Death by Thrombus or exsanguination? A Brief Synopsis of AFP's "Perioperative Antiplatelet Therapy"

A brief synopsis of; Perioperative Antiplatelet Therapy

PIERRE GUY CHASSOT, MD; CARLO MARCUCCI, MD; and ALAIN DELABAYS, MD, University Hospital of Lausanne, Lausanne, Switzerland, DONAT R. SPAHN, MD, University Hospital of Zürich, Zürich, Switzerland

Am Fam Physician. 2010 Dec 15;82(12):1484-1489.

http://www.aafp.org/afp/2010/1215/p1484.html

     The decision whether or not to stop antiplatelet therapy is often an issue for the family physician who is managing a patient who need surgery. It is often debated between the surgeon and the primary care provider. The big question is, "is the patient more likely to throw a clot or bleed to death?"
     Antiplatelet therapy is used after a stroke, MI, ACS, and other thrombogenic situations. It is also important after coronary revascularization and stent placement.  These treatments "act as unstable plaques" until they either heal. Bare metal stents require 6 weeks to 3 months for smooth muscle and endothelium to cover it, respectively  It can take much longer  (up to 3 years) in drug-eluding stents. This is why clopidogrel treatment is given for 6 weeks with bare metal stents and a least a year with drug eluding stents.  It should be used for 2-4 weeks in angioplasty without stents, 3-6 months in an MI, and 6-12 months in an unstable ACS. Aspirin should also be used in these patients. Previous studies have shown that stopping aspirin, even two years later, can cause thrombosis. Thus, aspirin should be a lifelong medication in these patients.
    In general, there is a 20% increase in perioperative bleeding when on aspirin or clopidogrel.  The risk of hemorrhage is up by 50% (which isn't that much considering that the risk of hemorrhage in surgery is small to begin with). Whats interesting is, although it may take longer to get the bleed under control, the surgical mortality is the same. However, stopping antiplatelet therapy is associated with up to a 40% increase in MI and up to an 85% increase in mortality. Thus, the risk of thrombosis is higher than the risk of hemorrhage.
    Aspirin should be used forever in patients who use it for secondary prevention. The only time it may make sense to stop it is in diabetic patients using aspirin for primary prevention. Patients on dual antiplatelet therapy after stent placement should not have elective operations done during this time. If an emergency operation is needed and the clopidogrel must be stopped, the aspirin should be continued.