Damage Control Resuscitation.

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.

Optimizing Transfusion Ratios in Massive Transfusion Protocols: An Argument Against the 1:1:1 Dogma and Approach to Trauma Resuscitation.

We believe that the current practice of transfusing red blood cells (RBCs), plasma, and platelets in a 1:1:1 ratio is not optimal in massive transfusion protocols (MTPs) and is based on a simple yet profound misconception regarding the preparation of component blood products. This 1:1:1 approach ignores the additional fluids added for anticoagulation and preservation of the components and assumes that there is a one-size-fits-all ratio that must be used across all types of trauma. In this article, we explain the rationale behind our conclusion with supporting figures and suggest that although the 1:1:1 ratio might be within the range of hemostasis, it falls near the lower cusp of hemostasis, making it less than ideal. The patient in mind was one in whom transfusion was expected to exceed 10 units of packed RBCs (pRBCs) in a combat environment where the situation was too hectic for additional testing. The goal was to keep the patient within a hemostatic range until the crisis phase was averted and the transition could then be made to goal-directed therapy with point-of-care testing.

Anti-c (Little c) IgM: An Uncommonly Observed but Expected Phenomenon.

The c-antigen (little c) is part of the Rh blood group system and is found in approximately 80% of the United States population. Anti-c antibody develops in individuals sensitized through previous exposure and is associated with acute and delayed hemolytic transfusion reactions as well as hemolytic disease of the newborn (HDN). Most antibodies produced against Rh antigens are of the immunoglobulin (Ig) G type. We present a case of anti-c in a 30-year-old white woman who was gravida 2 para 1 (G2P1), whose laboratory workup at the time of admission for delivery suggests recent exposure and seroconversion in the latter part of her pregnancy, with evidence of the expected but rarely demonstrated presence of anti-c IgM and IgG.

Low titer group O whole blood in emergency situations.

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.

The ratio of fibrinogen to red cells transfused affects survival in casualties receiving massive transfusions at an army combat support hospital.

BACKGROUND: To treat the coagulopathy of trauma, some have suggested early and aggressive use of cryoprecipitate as a source of fibrinogen. Our objective was to determine whether increased ratios of fibrinogen to red blood cells (RBCs) decreased mortality in combat casualties requiring massive transfusion. METHODS: We performed a retrospective chart review of 252 patients at a U.S. Army combat support hospital who received a massive transfusion (>or=10 units of RBCs in 24 hours). The typical amount of fibrinogen within each blood product was used to calculate the fibrinogen-to-RBC (F:R) ratio transfused for each patient. Two groups of patients who received either a low (<0.2 g fibrinogen/RBC Unit) or high (>or=0.2 g fibrinogen/RBC Unit) F:R ratio were identified. Mortality rates and the cause of death were compared between these groups, and logistic regression was used to determine if the F:R ratio was independently associated with survival. RESULTS: Two-hundred and fifty-two patients who received a massive transfusion with a mean (SD) ISS of 21 (+/-10) and an overall mortality of 75 of 252 (30%) were included. The mean (SD) F:R ratios transfused for the low and high groups were 0.1 grams/Unit (+/-0.06), and 0.48 grams/Unit (+/-0.2), respectively (p < 0.001). Mortality was 27 of 52 (52%) and 48 of 200 (24%) in the low and high F:R ratio groups respectively (p < 0.001). Additional variables associated with survival were admission temperature, systolic blood pressure, hemoglobin, International Normalized Ratio (INR), base deficit, platelet concentration and Combined Injury Severity Score (ISS). Upon logistic regression, the F:R ratio was independently associated with mortality (odds ratio 0.37, 95% confidence interval 0.171-0.812, p = 0.013). The incidence of death from hemorrhage was higher in the low F:R group, 23/27 (85%), compared to the high F:R group, 21/48 (44%) (p < 0.001). CONCLUSIONS: In patients with combat-related trauma requiring massive transfusion, the transfusion of an increased fibrinogen: RBC ratio was independently associated with improved survival to hospital discharge, primarily by decreasing death from hemorrhage. Prospective studies are needed to evaluate the best source of fibrinogen and the optimal empiric ratio of fibrinogen to RBCs in patients requiring massive transfusion.