Comparison of Proportional Assist Ventilation And Neurally Adjusted Ventilator Assist

Study Overview
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Brief Summary
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In spontaneously breathing mechanically ventilated patients, the adequacy between the patient's demand and the level of respiratory support delivered by the ventilator is a major clinical issue. Neurally adjusted ventilator assist (NAVA) and proportional assist ventilation (PAV) have been developed to adapt the level of assistance to the patient's demand. These two modes have been compared to pressure support ventilation (PSV) but have not been compared to each other.

Official Title
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Breathing Pattern Variability, Respiratory Discomfort and Work of Breathing in Proportional Assist Ventilation And Neurally Adjusted Ventilator Assist

Conditions
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Acute Respiratory Failure

Intervention / Treatment
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* Device: PSV mode
* Device: PAV mode
* Device: NAVA


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Intubated patients. Mechanical ventilation for a respiratory reason. Expected duration of Mechanical ventilation > 48 hrs. Spontaneous breathing. Sedations stopped for more than 24 hours. Exclusion Criteria: - Main contra indications to NAVA: gastro-oesophageal surgery in the previous 12 months, oesophageal obstruction, gastro-esophageal bleeding in the previous 30 days, history of esophageal varices, facial trauma or surgery, neuromuscular diseases, individuals with known or suspected phrenic nerve dysfunction. Main contra indications to PAV: airway leak, body weight <25 kg, neuromuscular diseases. Hemodynamic instability defined as the current administration of vasopressors or inotropic drugs. Severe hypoxemia defined as PaO2/FiO2 ratio <200. Decision to withhold life-sustaining treatment. Pregnant women. Minors < 18 years.

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intubated patients<br>Intubated patients: The three modes (PSV, PAV, NAVA) will be applied in random order to each mechanically ventilated patient included in the study. | Device: PSV mode<br>* Application of PSV in all patients<br>Device: PAV mode<br>* Application of PAV mode in all patients<br>Device: NAVA<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Breathing pattern variability | The coefficient of variation (standard deviation divided by the mean) of the tidal volume (expressed in %) | February 2014 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient-ventilator asynchrony | Prevalence of ineffective efforts and double triggering (expressed as a number of events per minute) | February, 2014 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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NAVA - PAV- Breathing Variability - Asynchrony