Most anticoagulants are not associated with increased risk of severe complications during cutaneous surgery, but no data exist on clopidogrel.

We sought to determine frequency and severity of perioperative complications in patients taking clopidogrel-containing anticoagulation.

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.

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.

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.

Cutaneous surgery in patients taking clopidogrel-containing anticoagulation is associated with an increased risk of nonlife-threatening severe complications.