Comparison of Volume Assist Control, Dual Mode and Airway Pressure Release Ventilation.

Study Overview
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Brief Summary
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The aim of the COMIX-R study is to assess the short term physiological effects of 3 ventilation strategies for adult patients with ARDS admitted to intensive care unit

Official Title
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Comparison of Volume Assist Control, Dual Mode and Airway Pressure Release Ventilation: A Physiological Study

Conditions
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ARDS

Intervention / Treatment
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* Other: ventilation strategy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years or older Invasive mechanical ventilation on tracheal probe Acute respiratory distress syndrome, as defined by Berlin conference consensus, during hospitalization in intensive care, Recovery phase of acute respiratory distress syndrome: spontaneous ventilation representing from 20 to 30% of ventilation in APRV mode. No severe acidosis (pH> 7.30) Patient affiliated to or beneficiary of a health care plan Express consent of the patient or his/her SDM Exclusion Criteria: Pneumothorax Contraindication to the insertion of a nasogastric tube with an esophageal balloon Contraindication to the use of Electrical impedance tomography (pacemaker) Pregnancy, lactating or parturient woman

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: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: patients exposed to 3 ventilatory mode in 2 different possible orders
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dual Mode first<br>Four consecutive steps (45 min per step) in the following order: APRV (A), Dual Mode (B) , APRV (A) and VAC (C). (ABAC) | Other: ventilation strategy<br>* Patients are ventilated in randomised order with three different ventilation strategies: volume assist control (constant flow), Dual Mode or Airway Pressure Released Ventilation<br>|
| Experimental: VAC fist<br>Four consecutive steps (45 min per step) in the following order: APRV (A), VAC (C) , APRV (A) and Dual Mode (B). (ACAB) | Other: ventilation strategy<br>* Patients are ventilated in randomised order with three different ventilation strategies: volume assist control (constant flow), Dual Mode or Airway Pressure Released Ventilation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change of PaO2 (mmHg) | Arterial partial pressure of dioxygen Of note: As it is a physiological study, all the primary and secondary outcomes will be analyzed with the same importance. | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| -Respiratory rate variability | variability of rate (per minute) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -expiratory and inspiratory transpulmonary pressure | calculated with the esophageal pressure (cm H20) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -ventilation distribution in the lungs | Electrical impedance tomography (EIT) assess distribution of tidal volume and of end-expiratory lung volume (EELV) (delta Z, IU) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -other arterial parameters of hematosis | pH, PaO2, PaCo2 (mmHg) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -Work of breathing (WOB) | calculated with esophageal pressure (Kg/m) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -Pressure time product (PTP) | -Pressure time product (PTP) calculated with esophageal pressure (cmH2O.s.min-1) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -P0.1 | pressure measured during the first 100 ms after an occlusion (cm H20) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -PEEPi | intrinsic positive end-expiratory pressure (cm H20) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| MAP | mean arterial pressure | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| HR | heart rate (beats per minute) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -Respiratory comfort | visual analogic scale | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -Patient-ventilator asynchronies | numbers of asynchronies analyzed on screen | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes | 
| -Tidal volume variability | variability of Tidal volume (mL) | 15 minutes, 1 hour, 1hour and 45 minutes, 2 hour and 30 minutes |