SLR - September 2022 - Steven Shader, DPM
Reference: Moster, M., Bolliger, D. Perioperative Guidelines on Antiplatelet and Anticoagulant Agents: 2022 Update. Curr Anesthesiol Rep 12, 286–296 (2022).Scientific Literature Review
Reviewed By: Steven Shader, DPM
Residency Program: Bethesda Hospital East, Boynton Beach, FL
Podiatric Relevance: Many surgical patients are prescribed antiplatelet or anticoagulant agents for various reasons. The guidelines on preoperative continuation versus cessation are constantly changing. This is an updated review of recent literature to guide the surgeon on when and what antiplatelet and anticoagulant drugs must be stopped prior to surgery and when to restart postoperatively to avoid complications.
Methods: A literature review including the last 5 years of any published preoperative guidelines on managing antiplatelet and anticoagulant drugs in the perioperative course using a search on PubMed and of homepages of societies of anesthesiology.
Results: Vitamin K Antagonists (VKA) coumarins are indirect inhibitors and the only approved therapy in patients with mechanical heart valves. Warfarin is the only VKA used in US. Warfarins half-life is 36 hours. Preoperative Prothrombin time (PT) and internal normalized ratio (INR) can be tested for a patient on Warfarin prior to surgery, with a goal of preoperative INR < 1.5. Perioperative interruption of Warfarin will leave the patient to subtherapeutic anticoagulation for 10 to 15 days, bridging with heparin can be used to shorten this interruption. For patients with one of these high risk factors bridging is recommended including mechanical mitral valves, caged or tilting disc aortic valves, deficiency of Protein C or S , antithrombin, antiphospholipid syndrome, homozygous factor V Leiden or prothrombin gene mutation. If emergent surgery is required Warfarin can be reversed with Vitamin K. Low bleeding risk procedures like arthroscopy can be performed without stopping Warfarin. DOAC (Direct-acting Oral Anticoagulants) like Rivaroxaban factor Xa inhibitor , requires no regular laboratory testing. Idarucizumab and Andexanet Alfa are used to reverse DOAC. Heparin anti-Xa activity test can be used to determine levels of DOACs. Delay elective surgery for 1 year after placement of drug-eluting stents (DES) and 30 days after bare metal stents if need to hold anticoagulants. Proceed with surgery after 3 months if the risk of delaying surgery > the risk of stent thrombosis. Patient on DAPT (Dual Antiplatelet Therapy) that requires urgent surgery should be on DAPT for at least 4 weeks after DES stenting and continue aspirin at least, ideally DAPT perioperatively. If P2y12 receptor inhibitor like Clopidogrel is held perioperatively restart asap postoperatively.
Conclusion: Warfarin is stopped 3 to five days prior to elective surgery and resumed within 24 hours post-operatively. BRIDGE and PERIOP2 study concluded that in low-risk patients bridging did not reduce the risk of thromboembolic events and increased the risk for bleeding. DOACs due to a 7 hour half-life, are stopped 24 hours prior for low bleeding risk procedures and 48 hours for high bleeding risk procedures or if the patient has impaired renal function with low body weight or advanced geriatric age. DOACs require no bridging and are resumed one day postoperatively in a low bleeding risk procedure and 2 days in a high bleeding risk procedure. PAUSE study confirmed this DOAC interruption safe. Aspirin therapy in patients with arthrosclerosis or stents should not be stopped if the surgeon accepts the increased bleeding risk.