Comprehensive Evaluation of Pooled Red Blood Cell Saline Suspensions Used in Routine Blood Typing: A Resource Optimisation Laboratory-Based Study

Abstract

Preparation of 2–5% pooled A, B, and O red cell suspensions (RCS) in 0.9% normal saline (NS) is a routine and essential practice in most blood centres to ensure accurate reverse/plasma testing while performing ABO and Rh(D) blood typing [1]. These standardized RCS form the backbone of immunohematology (IH) testing because of their consistent antigen expression, reproducibility, and minimal background reactivity [2,3]. Despite their widespread use, the requirement to prepare RCS fresh each day is both labour intensive and resource-consuming, particularly in high-volume transfusion laboratories. Current literature offers limited data on the biological and functional stability of 5% pooled RCS stored under controlled refrigeration [4]. Evidence-based guidance on safe reuse duration is lacking, even though such a protocol could substantially reduce workload, reagent consumption, and operational costs without compromising test accuracy. This study, therefore, primarily aimed to determine the stability and reusability window of 5% pooled RCS prepared in 0.9% NS when stored at 4 ± 2°C. Secondary objectives included assessing agglutination strength, hemolysis, pH changes, red cell morphology, and sterility over the storage period to establish a scientifically validated reuse protocol for routine IH laboratories.