# Paramedics Performed Sonographic Identification of the Conic Ligament—A Prospective Controlled Trial

**Authors:** Johannes Weimer, Christopher David Chrissostomou, Christopher Jonck, Andreas Michael Weimer, Carlotta Ille, Lukas Müller, Liv Annebritt Lorenz, Marie Stäuber, Thomas Vieth, Holger Buggenhagen, Julia Weinmann-Menke, Maximilian Rink, Julian Künzel

PMC · DOI: 10.3390/diagnostics15101296 · Diagnostics · 2025-05-21

## TL;DR

This study shows that paramedics can learn to use ultrasound to identify a key airway landmark as effectively as emergency physicians after proper training.

## Contribution

Demonstrates that paramedics can achieve comparable competence to emergency physicians in POCUS-assisted conic ligament identification after structured training.

## Key findings

- Paramedics showed significant improvement in both subjective and objective competencies after training (p < 0.001).
- Post-training, paramedics performed as well as emergency physicians in identifying the conic ligament using POCUS.
- Paramedics rated the training and materials more favorably than emergency physicians.

## Abstract

Background/Objectives: Acute obstructions of the upper respiratory tract are emergencies that may require a cricothyrotomy as ultima ratio. For this, precise identification of the conic ligament is essential. Point-of-care ultrasound (POCUS) offers a reliable tool for anatomical localization in challenging cases and could be used by a range of emergency medicine workers. This prospective, controlled observational study assesses the development of competencies of paramedics (PMs) in point-of-care ultrasound (POCUS) assisted identification of the conic ligament after structured training, and compares their competence level to emergency physicians (EPs). Methods: PMs and a control group of EPs received an identical structured training program as part of an ultrasound course. It included a 10-min theoretical introduction, a 10-min video, and a 45-min practical session with ultrasound devices. Questionnaires and a practical test assessed both group’s previous experiences, satisfaction with training, and the development of subjective and objective competencies before (T1) and after (T2) the training. Results: A total of 120 participants (N = 92 PMs and N = 28 EPs) participated. A minority had previously performed a cricothyrotomy even in training settings (PMs 17%; EPs 11%), and none had identified the conic ligament using POCUS. The study group’s subjective and objective competencies increased significantly (p < 0.001). At T2, the study group demonstrated comparable subjective (p = 0.22) and objective (p = 0.81) competencies to those of the control group. The study group needed significantly (p < 0.01) less time to perform the DOPS. While both groups were satisfied with the study material (PMs 2.2 ± 1.2 vs. Eps 1.6 ± 1.0; p = 0.02) and the training (PMs 1.8 ± 1.0 vs. EPs 1.4 ± 0.7, p = 0.03), the study group rated both significantly better. Conclusions: After structured training, paramedics successfully identified the conic ligament using POCUS comparably to emergency physicians. Integrating POCUS into paramedic training may improve prehospital airway management and enhance patient safety. Further studies should investigate long-term skill retention and real-life application.

## Full-text entities

- **Diseases:** obstructions of the upper respiratory tract (MESH:D012141)
- **Chemicals:** DOPS (MESH:D015103)
- **Species:** Homo sapiens (human, species) [taxon 9606]

## Full text

_Full body text omitted from this summary view._ Fetch the complete paper as Markdown: https://tomesphere.com/paper/PMC12109798/full.md

## Figures

4 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12109798/full.md

## References

63 references — full list in the complete paper: https://tomesphere.com/paper/PMC12109798/full.md

---
Source: https://tomesphere.com/paper/PMC12109798