Low molecular weight heparin sodium binds monovalent sodium ions, and low molecular weight heparin calcium binds divalent calcium ions.
Second, the use is different.
Heparin sodium has the functions of preventing platelet aggregation and destruction, inhibiting fibrinogen from transforming into fibrin monomer, inhibiting the formation of thromboplastin and resisting formed thromboplastin, preventing prothrombin from transforming into thrombin and resisting thrombin. Heparin sodium can delay or prevent blood coagulation in vivo and in vitro.
In heparin calcium, the affinity of heparin for Ca2+ ion is greater than that for Na+ ion. When heparin sodium is used, it will often cause calcium deposition in different tissues, especially in blood vessels and capillaries, especially in high-dose subcutaneous injection. The chelation of calcium destroys the permeability of adjacent capillaries, resulting in petechiae and hematoma.
Heparin calcium can avoid the disorder of electrolyte balance in blood caused by the transformation from sodium salt to calcium salt. It not only has the anticoagulant and antithrombotic functions of heparin sodium, but also is stable, quick-acting, safe and reduces petechiae and hematoma induration. ?
Third, the pharmacokinetics are different.
Low molecular weight heparin sodium reached the plasma peak at 3 hours after subcutaneous injection, and then decreased, but it can still be monitored at 24 hours, with a half-life of about 3.5 hours. The anti-IIA factor activity was lower than the anti-Xa factor activity during the administration period, and the bioavailability of subcutaneous injection was close to 98%.
The pharmacokinetic parameters of low molecular weight heparin calcium were determined by measuring the plasma anti-factor Xa activity, which reached the plasma peak at 3 hours after subcutaneous injection, and then gradually decreased until 24 hours after administration, and the elimination half-life was about 3.5 hours (compared with 2.2 hours after intravenous injection).
References:
Low molecular weight heparin calcium injection-Baidu Encyclopedia
Low molecular weight heparin sodium injection-Baidu encyclopedia