Comparison of Breathing Pattern During Neurally Adjusted Ventilatory Assist Ventilation and Pressure Support Ventilation

Study Overview
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Brief Summary
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Comparison of Breathing pattern during mechanical ventilation. Two modes of mechanical ventilation are compared (Pressure Support Ventilation and Neurally Adjusted Ventilatory Assist)

Detailed Description
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Eligibility : healthy subject without respiratory complications in the past Subjects will breath spontaneously without mechanical ventilation, with Pressure Support Ventilation and with Neurally Adjusted Ventilatory Assist during. Three levels of pressurisation will be tested : 5 cmH2O, 8 cmH2O and 12 cmH2O Duration of each condition will be about 15 minutes. Measurements will include:Flow, airway pressure, SaO2, PtCO2, diaphragmatic electromyography, chest wall motion by optoelectronic plethysmography

Official Title
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Comparison of Breathing Pattern During PSV and NAVA

Conditions
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Respiratory System Abnormalities

Intervention / Treatment
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* Device: Servo-i® ventilator, MAQUET,Critical Care, Sweden


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 years Healthy Subject without any chronic disease Exclusion Criteria: Absence of consent Pregnant

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Pressure Support Ventilator<br>Gold standard partial ventilator support: Pressure Support Ventilation performed with Servo-i® ventilator (MAQUET,Critical Care, Sweden). During pressure support the inspiratory muscles are assisted by a constant inspiratory pressure adjusted by the prescriptor and applied to the airway by either an invasive or a non invasive interface. Then the subject initiate the inspiratory effort and a constant pressure is delivered to the airway in order to assist inspiration. Three levels of pressure will be tested (5 cmH2O, 8 cmH2O and 12 cmH2O) | Device: Servo-i® ventilator, MAQUET,Critical Care, Sweden<br>* Electrical activity of the diaphragm will be obtained through a naso-gastric tube with multiple array of electrodes placed at its distal end (Eadi catheter® , Maquet Critical Care, Sweden). Subject will be ventilated with a mouthpiece interface. NAVA will be compared to Pressure Support using the same ventilator. Once the pattern of breathing will be stabilized (10 minutes) in each condition (see arm) the following parameters will be recorded during 5 minutes and compared : tidal volume, inspiratory time, expiratory time, transcutaneous CO2 pressure, diaphragmatic Emg activity, delay between the inspiratory activity initiation and positive pressure initiation, delay between the end of the inspiratory effort and the end of pressurisation.<br>* Other names: PSV;|
| Experimental: NAVA<br>Spontaneous Breathing using Neurally Adjusted Ventilatory Assist with trigger adjusted on diaphragmatic electromyogram. Electrical activity of the diaphragm will be obtained through a naso-gastric tube with multiple array of electrodes placed at its distal end (Eadi catheter® , Maquet Critical Care, Sweden). During NAVA the inspiratory muscles are assisted by a pressure which is proportional to this electrical activity. Then the subject initiate the inspiratory effort and a pressure proportional to the integrated EMG activity is delivered to the airway in order to assist inspiration. The adjustment of the level of NAVA (expressed in cmH2O/microvolt) will be adjusted in order to obtain a peak pressure similar to pressure support (5 cmH2O, 8 cmH2O and 12 cmH2O) | Device: Servo-i® ventilator, MAQUET,Critical Care, Sweden<br>* Electrical activity of the diaphragm will be obtained through a naso-gastric tube with multiple array of electrodes placed at its distal end (Eadi catheter® , Maquet Critical Care, Sweden). Subject will be ventilated with a mouthpiece interface. NAVA will be compared to Pressure Support using the same ventilator. Once the pattern of breathing will be stabilized (10 minutes) in each condition (see arm) the following parameters will be recorded during 5 minutes and compared : tidal volume, inspiratory time, expiratory time, transcutaneous CO2 pressure, diaphragmatic Emg activity, delay between the inspiratory activity initiation and positive pressure initiation, delay between the end of the inspiratory effort and the end of pressurisation.<br>* Other names: PSV;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparison of breathing pattern during pressure support and Neurally Adjusted Ventilatory Assist (NAVA) |  | 2h | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Tidal volume evaluated by optoelectronic plethysmography |  | 2h | 
| Electrical diaphragmatic activity recorded by mechanical ventilator |  | 2h | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Breathing Pattern, Mechanical Ventilation, Pressure support ventilation, Neurally Adjusted Ventilatory Assist