Comparison of the injection of low‐molecular weight heparin in the arterial vs. venous blood line for preventing extracorporeal circuit clotting during hemodialysis

Abstract

Low-molecular weight heparins (LMWH) are widely used for preventing clotting during hemodialysis (HD). Although injection in the venous blood line is recommended to avoid initial loss of LMWH through the dialyzer, LMWH is still frequently administered in the arterial blood line at the start of dialysis. This study aimed to compare the safety and efficacy of the same enoxaparin dose administered through the venous blood line or arterial blood line. We also evaluated antifactor Xa (aXa) activity according to the injection route and dialysis modalities: high-flux (HF) HD, medium cut-off (MCO) HD, and online hemodiafiltration (OL-HDF). Forty-three patients were studied over 18 consecutive dialysis sessions using a fixed enoxaparin dose (20 or 40 mg), first administered through the arterial blood line bolus and then through the venous blood line for another 18 sessions. Compared to arterial blood line administration, venous blood line bolus resulted in a significant increase in median post-dialysis aXa activity: 0.16 (0.1-0.6) IU/ml versus 0.31 (0.1-1.3) IU/ml, respectively, p = 0.006. After arterial blood line bolus of 40 mg enoxaparin, median post-dialysis aXa activity was significantly lower with OL-HDF compared to HF-HD: 0.14 (0.1-0.35) versus 0.32 (0.15-0.49), p = 0.02. A trend for lower clotting within lines and bubble trap using venous blood line bolus was observed. In conclusion, venous blood line enoxaparin injection is safe in OL-HDF patients. However, in HF-HD and MCO-HD, venous blood line injection of 40 mg enoxaparin may increase overdosing risk. Thus, aXa activity should be monitored in HF-HD and MCO-HD patients at risk of bleeding and/or on vitamin K antagonists and careful surveillance is required when administering a 40 mg enoxaparin dose through the venous blood line route.

Apply Anticoagulants after Discharge not Benefit to the Incidence of Symptomatic Thrombus in High‐Altitude Areas: A Retrospective Study

“…The reduced bleeding risk observed in our study may be attributed to the use of LMWH and new oral anticoagulants in our patients. When administered at the same dose, LMWH generally carries a lower risk of bleeding than regular heparin 20 . This can be attributed to its more targeted action on coagulation factor Xa rather than thrombin 21 .…”

“…When administered at the same dose, LMWH generally carries a lower risk of bleeding than regular heparin. 20 This can be attributed to its more targeted action on coagulation factor Xa rather than thrombin. 21 Furthermore, the newer oral anticoagulants demonstrate a relatively lower risk of bleeding than traditional oral anticoagulants while effectively preventing thrombosis.…”

Optimising the Nadroparin Dose for Thromboprophylaxis During Hemodialysis by Developing a Population Pharmacodynamic Model Using Anti-Xa Levels

“…Moreover, HDF as compared to HD removes larger molecules to a greater extent due to use of convection as compared to diffusion, which may also explain the difference in nadroparin clearance between these types of hemodialysis [6,30,31]. Some studies reported a significantly lower anti-Xa level in HDF versus high-flux hemodialysis (HF-HD), indicating a higher nadroparin clearance in HDF versus HF-HD [32,33]. However, Sridharan et al reported no difference in required LMWH dose to achieve adequate anti-Xa levels between HDF and HF-HD, suggesting no effect of dialysis mode on nadroparin clearance [34].…”

“…Current guidelines recommend dosing nadroparin based on the patient's body weight [5,6]. However, it has been stated before that higher nadroparin doses are needed in patients treated with HDF and that the type of dialyzer affects the required nadroparin dose [3,5,29,[32][33][34]. This has also been confirmed by our modelling analyses and model simulations, which demonstrated that the majority of patients on HDF had a zero probability of achieving the efficacy reference value throughout the entire HDF session.…”