Early Resuscitation of Patients With Non-exsanguinating Trauma Using Packed Red Blood Cells Versus Low-Volume Crystalloids: Have We Gone Too Far?

The early resuscitation of patients with mild to moderate non-exsanguinating trauma has shifted from the conventional use of one to two liters of crystalloids to the use of one to two units of PRBC. This evolution assumes that the transfusion of PRBC is superior to the administration of any volume of crystalloids because of the propensity of crystalloids to migrate from the intravascular to the interstitial space leading to organ dysfunction, organ failure, and worse outcomes. However, the premise of the fluid migration relies on Starling original model of fluid exchange between the hydrostatic and oncotic pressure without considering whether the endothelial surface glycocalyx (ESG) is affected by the degree of traumatic insult and by the duration and depth of hypotension. It fails to account for the changes that occur to the PRBC during storage from the standpoint of off-loading of oxygen and the ability to negotiate the microcirculation. This review explores the impact of the burden of trauma and hemorrhage on the ESG, the changes to the RBCs that occur during storage, particularly their diminished capacity to offload oxygen and to negotiate low-shear microvascular districts, leading to failure to improve oxygen consumption despite the increase in oxygen delivery. We argue that the recent trend toward early resuscitation with one to two units of PRBC rather that low-volume crystalloids, in patients with non-exsanguinating mild to moderate trauma lacks sufficient justification.