PADUA score as a predictor for pulmonary embolism: a potential strategy for reducing unnecessary imaging

An objective tool that is easy to integrate with an electronic medical record may help reduce unnecessary imaging for diagnosing a pulmonary embolism (PE). In this study, we assess the PADUA score in stratifying patients based on their risk of a PE. We reviewed charts of patients that underwent a computed tomography pulmonary angiogram (CT-PA) between January 2014 and September 2015 at our institution. Patient demographics including gender, age, race, and variables of the PADUA score were collected. The primary outcome was a positive CT-PA for a PE. Univariate and multivariate analysis was performed to derive predictors for a positive CT-PA. A receiver operator curve was calculated for the PADUA score and an optimal cutoff was calculated. Diagnostic test statistics were performed. Our study included 1067 patients. Of these, 185 (17.3%) had a PE. These patients tended to be older (64.3 SD 15.9 vs. 59.7 years SD 17.4, p < 0.01), have a higher proportion of Black patients (38.9% vs. 31.9%, p = 0.03), have a higher median [IQR] PADUA score (4.0 [3-6] vs. 3.0 [1-4], p < 0.01), and a higher rate of a DVT/PE history (30.3% vs. 5.2%, p < 0.01). Independent predictors included a DVT/PE history (OR: 7.65, 95% CI 4.89-12.0, p < 0.01), limited mobility (OR: 1.47, 95% CI 1.01-2.14, p = 0.046), and age 70 or greater (OR: 1.47, 95% CI 1.03-2.11, p = 0.03). The PADUA score had an AUC of 0.64 (95% CI 0.60-0.69, p = 0.046). The optimal cutoff was 4 and the sensitivity and specificity were 57.3% and 66.8%, respectively. The positive predictive and negative predictive values were 22.6% and 88.2%, respectively. The PADUA is a possible tool to stratify patients prior to performing a CT-PA. By using the score to guide management, we may be able to reduce unnecessary imaging through the implementation of the score in an EMR system. Further prospective research is warranted.