Outpatient VTE is more common than inpatient VTE, especially after a recent hospitalization or surgery.
Some clinicians may believe that inpatient venous thromboembolism (VTE) is far more common than outpatient VTE and that outpatient VTE generally occurs in the absence of recent surgery or hospitalization. These beliefs were challenged in an observational study, in which researchers identified all VTE cases in a mid-sized U.S. city during 3 years.
Of 1897 patients, 74% developed VTE in the outpatient setting. Sixty percent of outpatient cases had undergone surgery or had been hospitalized in the preceding 3 months (usually in the preceding 1 month), and 30% of outpatient cases had no history of recent hospitalization, surgery, infection, malignancy, or VTE. Among individuals with a recent hospitalization, 40% did not receive VTE prophylaxis, and about half had a hospital length of stay of 4 days or less.
Comment: In this observational study, researchers found that outpatient VTE is more common than inpatient VTE and that a large proportion of outpatient VTEs occurred within 1 month of a hospitalization or surgery. Given the short duration of many hospitalizations, the study raises the question of whether VTE prophylaxis should be continued into the outpatient setting for some patients. But to accomplish this cost-effectively, we need data that would enable us to identify a high-risk subgroup at the time of hospital discharge.
Published in Journal Watch General Medicine August 7, 2007
Spencer FA et al. Venous thromboembolism in the outpatient setting. Arch Intern Med 2007 Jul 23; 167:1471-5.