975: RHD Immune Globulin Administration in Female Trauma Patients After Emergent Whole Blood Transfusion

Introduction: Emergent administration of RhD-mismatched low-titer group O whole blood (LTOWB) transfusions in females of child-bearing potential (FCP) can result in RhD alloimmunization. Per our institutional guidance, intravenous (IV) RhD immune globulin (RIG), WinRho©, for FCP (age 14-45 years old) can be dosed 9 mcg/mL of LTOWB given. IV RIG can be recommended if LTOWB was administered within the last 72 hours, there is desire for future pregnancy, and there is presence of D+ cells after LTWOB. There is limited literature investigating IV RIG in trauma FCP, therefore, this study aims to characterize IV RIG administration and its subsequent risk of hemolysis. Methods: This is a single-center, retrospective analysis conducted between August 2020 and July 2024 within the Critical Care and Trauma Institute at West Virginia University Hospitals. FCP were identified utilizing the trauma whole blood registry and further examined for FCP who received IV RIG during hospital admission. The primary objective was to evaluate IV RIG dosing and frequency. Secondary objectives examined were total LTOWB administered, time to IV RIG administration and completion, and identified markers of hemolysis. Results: A total of 13 trauma FCP were identified to have received emergent LTOWB, with five patients receiving IV RIG. Median age was 23 years old among the FCP population. All patients tested positive for D+ cells after administration of LTOWB. The median total IV RIG dose was 5000 mcg (IQR 3000-9000) with all patients receiving administrations every eight hours. The median dose of IV RIG was 8.53 mcg/mL (IQR 7.4-9.0) of LTWOB received. Median LTOWB given was two units (IQR 1-2) with median volume of 1054 milliliters (IQR 555-1214). Median time to IV RIG administration and completion was 45 hours 4 minutes and 59 hours 38 minutes, respectively. One FCP experienced markers of hemolysis following the first dose of IV RIG administration and was subsequently discontinued. Conclusions: Prevention of RhD alloimmunization via IV RIG after LTOWB in trauma FCP is an emerging treatment modality. This study provides IV RIG guidance for institutions that utilize LTOWB in FCP for emergent trauma resuscitation.