Open Lung Protective Extubation Following General Anesthesia

Not Applicable

Recruiting

• Conditions: Anesthesia; Ventilator-Induced Lung Injury; Lung Injury; Intra-abdominal Surgery; Atelectasis
• Interventions: Other: Protective "open-lung" extubation; Other: Conventional extubation

• Registration Number: NCT06296173
• Lead Sponsor: Centre hospitalier de l'Université de Montréal (CHUM)

Brief Summary

Perioperative respiratory complications are a major source of morbidity and mortality. Postoperative atelectasis plays a central role in their development. Protective "open lung" mechanical ventilation aims to minimize the occurrence of atelectasis during the perioperative period. Randomized controlled studies have been performed comparing various "open lung" ventilation protocols, but these studies report varying and conflicting effects. The interpretation of these studies is complicated by the absence of imagery supporting the pulmonary impact associated with the use of different ventilation strategies. Imaging studies suggest that the gain in pulmonary gas content in "open lung" ventilation regimens disappears within minutes after the extubation. Thus, the potential benefits of open-lung ventilation appear to be lost if, at the time of extubation, no measures are used to keep the lungs well aerated. Recent expert recommendations on good mechanical ventilation practices in the operating room conclude that there is actually no quality study on extubation.

Extubation is a very common practice for anesthesiologists as part of their daily clinical practice. It is therefore imperative to generate evidence on good clinical practice during anesthetic emergence in order to potentially identify an effective extubation strategy to reduce postoperative pulmonary complications.

Detailed Description

The aim of this study is to establish the feasibility of a multicenter randomized controlled clinical trial comparing two clinical strategies called "open lung" and "conventional" during extubation. The investigators also aim to estimate the rates of postoperative pulmonary complications in the two intervention groups.

METHODS

A multicenter internal pilot, prospective, randomized, allocation-concealed and controlled assessor-blinded study. Two hundred sixteen patients scheduled to undergo elective intra-abdominal surgery requiring general anesthesia and planned hospitalization at four Canadian hospitals, and at moderate or high risk of postoperative pulmonary complications according to the ARISCAT score will be recruited. Following the administration of standardized mechanical ventilation and after obtaining consent, participants will be randomly assigned to two groups:

Group A: Intervention group, "open lung" extubation strategy Group B: Control group, "conventional" extubation strategy.

The rate of adherence to the extubation protocol, the weekly patient recrutement rate and the 7-day postoperative pulmonary complications outcome completion rate will be measured. We will only report secondary efficacy outcome in aggregate as they will be rolled over to the definitive trial.

Study Timeline

• Study First Submitted: 2024-02-21
• Study First Submitted QC: 2024-02-28
• Study First Posted: 2024-03-06
• Study Start: 2024-10-08
• Status Verified: 2025-01
• Last Update Submitted: 2025-01-16
• Last Update Posted: 2025-01-17
• Primary Completion: 2025-12-01
• Study Completion: 2026-04-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 270

Inclusion Criteria

• Adult patients (18 years of age or over)
• Elective intra-abdominal surgery under general anesthesia.
• Moderate or high risk of postoperative pulmonary complication according to the ARISCAT score (score of 26 or more)
• Planned postoperative hospitalization

Exclusion Criteria

• Expected or known difficult intubation according to the treating anesthesiologist
• Postoperative mechanical ventilation (planned or unplanned)
• General anesthesia performed outside the main operating room

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Open lung extubation	Protective "open-lung" extubation	Before emergence from anesthesia, the patient will be positioned at 30 degrees, and oropharyngeal secretions will be suctioned. Anesthetic gas or intravenous agents will be stopped. Oxygen levels will be set to 50% with a fresh gas flow of at least 10 L/min. Ventilation mode will switch to pressure support adjusted to achieve similar volumes as controlled ventilation. PEEP levels will remain unchanged, while the minimum respiratory rate will decrease by 4 breaths/min. The inspiratory flow for triggering will be set at 2 L/min.
Conventional extubation	Conventional extubation	Before emergence from anesthesia, the patient will be kept supine and oropharyngeal secretions will be suctioned. Anesthetic gas or IV agents will be stopped. Oxygen concentration will be inscreased to 100% with a fresh gas flow ≥10 L/min. The ventilator will be halted, APL valve opened to atmosphere, and the patient manually ventilated with the reservoir bag until spontaneous breathing resumes, followed by manual assistance as deemed necessary by the anesthesiologist.

Primary Outcome Measures

Name	Time	Method
Average weekly patient recruitment rate	Every week. At the end of the study (average 9 months) at the study level.	Achieve a weekly patient recruitment rate of 2 patients per week per center
Protocol adherence rate	At the end of surgery for individual assessments. At the end of the study (average 9 months) at the study level.	Assess adherence to a protocol during emergence from anesthesia, monitoring four criteria (proper positioning (dorsal decubitus or semi-sitting position), correct FiO2 (100% or 50%), appropriate ventilatory mode (manual or pressure support ventilation), and proper end-expiratory pressure (zero or preserved end-expiratory pressure), and noting deviations, with adherence defined as successful performance of all criteria during extubation.
Postoperative pulmonary complications outcome completion rate	At postoperative day 7 for individual assessments. At the end of the study (average 9 months) at the study level.	Postoperative pulmonary complications are defined as a composite endpoint that includes atelectasis, pneumonia, acute respiratory distress syndrome, and pulmonary aspiration, according to the StEP-COMPAC definition.

Secondary Outcome Measures

Name	Time	Method
Health-related quality of life	At postoperative day 90	Evaluated using the EQ-5D-5L questionnaire completed during a telephone interview
Accuracy of self-reported protocol adherence compared to directly observed protocol adherence	At the end of the surgery	Following emergence from general anesthesia, treating anesthesiologists will complete the same four-point scoring sheet as the research assistant to self-report protocol adherence.
Postoperative pulmonary complications	At postoperative day 7	Postoperative pulmonary complications are defined as a composite endpoint that includes atelectasis, pneumonia, acute respiratory distress syndrome, and pulmonary aspiration, according to the StEP-COMPAC definition.
Amount of supplemental oxygen administered following discharge from the post-anesthesia care unit	At postoperative day 7 or hospital discharge (earliest of the two)	Obtained from the electronic medical record or the handwritten vital signs sheet. Calculated as %.h-1
Quality of recovery	At postoperative day 1	Evaluated using the QoR-15 questionnaire completed at the bedside.
Discharge disposition	At postoperative day 30	Location to which patient is discharged (e.g., home, long term care facility, etc.) Assessed during telephone interview and using administrative data. We will
Days alive and out of hospital	At postoperative day 30	Assessed during telephone interview and using administrative data

Trial Locations

Locations (4)

The Ottawa Hospital; 🇨🇦 Ottawa, Ontario, Canada

Unity Health Network; 🇨🇦 Toronto, Ontario, Canada

Centre Hospitalier de l'Université de Montréal (CHUM); 🇨🇦 Montréal, Quebec, Canada

CHU de Québec - Université Laval; 🇨🇦 Québec, Canada