Comprehensive analysis of citrate effects during plateletpheresis in normal donors

BACKGROUND: Although plateletpheresis procedures are generally well tolerat ed, the clinical and metabolic consequences associated with rapid infusion of up to 10 g of citrate are underappreciated, and a comprehensive descript ion of these events is not available. STUDY DESIGN AND METHODS: Clinical and laboratory changes were studied in s even healthy donors undergoing three 90-minute plateletpheresis procedures each, at continuous, fixed citrate infusion rates of 1.1, 1.4, and 1.6 mg p er kg per minute. RESULTS: Serum citrate levels increased markedly with increasing citrate in fusion rates and did not achieve a stable plateau. As citrate infusion rate s increased, the total volume processed and platelet yields also increased, but donor symptoms became more severe. Ionized calcium (iCa) and ionized m agnesium (iMg) concentrations decreased markedly, by 33 and 39 percent belo w baseline, respectively, at a citrate rate of 1.6 mg per kg per minute. In tact parathyroid hormone levels were higher at 30 minutes than at later tim e points, despite progressive decreases in iCa and iMg. Urine citrate, calc ium, magnesium, sodium, and potassium concentrations and urine pH values in creased markedly during all procedures. CONCLUSION: Marked, progressive increases in serum citrate levels occur dur ing plateletpheresis, accompanied by symptomatic decreases in iCa and iMg, with significantly increased renal excretion of calcium, magnesium, and cit rate.