Management of Anticoagulant Therapy in Non-cardiac Surgical Patients in Relation to Their Postoperative Clinical Outcome.

It is estimated that more than 150,000 patients receive anticoagulant treatment in Greece. More than 10% of those will need to undergo surgery annually. Major side effects of all anticoagulants are bleeding or major thromboembolic events perioperatively.

The perioperative treatment of patients receiving long-term anticoagulant therapy is challenging. This is attributed to the continuation of anticoagulants perioperatively, which is associated with an increased bleeding risk while their discontinuation increases the risk of thromboembolic or ischemic events.

Type of surgery and patient's comorbidities (i.e. haematological diseases, renal or hepatic insufficiency, and concomitant use of other anticoagulants) are significant factors associated with perioperative bleeding. According to the 2011 Canadian Cardiovascular Society Guidelines for the Management of Patients with Antiplatelet Disorder, bleeding risk is stratified as following:

• Very high risk: neurosurgery (intracranial or spinal surgery), cardiac surgery (coronary artery bypass grafting or valve replacement).
• Medium risk: intrathoracic, intra-abdominal procedures, orthopaedic, vascular and other selective procedures (prostate or cervical biopsy).
• High Risk: major vascular surgeries (abdominal aortic aneurysm, aortic bypass), major orthopaedic surgery on the lower extremity (total hip / knee), pneumonectomy, enterectomy, placement of permanent pacemaker or internal defibrillator and other selected procedures (kidney biopsy, pericardium puncture, resection of colon polyps).
• Low risk: laparoscopic procedures (cholecystectomy, inguinal hernia repair), dental, dermatological, ophthalmic procedures, coronary angiography, gastroscopy /colonoscopy and other selected procedures (bone marrow or lymph node biopsy, thoracotomy, joint puncture).
• Very low risk: low risk dental procedures (i.e. tooth extraction), skin biopsy or skin cancer excision, cataract surgery.

Surgical thrombotic risk assessment is based on 2014 ESC / ESA Guidelines on non-cardiac surgery. Low risk (<1%) surgeries include superficial surgery, breast procedures etc., medium risk (1-5%) splenectomy, cholecystectomy, etc., and high risk (>5%) are major aortic and other major blood vessel operations, open limb revascularization or amputation or embolectomy, gastric surgery, hepatectomy, etc.