Evaluation of anticoagulant effect and predicted dose of low molecular weight heparin in hemodialysis by anti-Ⅹa factor activity

Abstract

The purpose of this study was to explore the reasonable dose of low molecular weight heparin (LMWH) in hemodialysis (HD) and the strategy of preventing extracorporeal circuit coagulation (ECC). A retrospective case-control study included patients who used LMWH for anticoagulation during maintenance hemodialysis (MHD) in the Hemodialysis Center of Beijing Hospital from December 2020 to January 2021. Basic data such as weight, height, basic kidney disease, dialysis age and anti-Ⅹa factor activity before, during and after dialysis were collected. A total of 46 patients were enrolled in this study, including 5 patients in coagulation group (10.9%) and 41 patients in non-coagulation group (89.1%). The anti-Ⅹa factor activity reached its peak at 0.5 h after the start of HD. The level of anti-Ⅹa factor was incorporated into the receiver operating characteristic curve (ROC curve). The results showed that the area under the ROC curve (AUC) was 0.802 (95% confidence interval: 0.651-0.54, P=0.029), and the cutoff was 0.31 IU/ml (sensitivity 1, specificity 0.683). It is suggested that the body surface area should be used as the basis to estimate the anticoagulant dose of LMWH in HD, and the activity of HD 4 h anti-Ⅹa factor ≤0.31 IU/ml, which is of diagnostic value for ECC. In addition, the results of binary logistic regression analysis showed that dialysis age was an independent risk factor for ECC (OR value 1.319, 95%CI 1.052-1.654, P=0.017). In summary, this study reveals that dialysis age may be a risk factor for ECC and that the activity of HD 4 h anti-Ⅹa factor ≤0.31 IU/ml can be used as a potential diagnostic cut-off point for ECC in HD patients, which provides a scientific basis for monitoring strategies to prevent blood coagulation in HD filters.