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Word of the Day

Bridging heparin during surgery not supported by evidence

Clinical Question:
Does periprocedural heparin to bridge anticoagulation in patients taking oral anticoagulants improve clinical outcomes?

Bottom Line:
A strategy of bridging anticoagulation using unfractionated or low-molecular-weight heparin (LMWH) is not supported by high-quality evidence. Adequately powered randomized trials that measure patient-oriented outcomes are needed. (LOE = 2a)

Siegal D, Yudin J, Kaatz S, Douketis JD, Lim W, Spyropoulos AC. Periprocedural heparin bridging in patients receiving vitamin K antagonists: systematic review and meta-analysis of bleeding and thromboembolic rates. Circulation 2012:126(13):1630-1639.  [PMID:22912386x]

Study Design:
Meta-analysis (other)

Unknown/not stated

Inpatient (any location)

For a patient using long-term anticoagulation who is undergoing a surgical procedure, there are 3 options: continue anticoagulation (which is slow to reverse in the event of bleeding), stop anticoagulation altogether (which may increase the risk of thromboembolism), or use heparin as a therapeutic bridge that maintains anticoagulation but can be quickly reversed. Which is best? The authors did a careful search to identify studies of periprocedural bridging with heparin, and identified 34 relevant observational studies. There was some heterogeneity; although all included LMWHs, only 36% included unfractionated heparin. The only randomized controlled trial identified by the researchers had a grand total of 13 patients. Most studies discontinued oral anticoagulation 3 or more days prior to surgery, most offered LMWHs and approximately half reinstituted oral anticoagulation within 24 hours of surgery. The time that a LMWH was discontinued prior to surgery varied: from 12 to 23 hours (36%); at least 24 hours (36%); or not specified (27%). Studies were generally of poor quality: most did not blind outcome assessment, and most did not report losses to follow-up. Thromboembolic events were actually more common in bridged than nonbridged patients (0.9% vs 0.6%), primarily due to more arterial thromboembolic events in bridged patients. Major bleeding was also more common in bridged patients (4.2% vs 0.9%), as was overall bleeding (13.1% vs 3.4%) and mortality (0.3% vs 0.1%). Some observational studies reported data for patients who did and did not undergo bridging, and found no difference in thromboembolic events (odds ratio [OR] = 0.8; 95% CI, 0.42 - 1.54), but found a higher risk of major bleeding (OR = 3.6; 1.52 - 8.50). This should be interpreted with caution, since patients may have been selected for bridging because they were at higher risk of thromboembolic complications.


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