Dalteparin in emergency patients to prevent admission prior to investigation for venous thromboembolism.

A 15-month prospective cohort study of emergency department (ED) patients with suspected venous thromboembolism was conducted to assess the role of low molecular weight heparin (dalteparin) in an emergency setting in suspected venous thromboembolism prior to diagnostic confirmation. Patients were given a therapeutic dose of dalteparin and were discharged home; they then returned the next day for diagnostic testing. All patients were followed for 3 months. Of 128 patients, 44 had positive test results and 84 had negative test results. Four patients required admission for other reasons. Seventeen had continuing symptoms after initial negative testing; 10 returned to the ED and 9 had repeat Doppler ultrasound, all of which remained negative. None of the 84 negative patients were diagnosed with venous thromboembolism subsequent to an initial negative test. There were no serious adverse effects. This study suggests that treatment with low molecular weight heparin pending outpatient investigation for suspected venous thromboembolism in emergency patients is safe and effective. This could lead to substantial cost savings in the management of this problem. Further study is warranted.