Estimation of P0.1 Using Ultrasound Indexes of Diaphragm Function

NCT07564258 | Not Yet Recruiting

• 1 other identifier: APHP260589
• Study Type: observational
• Target: 40
• Locations: 0 countries
• Sites: N/A

Brief Summary

Occlusion pressure at 100 ms (P0.1) is a reliable and non-invasive index of inspiratory drive that can be measured easily on most ventilator. Unfortunately, P0.1 cannot be measured reliably in non-intubated patients. In those receiving non-invasive ventilation, the measurement of P0.1 might be inaccurate due to leaks. P0.1 cannot be measured at all in patients receiving high-flow nasal canulae (HFNC). Ultrasound indices of diaphragm contractile function, namely diaphragm excursion, velocity and thickening fraction, could be reliable and non-invasive proxies of respiratory drive in non-intubated patient. Our hypothesis is that ultrasound indices of diaphragm function may reliably estimate P0.1. To validate this hypothesis, theses indices will be measured simultaneously with P0.1 in intubated patients, during diaphragm loading conditions similar to spontaneous breathing: the spontaneous breathing trial (SBT). The SBT is used to evaluate if patients can breathe without the assistance provided by the ventilator, and thus, be weaned from mechanical ventilation.

Conditions

Acute Respiratory Disease

Keywords

acute respiratory failure; respiratory drive; P0.1; Airway occlusion pressure; Diaphragm; ultrasonography doppler

Outcome Measures

Primary Outcomes (1)

• P0.1 and Peak contraction velocity 5 minutes after the initiation of the SBT

  Airway occlusion pressure measured 100 ms after the initiation of the inspiration, compared to peak contraction velocity of the diaphragm, measured by subcostal ultrasound in TDI-mode

  5 minutes after the initiation of the SBT

Secondary Outcomes (8)

• P0.1 and EXdi

  Immediately after the initiation of the SBT then 5, 10, 15, 20, 25 and 30 minutes after the initiation of the SBT

• P0.1 and Peak contraction velocity

  Immediately after the initiation of the SBT then 10, 15, 20, 25 and 30 minutes after the initiation of the SBT

• P0.1 and EXdi,0.1

  Immediately after the initiation of the SBT then 10, 15, 20, 25 and 30 minutes after the initiation of the SBT

• P0.1 and Velocity Time Integral

  Immediately after the initiation of the SBT then 10, 15, 20, 25 and 30 minutes after the initiation of the SBT

• P0.1 and Peak relaxation velocity

  Immediately after the initiation of the SBT then 10, 15, 20, 25 and 30 minutes after the initiation of the SBT

Interventions

Spontaneous breathing trial DEVICE

A plateau pressure measurement will be performed before starting the spontaneous breathing trial (SBT). Then, immediately and 5, 10, 15, 20, 25, and 30 minutes after the start of the SBT, the following will be performed as part of the study: * Subcostal diaphragmatic ultrasound: M-mode and tissue Doppler * Lateral diaphragmatic ultrasound: 2D mode and M-mode * Measurement of P0.1 * Measurement of Pocc during a tele-expiratory pause, only 5 minutes after the start of the SBT.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients admitted to the intensive care unit who are intubated or have undergone a tracheostomy.

You may qualify if:

• \- Age ≥ 18 years old
• Patient intubated or tracheostomized
• Decision by the clinician in charge to initiate a SBT
• After information, the patient or next of kind did not refuse to participate (according to the French law, written informed consent is waived)

You may not qualify if:

• \- Suspicion of diaphragmatic nerves injury
• Preexisting neuromuscular disease
• Spinal cord injury above C5
• Neuromuscular blockade within last 24 hours
• Body mass index \> 40 kg/m2
• Pregnancy or breast feeding
• Patient under legal protection

Sponsors & Collaborators

• Assistance Publique - Hôpitaux de Paris: lead

Study Design

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

Study Record Dates

• First Submitted: April 27, 2026
• First Posted: May 4, 2026
• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): January 1, 2027
• Last Updated: May 4, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ICF
• 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
• Access Criteria: Researchers who provide a methodologically sound proposal.