Neurally Adjusted Ventilatory Assist and Synchrony in Patients With Chronic Obstructive Pulmonary Disease (COPD)

Study Overview
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Brief Summary
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NAVA used the electrical activity of the diaphragm (EAdi) to initiate and deliver in proportion of an inspiratory assistance. During inspiration, EAdi signal occurred earlier than airflow or pressure variations in the airway. The investigators hypothesized that NAVA improved patient-ventilator synchrony and reduced inspiratory workload as compared with pressure support ventilation delivered at two different cycling criteria (25 and 50 %).

Official Title
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Effect of Mechanical Ventilation With NAVA and PSV on Inspiratory Muscle Workload and Synchrony in Patients With Chronic Obstructive Pulmonary Disease

Conditions
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Chronic Obstructive Pulmonary Disease

Intervention / Treatment
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* Device: NAVA
* Other: Expiratory trigger (ET)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: History of chronic obstructive pulmonary disease Admitted for acute respiratory failure requiring invasive mechanical ventilation Currently receiving pressure support ventilation Exclusion Criteria: Age < 18 years Respiratory rate > 35 bpm Severe hypoxemia with SpO2 < 88 % and FIO2 > 50 % Heart rate > 120 bpm Systolic arterial pressure < 90 mmHg Contraindication to naso-gastric tube's insertion

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
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: PSV-ET 25<br>Pressure support ventilation with expiratory trigger set at 25 %. | Other: Expiratory trigger (ET)<br>* Varying the cycling criterion according to the percentage of peak inspiratory flow<br>|
| Active Comparator: PSV-ET 50<br>Pressure support ventilation with expiratory cycling set at 50 %. | Other: Expiratory trigger (ET)<br>* Varying the cycling criterion according to the percentage of peak inspiratory flow<br>|
| Experimental: NAVA<br>NAVA level is adjusted to achieve similar peak inspiratory pressure levels than during PSV. | Device: NAVA<br>* Assisted mechanical ventilation according to the electrical activity of the diaphragm recorded with a 16-FR naso-gastric tube mounted with EMG electrodes<br>* Other names: Neurally Adjusted Ventilatory Assist;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inspiratory muscle workload as reflected by the diaphragmatic Pressure Time Product (PTPdi) |  | 5 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ineffective inspiratory effort |  | 5 minutes | 
| Dynamic intrinsic PEEP |  | 5 minutes | 
| Arterial blood gases |  | 20 minutes | 
| Trigger delay |  | 5 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Mechanical ventilation, Neurally adjusted ventilatory assist (NAVA), Acute respiratory failure, Chronic obstructive pulmonary disease, Weaning, Invasive mechanical ventilation, Positive Pressure support Ventilation