Shear Wave Elastography of Intercostal Muscles for the Non-invasive Assessment of the Work of BreathinG

NCT07371754 | Not Yet Recruiting

• 1 other identifier: 2025-A01528-41
• Study Type: observational
• Target: 20
• Locations: 0 countries
• Sites: N/A

Brief Summary

Quantifying respiratory effort is a key step in physiological and clinical research on exercise tolerance, mechanisms of fatigability, and ventilatory impairment. To date, reliable assessment relies on an invasive method: esophageal pressure (Pes) measurement using a balloon catheter inserted into the esophagus. Although Pes provides an indirect estimate of pleural and intrathoracic pressure, it is uncomfortable for patients, requires dedicated equipment, and may limit study participation. In critically ill patients, a noninvasive approach to quantify respiratory effort would have major clinical and scientific value. In acute respiratory distress, accurately tracking the intensity and evolution of respiratory effort could support earlier therapeutic decision-making. Shear Wave Elastography (SWE) is an ultrasound technology enabling very high acquisition rates and estimating tissue stiffness from shear-wave propagation induced by an acoustic impulse. Because muscle stiffness is strongly related to force produced during contraction, we hypothesize that intercostal muscle stiffness measured by SWE correlates with respiratory work and increases with rising inspiratory load.

Conditions

COPD; Healthy Adult

Keywords

Shear wave elastography; Intercostal muscles; work of breathing

Outcome Measures

Primary Outcomes (1)

• Correlation between intercostal muscle stiffness (SWE) and respiratory effort (esophageal pressure-time product)

  Intercostal muscle stiffness (kPa) measured by shear wave elastography is correlated with respiratory effort quantified by the esophageal pressure-time product (PTPes; cmH2O·s/min) across the standardized inspiratory loading protocol (within each cohort).

  During a single study visit (≈45 minutes), at rest and at each standardized inspiratory load level

Secondary Outcomes (1)

• Within-subject change in intercostal muscle stiffness (SWE) across inspiratory load levels

  Single study visit: during the inspiratory loading protocol (no resistance, then 25%, 50%, and 75% of maximal inspiratory pressure [PiMax])

Study Arms (2)

Healthy adults

Participant without respiratory, muscle or thoracic abnormalities

Diagnostic Test: Intercostal muscle shear wave elastography (SWE) during standardized inspiratory loading

COPD group

Patients with COPD

Diagnostic Test: Intercostal muscle shear wave elastography (SWE) during standardized inspiratory loading

Interventions

Intercostal muscle shear wave elastography (SWE) during standardized inspiratory loading DIAGNOSTIC_TEST

Ultrasound shear wave elastography (SWE) is performed to quantify intercostal muscle stiffness at rest and during standardized inspiratory loading/controlled breathing. SWE acquisitions are synchronized with physiological reference recordings (e.g., esophageal pressure and/or diaphragm EMG when available) to estimate and track respiratory effort/work noninvasively.

Also known as: Ultrasound shear wave elastography of intercostal muscles

COPD group; Healthy adults

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adults (≥18 years) will be enrolled in two cohorts: (1) healthy adult volunteers and (2) adult patients with chronic obstructive pulmonary disease (COPD), stage 3-4. A total of 20 participants will be recruited (10 COPD patients and 10 healthy volunteers). Each participant will complete a single study visit (\~45 minutes) involving standardized breathing/inspiratory loading while intercostal muscle ultrasound shear wave elastography is recorded, with concurrent physiological reference measurements to quantify respiratory effort.

You may qualify if:

• Adult patient with chronic obstructive pulmonary disease (COPD), stage 3-4.
• Healthy adult volunteer.

You may not qualify if:

• Refusal to participate or withdrawal of consent.
• Age \< 18 years.
• BMI \> 35 kg/m².
• Pregnancy or breastfeeding.
• Inability to understand instructions or cooperate (cognitive impairment, language barrier).
• Neurological condition affecting breathing (e.g., recent stroke, ALS, myopathy).
• Thoracic condition limiting access to the intercostal muscles (e.g., major chest wall deformity, surgical scar).
• Recent thoracic or abdominal surgery (\< 3 months).
• Known esophageal disease (stricture, achalasia, severe esophagitis, diverticulum, history of perforation).
• ENT or tracheal abnormality preventing probe insertion (e.g., tumor, malformation, tracheostomy).
• Swallowing disorders or risk of aspiration.
• Recent exacerbation (\< 6 weeks).
• Oxygen therapy \> 2 L/min during exertion.
• Hemodynamic instability.
• Not affiliated with a social security scheme.

Sponsors & Collaborators

• Groupe Hospitalier du Havre: lead

MeSH Terms

Conditions

Pulmonary Disease, Chronic Obstructive

Condition Hierarchy (Ancestors)

Lung Diseases, Obstructive; Lung Diseases; Respiratory Tract Diseases; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Clément Medrinal

CONTACT

+33664615110; medrinal.clement.mk@gmail.com

Angélique Picard

CONTACT

Angelique.picard@ch-havre.fr

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Day
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 19, 2026
• First Posted: January 28, 2026
• Study Start: March 1, 2026
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): March 1, 2027
• Last Updated: January 28, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will share