The new oral anticoagulants are approved for a variety of clinical syndromes, including the prevention of stroke in atrial fibrillation, acute coronary syndromes, treatment of venous thromboembolism (VTE), and prevention of venous thrombosis after total joint surgery or hip fracture. Published guidelines have differing recommendations on the safe interval between discontinuation of the anticoagulant and performance of neuraxial procedures and between the interventional procedure and redosing of the drug. While two to three half-life intervals might be acceptable in patients who are at high risk for VTE or stroke, an interval of four to six half-lives between discontinuation of the drug and neuraxial injections is probably safer in most patients at low risk of thrombosis. In those with renal disease, the interval should be based on creatinine clearance. After a neuraxial procedure or removal of an epidural catheter, anticoagulants can be resumed within 24-48 h in most patients, but they can be taken sooner in patients who are at higher risk for VTE or stroke, that is, 24 h minus the time to peak effect of the drug. The new antiplatelet drugs prasugrel and ticagrelor should be stopped 7 or 5 days, respectively, before a neuraxial injection and can be restarted 24 h later. In selected situations, laboratory monitoring of the anticoagulant effect is appropriate, and reversal agents are suggested when there is a need to rapidly restore haemostatic function.
The new direct-acting oral anticoagulants (ACOD) in patients on prolonged treatment require the need to balance the risk of haemorrhage by administering them against the risk of thrombosis on withdrawing them. Recommendations for their management are proposed in the present article: A) Thromboprophylaxis and general anaesthesia: the performing of regional anaesthesia if administered with an ACOD as thromboprophylaxis requires some safety intervals based on their pharmacokinetic parameters; B) Management of ACOD in elective surgery: in patients with normal renal function and a low haemorrhage/thrombosis risk, stop the ACOD two days before the surgery; it the haemorrhage/thrombosis risk is high and/or renal function is impaired, therapy with a low molecular weight heparin is proposed from 5 days prior to the surgery, and C) Management of ACOD in urgent surgery and associated haemorrhage: the systematic prophylactic administration of haemostatics is recommended. In the event of acute bleeding that may place the life of the patient at risk (due to volume or location), the administration of concentrated prothrombin complex, fresh plasma, or factor VIIa, must be assessed, together with general control measures of acute haemorrhage. These recommendations should be considered in the context of the use drugs that do have a specific antidote, where their monitoring by the usual coagulation tests is not routine, and with those in which there is limited experience. We believe they need to be reviewed in the future, depending on further studies and clinical experience obtained.
Novel oral anticoagulants (NOAs) which directly inhibit thrombin (dabigatran) or factor Xa (rivaroxaban and apixaban) have recently been developed. We report the first case of perioperative management of a patient treated with dabigatran requiring haemodialysis before emergency surgery. A 62-yr-old woman visited the emergency department for a left bi-malleolar ankle fracture; she had a past medical history of severe ischaemic cardiomyopathy, alcoholic cirrhosis Child B, and moderate chronic renal insufficiency. The patient was treated with dabigatran for a left ventricular aneurysm with thrombus. Cutaneous manifestation of a voluminous haematoma required emergency surgery. Blood tests revealed dabigatran anticoagulant activity of 123 ng ml(-1) (therapeutic values: 85-200 ng ml(-1)), activated partial thromboplastin time of 63 s, and a prothrombin ratio of 68%, indicating that dabigatran disturbed coagulation. We decided to perform emergency haemodialysis before surgery. After 2 h, the anticoagulant activity of dabigatran was 11 ng ml(-1), allowing surgery. Surgery proceeded without any problems and the postoperative period was unremarkable. This case highlights the difficulties for the anaesthesiologist regarding emergency perioperative management of patients treated with NOAs and confirms the efficacy of haemodialysis in cases of dabigatran treatment. NOAs should be prescribed with caution, especially for patients with renal or hepatic disease, at least as long as no antagonist is available. In cases of deferred operative urgency in haemodynamically stable patients treated with dabigatran, haemodialysis should be considered to reverse dabigatran's anticoagulant effects.