The study was terminated due to recruitment slower than anticipated

This study will use a modified version of a positive airway pressure device to supply air to the participant, while undergoing supervised polysomnography. Positive airway pressures are typically applied to many patients with hypoventilation, in this study these pressures will be titrated by a qualified sleep technician. During the night these pressures will be altered to optimise comfort.

Inclusion Criteria:

• Aged 18+
• Patients diagnosed with obesity hypoventilation syndrome (OHS) and/or obstructive sleep apnea (OSA) by a practicing sleep or respiratory physician, requiring positive airway pressure (PAP) therapy

Exclusion Criteria:

• Recent cardiac or respiratory arrest
• Gastro intestinal bleeding, ileus or recent gastrointestinal surgery
• Coma, decreased level of consciousness or agitation
• Anatomical or subjective difficulty with airway access e.g. facial surgery, trauma, vomiting upper airway obstruction
• Cerebrospinal fluid leak, abnormalities of the cribiform plate or prior history of head trauma.