27th August 2023

A 60-year-old man with a known history of severe asthma presents with increasing shortness of breath

A 60-year-old man with a known history of severe asthma presents with increasing shortness of breath. His respiratory rate is 36 breaths per minute, and he appears cyanotic. Arterial blood gas shows severe hypoxia and hypercapnia. His consciousness level deteriorates rapidly, and he becomes apnoeic with a pulse.

What is the first step in management?