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

Mass General Brigham

Status: Completed

Conditions: Acute Respiratory Failure

Treatments: Other: Conventional Lung Protective Ventilation; Other: NAVA ventilation

Study type: Interventional

Funder types: Other

Identifiers

NCT01730794

2012P002419

Details and patient eligibility

About

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.

Full description

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).

Enrollment: 306 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

---

306 participants in 2 patient groups

Conventional Lung Protective Ventilation

Other group

Description:

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.

Treatment:

Other: Conventional Lung Protective Ventilation

NAVA Ventilation Group

Other group

Description:

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.

Treatment:

Other: NAVA ventilation