Conservative perioperative anticoagulation management in patients with chronic venous thromboembolic disease: a cohort study


Michael J. Kovacs, Division of Hematology, London Health Sciences Centre, 800 Commissioners Rd E, London, Ontario N6A 5W9, Canada.
Tel.: +1 519 685 8500 ext. 52254; fax: +1 519 685 8477.


Summary.  Background:  Guidelines for perioperative warfarin management in patients with venous thromboembolic disease (VTE) are largely based on expert opinion.

Objectives:  To assess the effectiveness and safety of a conservative perioperative anticoagulation strategy in patients with VTE on chronic warfarin therapy. Our center uses a conservative bridging approach for chronic VTE patients consisting of withholding warfarin for 5 days preoperatively, with prophylactic low-molecular-weight heparin (LMWH) post-procedure only if patients are admitted to hospital.

Patients/Methods:  We performed a single-center retrospective cohort study. During the study period (1997–2011) there were 634 procedures in 416 patients that were reviewed for postoperative outcomes at 30 and 90 days.

Results:  Of the 634 procedures, 156 procedures (24.6%) were completed as inpatients. Pre- and post-procedure LMWH bridging was used in 15 (2.4%) and 152 (24.0%) of all procedures, respectively. The 30-day VTE incidence was 0.32% (95% confidence interval [CI] 0.087–1.14), all non-fatal DVTs. The 30-day incidence of major and total bleeding events was 1.26% (95% CI 0.64–2.47) and 3.00% (95% CI 1.93–4.63), respectively. The all-cause mortality rate was 0.32% (95% CI 0.087–1.14) at 30 days; two patients died from arterial thrombosis events.

Conclusions:  A randomized controlled trial is needed to provide definitive conclusions but a conservative bridging approach appears promising.