Feasabilty and Physiological Effects of a Ventilation Strategy Combining PEEP and Tidal Volume Titration According to Inspiratory and Expiratory Transpulmonary Pressures in ARDS Patients.

Study Overview
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Brief Summary
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Expiratory or inspiratory transpulmonary pressures have been proposed to optimize ventilator settings in patients with ARDS. The aim of this study is to assess the feasibility and the physiological effects of a new method based on both expiratory and inspiratory transpulmonary pressures.

Detailed Description
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Expiratory or inspiratory transpulmonary pressures have been proposed to optimize ventilator settings in patients with ARDS. A positive expiratory transpulmonary pressure may be considered as a target to limt the risk of collapse in dependant lung regions. Some authors propose to titrate PEEP to target an inspiratory transpulmonary pressure of 20cmH20 to limit the risk of overdistension in non-dependant regions.The aim of this study is to assess the feasibility and the physiological effects of a new method based on both expiratory and inspiratory transpulmonary pressures.

Official Title
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Feasabilty and Physiological Effects of a Ventilation Strategy Combining PEEP and Tidal Volume Titration According to Inspiratory and Expiratory Transpulmonary Pressures in ARDS Patients..

Conditions
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ARDS, Human

Intervention / Treatment
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* Other: PEEP and Tidal Volume Titration


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 years or older Moderate to severe ARDS Written informed consent obtained from patient' surrogates Exclusion Criteria: Pneumothorax Known pregnancy Contraindication to electrical impedance tomography or esophageal pressure measurements

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Interventional Model Description: feasibility, monocentric, prospective study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Transpulmonary based ventilation strategy<br>PEEP and tidal volume will be set to target expiratory and inspiratory transpulmonary pressures of 0 and 20 cmH2O, respectively. | Other: PEEP and Tidal Volume Titration<br>* PEEP and Tidal Volume Titration According to Inspiratory and Expiratory Transpulmonary Pressures<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ventilation strategy failure | Number of patients with failure criteria (barotrauma, hemodynamic failure, rescue therapy or acidemia) | 48 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Short term physiologicals effects on hemodynamics | Cardiac index assed by Echocardiography (L/min/m^2) | 45 minutes | 
| All-cause mortality at day 28 | All-cause mortality | 28 days | 
| Ventilator-free days at day 28 | Number of alive ventilator free days | 28 days | 
| Short term physiologicals effects on respiratory mechanics | recruited lung volume (mL) | 45 minutes | 
| Short term physiologicals effects on gas exchange | PaO2/FiO2 ratio (mmHg) | 45 minutes | 
| Short term physiologicals effects on gas exchange | VD/VT | 45 minutes | 
| Short term physiologicals effects on gas exchange | PaCO2 (mmHg) | 45 minutes | 
| Short term physiologicals effects on respiratory mechanics | distribution of ventilation assed by electrical impedance tomography (COV, %) | 45 minutes |