(P-BB-10) Alternative Wash Procedure Implementation During COVID Pandemic Supply Chain Disruptions

Background/Case Studies: The supply chain disruptions that occurred during the pandemic impacted the manufacturers of processing sets and saline used in automated cell washing instruments, which led to disruptions in the manufacturing of washed and deglycerolized products. The immediate availability of washed red blood cell (WRBC) products is critical for neonates and/or patients with severe allergic or anaphylactic reactions to transfusions. In response, a validation of a manual method for manufacturing WRBC using only 250mL of 0.9% saline was performed. This method would minimize saline use and maintain processing set inventory for the deglycerolization of frozen red cells and for washed platelets.

Study

Design/Methods: The blood center manually washed whole blood derived red blood cell (RBC) units at the main manufacturing sites. It was anticipated volume of products would approximate 60 units per month, therefore to achieve 95% confidence with a 5% interval, 52 units were required for validation. For each RBC the quality control testing included a pre-total protein (TP) from the original unit and a post-wash sample for HCT and TP testing. The manual wash procedure began with aseptically adding 250 ml of 0.9% saline to the RBC unit; mixing was performed and a 1000 ml transfer bag was sterile connected to the unit. The two bags were placed in a cup-holder of a refrigerated -4°C component centrifuge, balanced and spun at 4500 RPM, with an acceleration time of 3:34, and a deceleration time of 2:00. Following centrifugation, the supernatant saline was expressed into the attached transfer 1000mL bag, leaving the single washed red cell in the original container.

Results/Findings: The expected quality control results for a washed red cell are post-HCT result of 65%-80% and post-TP of > 0.5 g/u. During the validation period 57 RBCs were manufactured with an average post-HCT value of 66.4%, ranging from 54.0% to 78.6%, with a standard deviation of 5.6%. Four RBCs (7%) had unacceptable post-TP results and 18 RBCs (31%) had post-HCT results of less than 65%, with an average of 59.7%. One of these RBCs had an outlier post-HCT value of 47.1%.

Conclusions: The implementation of the manual wash method was effective in addressing the supply chain disruptions and ensuring the availability of washed red blood cell products for patients in critical need. Despite having quality control issues with some units, the benefits of having available washed RBC products outweighed the risk of RBC discards. Therefore, the blood center would consider the implementation of this method in a similar situation.

Importance of research: Having the agility to quickly implement new procedures and techniques within the blood center has become more critical than ever due to recent uncertainties in both societal and economic environments. This abstract provides a guidance on how a new washed red cell unit procedure was implemented during supply chain disruptions.