Studies that used a dilute citrate formulation (4%) demonstrated efficacy as an anticoagulant with minimal to no risk of bleeding in HD sessions. This study will compare effectiveness and safety utilizing 4% sodium citrate vs. heparin as a lock solution in central venous hemodialysis catheter among hemodialysis patients.

Vascular access is necessary for hemodialysis(HD) procedure. In normal situation, vascular access for HD is created in peripheral vessels. However, vascular catheter may be considered in patients without available peripheral vessels for vascular access. The characteristic of these patients include elderly, diabetes, not tolerant to vascular surgery etc.. Commonly, the HD catheter is inserted in the central vein in these population. Considering clotting condition, anticoagulant is indicated for catheter locking after HD session. In the past years, heparin is the most common solution to be used as locking solution. Nevertheless, heparin has a few disadvantages, such as systemic anticoagulation, thrombocytopenia, and bleeding risk. An alternative for anticoagulation in HD session is 4% sodium citrate. The effectiveness and safety of sodium citrate in HD sessions have been reported in clinical studies.

Characteristics of sodium citrate and safety profile Trisodium citrate acts locally as an anticoagulant by chelating ionized calcium in blood, resulting in the blockage of calcium-dependent clotting pathways. Studies that used a dilute citrate formulation (4%) demonstrated efficacy as an anticoagulant with minimal to no risk of bleeding in HD sessions. The advantageous effects of sodium citrate in HD catheter locking solution includes reducing frequency of catheter exchanges, reducing using of thrombolytic drugs, reducing hospitalization rates, and bacteremia. Regarding adverse effect of sodium citrate, hypocalcemia and other untoward outcomes are rare reported in the previous clinical studies

Inclusion Criteria:

1. Age >=20 years
2. End-stage renal disease patients who received regular HD weekly via central venous catheter for at least 3 months in outpatient clinic in Kaohsiung Chang Gung Memorial Hospital, Taiwan

Exclusion Criteria:

1. bleeding tendency
2. on radiotherapy or chemotherapy for malignancy
3. pregnancy
4. drug allergy history to citrate
5. undefined reasons for refuted participation.