Prospective Comparison of Indirect CT Venography Versus Venous Sonography in ICU Patients

Abstract

OBJECTIVE: The purpose of our study was to prospectively compare indirect CT venography (CTV) and duplex venous sonography in the evaluation of acute deep venous thrombosis (DVT) in ICU patients with suspected pulmonary embolism. SUBJECTS AND METHODS: All ICU patients undergoing CT pulmonary angiography in the evaluation of acute pulmonary embolism during a 10-month period were included in the study group. Indirect CTV was performed 3 min after initiation of the contrast bolus and was compared with duplex venous sonography of the lower extremities. Both techniques were compared with a clinical standard when DVT was considered present if a positive result was obtained on sonography or on CTV in the setting of pulmonary embolism. RESULTS: The study group comprised 61 ICU patients. Using the clinical standard, DVT was detected in 10 of 61 patients. The sensitivity and specificity for CTV were 70% and 96%, respectively, and for sonography were 70% and 100%. CONCLUSION: The performance characteristics of CTV and deep venous sonography were similar when compared with a clinical standard. The results support the use of indirect CTV after CT pulmonary angiography as an alternative to sonography in the ICU population.