Comparative Effects on Diaphragmatic Electrical Activity and Respiratory Pattern of Various Levels of Assistance

Study Overview
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Brief Summary
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Exploration of the effects on diaphragmatic electrical activity (EMG) and on respiratory pattern of various level of assistance delivered by the ventilator in intubated spontaneously breathing patients in pressure support (PS) and in Neurally Adjusted Ventilatory Assist (NAVA) by step by step increasing of the level of assistance. Flow, airway pressure, transesophageal EMG signal and transcutaneous EMG signal will be recorded.

Detailed Description
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Exploration of the effects on diaphragmatic electrical activity (EMG) and on respiratory pattern of various level of assistance delivered by the ventilator in intubated spontaneously breathing patients in pressure support (PS) and in Neurally Adjusted Ventilatory Assist (NAVA) by step by step increasing of the level of assistance. Flow, airway pressure, transesophageal EMG signal and transcutaneous EMG signal will be recorded. Aims of the study: To study the electrical diaphragmatic signal variations and the ventilatory profile variations under various level of assistance (delivered by the ventilator) in PS and in NAVA in intubated spontaneously breathing patients To compare a non invasive technique of diaphragmatic electrical activity recording under various levels of assistance with the invasive reference technique

Official Title
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Comparative Effects on Diaphragmatic Electrical Activity and Respiratory Pattern of Various Levels of Assistance in Pressure Support and in Neurally Adjusted Ventilatory Assist

Conditions
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Respiratory Failure

Intervention / Treatment
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* Other: Titration of various level of assistance


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Patients admitted to the ICU, intubated for acute respiratory failure, and ventilated in PS mode will be eligible for inclusion in the study. Exclusion Criteria: Severe hypoxemia requiring an FIO2 > 0.5 hemodynamic instability (defined as the need for high doses of catecholamines namely ≥ 0.5 μg/kg min- and/or high need in volume resuscitation namely more than two litres of crystalloids in two hours-) oesophageal problem such as hiatal hernia, oesophageal varicosities, oesophageal surgery; active upper gastro-intestinal bleeding; known coagulation disorder; any other contraindication to the insertion of a naso-gastric tube; poor short term prognosis (death expected within the next seven days) age < 18 years old.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Titration of various level of assistance|Exploration of the effects on diaphragmatic electrical activity (EMG) and on respiratory pattern of various level of assistance delivered by the ventilator in intubated spontaneously breathing patients in pressure support (PS) and in Neurally Adjusted Ventilatory Assist (NAVA) by step by step increasing of the level of assistance. Flow, airway pressure, transesophageal EMG signal and transcutaneous EMG signal will be recorded.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Electrical diaphragmatic signal variations and ventilatory profile variations under various level of assistance | To study the electrical diaphragmatic signal variations and the ventilatory profile variations under various level of assistance (delivered by the ventilator) in Pressure and in Neurally adjusted ventilatory assist in intubated spontaneously breathing patients |  | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Compare a non invasive technique of diaphragmatic electrical activity recording under various levels of assistance with the invasive reference technique. | To compare a non invasive technique of diaphragmatic electrical activity recording under various levels of assistance with the invasive reference technique. |  | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Mechanical ventilation, Electrical diaphragmatic activity