Pragmatic O-Positive Whole-blood RandoMizaTion in male trauma Patients (POWeR-MTP)

Abstract

Purpose: Hemorrhage is a significant cause of trauma-related death. Low-titer O-positive whole blood (LTOWB) is an alternative to component therapy (CT) [packed red blood cells (PRBC) and fresh frozen plasma (FFP)]. We evaluated if LTOWB reduces transfusion requirement or mortality.

Methods: Adult male trauma activations requiring uncrossmatched transfusion in the emergency department underwent nonblinded 24-hour block randomization to receive uncrossmatched LTOWB or CT in the emergency department (ED). Female patients, children, and known prisoners were excluded. If LTOWB was not available, CT was used. Primary outcome was transfusion requirement in patients surviving ≥ 24 h, with a subset analysis for patients undergoing hemorrhage control interventions (HCI). Dichotomous variables were evaluated with Chi-Square testing and continuous outcomes with Student's T-test.

Results: Overall, 199 patients were randomized (52 LTOWB, 147 CT); 36 patients (12 LTOWB, 24 CT) were excluded post-randomization for mortality within 24 h. The remaining 40 LTOWB and 123 CT patient cohorts had similar age, Glasgow Coma Scale, Injury Severity Score, heart rate, systolic blood pressure, and temperature. LTOWB patients received 1.4 ± 0.75 LTOWB units. LTOWB patients trended toward less transfusion (PRBC [3.8 ± 5.6 vs. 5.7 ± 6.2 units, p = 0.077], FFP [2.3 ± 3.8 vs. 3.5 ± 4.3 units, p = 0.088], and CRYO [0.13 ± 0.34 vs. 0.28 ± 0.68 units, p = 0.061]). Mortality was similar (LTOWB:10.2% [4/39] vs. CT:10.5% [13/123], p = 0.956). LTOWB patients undergoing HCI had less transfusion than CT patients (PRBC [3.9 ± 5.1 vs. 7.4 ± 7.2 units, p = 0.013]; in the HCI cohort the differences were even more pronounced when severe traumatic brain injury (TBI) deaths were excluded (PRBC [3.0 ± 3.6 vs. 7.4 ± 7.2 units, p < 0.001], FFP [2.1 ± 2.3 vs. 4.5 ± 5.2 units, p = 0.005]).

Conclusion: LTOWB is associated with reduced PRBC transfusion in patients undergoing HCI, and a trend toward decreased PRBC, FFP, and CRYO transfusion in all patients.

Trial registration: ClinicalTrials.gov (NCT05081063), posted 10/18/2021.

Keywords: Component therapy; Low-titer O-positive whole blood; Massive transfusion; Traumatic hemorrhagic shock.

Fig. 1

Patient Randomization and Exclusion Schema. Adult male trauma patients who were the highest-level trauma activations were enrolled at the time that uncrossmatched blood transfusion was felt to be indicated by the trauma surgeon. Blocks A and B alternated every 24 h, with CT given during Block A and LTOWB given during Block B. After the supply of LTOWB was exhausted during Block B, further transfusion was given as 1:1:1 transfusion using CT. If no LTOWB was available during Block B, CT was used. Deaths in the ED and within 24 h of arrival were specifically excluded as the primary endpoint of transfusion requirement would be affected by survivor bias if early mortalities were not excluded. The final number of patients in the two groups was imbalanced due to supply constraints of LTOWB, resulting in a significant number of patients defaulting to CT

Fig. 2

Types of Hemorrhage Control Interventions Performed (some patients received multiple interventions). The operative or interventional procedures that were performed in the CT and LTOWB groups to achieve hemorrhage control are tabulated above