This audit aims to determine the appropriateness of Computed Tomography Pulmonary Angiogram (CTPA) requests at a single-site emergency department (ED) in a regional hospital, using the Queensland Health (QH) suspected Pulmonary Embolism (PE) diagnostic pathway as the standard of reference. We aim to demonstrate that use of D-dimer testing in accordance with this pathway could potentially reduce the rate of CTPA performance with a resultant reduction in ionising radiation exposure, potential contrast reactions, overdiagnosis of clinically inconsequential PEs1 and expense to the hospital, as well...

The primary goal of diagnostic testing in suspected PE is to identify patients with a high risk of deterioration or clot progression necessitating treatment with anticoagulation2. Due to its protean presentation, this presents a common clinical challenge for which the evidence-base has changed rapidly over the last ten years. A significantly lower diagnostic yield of CTPAs in recent decades suggests an issue of overutilisation in emergency departments3,4. The QH suspected PE diagnostic pathway5 recommends the use of the Wells score, a validated clinical decision tool...

Data was collected on a total sample of 406 CTPAs, 386 of these were included. 11 were excluded as the order request was not made by an emergency clinician and 9 excluded due to known pregnancy. Of the included 386 studies, 43 studies were positive for PE, giving a positivity rate of 11.1%. 377 patients had a retrospective Wells score between 0 to 6, placing them in the low to moderate risk group for PE. Only 30.5% (115) of these patients received D-dimer testing. 188...

The positivity rate of 11.1% is lower than the reported yield rates at other Australian hospitals and significantly less than the Royal College of Radiologists recommended rate of 15.4-37.4%. The RESPECT-ED study reported an average positive rate of 14.6% among 15 Australian emergency departments18 and the Canberra Hospital and Health Service reported 16.2%5. This suggests that appropriate use of D-dimer testing in accordance with the QH diagnostic pathway has a large potential to reduce CTPA utilisation. Only 31.4% of patients in the low to moderate...

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