Background: Benefits of high ratios of fresh frozen plasma (FFP) to packed red blood cells (pRBC) in massively transfused trauma patients have been reported previously. This study aimed to assess the effect of higher FFP:pRBC ratios on outcome in patients receiving less than massive transfusion during acute trauma care.
Methods: The multicenter trauma registry of the German Trauma Society (2005-2008) was retrospectively analyzed for patients aged≥16 years with an Injury Severity Score≥16 who had received multiple but not massive transfusion between emergency room arrival and intensive care unit (ICU) admission, i.e., at least 4 but less than 10 pRBC units (4≤pRBC units<10). Patients who died within 1 hour after hospital admission were excluded. Three groups were analyzed according to FFP:pRBC ratio: low (<1:1, LR), balanced (1:1, BR), and high ratio (>1:1, HR). BR was defined as pRBC units=FFP units±1 FFP unit.
Results: A total of 1,362 patients met study criteria (LR=760, BR=392, and HR=210). Patient characteristics were similar among groups. For the three groups (LR, BR, and HR) sepsis was reported in 17.1%, 18.2%, and 17.6% (p=0.9), incidence of multiple organ failure was 49.1%, 47.9%, and 52.4% (p=0.6), whereas mortality was 26.8%, 21.7%, and 15.2% (p=0.001), respectively. Ongoing pRBC-transfusion after ICU admission occurred in 68.1%, 66.7%, and 53.9% (p<0.001), respectively. ICU/hospital lengths of stay were comparable between groups. Multivariate logistic regression identified a high FFP:pRBC ratio as independent predictor for survival (odds ratio, 0.52, p=0.013).
Conclusions: Trauma patients receiving less than massive transfusion might also benefit from higher FFP:pRBC ratios, as these were associated with significantly lower mortality rates and decreased blood product utilization during subsequent ICU treatment, whereas morbidity was comparable among groups. Additional prospective trials are necessary.