Children's National Hospital Washington D.C, District of Columbia, United States
Background/Case Studies: ABO mistransfusion remains a highly preventable cause of morbidity and mortality. The advent of electronic positive patient identification (ePPID) barcode systems for collecting compatibility samples has led to significant improvements in patient safety. AABB Standard 5.14.8 permits retesting of the same sample when collected using ePPID to satisfy the requirement for two independent ABO determinations. However, this approach is not effective in detecting wrong blood in tube (WBIT) events attributed to armbanding or scanning errors.
Following transition to a new Laboratory Information System (LIS) in September 2022, our transfusion service began requiring two separately collected samples for all recipients without historic ABO typing regardless of collection method. A new electronic specimen collection software module was introduced concurrently. Our expectation was for initial and retype samples to be collected on separate occasions with specific exceptions (e.g. emergency department). In these cases, we allowed collection of both samples using the same vascular access with a minimum interval of 1 minute between collection times. The goal of this study was to evaluate our ePPID sample rejection and WBIT detection rates after implementation of this new policy.
Study
Design/Methods: Data was analyzed from patient samples submitted to the transfusion service laboratory (TSL) from January 2018 through March 2025. Specimen rejection rates were calculated as a percentage of the total number received on an annual basis. Rates of missing or inappropriately timed electronic signatures and WBIT events were analyzed to determine the impact of the described policy changes.
Results/Findings: A total of 67,896 samples were received during the study period. Approximately 150 per year (excluding 2025) were unacceptable for compatibility testing; on average, 15.7 were rejected due to missing electronic signatures. Starting in 2022, this number increased significantly to 24 and an additional 22 samples were rejected per year in 2023 and 2024 for failure to timestamp the initial and retype specimens at least 1 minute apart. During the same period, detection of WBIT events also increased from 0 to 2 per year in 2022 and 2023. The overall rejection rate reached an all-time peak (4.42%) in 2023 but subsequently declined back to near-baseline levels in 2024.
Conclusions: Implementation of a strict two ABO sample policy at our pediatric institution has been challenging due to limitations on blood draw volume based on body size and negative impact on patient satisfaction. We observed an initial increase in specimen rejection rate due to a change in electronic specimen collection workflows as well as an increase in WBIT errors which may previously have gone undetected. With ongoing process improvement interventions, these rates have stabilized in subsequent years.
