Paramedic-performed lung ultrasound deemed presently unfeasible

Patients experiencing respiratory distress are not well served by lung ultrasound administered by paramedics and remotely interpreted by emergency physicians, although this could change if training techniques advance along with telemedicine and ultrasound technologies.

The research behind this conclusion was conducted at the University of Pittsburgh Medical Center and published online Sept. 14 in Prehospital Emergency Care.

Lead author Torben Becker, MD, PhD, and colleagues describe their work training paramedics in the use of a handheld ultrasound device for prehospital lung imaging while also instructing EMS command-center physicians in interpreting such imaging.

The paramedics performed the scans on patients with evident respiratory distress over a three-month period, obtaining anterior and lateral views from both sides of the chest.

They then transmitted the images wirelessly, using a mobile hotspot device, into an online image archive.

The images were interpreted remotely by the emergency physicians and overread by two expert sonographers.

For the study, the researchers assessed agreement between the emergency doctors and the ultrasound experts, as well as between ED diagnosis on chart review and the interpretations by all image readers.

A total of 34 of 78 (43.6 percent) eligible patients had an ultrasound exam completed.

Becker and colleagues defined four a priori hypotheses that would need to be met for the intervention to be considered feasible.

The primary driver of their “not feasible” conclusion was poor agreement between the EMS physicians and the ultrasound experts.

Meanwhile, agreement between EMS physicians and ED diagnosis, as well as between experts and ED diagnosis, was only fair.

Other findings of interest included:

• Image transmission was successful in 25 (73.5 percent) of cases where ultrasound was performed.
• The primary reason for not enrolling an otherwise eligible patient was equipment failure (25.0 percent), followed by patient acuity and patient refusal (18.2 percent each).
• A total of 20 (58.8 percent) completed scans were deemed uninterpretable upon expert review.

“Paramedic-performed prehospital lung ultrasound for patients with respiratory distress and remote interpretation by EMS physicians did not meet the predetermined thresholds to be considered ‘feasible’ in a real-world environment with currently available technologies,” the authors write. “This study identified important barriers to the implementation of prehospital lung ultrasound, which should be addressed in future studies.”