PERC Rule (Pulmonary Embolism Rule-out Criteria)
PERC (Kline 2004; prospective validation Kline 2008)When the clinician's gestalt pre-test probability of PE is low, the absence of all eight PERC criteria excludes PE without any D-dimer or imaging.
Also searched as: emergency · decision rule · rule out
Information
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- Please provide: clinician gestalt assessment (low vs not low).
How this tool works
PERC is a rule-out instrument for emergency-department patients already judged low risk by clinician gestalt (validation used a < 15% estimated probability). If any of the eight criteria is present — age 50 or more, heart rate 100 or more, oxygen saturation under 95% on room air, hemoptysis, estrogen use, prior venous thromboembolism, unilateral leg swelling, or recent surgery/trauma requiring hospitalization — the rule is positive and the standard workup continues. If all eight are absent in a low-gestalt patient, PE is considered excluded with a 3-month miss rate around 1% in validation cohorts. PERC must never be applied when gestalt is not low.
References
- Kline JA, et al. J Thromb Haemost 2004;2:1247-1255 (derivation)
- Kline JA, et al. J Thromb Haemost 2008;6:772-780 (validation)
- 2019 ESC Guidelines, acute pulmonary embolism. Eur Heart J 2020;41:543-603
Implemented from the cited published sources. Educational use only; confirm against current guidelines before clinical use.
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