Can non-physician advanced retrieval practitioners (ARP) acquire and interpret diagnostic views of the lungs with sufficient quality to aid in the diagnosis of pneumothorax in the pre-hospital and retrieval environment?
BACKGROUND
As an adjunct to physical examination, ultrasound is a potentially attractive option for diagnosing pneumothoraces in the pre-hospital and retrieval environment - and could confer a benefit to patient safety. However, the published evidence supporting non-physicians use of ultrasound in this setting is limited.


AIM
We aimed to establish if Advanced Retrieval Practitioners (non-physicians) could acquire ultrasound views of the lungs and interpret them with sufficient quality to diagnose pneumothorax in the pre-hospital and retrieval environment when compared to expert review.


METHOD
The study consisted of an observational trial from April 2017 to April 2018. Twelve (12) patients bilateral lung ultrasound images (24 images) were randomly selected from 87 patients assessed using Point of Care Ultrasound (POCUS) by three Advanced Retrieval Practitioners in the Pre-hospital and Retrieval environment. Two expert reviewers' evaluated these images to determine ARPs ability to acquire diagnostic quality images and interpret them correctly. CXR results of patients in whom lung ultrasound was undertaken were recorded as the reference standard investigation.


RESULTS
Within the 22 images considered adequate by the Advanced Retrieval Practitioners, 19 (86.4%, one-tailed McNemar test p = 0.125) were considered adequate on expert review. Of the 19 images mutually considered as adequate, both the Advanced Retrieval Practitioners and the reviewers identified two pneumothoraces which were subsequently confirmed on chest x-ray (Sensitivity 100% and Specificity 100% in technically adequate images). One pneumothorax was detected on CXR in a patient with inadequate ultrasound images. Advanced Retrieval Practitioners were therefore able to both obtain adequate images and correctly diagnose pneumothorax in the pre-hospital environment with 66.6% sensitivity (95%CI 66.6-100%) and 100% specificity (95%CI 81.0-100%) compared to expert review.


CONCLUSION
Advanced Retrieval Practitioners (non-physicians) can obtain diagnostic views of the lungs of sufficient quality to diagnose the presence, or particularly the absence, of pneumothorax in the pre-hospital and retrieval environment. Although Advanced Retrieval Practitioners were less accurate than the expert reviewers at interpreting the quality of the ultrasound images, the result was not statistically significant, despite the ARPs possibly having been at a methodological disadvantage.
['Ronaldson|James|J|http://orcid.org/0000-0003-1623-2132', 'Moultrie|Christopher E J|CEJ|', 'Corfield|Alasdair R|AR|', 'McElhinney|Evelyn|E|']
D000328:Adult D004632:Emergency Medical Services D005260:Female D006801:Humans D008168:Lung D008297:Male D008875:Middle Aged D010820:Physicians D011030:Pneumothorax D014463:Ultrasonography
Pneumothorax Diagnostic imaging Emergency medical services