Impact of Dyspnea, Regional Lung Ventilation, and Diaphragmatic Function During de Novo Acute Respiratory Failure (DY-VI-DI)

Evaluation of Dyspnea, Pulmonary VentIlation and DIaphragmatic Function in de Novo Adult Acute Respiratory Failure.

Modern management of acute respiratory failure aims to relieve dyspnea and anxiety by providing a non-invasive respiratory support. This approach tries to avoid endotracheal intubation, patient self inflicted lung injuries (PSILI) and diaphragmatic dysfunction. The present study aims to evaluate dyspnea, pulmonary regional ventilation and diaphragmatic function in patients with hypoxemic acute respiratory failure by different observations, and to bring risk factor for intubation out.

Study Overview

• Status: Completed
• Conditions: Acute Respiratory Failure
• Intervention / Treatment: Other: Diaphragmatic ultrasound and electrical impedance tomography

Detailed Description

Patients aged of 18 years or more, presenting with an acute respiratory failure without hypercapnia will be included in the study. Clinical and biological variables, dyspnea assessment, regional lung ventilation (electrical impedance tomography) and diaphragm function (ultrasound) will be evaluated at inclusion and at 2 hours, 4 hours and 48 hours after inclusion. In case of intubation, diaphragmatic function will be also evaluated with phrenic nerve stimulation technique.

Primary endpoint is intubation at day 7. Secondary endpoints are measurement of dyspnea, pulmonary ventilation and diaphragmatic function, also ventilator free days, ICU length of stay and mortality.

• Study Type: Observational
• Enrollment (Actual): 55

Contacts and Locations

Study Locations

• France
  • Paris, France, 75013
    • Groupe Hospitalier Pitié-Salpêtrière", Intensive care unit

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

Patients with de novo acute respiratory failure

Description

Inclusion Criteria:

• Age > 18

• Acute respiratory insufficiency defined by the three following items :

  1. PaO2/ FiO2 <300
  2. Respiratory rate > 25/min
  3. Oxygen support > 10L/min or High Flow nasal oxygen (HFNO)
• Non opposition by the patient to be included
• Social insurance

Exclusion Criteria:

• Respiratory acidosis (pH < 7,35 PaCO2 > 45mmHg or 6kPa)
• Chronic respiratory disease ( COPD, bronchiectasis…)
• Cardiogenic Acute lung oedema
• Non intubation decision at randomisation
• Contraindication for Electro-impedance tomography-belt placement (chest trauma with rib fractures, thoracic wound, chest tube).
• Uncommunicative patient (Glasgow coma scale <12)
• Guardianship or curators for vulnerable patients.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Patients with de novo acute respiratory failure; The following tests will be performed as part of the research (these tests are usually performed as part of routine care but not routinely and comprehensively): A diaphragmatic ultrasound in the half-seated position. Diaphragmatic excursion and thickening fraction will be measured in the right hemi-diaphragm.; A 10-minute reference acquisition. They will be performed at inclusion, H2, H4 and H48.

Other: Diaphragmatic ultrasound and electrical impedance tomography; A diaphragmatic ultrasound in a half sitting position. The diaphragmatic excursion and the thickening fraction of the right hemi-diaphragm will be measured. - Acquisition of 10 minutes of regional pulmonary ventilation by electrical impedance tomography.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oro-tracheal intubation	Patients who will be intubated within the 7 days after admission in the ICU	7 days after admission in the ICU

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diaphragmatic function	using ultrasonography, measure of diaphragmatic excursion and diaphragmatic thickening in Hertz (Hz)	2 days after inclusion
Diaphragmatic function	Diaphragmatic function evaluation by phrenic nerve stimulation (only for intubated patients).	2 days after inclusion
lung regional ventilation	As measured with Electric Impedance Tomography index measures (inhomogeneity index, end expiratory lung impedance change)	2 days after inclusion
Dyspnea evaluation	Dyspnea evaluation using visual analogue scale applied to dyspnea: from 1 to 10, 1 corresponding to "no breathlessness" and 10 to "maximum breathlessness".	28 days after inclusion
Dyspnea evaluation	Dyspnea evaluation using Respiratory Distress Observation Scale (RDOS)	28 days after inclusion
Mechanical ventilation duration	(only for intubated patients).	28 days after inclusion
ICU length of stay	for all patients	28 days after inclusion
ICU mortality	for all patients	28 days after inclusion

Collaborators and Investigators

• Sponsor: Assistance Publique - Hôpitaux de Paris
• Investigators: Study Director: Martin DRES, MD PhD, Assistance Publique - Hôpitaux de Paris

Study record dates

Study Major Dates

• Study Start (Actual): August 11, 2021
• Primary Completion (Actual): July 22, 2025
• Study Completion (Actual): July 22, 2025

Study Registration Dates

• First Submitted: June 18, 2021
• First Submitted That Met QC Criteria: July 5, 2021
• First Posted (Actual): July 14, 2021

Study Record Updates

• Last Update Posted (Actual): March 6, 2026
• Last Update Submitted That Met QC Criteria: March 5, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: dyspnea; Acute respiratory failure; diaphragm; EIT
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Signs and Symptoms, Respiratory; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Dyspnea
• Other Study ID Numbers: 2021-A00329-32

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

IPD Plan Description

The procedures carried out with the French data privacy authority (CNIL, Commission nationale de l'informatique et des libertés) do not provide for the transmission of the database, nor do the information and consent documents signed by the patients.

Consultation by the editorial board or interested researchers of individual participant data that underlie the results reported in the article after deidentification may nevertheless be considered, subject to prior determination of the terms and conditions of such consultation and in respect for compliance with the applicable regulations.

• IPD Sharing Time Frame: Beginning 3 months and ending 3 years following article publication. Requests out of these time frame can also be submitted to the sponsor
• IPD Sharing Access Criteria: Researchers who provide a methodologically sound proposal.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No