Hemodialysis without anticoagulation: Less clotting in conventional hemodialysis than in predilution hemodiafiltration

INTRODUCTION: Hemodialysis patients with contraindication to systemic anticoagulation require a heparin-free hemodialysis technique. Among several alternatives to heparin, predilution hemodiafiltration (HDF) is often used, albeit without any confirmation of its effectiveness. METHODS: Patients hospitalized in a nephrology ICU and hemodialysed for stage 5 CKD or AKI and with contraindication to systemic anticoagulation were randomized to either standard HD with a polysulfone membrane, or to predilution HDF with the same membrane. Coagulation activation was evaluated clinically by the need for premature termination and by the measurement of D-dimers. FINDINGS: Two hundred dialysis sessions were performed in 155 patients. Survival curves showed better circuit survival in HD (P = 0.046). In HD, 12% of sessions were interrupted for coagulation versus 23% in predilution HDF (P = 0.04). DISCUSSION: Predilution HDF was associated with more premature clotting than conventional HD without improvement in dialysis duration or performance epuration indices. When aiming for a 4-hour duration session, conventional heparin-free hemodialysis can be safely proposed in most patients with high bleeding risk.