Gillian Mary Murphy MD, BMedSc, Presenter: Nothing to Disclose

Ian Martin Brennan MBBCh, BMedSc, Abstract Co-Author: Nothing to Disclose

Aine Quinn MSC, Abstract Co-Author: Nothing to Disclose

Mary Theresa Keogan MD, Abstract Co-Author: Nothing to Disclose

With the introduction of computerised ordering systems for radiology, an opportunity has developed to introduce interactive decision systems at the time of ordering a scan. This study centres on the development of an interactive computerised ordering system for CT Pulmonary Angiograms (CTPA). The aim is to identify patients at high risk for pulmonary embolism (PE), improve the positive yield of CTPA’s and reduce inappropriate radiation exposure.  

A retrospective study was initially performed during a 12-month period in 2008. Clinical data was analysed on all patients who underwent a CTPA. An interactive computerised ordering system ‘CTPA Advisor’(CERNER) was developed and incorporated into the Electronic Patient Record (EPR) and Picture Archive and Communications System (PACS). The Advisor requires ordering clinicians to input relevant patient clinical details when ordering CTPA. The Advisor stratifies patients into high or low risk of having a PE based on Wells Criteria and advises clinicians if they need to order D-dimers and whether to proceed with ordering the test. A further prospective audit was carried out over 12 months in 2009 to assess the impact of the Advisor on the number of CTPA studies performed and positive yield.

The initial retrospective audit revealed that 659 patients underwent a CTPA. Overall 70/659(10.6%) were positive for PE. 37/37(100%) patients with normal D-dimers had a negative CTPA. The audit revealed that clinicians did not apply recommended Wells criteria thus, many patients underwent unnecessary CTPA’s and radiation exposure. Following the introduction of the Advisor, which incorporated Wells criteria and D-dimers, 835 CTPA studies were ordered, 289/835(35%) were subsequently cancelled and 546/835(65%) were completed. Of those completed, 92/546(17%) were positive which was a significant increase (p=0.01) and 454/546(83%) were negative.

Following the introduction of the CTPA Advisor, recommended ordering guidelines were incorporated, patients at high risk for PE were identified, the positive rate of PE increased and inappropriate radiation exposure was reduced indicating the success of this interactive computerised ordering system.   

This pilot study highlights the opportunity to incorporate decision support tools at the point of order entry in order to build a clinically intelligent system with our PACS/EPR environment.

Murphy, G, Brennan, I, Quinn, A, Keogan, M, Development of an Interactive Computerised Decision-based Ordering System for CTPA Scans for Pulmonary Embolism.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9014408.html