Anti-bleeding activity

Standards and the recommended therapeutic dose. The antithrombotic potency and potential bleeding effects of one product cannot be extrapolated to another on the basis of weights in milligrams of anti-Xa or anti-IIa activities [34]. 

In all these trials, enoxaparin was administered at the dose of I mg/kg SC every 12 hours, in order to achieve therapeutic anti-Xa levels, This is of importance as it has been demonstrated that low anti-Xa activity (<0.5 lU/mL) was an independent predictor of poor outcome among ACS patients conversely, anti-Xa activity, within the target range of 0.5 to 1.2lU/mL, is not related to bleeding events (23), Among patients with impaired creatinine clearance (chronic kidney disease in elderly patients), the therapeutic range is achieved safely by reducing enoxaparin dose (24),... 

The recommendation for UFH is based on documented efficacy in many older mid-sized trials. Meta-analyses showed a clear reduction in Ml and death, but at the cost of an increase in major bleeding rates (35,36). The advantages of LMWH over unfractionated heparin include a better bioavailability, a stronger and longer anti-Xa activity, less platelet activation, and no need for monitoring. A major drawback of standard heparin therapy is the potential risk of heparin-induced thrombocytopenia, which is considerably reduced with LMWH (37). 

Indometacin should probably not be used postopera-tively in patients with an increased risk of bleeding (SEDA-8, 103), because of its anti-platelet activity. 

In a randomised, crossover study in healthy subjects, there were no important alterations in coagulation tests and plasma anti-Xa activity when danaparoid (3250 anti-Xa units intravenous bolus followed by 750 units subcutaneously twice daily for 8 days) was given with aspirin 500 mg, 14 and 2 hours before the intravenous danaparoid. Similarly, danaparoid did not alter the effects of aspirin on platelet function, but the prolongation in bleeding time tended to be longer after the combination. ... 

Compared to heparin, the sulfated chitosan has been shown to possess high anticoagulant potency. Unlike heparin, sulfated chitosan does not show anti-platelet activity, which causes excessive bleeding in patients (Nishimara et al. 1998). 

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