diagnostic tests for COPD (chronic obstructive pulmonary disease)-OSAHS (obstructive sleep apnoea/hypopnoea syndrome) overlap syndrome

Last edited 09/2021 and last reviewed 10/2021

Diagnostic tests for COPD (chronic obstructive pulmonary disease)-OSAHS (obstructive sleep apnoea/hypopnoea syndrome) overlap syndrome

Diagnosing ventilatory failure

• measure arterial or arterialised capillary blood gas when the person with suspected COPD-OSAHS overlap syndrome is awake, to assess for ventilatory failure
• do not delay treatment for acute ventilatory failure to carry out further investigations for COPD-OSAHS overlap syndrome.

Diagnosing OSAHS or nocturnal hypoventilation in people with suspected COPD-OSAHS overlap syndrome

• offer respiratory polygraphy, either in hospital or at home, to diagnose OSAHS in people with suspected COPD–OSAHS overlap syndrome
• consider adding transcutaneous carbon dioxide (CO2) monitoring during sleep to respiratory polygraphy to provide additional information to guide treatment
• do not use oximetry alone to diagnose OSAHS or nocturnal hypoventilation in people with suspected COPD–OSAHS overlap syndrome

Reference:

• NICE (August 2021). Obstructive sleep apnoea/hypopnoea syndrome and obesity hypoventilation syndrome in over 16s