Which action is most directly used to confirm a suspected lower-extremity venous thrombus?

Which action is most directly used to confirm a suspected lower-extremity venous thrombus?

• A. Measure the diameter of both legs
• B. Obtain lab studies for aPTT, PT, and INR
• C. Anticipate a lower-extremity ultrasound
• D. Place a warm compress on the leg

Answer: (C)

To confirm a suspected lower-extremity venous thrombus, you need imaging that directly visualizes the veins. The most direct and reliable test is a duplex ultrasound of the leg, usually performed as a compression ultrasound. In this study, if the vein fully compresses, it is typically not occluded; if a thrombus is present, the vein fails to compress and Doppler flow patterns show abnormalities. This test is noninvasive, fast, and widely available, and it both confirms the diagnosis and helps locate the clot to guide treatment. Why other options aren’t the confirmation tool: measuring leg diameter isn’t diagnostic for a clot and can be affected by many factors; coagulation labs like aPTT, PT, and INR assess bleeding risk and coagulation status but not the presence of a vein clot; a warm compress may provide comfort but does not diagnose or confirm a DVT.

To confirm a suspected lower-extremity venous thrombus, you need imaging that directly visualizes the veins. The most direct and reliable test is a duplex ultrasound of the leg, usually performed as a compression ultrasound. In this study, if the vein fully compresses, it is typically not occluded; if a thrombus is present, the vein fails to compress and Doppler flow patterns show abnormalities. This test is noninvasive, fast, and widely available, and it both confirms the diagnosis and helps locate the clot to guide treatment.

Why other options aren’t the confirmation tool: measuring leg diameter isn’t diagnostic for a clot and can be affected by many factors; coagulation labs like aPTT, PT, and INR assess bleeding risk and coagulation status but not the presence of a vein clot; a warm compress may provide comfort but does not diagnose or confirm a DVT.