What is the role of plethysmography in the workup of venous thromboembolism (VTE)?

Updated: Nov 05, 2020
  • Author: Vera A De Palo, MD, MBA, FCCP; Chief Editor: Vinod K Panchbhavi, MD, FACS, FAOA, FABOS, FAAOS  more...
  • Print

Impedance plethysmography may detect impaired venous emptying of the leg by assessing the volume response to temporary occlusion of the venous system. Emptying is assessed by the rapidity of volume decrease. Slow emptying indicates obstruction.

Impedance plethysmography is a noninvasive method of assessment. Sensitivity and specificity have been reported to be between 92% and 95%. However, it is of limited value when DVT is asymptomatic or distal or when findings are nonocclusive.

Conditions leading to poor forward blood flow, hypotension, or vein compression can be responsible for false-positive results.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!