Lung Ultrasound Assessment of Postoperative Atelectasis After Mechanical Ventilation With Minimum Driving Pressure

Summary

Brief summary The goal of this clinical trial is to compare two different types of perioperative mechanical ventilation (MV), specifically Protective Mechanical Ventilation (PMV) and MV with the lowest possible Driving Pressure (ΔP), in relation to the appearance of postoperative lung closing, eg atelectasis, in adult patients who are operated. Atelectasis will be evaluated via lung ultrasound.

The main questions it aims to answer are:

* Is MV with lower ΔP better than conventional PMV in keeping lungs more open perioperatively and immediately postoperatively?
* Does MV with lower ΔP decrease hospital stay, Intensive Care Unit (ICU) need and mortality?

Researchers will use lung ultrasound to compare MV with the lowest possible Driving Pressure (ΔP) to Protective Mechanical Ventilation (PMV) to see if any of this is more protective than the other concerning lung atelectasis.

All participants will receive perioperative MV.

Half of them will receive conventional Protective Mechanical Ventilation (PMV). This will include well known generally protective settings for mechanical ventilation of patients, concerning volumes, pressures, respiratory rate, inspiratory gases and ventilation maneuvers.

The rest of participants will be ventilated with the lowest possible Driving Pressure (ΔP). This will be similar to PMV in the chosen volumes, respiratory rate, inspiratory gases and ventilation maneuvers. However, the pressure inside lung at the end of expiration, eg Positive End Expiratory Pressure (PEEP), will be not be preset for every patient. Initially, we will perform a maneuver that will quantify each individual's lung characteristics and mechanics. According to this, we will find the exact PEEP that seems to suit each patients lungs most, and use this perioperatively, trying to provide lungs the best conditions every time.

After the completion of the operation, all the patients will be screened for atelectasis, via lung ultrasound, using a well established protocol for the quantification of atelectasis. The results will be statistically analyzed trying to find if any of the forementioned strategies of mechanical ventilation surpasses the other concerning atelectasis appearance.

Furthermore efficiency of lung oxygen absorption, hospital stay, ICU need and mortality will be noted.

Conditions

• Postoperative Atelectasis
• Postoperative Pulmonary Atelectasis
• Postoperative Pulmonary Complications (PPCs)
• Lung Ultrasonography Score
• Lung Ultrasound

Interventions

PROCEDURE

PEEP titration for Minimum Driving Pressure

This group is mechanically ventilated with Invasive Mechanical Ventilation with Volume Control Ventilation mode with PEEP Initially 8 cm H2O. Afterwards, the lungs are recruited with the aforementioned maneuver. During subsequent derecruitment, PEEP is decreased by 2 cm H20 and compliance is noted in each stage. The goal is to find PEEP with maximum compliance (Cmax). A new recruitment maneuver follows and during derecruitment PEEP is set at the optimum value that was previously defined. VT 8 ml/kg IBW RR --\> PaCO2 = 35-45 mmHg FiO2 0.4 - 0.5 --\> SpO2 \> 93% Recruitment Maneuver (as described) every hour

PROCEDURE

Lung Protective Ventilation

This group is mechanically ventilated with Invasive Mechanical Ventilation with Volume Control Ventilation mode with PEEP 8 cm H2O. VT 8 ml/kg IBW RR --\> PaCO2 = 35-45 mmHg FiO2 0.4 - 0.5 --\> SpO2 \> 93% Recruitment Maneuvers (as described) every hour

Sponsors & Collaborators

• University General Hospital of Patras

  lead OTHER

Principal Investigators

• Diamanto Aretha, A. Professor · University of Patras

• Nektaria Xirouchaki, Consultant · University of Crete

• Eumorfia Kondili, Professor · University of Crete

• Antonios Kostouros, Resident · University of Patras

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-10-06

Primary Completion

2025-12-31

Completion

2026-01-15

Countries

• Greece

Study Locations