Effect of citrate on ionized calcium levels during plateletpheresis procedures

Abstract

Plateletpheresis procedures are generally well tolerated by most of the donors and adverse reactions due to citrate are generally mild and easily managed. The most common apheresis‐related reaction is hypocalcemia due to citrate anticoagulation which reduces ionized calcium and magnesium levels. The levels of ionized calcium levels decrease continuously from the baseline levels till end of the procedure and restore to baseline values post‐procedure. Symptoms of citrate toxicity are dependent on various factors like rate of citrate administration, duration of citrate infusion, dilution of citrate in extracellular fluid, redistribution, rate of citrate metabolism and the rate of citrate excretion. Citrate metabolism occurs in the liver, kidney, and skeletal muscle. Donors generally tolerate up to 20% decreases in ionized calcium levels. Citrate related reactions are generally transient and selflimiting. Citrate reactions can be differentiated into mild, moderate and severe. Management of citrate reactions includes mostly procedural modifications and/or oral calcium supplementation and rarely may require intravenous calcium supplementation. In donors with citrate related hypocalcemic symptoms, unresponsive to calcium supplementation, measurement of ionized magnesium should be considered as citrate decreased the ionized magnesium levels too. Management of such donors should be done with supplementation with magnesium sulfate. Management of donor reactions will make donors experience more pleasant, thereby increasing donor return rate and maintain the donor pool.