Use of Point-of-Care Ultrasound by Intensive Care Paramedics to Assess Respiratory Distress in the Out-of-Hospital Environment: A Pilot Study

Abstract

Background

Respiratory distress is a common presentation attended by paramedics. Chest auscultation has been shown to have low accuracy for diagnosing respiratory complaints, and this can lead to inaccurate patient assessment and potentially poor patient outcomes. Conversely, lung ultrasound is a relatively simple exam allowing for rapid differentiation of respiratory complaints with comparable accuracy to more advanced imaging modalities. Evidence suggests that lung ultrasound is easy to learn and apply and could be ideal for assessment of respiratory illness by paramedics.

Objective

This study aimed to explore the utility of out-of-hospital lung ultrasound performed by intensive care paramedics (ICP) for patients with medical causes of respiratory distress, and explore whether the use of lung ultrasound affects the ICP’s clinical impression or management.

Methods

This was a prospective observational pilot study. After a training program, a sample of ICPs working in metropolitan and regional Victoria, Australia used ultrasound to assess adult patients with respiratory distress and/or dyspnea. ICPs used a handheld point-of-care ultrasound device to scan respiratory patients using a modified protocol, and completed a worksheet with their scan findings. The scans were then reviewed by a subject matter expert for quality and agreement.

Results

Ninety-five patients were enrolled over the study period. The average image quality score was 2.68/5, and 56% of scans were of interpretable quality. Interrater agreement (between the ICPs and the subject matter expert) was reported using Cohen’s kappa. Moderate overall agreement (0.44) was shown, with the highest reliability reported in A-profile and B-profile (0.49 and 0.57). In 42% of cases performance of the scan affected paramedic clinical impression and/or management.

Conclusion

ICPs can perform lung ultrasound with moderate accuracy for some respiratory conditions, and the scans may affect clinical impression and management. Future research should focus on enhanced education, expert feedback, and clinical outcomes.

Acknowledgments

The authors would like to thank Butterfly Network for the loan of the ultrasound devices and access to their image review and cloud storage applications. The authors would also like to thank Monash University and Ambulance Victoria for the donation of training space and equipment.

Disclosure Statement

The authors have no conflicts of interest to declare.

Data Availability

Deidentified data are available upon reasonable request from the corresponding author (JD).