(P-TS-67) Platelets Transfused >5ml/kg/hr In Pediatric Patients Increases Occurrence of Allergic Transfusion Reaction

Background/Case Studies: The generally accepted transfusion rate of RBCs in hemodynamically stable pediatric patients is 5ml/kg/hr. There is currently no accepted transfusion rate of platelets in the same population, however, the Technical Manual (20th ed) suggests 2-3ml/min to a maximum of 300ml administered over 1-2 hrs for adults. Due to variability in platelet volume of partial and whole apheresis units, transfusing a volume over a fixed time versus a rate can result in adverse reactions. These typically present as allergic with mild symptoms, but can require medication and future blood product modification, or may be severe. The benefits of rapid platelet transfusion to clinic workflow and the patient should be weighed against the risks. We describe our institutional experience with platelet transfusion rates and occurrence of Allergic Transfusion Reaction (ATR).

Study

Design/Methods: Patients with suspected ATR associated with platelets at a large multi-site Pediatric Hospital in the Southeastern USA between March 2022 and February 2023 were identified. All patients meeting the NHSN Biovigilance Component Hemovigilance Module Surveillance Protocol definition for ATR for platelet transfusions were included. An IRB approved retrospective EMR review was performed to collect demographics, transfusion history and clinical course. Prior history of ATR was not considered.

Results/Findings: Of the total platelet transfusions (n=6459), there were 42 ATRs in 31 unique patients reported by the clinical team and confirmed by Transfusion Services. Of the ATRs, platelets in 16.6% of the events were washed or PAS. Twenty-three ATRs (54.8%) occurred in the same patient only once during the reporting period. Twenty-six of 42 ATRs (61.9%) had a platelet transfusion rate >5ml/kg/hr and/or >240ml/hr. Seven of those 26 ATRs (26.92%) were both >5ml/kg/hr and >240ml/hr. The average rate of transfusions > 5ml/kg/hr and/or >240ml/hr was 10.18ml/kg/hr (5.07-21.97ml/kg/hr) and 346.72ml/hr (252.9-988.2ml/hr) respectively. When platelets were run >5ml/kg/hr and/or >240ml/hr, allergic reaction occurred 1.1% of the time compared to 0.4% of the time in patients receiving products at ≤5ml/kg/hr and/or ≤ 240ml/hr (p < 0.01).

Conclusions: To our knowledge, this is the first report of platelet transfusion >5ml/kg/hr correlating to allergic complications, specifically in a pediatric patient population. The greatest limitation to this retrospective chart review is self-reporting of suspected ATR for investigation. Additionally, patients receiving pre-medication for transfusion were not excluded. These limitations are likely contributors to lower numbers of ATR reporting in both transfusion rate groups. Determining the cost savings and benefits of platelet transfusions >5 mL/kg/hr will require a future prospective study.

Importance of research: There is scarce data to support transfusion rate recommendations for platelets in the pediatric patients. Transfusing a variable volume in partial and whole apheresis platelet units over a set time in patients with a broad size/weight range can result in transfusion reaction; specifically, Allergic Transfusion Reaction. ATR is generally mild but can result in unnecessary use of pre-medication and future product modification, associated with cost and delay in delivery of care respectively.