The precursor of low molecular weight heparin is heparin, which is extracted from pig intestines. Heparin is a class of substances. Through cracking, enoxaparin, natroparin, dapparin and domestic low molecular weight heparin were obtained (the cracking method of Xexai is the manufacturing process cannot be imitated).

　　Different molecular weights and different ratios of anti-Xa and anti-IIA were obtained due to different cracking methods (the maximum Kx ratio was 4:1), leading to different anticoagulant effects. So domestic by ion division (not rigorous). Note: Low molecular weight heparin is a biological preparation, the imitation of biological preparation is different from the traditional sense of imitation.

　　The consensus of the Council of the European Union, the Food and Drug Administration of the United States, the American and European Society of Cardiology and other authoritative bodies is that different biologic products are not interchangeable. This suggests that when selecting drugs for clinical use, it should be kept in mind that generic products cannot be assumed to have the same pharmacological activity, efficacy and safety simply because they claim to have the same molecular weight, anti-factor Xa or anti-factor Ⅱ A activity, and/or anti-Xa/anti-matrix A ratio as enoxaparin.

　　Low molecular weight heparin sodium has a lasting antithrombotic effect and is a new drug for the prevention and treatment of thromboembolic diseases.

　　Low molecular weight heparin sodium usage: subcutaneous injection and intravenous injection.

　　Dosage of low molecular weight heparin sodium: dose unit calculated by anti-Xa factor activity unit (anti-XAIU); hemodialysis and hemoperfusion:

　　Single dose: for conventional treatment, 70 to 80 anti-xaiu/kg body weight.

　　Continuous dose: for the first acute patient, the dose was measured at 30 to 40 anti-xAIU/kg body weight before the initial dose, and then 10 to 15 anti-xAIU/kg body weight per hour.

　　For critically ill patients at risk of bleeding, the weight should be measured at 10 to 15 anti-xAIU/kg before starting and then at 5 anti-xAIU/kg per hour.

　　For special cases (e.g. >60 kg, patient weight loss/gain or blood status change) the dose should be tailored as needed.