In vitro and in vivo measurements of human RBCs frozen with glycerol and subjected to various storage temperatures before deglycerolization and storage at 4 degrees C for 3 days.

BACKGROUND: This study was designed to assess the effects of changes in storage temperature of frozen RBCs such as might occur during a malfunction of the -80 degrees C mechanical freezer or during shipment. STUDY DESIGN AND METHODS: Fifteen participants donated blood for autologous transfusion of RBCs; all RBCs were frozen with 40-percent (wt/vol) glycerol. Five subjects received RBCs that were stored at -80 degrees C alone before transfusion. Five subjects received RBCs that were stored initially at -80 degrees C, then at -40 degrees C for 4 weeks, and finally at -80 degrees C before transfusion. Five subjects received RBCs that were stored at -80 degrees C, then at -20 degrees C for 2 weeks, and finally at -80 degrees C before transfusion. After deglycerolization, the RBCs were stored at 4 degrees C in a sodium chloride-glucose solution for 3 days before transfusion.
RESULTS: No significant differences were observed in freeze-thaw recovery, freeze-thaw-wash recovery, 24-hour posttransfusion survival, index of therapeutic effectiveness, or RBC ATP levels. Greater hemolysis and reduced RBC K+ levels were observed in the units stored at -80 degrees C/-40 degrees C/-80 degrees C and in those stored at -80 degrees C/ -20 degrees C/-80 degrees C compared with the units stored at -80 degrees C alone, but these differences did not affect the 24-hour posttransfusion survival.
CONCLUSIONS: The results of this study indicated that RBCs frozen with 40-percent (wt/vol) glycerol can be stored at -40 degrees C for 4 weeks or at -20 degrees C for 2 weeks between periods of frozen storage at -80 degrees C with satisfactory results.