Inspiratory Work of Breathing Before and After Extubation

NCT07017608 | Recruiting

• 1 other identifier: 19-5879
• Study Type: observational
• Target: 67
• Locations: 1 country
• Sites: 1

Brief Summary

Critically ill patients who (1) are not able to maintain their airway, (2) cannot breathe on their own, or (3) both, are ones who often require tracheal intubation and support from a breathing machine (mechanical ventilator). When the patient is ready to be liberated from the mechanical ventilator because the initial insult for intubation has been resolved, the patient is screened using the readiness to wean test in preparation for extubation. As the patient passes this screening, a spontaneous breathing test (SBT) is initiated. Currently, there are many debates surrounding which SBT technique is most favorable. At Toronto General Hospital, the clinical team uses a zero-end expiratory pressure (ZEEP) trial. Once the patient successfully passes their SBT they are then extubated. The patient will undergo a spontaneous breathing trial of continuous positive airway pressure (CPAP) of 5 cmH2O and ZEEP, in which time the investigators will be using a new technology called electrical impedance tomography (EIT), to study and compare the end expiratory lung volume (EELV); investigators will use an esophageal catheter to measure and monitor pressures in the lung, and also assess the patient's work of breathing. This will be repeated once the patient has been extubated safely.

Conditions

Lung Transplant; Complications; Ventilator-Induced Lung Injury; Ventilator Associated Pneumonia

Outcome Measures

Primary Outcomes (2)

• Change in end-expiratory lung volume (EELV) between the varying conditions (CPAP 5, ZEEP, and post-extubation).

  End-expiratory lung volume is assessed using Electrical Impedance Tomography (EIT) and expressed in milliliters (mL) across all three conditions: 1. CPAP 5 cm H₂O 2. ZEEP (Zero End-Expiratory Pressure) 3. Post-extubation

  Up to 30 minutes after extubation

• Discriminative ability of occlusion maneuvers to detect expiratory muscle effort

  The ability of occlusion maneuvers to detect presence of expiratory muscle effort, measured with the gold standard (gastric pressure), will be assessed with receiver operating characteristic curves.

  Up to 30 minutes after spontaneous breathing trial initiation

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

Eligible patients admitted to the medical surgical intensive care unit (MSICU) at Toronto General Hospital (TGH) requiring invasive mechanical ventilation, after obtaining consent. Inclusion will be stratified in a 1:1 ratio between lung transplant and non-transplant patients.

You may qualify if:

• Adult patients intubated and ventilated

You may not qualify if:

• Contraindication for esophageal catheter insertion: upper gastrointestinal surgery within prior 6 weeks, actively bleeding esophageal varices
• Bronchopleural fistula
• Contraindication for electrical impedance tomography: chest burns, skin lesions in the thorax, chest wall bandaging limiting electrode placement, unstable spinal lesions or fractures
• Pregnancy

Sponsors & Collaborators

• University Health Network, Toronto: lead

Study Sites (1)

Toronto General Hospital, University Health Network

Toronto, Ontario, M5G2C4, Canada

RECRUITING

MeSH Terms

Conditions

Ventilator-Induced Lung Injury; Pneumonia, Ventilator-Associated

Condition Hierarchy (Ancestors)

Lung Injury; Lung Diseases; Respiratory Tract Diseases; Healthcare-Associated Pneumonia; Cross Infection; Infections; Pneumonia; Respiratory Tract Infections; Iatrogenic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Ewan Goligher, MD

  University Health Network, Toronto

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Glauco Plens, MD

CONTACT

416-340-4800; Glauco.Plens@uhn.ca

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Ewan C Goligher, MD, PhD

Study Record Dates

• First Submitted: May 23, 2025
• First Posted: June 12, 2025
• Study Start: September 1, 2020
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: June 12, 2025

Record last verified: 2025-05

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)