Reducing CT Pulmonary Angiogram Ordering in the ED

Rationale / Objectives

Brigham & Women's Hospital noted an increase in the ordering of CT Pulmonary Angiography (CTPA) to detect pulmonary emboli. Objectives were to reduce unnecessary diagnostic imaging, increase the yield of positive results from CTPA tests, and improve quality of care by limiting patient exposure to unnecessary radiation.

Project/Program Description & Major Achievements

An electronic clinical decision support tool was developed for ordering CTPA to detect pulmonary emboli. The implementation of evidence-based clinical decision support for CTPA for acute pulmonary embolisms decreased the use of inappropriate CT imaging by 20% and increased the yield by 69%.

Lessons Learned

Computerized decision support may help decrease the number of unnecessary diagnostic imaging orders.

Further Description

Brigham and Women’s Hospital is a 793 bed quaternary care institution with 60,000 annual ED visits. Brigham and Women’s Hospital developed an electronic clinical decision support tool for ordering CT Pulmonary Angiography (CTPA) to detect pulmonary emboli. CTPA is used to diagnose acute pulmonary embolism. The use of CTPA in the emergency department setting increased precipitously in the 5 years leading up to this study. The team aimed to develop a clinical decision support tool to decrease the number of patients undergoing CTPA and increase the yield of positive findings. Patients would benefit from better quality care, fewer unnecessary diagnostic testing, and less exposure to radiation. The research team developed an evidence-based algorithm to assist physicians in the use of CTPA and implemented this decision support tool into the ED radiology computerized physician order entry system. This algorithm used blood levels of D-dimer (elevated, normal, not elevated) along with patient history and level of clinical suspicion for pulmonary embolism (high, intermediate, or low) to guide physicians in ordering a CTPA.

Along with clinical guidance, the clinical decision support tool included a link for additional information and a link to give feedback. In order to rollout the intervention, the team conducted multidisciplinary discussions of the evidence for the clinical decision support tool at two emergency medicine staff meetings, as well as one emergency medicine residency grand rounds presentation. The approach included a multidisciplinary team, physician champions, and an education campaign explaining the evidence behind the recommendations incorporated into the decision support tool. Ordering unnecessary tests negatively affects both patient care and ED function. Firstly, by exposing patients to radiation, the risk of developing other cancers increases. There is also a significant cost associated with ordering unnecessary tests. Lastly, patients waiting for unnecessary tests can cause a significant bottleneck and will negatively impact ED patient flow.

Major Achievements

The implementation evidence-based clinical decision support for CT pulmonary angiography for acute pulmonary embolisms decreased the use of inappropriate CT imaging. A well-planned, targeted clinical decision support tool based on high quality evidence-based guidelines can achieve the objective of improved quality of care and decreased costs. The intervention was also successful because the rollout strategy utilized a multi-factorial approach to changing the hospital culture and the attitudes toward the use of CTPA to rule out pulmonary embolism.

Metric Result Detail (time 1 → time 2)
Use of CTPA in the ED 26/1000 → 21/1000 patients (20.1% decrease)
Yield of CTPA in the ED 5.8% → 9.8% of tests positive (69% increase)

Based on average 1/40 CT summary angiography exams per year, 2% of all ED patients. 1