HALF-STRENGTH CITRATE CPD COMBINED WITH A NEW ADDITIVE SOLUTION FOR IMPROVED STORAGE OF RED-BLOOD-CELLS SUITABLE FOR CLINICAL USE

Currently used systems for red blood cell (RBC) collection and storage for transfusion have the disadvantage that the RBC 2,3-bisphosphoglyc erate (BPG) concentration is depleted within two weeks of storage, res ulting in a left-shift of the oxygen dissociation curve and a temporar ily impaired capacity to deliver oxygen. We have studied the effects o n red cell metabolism, morphology and in vivo recovery of 49-day stora ge of RBC, with collection in half-strength citrate CPD (0.5CPD) and s torage in an additive solution containing citrate,adenine, mannitol, p hosphate and glucose (RAS2). Traditional CPD-SAGM was used for compari son. Component preparation was performed after an initial holding peri od of the whole blood at ambient temperature for 8 h. The BPG concentr ation in 0.5CPD-RAS2 RBC was 0.633+/-0.120 mol (mol Hb)-1 as compared to 0.454+/-0.138 mol (mol Hb)-1 in CPD-SAGM RBC which implied a decrea se to 67 and 48% of normal concentration, respectively. The mean RBC B PG concentration was maintained at the initial level for 28 days in th e new system but decreased to very low levels within 14 days in the co ntrols. The total adenine nucleotides were well maintained in both sys tems, adenosine triphosphate slightly better in the new system. Hemoly sis after 49 days was 0.35+/-0.21% in the new system and 0.72+/-0.25% in the controls (p<0.001). The morphology was better maintained in the new system (p<0.001). The 24-hour posttransfusion survival of 49-day stored RBC was 78.9+/-7.1%. The membrane leakage of sodium and potassi um was not significantly different in the two systems, The concentrati on of inorganic phosphate (Pi) in the extracellular fluid of 0.5CPD-RA S2 RBC was initially 7.1+/-0.8 mmol l-1. It decreased to approximately 5.5 mmol l-1 during the first 2 weeks of storage and then slowly incr eased to 9.4+/-0.9 mmol l-1 on day 49. Pi in the CPD-SAGM controls was low initially but rose to 6.2+/-0.4 mmol l-1 at the end of storage. T he new system offers clearcut advantages as compared to traditional sy stems and does not seem to raise any serious clinical objections again st its use even in massive transfusions.