If the PERC rule is negative, what does this mean?

If the PERC rule is negative, what does this mean?

• A. PE is ruled out
• B. CT scan is required
• C. D-dimer will be positive
• D. Observation only

Answer: (A)

A negative PERC means all eight criteria are absent, placing the patient in very low pretest probability for pulmonary embolism. In this scenario, the chance of PE is so low that you can safely rule it out without ordering a D-dimer test or CT pulmonary angiography. So, PE is considered ruled out based on the negative PERC result in a patient who meets low-risk criteria. If any PERC criterion is present, you would not rely on PERC alone and would pursue further evaluation as indicated.

A negative PERC means all eight criteria are absent, placing the patient in very low pretest probability for pulmonary embolism. In this scenario, the chance of PE is so low that you can safely rule it out without ordering a D-dimer test or CT pulmonary angiography. So, PE is considered ruled out based on the negative PERC result in a patient who meets low-risk criteria. If any PERC criterion is present, you would not rely on PERC alone and would pursue further evaluation as indicated.