Clinical Decision Support for Ordering CTA-PE Studies in the Emergency Department-A Pilot on Feasibility and Clinical Impact in a Tertiary Medical Center

Purpose: To determine the feasibility and impact of Clinical Decision Support for imaging ordering.

Methods: A survey of 231 emergency providers identified Computed tomography angiography (CTA)-Pulmonary embolism (PE) as an overutilized study. We developed an algorithm that combined established risk scores to stratify patients for PE work-up (recommendations: CTA, D-dimer or no further testing); the algorithm was integrated into the Epic Radiology Information Ordering System.

Results: Among 872 studies requested, 479 (55%) received a recommendation to change their order: 6 (1.3%) were cancelled; 13 (2.7%) changed to a D-dimer, and 460 (96%) proceeded with CTA. Of the 853 studies conducted, 8.2% were positive for PE. The algorithm had good discriminatory power with positivity rates of 12.0% (CT), 10.0% (D-dimer), and 2.6% (no further testing). Compliance with the recommendation ranged from 12%-68% (mean 45%) with 10% correlation between compliance and positivity rates.

Conclusion: While the CDS algorithm was accurate, it had only a minimal impact on ordering practices, in part due to heterogeneity in physician adherence.