Assessment of the pulmonary embolism rule-out criteria rule for evaluation of suspected pulmonary embolism in the emergency department
Received 5 March 2007; received in revised form 16 April 2007; accepted 20 April 2007.
Abstract
Background
Overuse of resources when evaluating pulmonary embolism (PE) is a concern if the D-dimer assay is improperly used in the evaluation of emergency department patients with suspected PE. The pulmonary embolism rule-out criteria (PERC) rule was derived to prevent unnecessary diagnostic testing in this patient population. The objective of this study was to assess the PERC rule's performance in an external population.
Methods
This was a secondary analysis of a prospectively collected database comparing PERC rule variables to diagnosis of PE in consecutive patients with suspicion for PE. Bivariate analysis on individual variables and the overall accuracy of the PERC rule were performed.
Results
Patients on 120 randomly assigned shifts were enrolled with a PE prevalence of 12%. The sensitivity, specificity, positive predictive, and negative predictive values of the PERC rule were 100% (95% confidence interval [CI], 79%-100%), 16% (95% CI, 10%-24%), 14% (95% CI, 8%-14%), and 100% (95% CI, 80%-100%), respectively, for the total patient population, and 100% (95% CI, 25%-100%), 33% (95% CI, 12%-35%), 2% (95% CI, 0%-11%), and 100% (95% CI, 75%-100%), respectively, for the low pretest probability population. Bivariate analysis showed unilateral leg swelling, recent surgery, and a history of venous thromboembolic event to be predictive of the diagnosis of PE.
Conclusions
The PERC rule may identify a cohort of patients with suspected PE for whom diagnostic testing beyond history and physical examination is not indicated.
aDepartment of Emergency Medicine, Denver Health Medical Center, Denver, CO 80204, USA
bDepartment of Emergency Medicine, Kaiser Permanente/Exempla St Joseph Hospital, Denver, CO 80218, USA
cDivision of Emergency Medicine, University of Colorado Health Sciences Center, Denver, CO 80262, USA
dDepartment of Preventive Medicine and Biometrics, University of Colorado Health Sciences Center, Denver, CO 80262, USA
Corresponding author. Department of Emergency Medicine, Denver Health Medical Center, Mail Code 0108, Denver, CO 80204, USA. Tel.: +1 303 436 8842; fax: +1 303 436 7541.
ABSTRACT