Optimization of Arterial Oxygen Transport by Positive End-expiratory Pressure Variation in Acute Respiratory Distress Syndrome

Study Overview
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Brief Summary
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Despite improving in the treatment of acute respiratory distress syndrome (ARDS), this affection keep an elevate rate of death. The strategy of mechanical ventilation is more and more under definite protocol, following large strength randomized studies. Although, it doesn't exist today element allowing to adjust the level of Positive End-Expiratory Pressure (PEEP) with improvement in patient's survival. The investigators proposed in this study to determinate the level of PEEP adjust to obtain the better arterial oxygen transport (TaO2). The investigators going to conduct a physiologic, observational, none controlled study. All patients hospitalized in intensive care unit of Pontchaillou hospital with ARDS criteria and without specific exclusion criteria will be included. Primary objective is to looking for the optimum level of PEEP for TaO2.

Official Title
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Optimization of Arterial Oxygen Transport by Positive End-expiratory Pressure Variation in Acute Respiratory Distress Syndrome

Conditions
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Respiratory Distress Syndrome, Adult

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patient presenting a Acute Respiratory Distress Syndrone (ARDS) definite by : acute respiratory failure, bilateral alveolo-interstitial infiltrate on chest radiography, absence of increased left ventricular filling pressure, partial pressure of oxygen in arterial blood (PaO2)/Fraction of inspired oxygen(FiO2) <200 and Positive End-Expiratory Pressure (PEEP) > or equal to 5 cmH2O Need to invasive mechanical ventilation Precedent criteria persisting at least 6 hours Haemoglobin > 8g/dl Ramsay score at 6 Exclusion Criteria: Participation to en other study on the Acute Respiratory Distress Syndrone (ARDS) with the same end-point Presence of external circulatory assist Left Ventricular Ejection fraction (LVEF)or Left ventricular shortening fraction (LVSF)< 40% after correction of hypovolemia and/or vasoplegia Infusion of inotrope Presence of Acute Pulmonary Heart Following procedure : ExtraCorporeal Membrane Oxygenation(ECMO), prone position, inhalation of Nitrogen dioxyde Presence of a chest tube Pregnant or nursing mother Less than 18 years old Complete arrhythmia by atrial fibrillation Person under justice protection

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 |
| --- | --- | --- |
| Determinate the Positive End-Expiratory Pressure (PEEP) level achieving the best arterial oxygen transport (TaO2) |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evolution of pulmonary gas exchanges |  | 1 year | 
| Evolution of respiratory mechanism parameters |  | 1 year | 
| evolution of circulatory parameters and needs of catecholamine during the study |  | 1 year | 
| Appearance of secondary effects due to mechanical ventilation |  | 1 year |