Efficacy of Volume Ventilation in Patients With Acute Respiratory Failure at Risk of Obstructive Apneas or Obesity Hypoventilation

This study compares a volume targeted pressure support non-invasive ventilation with an automatic PEP regulation (AVAPS-AE mode) to a pressure support non-invasive ventilation (S/T mode) in patients with acute hypercapnic respiratory failure with acidosis. This study focuses on patients at risk of obstructive apneas or obesity-hypoventilation syndrom (BMI≥30 kg/m²). Half of participants (33 patients) will receive non invasive ventilation with AVAPS-AE mode, the other half will receive non-invasive ventilation with S/T mode.

So far, in respiratory intensive care units, the usual treatment of patients with acute hypercapnic respiratory failure with acidosis is non-invasive ventilation set with a pressure support mode (S/T or VS/AI mode depending on the ventilator manufacturer). AVAPS-AE mode is a volume targeted pressure support mode with an automatic PEP. With the forced oscillations method, the ventilator is able to detect the obstruction and the resistances of upper airways. It allows the ventilator to change its pressure settings to keep the targeted volume and avoid apneas and hypoventilation. That is why in patients with a BMI \> 30 kg/m², at risk of obesity hypoventilation syndrom or obstructive apneas, this ventilation mode may be interesting. AVAPS-AE has been evaluated in the home ventilation showing it is as efficient as S/T mode in controlling PaCO2. However it has never been compared to S/T mode in acute respiratory failure care.