HEMODIALYSIS WITHOUT ANTICOAGULANT - HEMOSTASIS PARAMETERS, FIBRINOGEN KINETIC, AND DIALYSIS EFFICIENCY

Background. Haemodialysis without anticoagulant is an alternative to s ystemic anticoagulation of patients at high risk of bleeding. However, reports have suggested that heparin-free haemodialysis might results in blood defibrination, and fibrin deposition in dialytic membrane wit h possible reduction in dialyser efficiency. Methods. Haemostasis para meters, fibrin-fibrinogen kinetic assessed by I-125-fibrinogen (I-125- F) turnover and I-125-fibrinogen deposition within the dialyser membra nes, and dialytic efficiency were studied in 10 stable chronic uraemic patients. Each patient was dialysed on two consecutive 4-h dialyses, once with each of two dialysis strategies: haemodialysis without antic oagulant and conventional haemodialysis using heparin as anticoagulant . Results. No significant changes were seen in mean platelet count, pl asma fibrinogen, prothrombin time, and antithrombin III during, haemod ialysis without anticoagulation, and these parameters were not differe nt from those in patients who underwent conventional haemodialysis. Co mpared with the predialysis values, a shortening of the mean aPTT from an initial mean value was noted (P<0.05) in haemodialysis without ant icoagulation at 60, 120 and 240 min. Fibrin-fibrinogen degradation pro ducts remained unchanged during conventional haemodialysis, but were i ncreased after the 30th minute of haemodialysis without anticoagulatio n (P<0.05), although all values were in normal range. The biological h alf-life of I-125-F in uraemic patients before the haemodialysis was 5 .02+/-0.43 days (control). There was a significant fall in I-125-F hal f-life during haemodialysis without anticoagulation (2.56+/-0.55 days: P<0.01) but not during conventional haemodialysis 14.77+/-0.97, NS). After use each dialyser was dismantled and I-125-F deposition within t he membranes (M#5, M#12 and M#19) was measured. During haemodialysis w ithout anticoagulation mean fibrin deposition in M# (28.71+/-10.50 x 1 0(3) counts), M#12 (26.42+/-9.06 x 10(3) counts), and M#19 (21.97+/-8. 33x10(3) counts) was greater (P<0.001) than that during conventio;al h aemodialysis (1.70+/-0.92 x 10(3), 1.33+/-0.65 x 10(3), and 1.59+/-1.0 3 x 10(3) counts respectively). However, this greater deposition of fi brin on membranes during haemodialysis without anticoagulation did not change dialyser efficiency as assessed (haemodialysis without anticoa gulation vs conventional haemodialysis) by change in serum urea (-53.9 6+/-3.38% vs -51.36+/-5.20%, NS), serum creatinine (-48.65+/-5.99% vs -49.59+/-6.65%, NS, serum potassium (-30.06+/-4.46% vs -27.64+/-2.81%, NS), serum bicarbonate (+25.91+/- 1.39% vs +24.89+/-2.59%, NS) and ha ematocrit (+3.20+/-3.99% vs 2.15+/-2.01%,NS). The mean Kt/V was simila r for conventional haemodialysis (0.870+/-0.074) and haemodialysis wit hout anticoagulation (0.873+/-0.107). Conclusion. In conclusion, altho ugh conventional haemostasis parameters remained unchanged during haem odialysis without anticoagulation, some degree of activation of coagul ation system occurs. haemodialysis without anticoagulation was associa ted with greater decline in I-125-F half-life and greater fibrin depos ition on dialyser membranes, but with no change in dialyser efficiency .