Effects of Extravascular Lung Water on Prone Position Efficacy in Patients With ARDS

Study Overview
=================
Brief Summary
-----------------
The study will investigate the influence that extravascular lung water index (EVLWi) could have on the efficacy and persistance of efficacy of prone position in patients with acute respiratory distress syndrome. Prone position will increase blood oxygenation in 75% of the cases and will be persistant in half of the cases. Unfortunately, no clinical criteria has been found correlated with efficacy. The quantity of lung edema, with increased lung weight, could be a determinant factor of efficacy and the persistance of the efficacy. EVLWi, assessed with the PiCCO2 device, reflects the quantity of fluid accumulated in interstitial and alveolar spaces. The hypothesis is that patients with higher EVLWi will have less efficacy of prone position in oxygenation and also that the beneficial effects of prone position will last shorter compared to patients with lower EVLWi.

Official Title
-----------------
Effects of Extravascular Lung Water on Prone Position Efficacy in Patients With Acute Respiratory Distress Syndrome

Conditions
-----------------
Acute Respiratory Distress Syndrome, Acute Respiratory Distress Syndrome in Adult or Child

Intervention / Treatment
-----------------
* Other: Prone position in patients with ARDS


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age ≥18 years Presence of acute respiratory distress syndrome Decision to perform prone position according to the physician in charge of the patient Hemodynamic monitoring with a PiCCO2 device (Pulsion Medical Systems, Feldkirchen, Allemagne) Exclusion Criteria: Absence of affiliation to the French Sociale security Patient under a tutelage measure or placed under judicial protection Known pregnancy Currently receiving ECMO therapy

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 99 Years

Sexes Eligible for Study
-----------------
All

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| patients with ARDS<br> | Other: Prone position in patients with ARDS<br>* Transpulmonary thermodilution, arterial blood gas and recruitment/inflation calculation will be made every 8 hours: at baseline (just before prone position), after eight hours of prone position, after 16 hours of prone position (end of prone position), after 24 hours ( 8 hours after the end of prone position).<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between extravascular lung water index (EVLWi) just before prone position (baseline) and the time course of the partial arterial pressure in oxygen over inspired fraction of oxygen (PaO2/FiO2) ratio during prone position. | EVLWi is the amount of water contained in the lungs outside the pulmonary vasculature. It can be measured using the transpulmonary thermodilution technique with the PiCCO2 device (Pulsion Medical Systems, Feldkirchen, Germany) | up to 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between extravascular lung water index (EVLWi) just before prone position (baseline) and the time course of the recruitment/inflation ratio during prone position. | recruitment/inflation ratio is a validated method to characterize the lung recruitability with high positive expiratory pressure, at the bedside of patients with ARDS | up to 24 hours | 
| Correlation between extravascular lung water index (EVLWi) at the end of prone position and the time course of the partial arterial pressure in oxygen over inspired fraction of oxygen (PaO2/FiO2) ratio in the next eight hours after prone position | EVLWi is the amount of water contained in the lungs outside the pulmonary vasculature. It can be measured using the transpulmonary thermodilution technique with the PiCCO2 device (Pulsion Medical Systems, Feldkirchen, Germany) | up to 24 hours | 
| Correlation between extravascular lung water index (EVLWi) at the end of prone position and the time course of the recruitment/inflation ratio in the next eight hours after prone position. | recruitment/inflation ratio is a validated method to characterize the lung recruitability with high positive expiratory pressure, at the bedside of patients with ARDS | up to 24 hours | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
ARDS, Prone Position, Extravascular lung water, Lung recruitment