Neurally Adjusted Ventilatory Assist (NAVA) Study in Adults With Acute Respiratory Failure

Study Overview
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Brief Summary
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The purpose of this study is to compare a specific mode of artificial ventilation (help from a breathing machine) with other modes. This specific mode is called Neurally Adjusted Ventilatory Assist (NAVA) and is different from other modes as it uses direct signals from the diaphragm (breathing muscle) to help patients breathe. The investigators believe that using these signals, NAVA can determine the exact timing for patients' spontaneous breathing effort and delivers the artificial breath at the same time (in synchrony) with their own breath. Other modes (breathing methods) may cause asynchrony between the patient and the ventilator while delivering artificial breaths because of the way they operate. Asyncrony between patient and ventilator is a risk factor for increasing the length of artificial ventilation and number of related complications. The investigators would like to find out if NAVA performs better in establishing synchrony between patient and ventilator and as a result decreasing time for artificial ventilation and increasing better outcomes.

Detailed Description
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Study Goal To compare the ability of NAVA vs. conventional lung protective ventilation in a multicenter, unblinded, randomized, controlled fashion to provide invasive ventilatory support during acute respiratory failure in adults who are expected to require ventilatory support for greater than 72 hours. Hypothesis It is hypothesized that the use of NAVA compared to conventional lung protective ventilation will result in a decrease in the number of days of mechanical ventilation. It is further hypothesized that NAVA compared to conventional lung protective ventilation will result in a decrease in the length of weaning, the length of ICU and hospital stay, and mortality. Primary Outcome • Number of invasive ventilator free days. Secondary Outcome Mortality Length of Invasive Ventilation in survivors Length of ICU and hospital stay Incidence of barotrauma (defined as the presence of any extra-pulmonary air that was not present at study enrollment). Ventilator associated pneumonia (development of a pneumonia 48 hrs after entry into the study). Development of ARDS (after enrollment into the study; defined as a rapid onset, a P/F<200 mmHg, and bilateral pulmonary infiltrates that are not of cardiac origin).

Official Title
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A Comparative, Multicenter, Randomized, Controlled Study of Neurally Adjusted Ventilatory Assist (NAVA) vs. Conventional Lung Protective Ventilation in Patients With Acute Respiratory Failure

Conditions
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Acute Respiratory Failure

Intervention / Treatment
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* Other: NAVA ventilation
* Other: Conventional Lung Protective Ventilation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age greater than or equal to 18 years Hypoxemic or hypercapnic acute respiratory failure Intubation and mechanical ventilation Anticipated mechanical ventilation equal or longer than 72 hrs Mechanically ventilated less or equal to 5 days Able to spontaneously trigger the ventilator Exclusion Criteria: moderate-to-severe acute respiratory distress syndrome Post-operative patient's normally requiring a short course of mechanical ventilation (for example most cardiac surgical patients) Unable to spontaneously breathe Need to provide controlled ventilation Poor short term prognosis (defined as a high risk of death in the next 3 months) Neuromuscular or neurologic disease Age < 18 years Patients with major esophageal, gastric and oral surgery Acute brain injury or elevated intracranial pressure (> 18 mmHg) Severe cardiac disease: New York Heart Association class 3 or 4 or acute coronary syndrome or persistent ventricular tachyarrhythmias. Pregnancy, must be confirmed by laboratory analysis.

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Conventional Lung Protective Ventilation<br>In this group, patients will be ventilated in either volume A/C, pressure A/C, pressure support, pressure regulated volume control or volume support based on the discretion of the medical team with TV 4-8 ml/kg PBW range and PP or pressure (control or support) level <30 cmH2O. | Other: Conventional Lung Protective Ventilation<br>* conventional protective mechanical ventilation<br>|
| Other: NAVA Ventilation Group<br>In the NAVA group, NAVA level will be set initially at zero, then the maximum Edi will be determined as the average level over the next 3 to 5 breaths without ventilatory support or PEEP. The actual NAVA level will then be titrated by the clinician to achieve the following: 1) an Edi equal to approximately 50% of the maximum Edi, 2) an average tidal volume of between 4 to 8 ml/kg predicted body weight (PBW), and 3) an average respiratory rate between about 15 and 40 per minute. In addition, the trigger sensitivity should be set as sensitive as possible without causing auto-triggering and the maximum pressure limit in NAVA should be set at 40 cm H2O. | Other: NAVA ventilation<br>* Neurally adjusted ventilatory assist<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of invasive ventilator free days. | Number of days without mechanical ventilation, within the first 28 days of the study. | 28 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total length of mechanical ventilation in survivors (invasive plus noninvasive) | Total number of days of mechanical ventilation in ICU survivors. | 90 days | 
| ICU and hospital Mortality | Mortality during patient stay in the ICU and after being discharged from ICU | 90 days | 
| Incidence of barotrauma | Number of diagnosed pneumothorax | 60 Days | 
| Ventilator associated pneumonia | Number of diagnosed Ventilator Associated Pneumonia | 60 Days | 
| Development of Acute respiratory distress syndrome (ARDS) | Number of patients developing ARDS | 60 Days | 
| Length of ICU stay | Total number of days of ICU stay. | 90 Days | 
| Length of hospital stay | Total number of days of Hospital stay. | 90 Days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Acute Respiratory Failure, Mechanical Ventilation, NAVA, Lung protective ventilation, invasive ventilation, noninvasive ventilation