T.N. Coaston1, A. Vadlakonda1, S. Mallick1,2, S.S. Ali1, E. Elkins1, N. Cho1, A. Tillou2, G. Barmparas3, P. Benharash1,2 1David Geffen School Of Medicine, University Of California At Los Angeles, Cardiovascular Outcomes Research Laboratories (CORELAB), Los Angeles, CA, USA 2David Geffen School Of Medicine, University Of California At Los Angeles, Surgery, Los Angeles, CA, USA 3Cedars-Sinai Medical Center, Trauma, Los Angeles, CA, USA
Introduction: While potentially lifesaving, massive blood transfusions consume valuable resources while subjects requiring large-volume resuscitation face increased risk of mortality. The present study sought to characterize the association of transfusion volume and mortality in a national cohort of patients with severe blunt or penetrating trauma.
Methods: Adult patients (≥18) with severe injuries (Abbreviated Injury Severity [AIS] ≥3 for any body region) receiving packed red blood cell (pRBC) transfusion were identified in the 2020-2021 Trauma Quality Improvement Program (TQIP) database. Per convention, one unit of blood was defined as 300mL. Patients were stratified into Blunt and Penetrating trauma groups. A multivariable logistic regression was constructed to evaluate the association between pRBC transfusion volume within the first 4 hours of hospitalization and mortality. Furthermore, the presence of a nonlinear relationship was explored using restricted cubic spline analysis.
Results: Of 71,945 patients, 64.5% experienced severe blunt trauma. Compared to Penetrating, Blunt were more commonly older (48 [31-64] vs 31 [24-41] years, p<0.001), female (31.6 vs 13.1%, p<0.001), and White (68.8 vs 34.2%, p<0.001). Additionally, patients with blunt injuries had a higher median Injury Severity Score (ISS) (26 [17-35] vs19 [13-26], p<0.001) and received a lower volume of pRBC’s (2 [1-5] vs 3 [1-7] units, p<0.001).
Following risk-adjustment, several factors including penetrating trauma (β 1.37, 95% Confidence Interval [CI] 1.22-1.52), higher ISS (β 0.10 per unit, 95% CI 0.09-0.10) and abdominal AIS ≥3 (β 2.16, 95% CI 1.98-2.33), were associated with increased transfusion volume. Both penetrating mechanism (Adjusted Odds Ratio [AOR] 1.42, 95% CI 1.32-1.54) and increasing transfusion volume (AOR 1.09 per unit, 95% CI 1.08-1.09) were linked with increased odds of death. Additionally, a significant interaction between trauma type and units of pRBC’s transfused was identified (p<0.001). On cubic spline analysis, the volume of blood transfused associated with a 50% risk-adjusted mortality was lower for blunt trauma compared to penetrating (Figure).
Conclusion: Our findings suggest that there are distinct risk profiles regarding transfusion for patients sustaining blunt versus penetrating injuries. The present study offers insight into patient risk stratification and considerations of futility in the setting of large volume transfusion.