Periprocedural Management of Anticoagulation in the Era of Direct Acting Oral Anticoagulants

Abstract

Periprocedural Management of
Anticoagulation with Vitamin K
Antagonists
Patients who receive oral anticoagulation
(AC) for stroke prevention often undergo
surgical procedures. The interruption of oral
AC might result in a thromboembolic event
(TE), especially in patients at higher risk for
TE. To prevent TE, parenteral AC is often
provided during this interruption of oral
AC. This practice is referred to as “bridging
anticoagulation.”
Interruption of oral AC is common, occurring
in up to 30% of patients over a 2 year period
[1]. In the case of vitamin K antagonists (VKA)
the interruption may result in sub-therapeutic
anticoagulation for over 10 days. This is due to
the fact that VKAs achieve their anticoagulant
effect by synthesis of dysfunctional clotting
factors. Because the half- lives of some of these
endogenous factors are long, warfarin is often
stopped for 5 days prior to surgery, to ensure
adequate hemostasis. Because of the long halflives,
when VKA’s are re-started after surgery,
it may take 4-5 days or longer to achieve
therapeutic anticoagulation, usually defined
as an INR >2.0. Traditionally, parenteral AC
with either unfractionated heparin (UFH) or
low molecular weight heparin (LMWH) can
be used in the perioperative period to prevent
a TE.