(P-TS-76) Low Titer O Whole Blood (LTOWB) Utilization and Safety Outcomes at Two Adult Level 1 Trauma Centers

Background/Case Studies: In the last decade, there has been renewed interest in the use of Low Titer O Whole Blood (LTOWB) for hemostatic resuscitation in military and civilian trauma. While LTOWB use has also been expanded to bleeding non-trauma patients, there is a paucity of data on the safety and efficacy of LTOWB use in this patient population. A safety study of non-trauma patients that required resuscitation with LTOWB was conducted at two Level 1 trauma hospitals.

Study

Design/Methods: Demographic, clinical, laboratory, and transfusion data was collected for non-trauma bleeding patients who received LTOWB between January 1, 2018, and June 30, 2024.The type, volume, and timing of both LTOWB and component therapy were also collected. Pre- and posttransfusion clinical laboratory data (Hgb, Hct, LDH, haptoglobin, total bilirubin, indirect bilirubin, direct bilirubin, Cr, BUN, GFR), transfusion reactions, and post-transfusion sepsis were collected and assessed as potential indicators of transfusion safety. Safety outcomes were specifically compared between group-O and non-group O recipients of LTOWB.

Results/Findings: After applying all exclusion criteria, 319 unique patients with a total of 320 transfusion episodes were included in the analysis cohort, which was 65% (207/320) male and had a median (IQR) age of 64 years (54.5-75). The indication for transfusion was due to a GI cause in 189 episodes and cardiovascular in 77. The median number of blood products transfused per episode were 2 (1-2) LTOWB, 2 (0-5) RBCs, 0 (0-4) plasma, 0 (0-2) platelets, and 0 (0-0) units of cryoprecipitate. Survival of patients at 24 hours and 30 days after transfusion was 79% and 54%, respectively. The data showed no statistically significant difference in safety outcomes, such as renal failure and hemolysis, as reflected by similar changes in pre- and post-LTOWB transfusion laboratory parameters between group-O and non-group O patients (Table). There were no documented transfusion reactions or cases of transfusion-associated sepsis associated with the transfusion of LTOWB. Of the 16 RhD-negative patients with negative antibody screens prior to transfusion who received only RhD positive LTOWB, 1 developed new anti-D alloantibodies, detected 14 days post transfusion.

Conclusions: This retrospective review of LTOWB transfusion in non-trauma bleeding patients found a low rate of adverse outcomes related to the transfusion of LTOWB consistent with the current literature on trauma recipients of LTOWB. Continued investigation into the safety and efficacy of LTOWB resuscitation in non-trauma patients can further expand the utility of this product to additional patient populations and ensure improved outcomes through timely and safe resuscitation efforts.