Red blood cell additives
Basic, Organ-Based and Clinical Sciences
Over the years, several chemicals have been added to pRBCs to increase their shelf life from 14 days to the current 42. Presently, all units of pRBCs are stored between 1-6 °C and the anticoagulant CPDA-1 is added. CPDA-1 is comprised of:
• Phosphate, which functions as a buffer and a source of phosphate for production of ATP
• Dextrose, a source of energy for the RBCs
• Adenine, which allows the RBCs to resynthesize ATP, further extending pRBC shelf life
The addition of CPDA-1 alone to RBCs extends the shelf life to 35 days, but this has been extended further to 42 days with the addition various other additives.
• SAGM (Saline, adenine, glucose, mannitol) solution is the most widely used additive worldwide and is extensively used in Europe, but is not approved for use in the US. The mannitol acts as a free radical scavenger and membrane stabilizer.
• AS-1 (Adsol) and AS-5 (Optisol) are a variant with identical component as SAGM in differing concentrations, and are extensively used within the US.
• AS-3 is another variant of SAGM with citrate and phosphate but no mannitol. It is approved for use in the US and Canada.
• MAP and PAGGSM are two other additives use in Japan and Germany, but are not FDA approved