Whole blood is the preferred product for resuscitation of severe traumatic hemorrhage. It contains all the elements of blood that are necessary for oxygen delivery and hemostasis, in nearly physiologic ratios and concentrations. Group O whole blood that contains low titers of anti-A and anti-B antibodies (low titer group O whole blood) can be safely transfused as a universal blood product to patients of unknown blood group, facilitating rapid treatment of exsanguinating patients. Whole blood can be stored under refrigeration for up to 35 days, during which it retains acceptable hemostatic function, though supplementation with specific blood components, coagulation factors or other adjuncts may be necessary in some patients. Fresh whole blood can be collected from pre-screened donors in a walking blood bank to provide effective resuscitation when fully tested stored whole blood or blood components are unavailable and the need for transfusion is urgent. Available clinical data suggest that whole blood is at least equivalent if not superior to component therapy in the resuscitation of life-threatening hemorrhage. Low titer group O whole blood can be considered the standard of care in resuscitation of major hemorrhage.

The early transfusion of plasma is important to ensure optimal survival of patients with traumatic hemorrhage. In military and remote or austere civilian settings, it may be impossible to move patients to hospital facilities within the first few hours of injury. A dried plasma product with reduced logistical requirements is needed to enable plasma transfusion where medically needed, instead of only where freezers and other equipment are available. First developed in the 1930s, pooled lyophilized plasma was widely used by British and American forces in WWII and the Korean War. Historical dried plasma products solved the logistical problem but were abandoned because of disease transmission. Modern methods to improve blood safety have made it possible to produce safe and effective dried plasma. Dried plasma products are available in France, Germany, South Africa, and a limited number of other countries. However, no product is available in the US. Promising products are in development that employ different methods of drying, pathogen reduction, pooling, packaging, and other approaches. Although challenges exist, the in vitro and in vivo data suggest that these products have great potential to be safe and effective. The history, state of the science, and recent developments in dried plasma are reviewed.

In past and ongoing military conflicts, the use of whole blood (WB) as a resuscitative product to treat trauma-induced shock and coagulopathy has been widely accepted as an alternative when availability of a balanced component-based transfusion strategy is restricted or lacking. In previous military conflicts, ABO group O blood from donors with low titers of anti-A/B blood group antibodies was favored. Now, several policies demand the exclusive use of ABO group-specific WB. In this short review, we argue that the overall risks, dangers, and consequences of "the ABO group-specific approach," in emergencies, make the use of universal group O WB from donors with low titers of anti-A/B safer. Generally, risks with ABO group-specific transfusions are associated with in vivo destruction of the red blood cells transfused. The risk with group O WB is from the plasma transfused to ABO-incompatible patients. In the civilian setting, the risk of clinical hemolytic transfusion reactions (HTRs) due to ABO group-specific red blood cell transfusions is relatively low (approximately 1:80,000), but the consequences are frequently severe. Civilian risk of HTRs due to plasma incompatible transfusions, using titered donors, is approximately 1:120,000 but usually of mild to moderate severity. Emergency settings are often chaotic and resource limited, factors well known to increase the potential for human errors. Using ABO group-specific WB in emergencies may delay treatment because of needed ABO typing, increase the risk of clinical HTRs, and increase the severity of these reactions as well as increase the danger of underresuscitation due to lack of some ABO groups. When the clinical decision has been made to transfuse WB in patients with life-threatening hemorrhagic shock, we recommend the use of group O WB from donors with low anti-A/B titers when logistical constraints preclude the rapid availability of ABO group-specific WB and reliable group matching between donor and recipient is not feasible.

Damage control resuscitation (DCR) is a strategy for resuscitating patients from hemorrhagic shock to rapidly restore homeostasis. Efforts are focused on blood product transfusion with whole blood or component therapy closely approximating whole blood, limited use of crystalloid to avoid dilutional coagulopathy, hypotensive resuscitation until bleeding control is achieved, empiric use of tranexamic acid, prevention of acidosis and hypothermia, and rapid definitive surgical control of bleeding. Patients receiving uncrossmatched Type O blood in the emergency department and later receiving cumulative transfusions of 10 or more red blood cell units in the initial 24-hour post-injury (massive transfusion) are widely recognized as being at increased risk of morbidity and mortality due to exsanguination. Ideally, these patients should be rapidly identified, however anticipating transfusion needs is challenging. Useful indicators of massive transfusion reviewed in this guideline include: systolic blood pressure <110 mmHg, heart rate > 105 bpm, hematocrit <32%, pH < 7.25, injury pattern (above-the-knee traumatic amputation especially if pelvic injury is present, multi-amputation, clinically obvious penetrating injury to chest or abdomen), >2 regions positive on Focused Assessment with Sonography for Trauma (FAST) scan, lactate concentration on admission >2.5, admission international normalized ratio ≥1.2-1.4, near infrared spectroscopy-derived StO2 < 75% (in practice, rarely available), BD > 6 meq/L. Unique aspects of out-of-hospital DCR (point of injury, en-route, and remote DCR) and in-hospital (Medical Treatment Facilities: Role 2b/Forward surgical teams - role 3/ combat support hospitals) are reviewed in this guideline, along with pediatric considerations.

Therapeutic, level IV.