NIV-NAVA vs NIV-PS/PC in Respiratory Insufficiency

This study evaluates the difference between Non Invasive Ventilation with Neurally Adjusted Ventilatory Assist (NIV-NAVA) and Conventional Non Invasive Ventilation with Pressure Support (PS) or Pressure Control (PC). All the patients are ventilated in each mode for 4 hours. Afterwards they will be subjected to a semi-structured interview where they will be asked to compare the two modes. The hypothesis is that NIV-NAVA will correct patients power of Hydrogen (pH), PaCO2 og PaO2 more quickly than NIV-PS and NIV-NAVA is more comfortable for the patients.

Neurally Adjusted Ventilatory Assist (NAVA) is a ventilation mode where the diaphragm is controlling the amount of ventilatory assistance proportionally through a nasogastric tube containing electrodes which are sending the electrical activities of the diaphragm (Eadi) to the ventilator. Whereas Conventional ventilation modes like Pressure support or Pressure Control are dependent on the pressure drop or flow reversal to initiate assist delivered to the patient. This is last step of the signal chain leading to inhalation and is subject to disturbances such as intrinsic positive expiratory end pressure (PEEP), hyperinflation and leakage.