Effect of PEEP Titration on the EELV Measured by the Nitrogen Dilution Technique in ARDS

Study Overview
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Brief Summary
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Mechanical ventilation of the patient with acute respiratory distress syndrome is one of the first therapies.

Detailed Description
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The application of positive end expiratory pressure is recommended but the question remains How to set the best positive end-expiratory pressure (PEEP) level for each patient? . Different titration techniques have been studied on oxygenation and respiratory mechanics parameters without reaching a consensus. Currently we have a module that is connected to the ventilator to collect the patient's lung volume. It will therefore allow us to optimize the settings of the ventilator and to set the best level of positive end-expiratory pressure best peep in order to individualize our treatment for each patient.

Official Title
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Effect of Positive End Expiratory Pressure Titration on the End-expiratory Lung Volume Measured by the Nitrogen Dilution Technique in Acute Respiratory Distress Syndrome

Conditions
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Acute Respiratory Distress Syndrome

Intervention / Treatment
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* Procedure: End-expiratory lung volume measurement and incremental PEEP titration


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients admitted to intensive care with a diagnosis of moderate to severe ARDS in accordance with the Berlin criteria, i.e. a PAFI <200 and PEEP >5cm H20 ratio Diagnosis of ARDS made within 72 hours Age over 18 years Informed consent of the patient and/or trusted person where applicable Exclusion Criteria: Start of mechanical ventilation more than 72 hours prior to inclusion. SDRA evolving for more than 72 hours Presence of major hemodynamic instability with mean blood pressure <60mmhg, and/or heart rate <45 bpm or >150bpm with an increase in vasopressor amine dosage of more than 20% over the last 6 hours. Intracranial hypertension with CPP<60mmhg Massive hemoptysis requiring immediate surgical or interventional radiology procedure Tracheal surgery (except intensive care tracheotomy) or sternotomy within the previous 15 days Trauma or surgery of the face in the previous 15 days. Deep vein thrombosis treated for less than 2 days Pacemaker implantation in the last 2 days Unstable fracture (spine, femur or pelvis) Respiratory reasons use of extracorporeal oxygenation nitric oxide pleural drainage system with bronchopleural gap pulmonary transplantation Poor respiratory tolerance per procedure with desaturation Spo2<85%. Poor hemodynamic tolerability per procedure combining hypotension with MAP<65mmhg and a 20% increase in norepinephrine dosage. Lack of patient consent to proceed minor patient lack of consent

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: experimental procedure<br>end-expiratory lung volume measurement procedure according to the PEEP level set by the clinician, respecting a Vt at 6ml/kg IBW and Pplat<28cmH2o incremental PEEP titration procedure in 5 steps starting from 5cmH2o up to 20cmH2o | Procedure: End-expiratory lung volume measurement and incremental PEEP titration<br>* End expiratory lung volume measurement procedure according to the PEEP level set by the clinician, respecting a Vt at 6ml/kg IBW and Pplat<28cmH2o incremental PEEP titration procedure in 5 steps starting from 5cmH2o up to 20cmH2o<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Observe end-expiratory lung volume change during an increasing PEEP titration procedure in patients with moderate to severe ARDS |  | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Define a threshold of end-expiratory lung volume variation to help determine optimal PEEP |  | 1 day | 
| Analyzing the effect of PEEP titration on static compliance and dynamic strain |  | 1 day | 
| Effect of PEEP titration on hematosis via the calculation of the Pao2/Fio2 ratio for each PEEP step thanks to the measurement of Pao2 on arterial gasometry |  | 1 day | 
| Study the correlation between % change in end-expiratory lung volume and improvement in hematosis (Pao2/Fio2) |  | 1 day | 
| Compare end-expiratory lung volume variations according to the type of ARDS (severity, focal or diffuse, pulmonary or extra-pulmonary etiology) |  | 1 day | 
| Evaluate the hemodynamic tolerance of this procedure with the mean arterial pressure obtained by invasive blood pressure, noradrenaline dosage variation per procedure, lactate (obtained by arterial blood gas) |  | 1 day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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respiratory distress, titration, end-expiratory