Venous protocols, techniques, and interpretations of the upper and lower extremities.

Deep venous thrombosis and pulmonary embolism are common problems and frequently included in the differential diagnosis of patients presenting to the emergency department and in the acute care setting. Clinical signs and symptoms of these entities are nonspecific and it is important to perform objective testing to confirm the diagnosis and initiate proper therapy. Compression ultrasonography is the diagnostic procedure of choice for the investigation of patients with suspected deep venous thrombosis. This article reviews the clinical indications, diagnostic techniques, and interpretation of compression ultrasound to assess deep venous thrombosis in the upper and lower extremities and to evaluate the role of compression ultrasonography in the assessment of patients with suspected pulmonary embolism.