A simple visual clots score system allows to reduce the dose of low molecular weight heparin in hemodialysis

Prevention of HD extracorporeal circuit clotting with LMWH is mandatory for adequate of hemodialysis treatment. The LMWH recommended dosage is 100-50 IU/Kg/HD given in a single pre-dialysis bolus but LMWH has dose-dependent side effects and clinical tools are needed to optimize the dose with the aim of reducing it. We have used a visual clots score identifying the post treatment clotting status of the hemodialysis circuit. It is based on the presence or absence of clots in dialyzer and/or in arterial and/or in venous HD circuit chambers at the end of the HD session with a score ranging from 0 (no clot) to 3 (clots in the 3 segments of the HD circuit Fig 1). Our aim was to modify the standard and routinely fixed dose of LMWH according to the average monthly score (reduction if clots score ≤ 0,5; increment if > 1,5). We then compared the average total dose administered to 90 HD patients one year before and one year after the introduction of the scoring system. The average dose of LMWH per single patient dropped from 64.6±18.5IU/kg/HD (equal to a total 645.457±219.488 IU/year) in 2016 to 53.6±18.3 IU/Kg /HD (equal to a total 484,492±235,546 IU/year) in 2017 (Figure2.p<0.001) without increments of the coagulation score. Our experience shows that a rather simple clots score system allows to individualize LMWH therapy, with a significant reduction of the dosage. The potential reduction of the renowned and dose-dependent side-effects of this drug should evaluated in further studies