Impact of the Assisted Ventilation Mode on Diaphragm Efficiency in Critically Ill Patients (NAVA_PSV)

University of Bari

Status and phase

Completed

Phase 2

Conditions

Respiratory Insufficiency

Treatments

Device: Pressure Support ventilation

Device: Neurally Adjusted Ventilatory Assist

Study type

Interventional

Funder types

Other

Identifiers

NCT02473172

NAVA_PSV

Details and patient eligibility

About

This study evaluates the impact of the assisted mode of mechanical ventilation on diaphragm efficiency in mechanically ventilated critically ill patients. Participants will be randomized to the neurally adjusted ventilatory assist (NAVA) mode or to the pressure support ventilation (PSV) mode.

Full description

During mechanical ventilation the ventilator applies positive pressure to the respiratory system. Often in the acute phase of critical illness patients are ventilated in the control mode (CMV), where the patient is completely passive. This quickly (within 48 hours) has been shown to induce diaphragm atrophy and dysfunction (Levine et al New England Journal of Medicine, 200; 358:1327-35). To preserve diaphragm function, guidelines suggest to shift as soon as possible to the assisted mode (the ventilator applies positive pressure to assist spontaneous inspiratory effort). The synchrony between patient and ventilator is critical in this context. PSV is the classical assisted mode and applies a constant pressure whatever the patient effort. NAVA is a newer mode based on the diaphragm electrical activity (EAdi) measurement. It assist patient effort proportionally to the EAdi and hence to patient's effort. The investigator hypothesis is that NAVA would improve diaphragm efficiency more efficiently than PSV.

Enrollment

38 patients

Sex

All

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

older than 18 years
oro-tracheally or naso-tracheally intubate
had been ventilated for acute respiratory failure in control mechanical ventilation for at least 72 hours consecutively
candidate to assisted ventilation
Hemodynamically stable without vasopressor or inotropes (excluding a dobutamine and dopamine infusion lower than 5 gamma/Kg/min and a 3 gamma /Kg/min, respectively
normothermia

Exclusion criteria

Neurological or neuromuscular pathologies
phrenic nerve dysfunction
contraindications to the insertion of a nasogastric tube (for example recent upper gastrointestinal surgery, esophageal varices).