The leading cause of death in traumatic injury for both civilian and combat populations worldwide is hemorrhage,1-4 with the majority of deaths occurring in the first 24 hours.5 Stopping hemorrhage with early and balanced resuscitation supports survival for injured patients.6-8 The wide use of whole blood occurred successfully during World War II and remained the preferred resuscitation measure until the 1970s, when blood component therapy began to address the issue of access by providing longer storage times.9,10Several studies have demonstrated a benefit of reduced mortality with the administration of a 1:1:1 ratio of fresh frozen plasma, platelets, and red blood cells (RBCs).11-13 This benefit renewed interest in the use of whole blood in the combat setting. Additional research has shown that cold-stored, low-titer anti-A and anti-B type O whole blood (LTOWB) is being used more often as a universal blood product and is considered safe.14-16 The Joint Trauma System, the Defense Committee on Trauma, and the Armed Services Blood Program provided a consensus statement endorsing whole blood to be used to treat hemorrhagic shock and LTOWB as the resuscitation product of choice.17 This utilization and combat research on whole blood has led to interest in its use in civilians with traumatic injury.The purpose of this clinical evidence review is to examine studies comparing the effects of using whole blood versus blood component therapy on total transfusion volumes and mortality outcomes in the civilian trauma population.The strategy included searching PubMed and Embase with the search terms wounds and injuries [Majr] AND blood transfusion [Majr] AND whole (PubMed) and injury/exp/mj AND blood transfusion/exp/mj AND whole (EMBASE). The search was limited to evidence from the past 10 years. Studies included traumatically injured patients in the civilian prehospital or hospital setting who received whole blood or whole blood with blood component therapy compared with blood component therapy alone. Studies excluded consisted of combat casualty settings, pediatric populations (<15 years old), or ambulatory blood banks. The database search was supplemented by checking citation lists of included articles.The searches yielded 12 studies,18-29 the findings of which are outlined in Table 1. Most of the studies (8) were retrospective,18-25 along with 1 randomized control trial (RCT)26 and 3 prospective studies.27-29 The RCT compared blood component therapy with modified whole blood (mWB), that is, whole blood that goes through a leuko reduction process to inactivate platelets.26 In 4 studies, whole blood was administered in conjunction with blood component therapy and compared with use of blood component therapy alone.18-20,29 The remaining studies examined whole blood versus blood component therapy.21-28 All studies examined mortality as an outcome at either 24 hours after admission, while the patient was in the hospital, or up to 30 days after admission. Seven studies examined a secondary outcome comparing total transfusion volumes.18,20,22,24,26,27,29All evidence represents level C evidence (Table 2) when comparing whole blood with blood component therapy for significant differences in mortality and transfusion volumes. Mortality did not show a clear benefit for the whole blood groups regardless of when it was measured. All included studies used mortality as an outcome at various time frames; however, only 2 studies did not include the outcome of mortality at 24 hours.21,24 Yazer et al25 also captured mortality rates at 6 hours. Four studies indicated a reduction in mortality for patients receiving whole blood.19,21,22,28 In a fifth study, when age, injury severity score, and prehospital physiology were controlled for and patients with severe traumatic brain injury (TBI) were excluded, a 2-fold increase in survival for the whole blood group at 30 days was found.24 Jones and Frazier21 and Lee et al22 showed that whole blood was associated with a lower in-hospital mortality. However, in a multivariable analysis, after injury severity score, age, 24-hour transfusion volume, and transport time were adjusted for, LTOWB was not associated with a survival benefit.22 Hanna et al19 and Shea et al28 were the only 2 groups that identified a significant reduction in mortality within 24 hours for the whole blood groups. The 7 remaining studies showed no difference in mortality in civilian trauma patients who were resuscitated with whole blood versus blood component therapy.18,20,23,25-27,29Seven studies analyzed total transfusion volumes.18,20,22,24,26,27,29 This clinical evidence review looked at study results for total volumes only. In calculating volumes, most studies referenced the ratio that 1 unit of whole blood equaled 1 unit of RBCs, 1 unit of plasma, and 1/6 of a unit of platelets. Studies compared various time frames capturing at 4 hours and/or 24 hours, with 6 studies including 24 hours. Williams et al24 calculated post–emergency department infusion volumes without a specified time frame cutoff. Four of the studies showed a reduction in total blood product transfusion for whole blood when compared with blood component therapy.20,24,26,27 Kemp Bohan et al18 reported that the patients who received whole blood plus blood component therapy received a greater volume than did patients who received whole blood or blood component therapy alone. The remaining 2 studies showed no difference in total transfusion volumes.22,29 With these results, it is difficult to indicate definitively that whole blood offers smaller transfusion volumes to trauma patients than blood component therapy does.With most studies consisting of lower levels of evidence and showing inconsistent results, it is not plausible, on the basis of the current information, to support that whole blood is superior to blood component therapy in civilian trauma centers. There is concern for bias because only 1 study included randomization. Furthermore, the only RCT used mWB, so that could be enough of a difference for us to consider the possibility that the RCT should not have been included in this clinical review. Another limitation is the various differences in some studies examining administration of whole blood plus blood component therapy compared with blood component therapy only. From this review, it does appear that administration of whole blood in civilian trauma patients is safe and offers similar results to blood component therapy, as previous studies have indicated.14-16 If a trauma center has access to be stocked with whole blood, it is a reasonable choice to acquire and use it. A large RCT using exception from informed consent as a multisite study is needed to reduce bias and provide consistency in measuring the primary outcome of mortality at 24 hours, in the hospital, and at 30 days. Secondary outcomes could include total transfusion volume, complications, intensive care unit length of stay, and hospital length of stay.The author thanks Jerry Carlson, ms, ahip, and Monica Lasarre, mba, mt(ascp)sbb, for assisting with the literature search.