Acid-citrate-dextrose

They found that the mixture offers better red blood cell survival than the then state-of-the-art, MRC 1940 (trisodium citrate plus glucose).

A later improvement was CPD with adenine (CPDA-1), which boosted RBC survival to five weeks when combined with plastic bags.

[4] Although human blood is generally stored using newer formulations, the uptake of such technology is slower in veterinary medicine.

[8] Citrate, typically in the form of ACD solutions, is now preferred over heparin because it is cheap, safe, and cleared out of the system faster.

Heparin is still used for high-volume procedures, as infusing too much citrate with the returned blood can cause toxicity from the chelating action, mainly hypocalcemia.