In the assessment pathway for suspected pulmonary embolism, if the PERC rule is positive, which test is typically performed next?

In the assessment pathway for suspected pulmonary embolism, if the PERC rule is positive, which test is typically performed next?

• A. CTA
• B. CXR
• C. D-Dimer
• D. ABG

Answer: (C)

When PERC is positive, you can’t rule out pulmonary embolism based on clinical criteria alone. The next step is to get a D-dimer test. D-dimer is a highly sensitive marker for clot formation, so a negative result can effectively rule out PE in patients with low-to-intermediate pretest probability and may spare you from imaging. If the D-dimer is positive, you then proceed to CT pulmonary angiography to directly visualize the emboli and confirm the diagnosis. Chest X-ray and arterial blood gas don’t diagnose PE and aren’t used to decide the next step in this pathway.

When PERC is positive, you can’t rule out pulmonary embolism based on clinical criteria alone. The next step is to get a D-dimer test. D-dimer is a highly sensitive marker for clot formation, so a negative result can effectively rule out PE in patients with low-to-intermediate pretest probability and may spare you from imaging. If the D-dimer is positive, you then proceed to CT pulmonary angiography to directly visualize the emboli and confirm the diagnosis. Chest X-ray and arterial blood gas don’t diagnose PE and aren’t used to decide the next step in this pathway.