During hemodialysis, waste products are removed from the blood by diffusion across the dialyzer membrane into an electrolyte solution known as dialysate. Dialysate is produced from acid concentrate, bicarbonate solution and water using a three stream proportioning system that mixes the acid concentrate, bicarbonate and water to produce the final dialysate. Patients are typically anticoagulated with heparin during dialysis to prevent blood from clotting in the extracorpoeial circuit. Heparin use is associated with significant risks including the possibility of bleeding, heparin induced thrombocytopenia (HIT) and contamination. For these reasons, the possibility of reducing heparin dose while maintaining HD adequacy is clinically attractive. Citrasate® is an FDA approved acid concentrate that contains citric acid (citrate) rather than acetic acid (acetate) which is traditionally used in acid concentrate. Citrate in higher concentrations is also a known anticoagulant. We are therefore conducting this study to determine whether the use of Citrasate, citric acid dialysate enables the reduction of the heparin requirements in patients undergoing hemodialysis.