Two-point Compression Ultrasound Technique Risks Missing Isolated Femoral Vein DVTs

BACKGROUND: Deep vein thrombosis (DVT) is a common vascular problem seen in the emergency department (ED) and is commonly identified using ultrasound performed by a vascular lab, the radiology department, or at the point of care. Previous studies have assessed the utility of a two-point vs sequential technique to identify the presence of a thrombus. One particular study reported a concerning rate of isolated femoral vein thrombi that would be missed by a two-point technique. OBJECTIVES: In this study we sought to determine whether the two-point technique misses isolated femoral vein thrombi. METHODS: We conducted a retrospective review of patients who had a new diagnosis of DVT in the ED diagnosed with vascular lab, radiology, or point-of-care ultrasound to assess for the presence and rate of thrombi that would be missed using a two-point scanning technique. RESULTS: We included in our study 356 patients with a diagnosis of new DVT. In our population, 21 (5.9%; 0.95 confidence interval: 3.7%, 8.9%) patients were identified with thrombi isolated to the femoral vein. CONCLUSION: The two-point technique for lower extremity vascular ultrasound is insufficient for ruling out proximal DVTs in ED patients.