Second, a nearly ubiquitous belief exists that anticoagulation is withheld or reversed for CDT.⁷ In fact, anticoagulation is continued during CDT and can include LMWH.^9,10 Similarly, use of LMWH does not preclude salvage thrombolytic use. The TOPCOAT trial, evaluating tenecteplase for intermediate-risk PE, protocolized the use of LMWH prior to thrombolysis, switching patients started on UFH to a LMWH.¹¹ Most patients hospitalized with PE undergo neither CDT nor thrombolysis and, even if they do, administration of LMWH is not a contraindication. Although we may worry about the potential for decompensation and don’t want to preclude advanced therapies, this fear should not motivate us to choose UFH over a LMWH for most patients.

In addition, a circular pattern of deference of anticoagulant choice exists within the hospital spectrum of care. In the qualitative study, emergency physicians revealed choosing UFH over LMWH not only because this is how they were trained and the inertia of their practice pattern, but also to allow more flexibility to the inpatient team. Hospital medicine clinicians revealed that even if they preferred an alternative to UFH, they were unlikely to change the anticoagulant until preparation for discharge. Hospitalists cited not wanting to “second guess” the emergency physician and the hassle of multiple changes in anticoagulation regimens as reasons they continued UFH use in these cases.⁷

Unfractionated heparin has a role in a select minority of patients with acute PE, largely in patients on vasopressors who may have impaired subcutaneous absorption of LMWH, those who are actively bleeding or are imminently undergoing invasive surgical procedures, and those with severe renal dysfunction in whom renally dosed LMWH or DOACs are contraindicated. However, these exceptions account for a minority of patients hospitalized with PE. It’s time to dispel the myths associated with UFH and embrace alternatives as the default, reserving UFH for a much narrower subset of patients with PE.

Dr. Westafer (@Lwestafer) is an attending physician and research fellow at Baystate Medical Center, clinical instructor at the University of Massachusetts Medical School in Worcester, and co-host of FOAMcast.

References

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