy (DC) interact synergistically. Method: Prothrombin time, partial thromboplastin time , and platelet function were determined at assay temperatures of 29-de grees to 37-degrees-C on normal and critically ill, noncoagulopathic ( NC) individuals. Dilutional coagulopathy was created using buffered sa line and the assays repeated. Results: Hypothermic assay at less-than- or-equal-to 35-degrees-C significantly prolonged coagulation times. Th e effect of hypothermia on NC and DC samples was not different. Conclu sion: Assays performed at 37-degrees-C underestimate coagulopathy in h ypothermic patients. The effect of hypothermia on NC and DC is not dif ferent, indicating the lack of a synergistic effect. Normalization of clotting requires both rewarming and clotting factor repletion.