IS BILATERAL LOWER-EXTREMITY COMPRESSION SONOGRAPHY USEFUL AND COST-EFFECTIVE IN THE EVALUATION OF SUSPECTED PULMONARY-EMBOLISM

OBJECTIVE. Because deep venous thrombosis is clinically linked with pu lmonary embolism and often treated similarly, we sought to assess the usefulness of obtaining bilateral lower extremity compression sonogram s when findings on ventilation-perfusion lung scans indicate a low or indeterminate probability of pulmonary embolism. Demonstration of deep venous thrombosis would provide a rationale for treating both pulmona ry embolism and deep venous thrombosis. MATERIALS AND METHODS. Two hun dred twenty-three consecutive patients with suspected pulmonary emboli sm had ventilation-perfusion lung scans and concurrent bilateral lower extremity compression sonograms; 34 also had pulmonary arteriography. RESULTS. In 75 cases, the results of ventilation-perfusion lung scann ing indicated an indeterminate probability of pulmonary embolism. Evid ence of thrombosis was seen on sonograms in 11 of these 75. In the rem aining 64, 17 underwent pulmonary arteriography and four (24%) had pul monary embolism. Findings on lung scans indicated a low probability of pulmonary embolism in 70 of 223 patients. Evidence of thrombosis was seen on sonograms in 11 of these 70. Five of the remaining 59 underwen t pulmonary arteriography and one (20%) had pulmonary embolism. Accord ing to the 1993 Medicare Fee Schedule, if all 145 patients whose lung scans were nondiagnostic had sonography and only those with normal son ograms had pulmonary arteriography, the professional and hospital char ges would be $359,552. If all 145 had pulmonary arteriography without sonography, the charges would be $395,031. CONCLUSION. If ventilation- perfusion lung scans indicate a low or an indeterminate probability of pulmonary embolism and bilateral lower extremity compression sonograp hy is performed, only those patients with normal sonographic findings would need further study. Thus, 15% (22/145) of patients could be spar ed pulmonary arteriography, and the estimated savings in cost would be 9%.