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Medicine

Clinical Decision Rules for Pulmonary Embolism Risk Stratification

Quick fact

The PERC rule can safely rule out pulmonary embolism in some low-risk patients without any testing at all, but it's only valid for those who are already considered low risk by clinical judgment.

Why this is interesting

You're in the ER with a patient who has chest pain and a racing heart. Could it be a pulmonary embolism? How do you decide whether to order a CT scan that costs time and radiation, or send them home?