The resulting pH of fresh frozen plasma for clinical use, collected by plasmapheresis from blood donors is influenced by the type of anticoagulant solution and its ratio with the donor's blood. The authors describe the use of three anticoagulant solutions with a different sodium citrate concentration and different ratios of donor blood. As compared with the physiological range of pH of the blood, the resulting pH value of the collected plasma, when using ACD-A and AB-16 solutions, varies within the range classified as acidosis, i.e. less than 7.36. When using a 4% sodium citrate solution the plasma pH value is in the area evaluated as alkalosis. The authors discuss indications for administration of fresh frozen plasma in clinically serious diseases and the influence of administration of this transfusion preparation on the acid-base balance as the transfusion recipients are threatened by the development of metabolic acidosis. Maintaining the pH value of fresh frozen plasma slightly above the physiological range of blood pH prevents in particular during massive plasma transfusions the possibility of deterioration of acidosis or its development.

Keywords: Anticoagulants /pharmacology/; Blood /drug effects/; Blood Donors; Humans; Hydrogen-Ion Concentration; Plasmapheresis