Frequency and Severity of Respiratory Acidosis During One-lung Ventilation, a Retrospective Pilot Study to Compare Clinician Settings and Those Proposed by the VentilO Application

Recruiting

• Conditions: Acidosis; Thoracic; Hypercapnia; One Lung Ventillation (OLV); Smartphone Application; Surgery; Mechanical Ventilation

• Registration Number: NCT07099963
• Lead Sponsor: Laval University

Brief Summary

One-lung ventilation is a mechanical ventilation method frequently used during several thoracic surgeries. One-lung ventilation requires the use of protective ventilation to limit ventilator-induced injury and reduce postoperative respiratory complications. Protective ventilation during one-lung ventilation is specific since tidal volumes are applied by definition to one lung, and it is recommended to use lower tidal volumes, down to 4 ml/kg of ideal body weight. This approach requires individualized ventilation parameters, which differs from the conventional or two-lung ventilation, and there are no clear recommendations regarding respiratory rate adjustment to ensure adequate gas exchange.

Detailed Description

The aim of the study is to:

1. Evaluate whether the initial ventilation settings (tidal volume and respiratory rate) during one-lung ventilation are appropriate to prevent respiratory acidosis.

2. Compare the ventilation settings (tidal volume and respiratory rate) made by clinicians with those proposed by an smartphone application ''VentilO''.

Study Timeline

• Study First Submitted: 2025-07-02
• Study First Submitted QC: 2025-07-30
• Status Verified: 2025-08
• Study Start: 2025-08-01
• Study First Posted: 2025-08-01
• Last Update Submitted: 2025-08-01
• Last Update Posted: 2025-08-06
• Primary Completion: 2025-12
• Study Completion: 2026-06-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

• Adults (≥ 18 years old)
• Patients intubated and undergoing one-lung ventilation during thoracic surgery
• Volume-controlled ventilation mode used intraoperatively

Exclusion Criteria

• Arterial blood gas data unavailable during one-lung ventilation
• Missing demographic data (sex, height, actual weight)

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Respiratory acidosis	20 minutes after initiation of one lung ventilation after lung isolation	The frequency of respiratory acidosis on arterial blood gases after 20 minutes of mechanical ventilation (pH \< 7.35 and PaCO2 \> 45mmHg) measured by arterial blood gases

Secondary Outcome Measures

Name	Time	Method
Mechanical Ventilation duration	Up to 90 days	Time spent with invasive mechanical ventilation during surgery and hospital stay
Hospital length of stay	Up to 90 days	Recovery room admission through hospital discharge
Acid-base disorder	At the beginning of one lung ventilation during the surgery	Presence of Respiratory alkalosis define by pH\>7.45 and PaCO2 \< 35 mmHg
Respiratory rate	At the beginning of one lung ventilation during the surgery	Respiratory rate set by the doctor, this respiratory rate will be compared to the suggestion of the algorithm
Number of participants with hemodynamic shock - hypotension	Day 1	Requiring \>1L of volume repletion and/or use of amines at \>0.05 mcg/kg/min or norepinephrine equivalent
Hospital mortality	Up to 90 days	Occurence of death during hospital stay

Trial Locations

Locations (1)

Institut universitaire de cardiologie et de pneumologie de Québec - Université Laval; 🇨🇦 Quebec, Canada