16th February 2025

A 45-year-old woman attends the respiratory clinic with a long history of breathlessness and fatigue.

A 45-year-old woman attends the respiratory clinic with a long history of breathlessness and fatigue. Her wife has noted she stops breathing frequently throughout the night and then gasps for air. She has a thick neck and a BMI of 44. She has never smoked.

Spirometry: FEV1 49% predicted, FVC 52% predicted, FEV1/FVC ratio 0.85.

Arterial blood gas on room air: pH 7.37, pCO₂ 7.9 kPa, pO₂ 10.1 kPa, HCO₃ 35 mmol/L, oxygen saturation 90%.

After lifestyle advice has been given, what is the next most appropriate intervention?

Select the SINGLE most appropriate option from the list below. Select ONE option only.