Date: June 9th, 2020

Guest Skeptic: Dr. Chris Bond is an Emergency Medicine Physician and Assistant Professor at the University of Calgary. He is also an avid FOAM supporter/producer through various online outlets including TheSGEM.

Reference: Westafer et al. Provider Perspectives on the Use of Evidence-based Risk Stratification Tools in the Evaluation of Pulmonary Embolism: A Qualitative Study. AEM June 2020.

Case: A 63-year-old female presents to the emergency department (ED) with chest pain for the past eight hours. It is pleuritic, worse with certain movements and associated with some shortness of breath. Her vital signs are within normal limits and oxygen saturation is 95% on room air. An ECG, chest x-ray and troponin are all within normal limits and she has no calf swelling or tenderness. She does have a previous history of DVT/PE 12 years ago after returning from a transatlantic flight. She has also been doing more work around the house and lifting the past few weeks because of COVID and has some mild chest wall tenderness on palpation. The remainder of her Wells’ criteria are unremarkable. How do you proceed in evaluating this patient for pulmonary embolism (PE)?

Background: Pulmonary embolism is a common ED diagnosis with an estimated 1-2% of all patients presenting to United States EDs undergoing CT for suspected PE (1). However, less than 10% of these scans show PE (2-4). We have covered the topic of PE frequently on the SGEM.

* SGEM#51: Home (Discharging Patients with Acute Pulmonary Emboli Home from the Emergency Department)

* SGEM#118: I Hope you Had a Negative D-dimer (ADJUST PE Study)

* SGEM#126: Take me to the Rivaroxaban – Outpatient treatment of VTE

* SGEM#163: Shuffle off to Buffalo to Talk Thrombolysis for Acute Pulmonary Embolism

* SGEM#219: Shout, Shout, PERC Rule Them Out

* SGEM#277: In the Pregnant YEARS – Diagnosing Pulmonary Embolism

* SGEM#282: It’s All ‘bout that Bayes, ‘Bout that Bayes- No Trouble – In Diagnosing Pulmonary Embolism

There are multiple validated risk stratification tools to evaluate for PE and reduce inappropriate testing, including the Pulmonary Embolism Rule Out Criteria (PERC), Wells’score, YEARS algorithm and D-Dimer testing (5-7). There have also been more recent adjustments to D-Dimer threshold based on clinical probability as calculated by a trichotomized Wells score (8).

Unfortunately, clinician uptake of these validated tools has been incomplete, with some ED studies finding 25% of patients who warranted no laboratory or imaging studies still received testing (4, 9-12.) Low-value testing increases costs, ED length of stay and subjects patients to unnecessary ionizing radiation and risk of anaphylaxis from intravenous contrast dye (13-14).  Moreover,