Hemodialysis does not induce detectable activation of the contact system of coagulation

Abstract Introduction Hemodialysis does not induce detectable activation of the contact system of coagulationSystemic anticoagulation is administered during hemodialysis to prevent clotting of the extracorporeal circuit. The role of contact system activation in thrombin generation during hemodialysis using current era dialyzer membranes is unknown. Methods We performed a single center randomized crossover study. Ten patients treated with hemodialysis underwent 3 standardized hemodialysis sessions. For every patient, each session was performed with a different type of dialyzer membrane (polyphenylene [PP], polymethylmetacrylate [PMMA], polyethylenimine-coated polyacrylonitrile [AN69ST]). Blood samples were collected before and 5, 15, 30, 90 and 240 minutes after blood pump start to evaluate coagulation activation (thrombin-antithrombin complex [TAT], Prothrombin Fragment 1+2 [PF1+2], FXIIa, kallikrein, FXIa). Plasma of healthy volunteers (n=20) was used as a reference. Results Baseline TAT and PF1+2 levels were higher in hemodialysis patients as compared to healthy controls (median [IQR] for TAT: 3.3 [2.9-4.2] versus 2.4 [2.3-2.5] μg/L [p=0.0002] and for PF1+2: 647 [478-737] versus 138 [125-254] pmol/L [p Conclusion Routine hemodialysis using systemic heparin anticoagulation induces coagulation activation without measurable contact system activation.