Optimisation and validation of washed red cell unit production

Abstract

Washed red cell concentrates (RCC) are produced by washing RCC units in a closed system at 4˚C, using isotonic saline or other solutions. Washing is done in order to remove any plasma, leucocytes, metabolites and platelets present in the red cell suspension (Grabmer et al., 2006) to prevent the occurrence of adverse transfusion reactions (Tobian, Savage, Tish, Thoman, King & Ness, 2011). The current expiry date of washed red cells is 24 hours (NBTC SOP-PP0021/.01, 2014). The objectives of this study were to extend the expiry of washed RCC units through the analysis of quality control requirement levels and sterility testing; to validate the storage limits of irradiated washed RCC units by analysing the percentage haemolysis and extracellular potassium levels of the irradiated product; and to validate the sterility of washed RCC units for bacterial growth using six known controlled micro-organisms, which shall be detected using the BacT/ALERT® microbial detection system. Through the results, it was concluded that the lifespan of washed RCC units can be extended to 7 days. The validated lifespan for irradiated washed RCC is 48 hours and they should be produced by irradiating and then washing. Saline does not inhibit the growth of Clostridium sporogenes, Candida albicans, Pseudomonas aeruoginosa, Bacillus subtilis, Aspergillus brasiliensis and Staphylococcus aureus in washed RCC.