Keywords:
Arteries / Aorta, Pulmonary vessels, Respiratory system, CT, CT-Angiography, Audit and standards, Screening, Acute, Embolism / Thrombosis
Authors:
K. P. Settipalli, B. Powell
DOI:
10.26044/ranzcr2023/C-301
Results
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 cases were identified as low risk (Wells score less than 2) and 189 were identified as moderate risk (Wells score 2.5 to 6). 11 patients in the low risk group met the PE Rule-out Criteria (PERC) criteria, which precludes the need for any further investigation, however out of the remaining 177, only 41.8% (74 patients) received D-dimer testing. 21.7% (41 patients) of the moderate risk group received D-dimer testing.
This shows poor compliance with the current recommendations that advise a D-dimer level on all moderate risk patients and all low risk patients who do not meet the PERC criteria as per the QH pathway.
Of those who received a D-dimer test in the low to moderate risk group, the ADJUST-PE criteria could have prevented 17 CTPAs.
Out of 84 patients with a Wells score of 4 or less, 64.2% (54) had D-dimer less than 1000 ng per millilitre, and out of 16 patients with a Wells score of 4.5 to 6, 12.5% (2) had D-dimer less than 500 ng per millilitre. These patients could have had PE excluded on D-dimer and Wells score alone, without need for CTPA, with use of PEGeD criteria.
No patients who met ADJUST-PE criteria had a positive PE. However, 3 patients who met the PEGeD criteria of Wells score less than 4 and D-dimer less than 1000 ng per millilitre had a CTPA positive for PE.