Storage of red blood cells in alkaline PAGGGM improves metabolism but has no effect on recovery after transfusion

Additive solutions are used to limit changes that red blood cells (RBCs) undergo during storage. Several studies have shown better preservation of glucose and redox metabolism using the alkaline additive solution PAGGGM (phosphate-adenine-glucose-guanosine-gluconate-mannitol). In this randomized open-label intervention trial in 20 healthy volunteers, the effect of storage, PAGGGM vs SAGM (saline-adenine-glucose-mannitol), on posttransfusion recovery (PTR) and metabolic restoration after transfusion was assessed. Subjects received an autologous biotinylated RBC concentrate stored for 35 days in SAGM or PAGGGM. As a reference for the PTR, a 2-day stored autologous biotinylated RBC concentrate stored in SAGM was simultaneously transfused. RBC phenotype and PTR were assessed after transfusion. Biotinylated RBCs were isolated from the circulation for metabolomics analysis up to 24 hours after transfusion. The PTR was significantly higher in the 2-day stored RBCs than in 35-day stored RBCs 2 and 7 days after transfusion: 96% (90 to 99) vs 72% (66 to 89) and 96% (90 to 99) vs 72% (66 to 89), respectively. PTR of SAGM- and PAGGGM-stored RBCs did not differ significantly. Glucose and redox metabolism were better preserved in PAGGGM-stored RBCs. The differences measured in the blood bag remained present only until 1 day after transfusion. No differences in RBC phenotype were found besides an increased complement C3 deposition on 35-day RBCs stored in PAGGGM. Our data indicate that despite better metabolic preservation, PAGGGM is not a suitable alternative for SAGM because storage in PAGGGM did not result in an increased PTR. Finally, RBCs recovered from circulation after transfusion showed reversal of the metabolic storage lesion in vivo within a day. This study is registered in the Dutch trial register (NTR6492).