Association Between Driving Transpulmonary Pressure and Extravascular Lung Water in Patients With ARDS

Study Overview
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Brief Summary
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Intubated patients with the acute respiratory distress syndrome (ARDS) are usually treated with protective ventilation limiting plateau pressure below 30 centimeter of water (cmH2O) and, if possible, a driving pressure under 15 cmH2O. However, these airway pressures might not reflect the actual pressure applied to the lung. Transpulmonary pressure is the difference between airway pressure and pleural pressure, the latter is estimated by the esophageal pressure, and so it better reflects the ventilatory induced lung injury (VILI). One of the consequences of the VILI is a increase of pulmonary edema and it could be estimated by the extravascular lung water, obtained by trans-pulmonary thermodilution. So it could exist a link between the driving trans-pulmonary pressure and the extravascular lung water.

Official Title
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Association Between Driving Transpulmonary Pressure and Extravascular Lung Water in Patients With ARDS

Conditions
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Acute Respiratory Distress Syndrome

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Acute respiratory distress syndrome (ARDS) Monitoring with a transpulmonary thermodilution device Esophageal pressure monitoring Exclusion Criteria: Legal protection measures Pregnancy Contra-indications of esophageal catheter : esophageal varicose, severe coagulopathy

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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association between the transpulmonary driving pressure and the extravascular lung water (EVLW) | On the first day of patient's respiratory and hemodynamics monitoring, we will collect transpulmonary driving pressure and extra-vascular lung water values. We will calculate the correlation coefficient linking these two variables to assess if their association. | From inclusion up to hospital discharge (maximum day 60) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association between the transpulmonary driving pressure and the pulmonary vascular permeability index (PVPI) | On the first day of patient's respiratory and hemodynamics monitoring, we will collect transpulmonary driving pressure and PVPI values. We will calculate the correlation coefficient linking these two variables to assess if their association. | From inclusion up to hospital discharge (maximum day 60) | 
| Correlation between the transpulmonary driving pressure at admission and the ICU-mortality | Multivariable analysis of factors associated with ICU mortality, including initial severity, comorbidities, respiratory mechanics covariates, EVLW and pulmonary vascular permeability index (PVPI). | From inclusion up to hospital discharge (maximum day 60) | 
| Correlation between the extravascular lung water at admission and the ICU-mortality | Multivariable analysis of factors associated with ICU mortality, including initial severity, comorbidities, respiratory mechanics covariates, EVLW and pulmonary vascular permeability index (PVPI). | From inclusion up to hospital discharge (maximum day 60) | 
| Influence of position on plateau pressure | Plateau pressure will be measured at 0°, 30° and 45° position and we will compare the values to assess if the position impacts this pressure. | From inclusion up to hospital discharge (maximum day 60) | 
| Influence of position on plateau pressure on esophageal pressure | Esophageal pressure will be measured at 0°, 30° and 45° position and we will compare the values to assess if the position impacts this pressure. | From inclusion up to hospital discharge (maximum day 60) | 
| Influence of position on plateau pressure on transpulmonary pressure | Transpulmonary pressure will be measured at 0°, 30° and 45° position and we will compare the values to assess if the position impacts this pressure. | From inclusion up to hospital discharge (maximum day 60) | 
| Influence of position on plateau pressure on intra-abdominal pressure | Intra-abdominal pressure will be measured at 0°, 30° and 45° position and we will compare the values to assess if the position impacts this pressure. | From inclusion up to hospital discharge (maximum day 60) |