Loading...
Immobilization is a known risk factor for development of venous thromboembolism (VTE), yet the relative effects of different types and durations of immobility are not known. In a prospective noninterventional study, researchers determined the correlation between type of immobility and risk for VTE in 7940 patients who self-presented to 12 emergency departments and were being evaluated for VTE. Categories of immobility were none, generalized (whole-body immobility for >48 hours), limb, travel (immobility for >8 hours because of travel within the previous 7 days), neurological (paralysis), and other.
Overall, 1394 patients (18%) reported immobility, and 545 patients (7%) were diagnosed with VTE (pulmonary embolism in 354, deep venous thrombosis in 72, and PE and DVT in 119). Risk for VTE varied by type of immobility as follows: limb (odds ratio, 2.25), neurological (OR, 2.23), other (OR, 1.97), generalized (OR, 1.76), and travel (OR, 1.19). The increase in risk associated with travel was not statistically significant.
Beam DM et al. Risk of thromboembolism varies, depending on category of immobility in outpatients. Ann Emerg Med 2009 Aug; 54:147.
Comment
In this study, risk for VTE varied by type of immobilization and did not increase significantly from travel. Of note, the type of travel (airplane, train, or automobile) was not recorded and might prove significant. Until further study differentiates the risk for VTE associated with different types of travel, consideration of travel history in the work-up of VTE should not change.