Target Volume in Noninvasive Positive Pressure Ventilation

Comparison of Two Noninvasive Positive Pressure Ventilation Devices Using Target Volume Modes in Obesity Hypoventilation Syndrome (OHS): A Pilot Randomized Crossover Controlled Trial

Patients with OHS are efficiently managed with long term home-based nocturnal noninvasive positive pressure ventilation (NIPPV). Several NIPPV devices offer the feature of automatically adjusting pressure support (and/or respiratory back-up rate) on the basis of a pre-determined "ideal tidal volume" or "ideal ventilation". However algorithms used to achieve these ideal targets are different among different commercialized devices and the relative efficacy from an algorithm compared to another remains unknown. The main objective is this study is to compare two commercialized NIPPV that have this option

RESMED Stellar-150 (IVAPS mode)versus PHILIPS-RESPIRONICS A30 (AVAPS-mode).

Inclusion Criteria:

• Patient with Obesity hypoventilation Syndrome (BMI≥ 30 kg/m2 and diurnal PaCO2 ≥ 45mmHg at diagnosis after exclusion of others causes of hypoventilation)
• 18 to 75 years old
• In stable state but treated by nocturnal NIPPV for more than 3 months and adherent to NIPPV (above 4h/night).

Exclusion Criteria:

• patient treated with additional long term Oxygen therapy
• Patient previously treated by AVAPS mode or IVAPS mode