16th February 2025

A 56-year-old man with a BMI of 47 attends the emergency department with two days of cough and worsening breathlessness.

A 56-year-old man with a BMI of 47 attends the emergency department with two days of cough and worsening breathlessness. He has known obesity hypoventilation syndrome and uses non-invasive ventilation at home.

His chest X-ray shows a new right-sided consolidation. He has been treated with antibiotics and started on non-invasive bilevel positive airway pressure (BiPAP).

The NIV device displays the following: FᵢO2 0.3, IPAP (inspiratory positive airway pressure) 8 cmH₂O, EPAP (expiratory positive airway pressure) 4 cmH₂O, tidal volume 255 ml, respiratory rate 27, leak 11 ml.

Arterial blood gas: pH 7.27, pCO₂ 8.2k Pa, pO₂ 8.7 kPa, HCO₃ 33 mmol/L, oxygen saturation 91%. 

What should the next step in management be?

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