Validation of a novel point-of-care ultrasound method to assess diaphragmatic excursion

Diogo Da Conceicao; Anahi Perlas; Laura Giron Arango; Kim Wild; Qixuan Li; Ella Huszti; Jayanta Chowdhury; Vincent Chan

doi:10.1136/rapm-2023-104983

Validation of a novel point-of-care ultrasound method to assess diaphragmatic excursion

Reg Anesth Pain Med. 2023 Nov 8:rapm-2023-104983. doi: 10.1136/rapm-2023-104983. Online ahead of print.

Authors

Diogo Da Conceicao¹, Anahi Perlas², Laura Giron Arango¹, Kim Wild¹, Qixuan Li³, Ella Huszti³, Jayanta Chowdhury¹, Vincent Chan¹

Affiliations

¹ Anesthesia and Pain Management, Toronto Western Hospital - University Health Network, Toronto, Ontario, Canada.
² Anesthesia and Pain Management, Toronto Western Hospital - University Health Network, Toronto, Ontario, Canada anahi.perlas@uhn.ca.
³ Biostatistical Research Unit, University Health Network, Toronto, Ontario, Canada.

PMID: 37940349
DOI: 10.1136/rapm-2023-104983

Abstract

Introduction: Point-of-care ultrasound can assess diaphragmatic function and rule in or rule out paresis of the diaphragm. While this is a useful bedside tool, established methods have significant limitations. This study explores a new method to assess diaphragmatic motion by measuring the excursion of the uppermost point of the zone of apposition (ZOA) at the mid-axillary line using a high-frequency linear ultrasound probe and compares it with two previously established methods: the assessment of the excursion of the dome of the diaphragm (DOD) and the thickening ratio at the ZOA.

Methods: This is a single-centre, prospective comparative study on elective surgical patients with normal diaphragmatic function. Following research ethics board approval and patient written consent, 75 elective surgical patients with normal diaphragmatic function were evaluated preoperatively. Three ultrasound methods were compared: (1) assessment of the excursion of the DOD using a curvilinear probe through an abdominal window; (2) assessment of the thickening fraction of the ZOA; and (3) assessment of the excursion of the ZOA. The last two methods performed with a linear probe on the lateral aspect of the chest.

Results: Seventy-five patients were studied. We found that the evaluation of the excursion of the ZOA was more consistently successful (100% bilaterally) than the evaluation of the excursion of the DOD (98.7% and 34.7% on the right and left sides, respectively). The absolute values of the excursion of the ZOA were greater than and well correlated with the values of the DOD.

Conclusion: Our preliminary data from this exploratory study suggest that the evaluation of the excursion of the ZOA on the lateral aspect of the chest using a linear probe is consistently successful on both right and left sides. Future studies are needed to establish the distribution of normal values and suggest diagnostic criteria for diaphragmatic paresis or paralysis.

Trial registration number: NCT03225508.

Keywords: brachial plexus; diagnostic techniques and procedures; ultrasonography.

Associated data

ClinicalTrials.gov/NCT03225508