Position and Esophageal Pressure

Study Overview
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Brief Summary
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Esophageal pressure measurements are used in moderate/severe Accurate Respiratory Distress SyndromeARDS patients in order to set ventilator settings. There might be variations of the measured value according to the patient position (0° vs 30°) at the time of measurements.

Official Title
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Impact of Patient Position on the Value of Esophageal Pressure. pEsition Study.

Conditions
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Acute Respiratory Distress Syndrome

Intervention / Treatment
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* Other: head-bed position


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years Acute respiratory failure defined by PaO2/FIO2< 300 mmHg or pH<7,35 and pCO2>45mmHg or Moderate or severe Accurate Respiratory Distress Syndrome ARDS defined by: New or worsening respiratory symptoms in the previous week. Bilateral opacities-not fully explained by effusions, lobar/lung collapse, or Nodules Respiratory failure not fully explained by cardiac failure or fluid overload PaO2/FIO2< 200 mmHg and PEEP ≥ 5 cm H2O and VT ≤6 ml/kg of Ideal Body Weight Patient intubated or tracheotomized and receiving mechanical ventilation Indication of esophageal measurement decided by the clinician Exclusion Criteria: Contraindication to naso-gastric tube insertion : Recent gastro-duodenal ulcer Stage III esophageal varices Refractory intracranial hypertension Unstabilized spine fracture Surgical contraindication Burns on more than 20 % of the body surface Underlying disease with a life expectancy of less than one year End-of-life decision before inclusion Pregnant or breast-feeding patients Subject deprived of freedom, minor, subject under a legal protective measure Research team unavailability Lack of medical care plan

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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: head-bed position<br>Head-bed position at 0° for 30 minutes then head-bed position at 30° for 30 minutes | Other: head-bed position<br>* Head-bed position at 0° for 30 minutes then head-bed position at 30° for 30 minutes<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total End-expiratory esophageal pressure | After end-expiratory pause on the ventilator, absolute value of the esophageal pressure is measured (in Head-bed position at 30° then in head-bed position at 0° ) | 30min after change of position | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| End-inspiratory esophageal pressure | After end-inspiratory pause on the ventilator, absolute value of the esophageal pressure is measured (in Head-bed position at 30° then in head-bed position at 0° ) | 30min after change of position | 
| Gastric pressure | After end-expiratory pause and end-inspiratory pause on the ventilator, absolute value of the gastric pressure is measured (in Head-bed position at 30° then in head-bed position at 0° ) | 30min after change of position | 
| End-expiratory lung volume | End-expiratory lung volume is measured with nitrogen wash-in wash-out method, available in the ventilator (in Head-bed position at 30° then in head-bed position at 0° ) | 30min after change of position | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Position patient, Esophageal pressure