The anticoagulant activity of enoxaparin sodium during on‐line hemodiafiltration and conventional hemodialysis

AbstractTo study and compare the anticoagulant activity of enoxaparin sodium during on‐line hemodiafiltration (OL‐HDF) and conventional hemodialysis (C‐HD). Enoxaparin was administered as an anticoagulant to 21 hemodialysis patients at the beginning of a single 4‐hour OL‐HDF session as an intravenous bolus dose of 80 mg/kg. On‐line hemodiafiltration was performed using a high‐flux polyester polymer alloy dialyzer and a total of 18 L replacement fluid (session A). One week later, the study was repeated in the same patients during a single 4‐hour session of C‐HD using a low‐flux polysulfone dialyzer (session B). Blood samples for the measurement of Hb, blood urea and nitrogen (BUN), activated partial thromboplastin time (APTT), and anti‐Xa levels were taken before each study session and 5‐minute postdialysis. In 13 more patients, the same study was performed during OL‐HDF using a high‐flux polysulfone dialyzer (session C). No differences were found between sessions A, B, and C when predialysis values for Hb, BUN, APTT, and anti‐Xa were compared. The mean postdialysis APTT and anti‐Xa values were 32.5±3.8 seconds and 0.19±0.11 IU/mL, respectively, in session A, 39.0±5.0 seconds and 0.71±0.17 IU/mL in session B, and 33.8±3.1 seconds and 0.35±17 IU/mL in session C (A vs. B, P<0.0001, for both parameters, A vs. C, P<0.003 for anti‐XA, and B vs. C, P<0.005, for both parameters). The anticoagulant activity of enoxaparin sodium is decreased significantly during a 4‐hour OL‐HDF session compared with to a similar session of C‐HD. The degree of the reduction seems to depend on the dialyzer's membrane.