Period of withdrawal of antiplatelet agents prior to surgery

Period of withdrawal of antiplatelet agents prior to surgery

All patients with coronary stents will be on Aspirin and an additional agent which is a P2Y₁₂ inhibitor (Clopidogrel, Prasugrel or Ticagrelor). The antiplatelet therapy is likely to be more aggressive in those on drug eluting stents (DES). More so in those who have been implanted with a DES in the past one year, because the risk of stent thrombosis on withdrawal of antiplatelet agents is higher in that period. The mandatory period is changing with newer generations of drug eluting stents and depending on patient characteristics.

Platelet function recovery takes place at the rate of about 10% per day. But full recovery of function may not be required for adequate hemostasis with platelet aggregation. There is also a chance of rebound prothrombotic state with higher levels of thromboxane A2. Hence perioperative withdrawal of aspirin carries a significant risk of ischemia. There is significant evidence to suggest that aspirin should not be withdrawn prior to most non cardiac surgeries unless the bleeding risk of the surgery is high as in case of neurosurgery and transurethral resection of prostate (TURP). On the other hand, surgeries with low bleeding risk like cataract surgery may not need withdrawal of antiplatelet agents.

Clopidogrel is typically withdrawn 5 days prior to surgery while Prasugrel needs to be withdrawn 7 days prior to surgery. Prasugrel is a third generation thienopyridine with faster onset of action and more irreversible platelet inhibition than clopidogrel.

Ticagrelor also has a more rapid onset of action and more consistent anti platelet action than clopidogrel. Being an antiplatelet agent with reversible action, the offset of action is more predictable. There is almost complete recovery of platelet aggregation at 5 days of withdrawal of ticagrelor therapy. Variation in pattern of withdrawal exist between cases depending on the risk benefit ratio in each situation.