N. Merutka1, J. Williams1, C. E. Wade1, B. A. Cotton1 1McGovern Medical School at UT Health,Acute Care Surgery,Houston, TEXAS, USA
Introduction: Several US trauma centers have begun incorporating uncrossmatched, group O whole blood into civilian trauma resuscitation. Our hospital has recently added this product to our aeromedical transport services. We hypothesized that patients receiving whole blood in the field would arrive to the emergency department with more improved vital signs, improved lactate and base deficit, and would receive less transfusions following arrival when compared to those patients receiving pre-hospital component transfusions.
Methods: In Novemeber 2017, we added low-titer group O whole blood (WB) to each of our helicopters, alongside that of existing RBCs and plasma. We collected information on all trauma patients receiving prehospital uncrossed, emergency release blood products between 11/01/17 and 07/31/18. Patients were divided into those who received any prehospital WB and those who received only RBC and or plasma (COMP). Initial field vital signs, arrival vital signs, arrival lbaoratory values, and ED and post-ED blood products were captured. Statistical analysis was performed using STATA 12.1. Continuous data are presented as medians (25th-75th IQR) with comparisons performed using Wilcoxon ranksum. Categorical data are reported as proportions and tested for significance using Fisher’s exact test. Following univariate analyses, a multivariate model was created to evaluate post-arrival blood products, controlling injury severity score, field vital signs, and age.
Results: 174 patients met criteria, with 98 receiving prehospital WB and 63 receiving COMP therapy. 116 WB units were transfused in the prehospital setting. Of those receiving WB prehospital, 84 (82%) received 1 U, 14 (12%) received 2U. There was no difference in age, sex, race, or injury severity scores between the two groups. While field pulse was similar (WB: median 117 vs. COMP: 114; p=0.649), WB patients had lower field systolic pressures (median 101 vs. 125; p=0.026) and were more likely to have positive field FAST exam (37% vs. 20%; p=0.053). On arrival, however, WB patients had lower pulse and higher systolic pressures than COMP patients (TABLE). There was no difference in arrival base excess and lactate values (TABLE). However, WB patients had less ED and post-ED blood transfusions than the COMP group. A multivariate linear regression model demonstrated that field WB was associated with a reduction in ED blood transfusions (corr. coef. -10.8, 95% C.I. -19.0 to -2.5; p=0.018).
Conclusion: Prehospital WB transfusion is associated with improved arrival physiology with similar degrees of shock compared to COMP treated pateints. More importantly, WB pateints received less transfusions after arrival than their COMP counterparts.
