PURPOSE:Rapid, accurate risk stratification is paramount in the management of pulmonary embolism (PE). Identifying patients with a high risk of mortality may facilitate more aggressive interventions. Similarly, determining those at low risk for death may reveal a cohort of patients who are candidates for outpatient therapy. PESI represents a simple and novel risk scoring system for PE. The inter-observer variability of PESI is unclear.
METHODS:Two clinicians reviewed the records of patients diagnosed with acute PE and calculated a PESI score. The diagnosis of PE was based on objective testing (e.g., high probability ventilation perfusion scan, CT scan with PE protocol, magnetic resonance angiography of the pulmonary vasculature, or pulmonary angiogram). The clinicians were blinded to the scoring of the other observer and patient outcomes. Raw PESI scores were converted into risk classes (e.g., I-V). We employed kappa statistics to evaluate the inter-observer variability in both raw PESI scores and final risk class.
RESULTS:The cohort included 129 subjects (mean age 60.0+/-18.4 years, 49.6% female). The majority of patients were diagnosed by CT. The mean PESI scores were 101+/-40 for observer 1 versus 97+/-40 for observer 2. The kappa score was 0.881, p<0.001. There was also good inter-observer agreement with respect to risk class (kappa 0.622, p<0.001). In 87% of cases, the clinicians agreed as to the PESI risk class. In only 9 (7%) instances was there disagreement by more than one risk class strata. When dichotomizing risk classes into low risk (class I-II) vs. higher risk (class III-V), we noted an even higher degree of concurrence (kappa 0.73, p<0.001).
CONCLUSION:PESI has a low level of inter-observer variability. Although there may be some variance with respect to precise PESI scores, this does not significantly alter risk classification.
CLINICAL IMPLICATIONS:The reliability of PESI suggests it may be broadly applied in clinical scenarios and can form the basis for prospective clinical trials for PE management.
DISCLOSURE:Chee Chan, None.