ULTRASONOGRAPHIC SCREENING BEFORE HOSPITAL DISCHARGE FOR DEEP VENOUS THROMBOSIS AFTER ARTHROPLASTY - THE POST-ARTHROPLASTY SCREENING STUDY - A RANDOMIZED, CONTROLLED TRIAL

Background: The clinical significance of asymptomatic deep venous thro mbosis that develops after joint arthroplasty and the value of screeni ng tests to detect thrombi are uncertain. Objectives: To determine ?) the rate of symptomatic deep venous thrombosis or pulmonary embolism o ccurring after hospitalization for joint arthroplasty and 2) the value of screening compression ultrasonography. Design: Double-blind, rando mized, controlled trial. Setting: Tertiary care hospital. Patients: 10 24 patients undergoing elective total hip or knee arthroplasty who rec eived warfarin prophylaxis. Intervention: Patients were randomly assig ned to undergo either bilateral compression ultrasonography or a sham procedure before hospital discharge. Patients with a diagnosis of asym ptomatic deep venous thrombosis were treated after discharge with stan dard anticoagulant therapy; other patients had warfarin therapy discon tinued at discharge. All patients were followed for 90 days. Results: In the screening group, asymptomatic proximal deep venous thrombosis w as detected in 13 of 518 patients (2.5%). Another 4 patients subsequen tly developed symptomatic proximal deep Venous thrombosis, and 1 patie nt treated for asymptomatic deep Venous thrombosis developed major ble eding, for a total outcome event rate of 1.0% (5 of 518 patients). In the placebo group, 3 patients developed symptomatic proximal deep veno us thrombosis and 2 had nonfatal pulmonary embolism, for a total event rate of 1.0% (5 of 506 patients) (difference, 0 percentage points [95 % CI, -1.2 to 1.2 percentage points]). Conclusions: In patients underg oing total hip or knee arthroplasty, the use of warfarin prophylaxis d uring hospitalization results in a very low rate of symptomatic deep v enous thrombosis or pulmonary embolism after hospital discharge. The u se of screening compression ultrasonography at hospital discharge does not seem to be justified in this setting.