Massive Transfusion and Coagulopathy

Abstract

Massive Transfusion and Coagulopathy ) ( Transfusion Alternatives in Transfusion MedicineMost studies of MT have been conducted in trauma patients and are, for obvious reasons, primarily retrospective or uncontrolled observational studies.9 Given the variable and complex clinical context, the results of these studies have seldom led to definitive conclusions. Furthermore, factors other than the transfusion strategy, related to the trauma itself, may have led to the observed hemostatic abnormalities.10 Unfortunately, conventional teaching has sometimes failed to appreciate the evolution of transfusion practices and the context in which these practices were developed. As a result, anesthesiologists may have been led to inappropriately apply transfusion strategies, e.g., those specifically developed for trauma patients at a time when MWB was available, to a patient receiving red cell concentrates for massive bleeding during elective surgery. The situation can become even more confusing when disseminated intravascular coagulation (DIC) is associated with trauma and/or MT.In this article on MT and coagulopathy, we will attempt to do the following:1. Identify the causes of coagulopathy in massively transfused adult and previously hemostatically competent patients in order to determine the most appropriate transfusion/treatment strategies.2. Differentiate between the elective surgical setting and trauma, hypothesizing that recommendations derived from studies of MT in trauma patients may not apply to elective surgical patients.We searched MEDLINE for published articles on massive transfusion, using the search terms "transfusion," "trauma," "surgery," "coagulopathy," and "hemostatic defects." Articles dealing with obstetrical and pediatric patient populations were not retained, nor were those dealing with specific hemostatic anomalies such as cardiopulmonary bypass (CPB), liver transplantation and pre-existing coagulation disorders. A preliminary version of the text was circulated to experts from the (Perioperative Hemostasis Interest Group) for comments and suggestions. A narrative format was adopted given that the heterogeneity of the published studies was too great and not conducive to a more formal review. Since the nature of blood products available to clinicians has changed over time, the retrieved articles were organized and reviewed by date of publication in order to better understand the evolution of our knowledge of MT and coagulopathy. Variables Responsible for Coagulopathy in Association With Massive Transfusion Platelets HemodilutionSince the publication of Miller' s classic study on coagulation defects associated with massive blood transfusions, thrombocytopenia resulting from hemodilution has been thought to be the most important hemostatic abnormality associated with MT.11 This explanation is intuitively appealing: replacement of lost blood with fluids that do not contain platelets (or coagulation factors) results in a dilutional coagulopathy. However appealing the notion, hemodilution fails to explain s...

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Management of Hemorrhage During Gynecologic Surgery

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