Coagulopathy related to dilution and hypotension during massive transfusion

A retrospective review of 64 patients receiving more than 10 units of red cell concentrate plus crystalloid within 12 h revealed two consecutive patterns of elevation of the partial thromboplastin time (PTT). The PTT at 3 to 4 h (PTT3–4) correlated with the number of liters of crystalloid (LC) infused over the first 3 h (PTT3–4 = 37 + 7 LC, r = .7643, p < .001); the PTT thereafter (PTT4+) correlated with the number of hours of closely antecedent hypotension (AH) (PTT4+ = 37 + 21 AH, r = .8680, p < .001). These data indicate a transient dilutional coagulopathy, followed by coagulopathy related to the duration of closely AH. Whether this latter is due to impaired production, disseminated intravas-cular coagulation, or dilution due to internal shifts of fluids and/or proteins, remains to be clarified. Therapeutic implications of these data are discussed.