PERC rule

Pulmonary Embolism Rule Out (PERC) Criteria

If all are present AND low suspicion for PE, no D-dimer needed:

1. Age <50yr
2. Pulse ox >94% (room air)
3. HR <100
4. No prior PE or DVT
5. No recent surgery or trauma (within prior 4wk)
6. No hemoptysis
7. No estrogen use
8. No unilateral leg swelling

• Use this criteria if confident in excluding PE with negative D-dimer

• Validated on 7527 patients
  • Only 0.9% had PE when PERC negative, no deaths