Blood transfusion rates in the care of acute trauma

BACKGROUND: Ten to 15 percent of all RBCs are used in the care of injury. Understanding patterns of RBC use is important. Routine resource allocation, planning for mass casualty situations, designing research, and optimizing triage all can be usefully informed. STUDY DESIGN AND METHODS: Blood Bank and Trauma Registry records were linked to produce a transfused blood product list for each patient directly admitted from the scene of injury to a large Level 1 trauma center in calendar year 2000. Categorical associations between demographic data, Injury Severity Score, transfused products, and outcome were sought. Special attention was paid to the groups receiving uncross-matched RBCs and more than 10 units of RBCs. RESULTS: Eight percent (479/5645) of acute trauma patients received RBCs, using 5219 units and sustaining an overall mortality of 27 percent. Sixty-two percent of RBCs were given in the first 24 hours of care. Three percent of patients (147 injured) received more than 10 units and received 71 percent of all RBCs given. Mortality in this cohort was 39 percent. Ninety percent of the patients who received more than 10 units of RBCs received plasma, and 71 percent received PLTs. CONCLUSIONS: A small number of patients receives most of the blood products used in the treatment of injury. Transfusion of more than 10 units of RBCs identifies a subgroup where most patients received plasma and PLTs to treat actual or anticipated dilutional coagulopathy. There is no clear threshold beyond which blood use is futile.