Plasma transfusion

Abstract

Resuscitation of the injured patient continues to be a highly debated and rapidly evolving topic. Multiple studies have struggled to determine the optimal strategy to combat, and ultimately prevent, trauma-induced coagulopathy. This chapter discusses the risks and benefits of resuscitation protocols utilizing plasma in its various forms. Plasma is the aqueous portion of blood that contains coagulation factors, fibrinolytic proteins, albumin, immunoglobulins, and numerous other proteins. Plasma can be obtained via whole blood from phlebotomy or by apheresis. Once collected, it can be frozen for storage. If frozen within 8 hours, the product is labeled as fresh frozen plasma. If frozen after this window but within 24 hours, it is labeled as plasma frozen within 24 hours, or FP24. When these frozen forms are mobilized from the blood bank, they are thawed in a water bath to create thawed plasma, which can be stored in liquid form for up to 5 days prior to transfusion. Liquid plasma is a distinct product derived from whole blood and never frozen. While most centers employ its use for 21-26 days, it can be stored for up to 30 days prior to transfusion. Dried plasma is produced from frozen plasma by lyophilization or spray-drying and then later reconstituted for transfusion. These forms vary in their activity of coagulation factors, but all may be useful in the resuscitation of the injured patient. Beyond the well-known coagulation factors, other proteins and microparticles abound in plasma, and these have profound protective effects. Studies looking at the endotheliopathy associated with hemorrhagic shock have shown a decrease in the inflammatory response, promotion of endothelial repair, and decreased edema with plasma transfusion. Plasma also remains one of the best volume expanders and acid-base buffers available. Protocols utilizing plasma early in resuscitation, at the time of patient presentation, have shown a decrease in the amount of blood products transfused, as well as an improvement in survival. Transfusion ratios of plasma-platelet-red blood cell units in a 1:1:1 ratio show significant improvement reduction in hemorrhage-related mortality compared to 1:1:2. Adverse events are more common with plasma transfusion than with other fractionated blood products, but the overall incidence remains extremely low. Major risks include transfusion-related acute lung injury (TRALI), transfusion-associated circulatory overload (TACO), infectious disease transmission, acute transfusion reactions, and leukocyte-associated reactions. Future possibilities for the development of plasma products have recently focused on dried plasma. French, German, and South African dried plasma products are currently used in their respective countries, but none is approved for use in the United States. With encouraging reports out of recent military and civilian prehospital use and numerous ongoing trials in the United States, dried plasma may be the solution to the many logistical problems inherent in frozen, thawed, and liquid plasma.