Bates, Shannon M et al. “Diagnosis of DVT: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.” Chest vol. 141,2 Suppl (2012): e351S-e418S. doi:10.1378/chest.11-2299
The Idea: Deep vein thrombosis (DVT) is a prevalent condition that results in many patients presenting to outpatient settings with suspicious features. It is vital to identify a DVT because there are fatal complications of missed DVT and risks associated with anticoagulant therapy. This paper aims to create a strategy to rule out DVT when it is absent and rule in DVT when it is present by using a combination of clinical probability assessments and imaging studies to identify the most optimal strategy for DVT diagnosis to improve patient outcomes.
Methods: The executive committee and article panel members formulated topics focusing on a specific clinical question. After the questions were developed, the panel members defined criteria for eligible studies and specified each question's intended population of interest, intervention, and outcomes. Next, a systematic literature search was done through Medline to evaluate the evidence, and the information found was entered into tables that presented the quality of evidence and clinical outcomes, ultimately resulting in the decisions underlying the recommendations.
Recommendation for patients with high pretest probability: Patients with a high pretest probability (wells score >3) of first lower extremity DVT should undergo compression ultrasound of the proximal veins or whole leg ultrasound over no diagnostic imaging and venography. If compression ultrasound or whole leg ultrasound is positive, the patient will be treated for DVT, and no further confirmatory testing is needed. Patients with a negative compression ultrasound should undergo further testing with either a high sensitivity D-dimer, repeat compression ultrasound in 1 week, or whole leg ultrasound at the present time over no further testing. Patients with negative initial compression ultrasound and positive subsequent D-dimer should undergo repeat compression ultrasound in 1 week or whole leg ultrasound at the present time. Patient with negative initial compression ultrasound and repeat negative compression ultrasound after 1 week does not need any further testing. No further testing is necessary for patients with negative serial compression ultrasound, negative single compression ultrasound with a negative highly sensitive D-dimer, or negative whole leg US.
Takeaway: Guidelines for the diagnosis of DVT recommend that clinical assessment of the pretest probability of DVT should guide diagnostic workup instead of all patients undergoing the same diagnostic process. Patients with high pretest probability should initially undergo compression ultrasound of the proximal veins or whole leg ultrasound.
Elen Mussie, MS4