Modify washing solutions in the process of deglycerolization in ACP 215 and storage at 4°C in 0.9% sodium chloride in 24h.

BACKGROUND: The ACP 215 was a functional closed system for preparing glycerolized and deglycerolized RBCs, CSBT had approved the technique of long term storage glycerolized rare blood lower than -65°C, and then deglycerolized by this machine. From the manual method to use ACP 215, Chinese blood banks chose 9% sodium chloride and 0.9% sodium chloride in deglycerolization process, while the AABB guideline prescribed that 12% sodium chloride and 0.9% sodium chloride-0.2% glucose were acceptable in washing step of ACP 215. In addition, 0.9% sodium chloride was the only solution which was permitted by CSBT to be added into postwash RBCs, while in America many kinds of additive solutions like AS-3 could be added into postwash RBCs and stored at 4°C for 14 days. Changes of washing solutions and preservation solution were much different from the original procedure of ACP 215 approved by the FDA. It was necessary to assess the quality of deglyceroled and postwash RBCs by this modified process in ACP 215 in China.

STUDY DESIGN AND METHODS: Two-unit whole bloods were collected from each volunteer and preserved in CP2D for anticoagulant. It was then centrifuged to separate the plasma, and suspending RBCs were stored at 4°C in MAP for 6 days. Each unit of RBC was transferred to a 1000-ml PVC plastic bag, an improved procedure including the single-disposable glycerolization set in an automated, functionally closed system (ACP 215, Haemonetics) was used to glycerolize RBC with 40% (wt/vol) glycerol, then frozen at -80°C. Two modified washing solutions of 9% sodium chloride and 0.9% sodium chloride were used to deglycerolize the same RBCs with single disposable deglycerolization set in ACP 215. The deglycerolized RBCs were stored at 4°C in 0.9% sodium chloride for 24h.

RESULTS: The freeze-thaw recovery value was 95.3±1.8% (mean±SD); the freeze-thaw-wash recovery value was 82.3±5.94% (mean±SD); the residure glycerol was 6.1±1.66 mg/dl (mean±SD), storage at 4°C in 0.9% sodium chloride within 24h after deglycerolization the supernatant Hb was 43±12 mg/dl (mean±SD); the hemolysis rate was 0.2±0.1% (mean±SD); the supernatant potassium level was 4.03±0.81 mM (mean±SD); and the postwash units were negative for both aerobic and anaerobic bacteria.

CONCLUSION: The postwash of deglycerolized RBC had an acceptable FTW recovery value, and stored in 0.9% sodium chloride for 24h at 4°C, had an acceptable hemolysis. Modified washing solutions of 9% sodium chloride and 0.9% sodium chloride and without any of preservation had not affected the quality of frozen RBCs prepared in ACP 215 and postwash stored at 4°C in 0.9% sodium chloride within 24h.