Long-term citrate anticoagulation in chronic hemodialysis patients

In some cases, long-term (>3 months) citrate anticoagulation is needed in maintenance hemodialysis patients due to a persistent bleeding risk. In this retrospective observational study, we present our experience and assess its safety and effects on mineral and bone disorder parameters. Sixteen patients (mean age 67 ± 15 years) were treated with long-term citrate anticoagulation. The indications were: recurrent gastrointestinal bleeding in nine patients, heparin-induced thrombocytopenia, retroperitoneal hematoma, chronic subdural hematoma, proliferative diabetic retinopathy, vascular malformations in the brain in one patient, and others in two patients. Metabolic complications and intact parathyroid hormone (iPTH) were analyzed. Citrate anticoagulation was performed for 4 months to 6.3 years (median 12 months). Ionized calcium was stable during the procedures; hypocalcemia (<0.9 mmol/L) was rare (2.1% of procedures), and there was one case of severe symptomatic hypocalcemia. There were no clinically significant acid-base disturbances and no clotting problems. In the short term (1-3 months after starting citrate), the iPTH increased in 73% of patients (from 325 ± 310 to 591 ± 793 pg/L, P = 0.11, N = 11). In the long term (1-2 years), an increase in iPTH was observed in 3/6 patients. The time period (before/after starting citrate) was a significant predictor of iPTH using main-effects anova (P < 0.001). To conclude, long-term citrate anticoagulation in chronic hemodialysis patients is safe. Mild hypocalcemia during dialysis with citrate anticoagulation may contribute to a short- and long-term increase in iPTH in these patients. Further studies on long-term citrate anticoagulation are necessary.