Plasma: Everything Old is New Again: New Formulations and Applications of a Long-Trusted Transfusion Product

Plasma products have been used for decades to restore vascular volume, deliver needed blood proteins and provide oncotic support. Traditionally plasma has been utilized in the form of fresh frozen plasma (FFP). Most commonly this is manufactured by removing the cellular component of whole blood and retaining the liquid portion. This plasma is then frozen and can be stored frozen for up to one year. However, this relatively short shelf life, the need to maintain the product frozen and time needed to thaw the product before use (especially in emergent settings) make it cumbersome in some situations.

Several products are becoming available to address the limitations of FFP. Liquid plasma is plasma which has never been frozen and can be refrigerated in dogs for up to 35 days. This product has been shown to be similar to FFP in terms of coagulation proteins and can be rapidly prepared for administration without the need to thaw the product. Freeze dried plasma (FDP) has been developed in multiple species as a shelf stable resuscitation product. In both dogs and humans, it has been shown to be similar to FFP in terms of coagulation activity and biochemical profile.  Low volume, hypotensive hemostatic resuscitation is a strategy in which blood products are administered in order to increase mean arterial blood pressure enough to restore perfusion of critical organs. This approach has been recommended in both humans and dogs for the treatment of severe hemorrhagic shock until definitive control of hemorrhage is achieved. Benefits of plasma as a component of resuscitation in hemorrhagic shock include preservation of the endothelial glycocalyx barrier, replacement of fibrinogen, clotting factors and albumin as well as effective circulating volume replacement without hemodilution of coagulation factors.

Freeze dried plasma is created by obtaining individual or pooled liquid plasma and lyophilizing the plasma to obtain a sterile, dehydrated, shelf stable product. The resultant product is shelf stable for years and can be rapidly reconstituted with sterile water. The nature of FDP allows for a novel product to be employed – a concentrated, hyperosmotic form of plasma providing the same quantity of plasma proteins at a lower volume. This concentrated product has the potential to allow for faster infusion time at a lower volume than traditional plasma, producing benefits in emergent scenarios such as more rapid hemostatic resuscitation of acutely traumatized dogs.