Prospective evaluation of real-time use of the pulmonary embolism rule-out criteria in an academic emergency department.

OBJECTIVES: The pulmonary embolism rule-out criteria (PERC rule) is a nine-component decision rule derived to exclude pulmonary embolism (PE) without the use of formal diagnostic testing (D-dimer, computed tomography pulmonary angiography, ventilation-perfusion lung scanning, or venous ultrasonography) when all nine components are negative ("PERC negative"). This study examined whether clinicians who document PERC negative also document results of all nine components of the PERC rule. METHODS: This was a pilot study at a single-center, urban teaching emergency department (ED) with a residency program in emergency medicine. Patients were over 17 years of age with at least one of nine predefined chief complaints. Clinicians were asked three questions regarding suspicion for PE, intent to use the PERC rule, and the result. Charts were independently reviewed by two authors for fidelity of the nine PERC components. Patients were followed for PE outcome at 14 days. RESULTS: The study examined 526 patients cared for by 82 clinicians, who indicated suspicion for PE in 183 of 526 (35%) and intent to use the PERC rule in 115 of 526 (22%) cases, of whom 65 of 115 were documented as PERC negative. No formal test for PE was ordered in 49 of 65 (75%), and 46 of 49 had incomplete documentation to support PERC negative. The most common deficiency was omission of two risk factors for PE in the rule (prior venous thromboembolism or recent surgery). Six patients had PE diagnosed within 14 days, but none of these had been deemed PERC negative. CONCLUSIONS: Clinicians seldom document all nine data elements of the PERC rule in patients they deem PERC negative. These data suggest the need for paper or electronic aids to support use of the PERC rule.