Newer Hemostatic Agents Used in the Practice of Dermatologic Surgery
Table 2
Anticoagulant and antiplatelet medications [9–11].
Drug
Pharmacodynamics
Indications and monitoring
Discontinuation
Reversal
Warfarin
Coumarin inhibits the enzyme epoxide reductase, inhibiting the -carboxylation of Vitamin K-dependent clotting factors: II, VII, IX, X, Protein C, and S [11].
Indications: acute/chronic venous thromboembolism, pulmonary embolism, atrial fibrillation, prosthetic heart valves. Monitoring: PT and INR. When combined with aspirin, heparin, herbal supplements, or other acquired coagulopathies, can lead to potentiated increase in PT/INR in the patient. Generally recommend a PT/INR level 1 week prior to surgery (2–3.5 range recommended).
Discontinuation not recommended for dermatologic surgery. If patient is at high risk for bleeding during the procedure, consider delaying the surgery until better hemostatic control is obtained.
Reversal generally not needed. If an emergent situation arises, fresh frozen plasma, prothrombin complex concentrates, or recombinant Factor VIIa can be used. Parenteral Vitamin K administration can also be used, but takes longer for effects to be seen.
Unfractionated Heparin
Binds to antithrombin III which leads to inactivation of thrombin and Factor Xa.
Indications: DVT, pulmonary embolism, acute arterial occlusion, as a bridge in conjunction with Warfarin until Warfarin levels become therapeutic. Monitoring: aPTT. Check aPTT level 1 week prior to surgery as well as a CBC to check for platelet levels.
Discontinuation not recommended for dermatologic surgery.
Reversal generally not needed. If an emergent situation, 1 mg of protamine sulfate for every 100 units of heparin in vivo can be given.
Dabigatran
Direct thrombin inhibitor.
Indications: Atrial fibrillation. Monitoring: Not recommended.
Discontinuation not recommended for dermatologic surgery.
No reversal agent. Control bleeding site, give supportive care.
Aspirin
Irreversibly inhibits the cyclooxygenase enzymes, which decreases the levels of , decreasing platelet aggregation.
Indications: MI, TIA/stroke prevention, CAD, fever, pain, inflammatory diseases (RA), cardiac stent placement. Monitoring: Not recommended, but platelet inhibition can be monitored by bleeding time or PFA-100.
Prophylactic aspirin with no prior history of myocardial infarction or cerebral vascular events should be discontinued 10–14 days prior to procedure due to irreversible effect on platelets and started 1 week postoperatively. ASA used for therapeutic purposes or prophylactically in high risk individuals should be continued.
Reversal generally not needed.
Ticlopidine and Clopidogrel
Thienopyridines that irreversibly inhibit adenosine-diphosphate receptors, decreasing platelet aggregation [12].
Indications: Drug eluding stent, TIA/stroke, MI, PVD. Monitoring: Not recommended. Can be monitored by bleeding time or PFA-100.
Discontinuation not recommended, although Clopidogrel has been shown to lead to greater bleeding complications than other antiplatelet agents [12].
Reversal generally not needed.
Cilostazol
Vasodilator that inhibits cellular phosphodiesterase, decreasing platelet aggregation.
Indications: Commonly used in treatment of peripheral arterial disease for intermittent claudication. Monitoring: Not recommended.
No recommendations have been made regarding discontinuation.
Reversal generally not needed.
Dipyridamole
Vasodilator that inhibits cGMP phosphodiesterase and cellular uptake of adenosine.
Indications: Mostly used in combination with other drugs such as aspirin (Aggrenox) or warfarin after cardiac valve replacement. Monitoring: Not recommended.
No recommendations have been made regarding discontinuation.
