Principles of Microvascular Surgery.

Antithrombotic therapy
Aspirin
• Administered in low doses - 0.1 mM (325mg - PO).
• Inhibits initial platelet aggregation at the
anastomotic site.
• Inhibits cyclooxygenase - blockage of
thromboxane A2.
• Even at low doses - some inhibition of the release
of prostacyclin (a potent vasodilator and platelet
inhibitor).
Antithrombotic therapy
• Polysaccharide, molecular weights of: 40,000 or
70,000.
• Volume expander.
• Antiplatelet.
• Antifibrin.
» Explanations:
Dextran
• raising of negative electrical charge on platelets.
• Inactivation of von Willebrand factor.
• Rothkopf, PRS 93 - patency of 85% in the dextran
group and 48% in controls.
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