A patient presents with an asymmetric leg with trace pitting edema in the affected leg. What is your diagnostic approach to such a patient? What is the role of D-dimer and ultrasound (U/S)? Does this match the 2012 American College of Chest Physicians (ACCP) guidelines?

The first step is to determine your patient’s pretest probability because the recommendations vary based on risk. I can tell you that many ED patients come in with a Wells score of 1-2, which places them in the “moderate pretest probability” category. There are 2 approaches you can take based on the availability of resources at your site (high-sensitivity D-dimer or U/S) and the patient’s comorbidities. Are you referring your patient for a repeat outpatient ultrasound, if warranted?Walk through various patient scenarios to see how the D-Dimer and U/S come into play.

PV Card: Diagnosting DVT – ACCP Evidence Based Guidelines

Adapted from 1
Go to the ALiEM Cards site for more resources.

Thanks to Dr. Jason West (EM resident at Jacobi/Montefiore) for this card idea and deciphering the complex recommendations from the publication.

Bates S, Jaeschke R, Stevens S, et al. Diagnosis of DVT: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2 Suppl):e351S-418S. [PubMed]
Michelle Lin, MD
ALiEM Editor-in-Chief
Professor and Digital Innovation Lab Director
Department of Emergency Medicine
University of California, San Francisco
Michelle Lin, MD


Professor of Emerg Med at UCSF-Zuckerberg San Francisco General. Founder of ALiEM @aliemteam #PostitPearls https://t.co/7v7cgJqNEn
Michelle Lin, MD