In severely injured civilian trauma patients, preemptive transfusion of low-titer group o+ non-leukoreduced whole blood promotes significantly improved 30-day survival

Abstract Introduction: Trauma is a major cause of death worldwide; yet, patients (pts) with traumatic hemorrhage are potentially salvageable, if early supply of blood components and efficient bleeding control are provided. The seminal studies, analyzing the data obtained during the Korean War, have proven safety of using whole blood in military trauma victims. Results of recently published studies demonstrate safety of low-titer group O+ whole blood (LTOWB) for civilian trauma pts. The current study evaluated impacts of immediate in-hospital transfusion of non-leukoreduced LTOWB on 30-day survival of severely injured civilian trauma pts (the study group). Methods: Since 10/2021, non-leukoreduced LTOWB units, donated by male donors carrying anti-A and anti-B antibodies with a titer <1:150 (70% of O+ male blood donors), were supplied by the Israeli National Blood Services. Two units of LTOWB are readily available in the repository of the Shock Trauma Room (STR) and another two at the Blood Bank of the Rambam Health Care Campus. Comparisons were made to the control group that included trauma pts, transfused (2017-2020) with blood components (including uncrossed, unmatched), urgently provided by the Rambam Blood Bank at patient arrival in the STR. Patient electronic medical records were reviewed for the relevant data on transfusion and 30-day outcomes in these groups. The information regarding age, gender, the trauma mechanism, the Injury Severity Score (ISS), presence of traumatic brain injury (TBI) and blood products transfused during the first 6 hours and between 6-24 hours was retrieved from the institutional database. Results:During the study period of 39 months (10.2021-31.12.2024), 752 LTOWB units were supplied to the STR repository: 600 units were transfused and the remaining 152 units (20%) were returned on day 22 post-donation to the Blood Bank and processed to packed red blood cells. The median age of LTOWB units during transfusion was 13 days (25-75 percentile 11-17 days). Of 301 civilian trauma pts, admitted due to hemodynamic instability, 15 were transfused with 3-4 LTOWB units, 173 received 2 units and 113 received 1 unit. The control group included 135 pts. Those who were dead on arrival or died within the first hour of admission (n=44) were considered ineligible for survival analysis. Pts with ISS <16 (n=51) were also excluded, as there was 100% survival in this group, irrespective of the blood product used. A total of 54 pts in both groups had TBI. In a univariate analysis, the following parameters were associated with increased 30-day mortality: age ≥65 years [OR 2.89 (95%CI 1.46-5.75); p=0.002], hemorrhagic shock [OR 2.7 (95%CI 1.55-4.7); p=0.000], blood pH ≤7.2 [OR 3.41 (95%CI 1.94-6.02); p=0.000] and TBI [OR 5.32 (95%CI 2.83-10); p=0.000]. The 30-day mortality was significantly lower in the LTWOB group than in the control group [15% vs 26%; OR 0.5 (95%CI 0.29-0.86); p=0.012]. Among pts with ISS 25-39 and no TBI, there was significant improvement in 30-day survival in the LTWOB group (95.3% vs 82.9 %), with mortality OR 0.24 (95%CI 0.07-0.87; p=0.03). Of note, among TBI pts with ISS 25-39, differences in survival rates between the groups (90% vs 33%) did not reach statistical significance due to the small number of these pts in the study (n=14). Due to the major impact of TBI on patient survival and the lack of intergroup difference in 30-day mortality (LTOWB: 42.9% vs control: 52.6%, respectively; p=0.492), an additional evaluation was performed upon the exclusion of TBI pts (n=54). Consistent with the data obtained in the pre-exclusion evaluation, the latter analysis revealed significant reduction in 30-day mortality in the LTOWB (n=189) vs control group (n=98) [10.1% vs 21.4%; OR 0.41 (95%CI 0.21-0.81); p=0.01]. In a multivariate analysis excluding TBI pts, the following factors were found to be significant for 30-day mortality: age ≥65 [OR 4.09 (95%CI 1.49-11.22; p=0.006], blood pH £7.2 [OR 4.23 (95%CI 1.95-9.18); p=0.000], LTOWB [OR 0.48 95%CI (0.23-0.99); p=0.046], ISS ≥40 compared to ISS 16-24 [OR 3.93 (95%CI 1.24-12.5); p=0.02]. Conclusion:The findings of the present study show highly significant improvement in 30-day survival among severely injured civilian trauma patients transfused with LTOWB, immediately available in the STR. This approach is safe and its utilization is associated with low discard rates of blood units. These results strongly support its application at Level 1 trauma centers.