Complications of cutaneous surgery in patients taking clopidogrel- containing anticoagulation

Background: Most anticoagulants are not associated with increased risk of severe complications during cutaneous surgery, but no data exist on clopidogrel. Objective: We sought to determine frequency and severity of perioperative complications in patients taking clopidogrel-containing anticoagulation. Methods: This was a retrospective review of medical records of patients undergoing Mohs micrographic surgery at Mayo Clinic, Rochester, MN, while taking clopidogrel-containing anticoagulation between 2004 and 2008, compared with control subjects taking aspirin monotherapy or no anticoagulants. Results: In all, 220 patients taking clopidogrel-containing anticoagulation underwent 363 surgical procedures on 268 occasions. Severe complications occurred in 11 of 363 surgical sites in 10 cases. Clopidogrel-containing anticoagulation was 28 times more likely than no anticoagulation and 6 times more likely than aspirin monotherapy to result in severe complications after Mohs procedures (P <.001 and P =.022, respectively). Severe complications were 8 times more likely after Mohs procedures in patients taking both clopidogrel and aspirin than in control subjects taking aspirin monotherapy (P =.009). No statistically significant difference was found between patients taking clopidogrel monotherapy and control subjects not taking anticoagulants (P =.15). Patients experiencing severe complications were more likely to have larger postoperative surgical sites (P <.001). No thrombotic complications were encountered with discontinuation of clopidogrel-containing anticoagulation; a postoperative thrombotic complication occurred in one patient whose clopidogrel-containing anticoagulation regimen was modified. Limitations: Retrospective nature of study, possible recall bias as a result of telephone contact, and small number of severe complications were limitations, which reduced study power. Conclusion: Cutaneous surgery in patients taking clopidogrel-containing anticoagulation is associated with an increased risk of nonlife-threatening severe complications.