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

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

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 %).

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