Perioperative interruption of direct oral anticoagulants (DOACs) in patients with venous thromboembolism appears to be both safe and effective, a Canadian study has found.
The retrospective study of 190 patients with a history of largely unprovoked venous thromboembolism (VTE) found low rates of complications or bleeding problems when DOACs were discontinued and reintroduced based on the half-life of the medication and the bleeding risk associated with the procedure.
However, speaking to the limbic, Associate Professor Huyen Tran from the Australian Centre for Blood Diseases at Monash University said most of the patients (76%) were undergoing elective procedures such as colonoscopy, which were low risk for both thrombosis and bleeding.
“Stopping DOACs 60 hours prior to standard, low risk procedures is very conservative but acceptable in this low risk group of patients with VTE, most of whom had their VTE episode more than three months prior,” he said.
He advised that for high-risk procedures for thrombosis, such as joint replacement or anaesthetic time greater than 45min, pharmacological thromboprohylaxis, with or without mechanical methods of haemostasis, should be introduced within 12-24 hours.
It was also prudent to minimise the period of time ‘off’ anticoagulation for patients at high risk of thrombosis including those with recent VTE, antiphospholipid syndrome, cancer-related VTE, AF with high CHADS2/CHADsVASC score or a history of stroke.
“The change in both the thrombosis and bleeding risks are significantly greater after the procedure, and therefore it is during this period that pharmacological thromboprophylaxis (or mechanical if there is contraindications) should be instituted and then escalated to therapeutic as soon as it is haemostatically safe to do so, ideally by 12-24 hours and 72 hours, respectively,” he said.
In the study 13.7% of patients were high risk with a recent VTE within the previous three months.
Most patients (90%) were being treated with rivaroxaban. Discretionary prophylactic doses of low molecular weight heparin or a DOAC in the immediate postoperative period were administered in 41% of patients.
The study found an overall low VTE complication rate of 1.05%, major bleeding rate of 0.53% and clinically relevant but non-major bleeding rate of 3.16% at 30-days.
The discontinuation strategy used by the study authors involved discontinuing the DOAC for a duration three times its half life prior to a standard procedure and recommencing two days post operatively or five times the half life of the DOAC for higher risk procedures and recommencing four days postoperatively.