Ventilator system

A method of operating a ventilator system, wherein the ventilator system comprises:

• a nasal cannula configured for supplying a flow of air and/or oxygen to one or both nares of a user;
• an air and oxygen supplying apparatus configured to supply flows of air and oxygen to the nasal cannula;
• a mouthpiece configured to be received within the user's mouth, wherein the mouthpiece comprises:
• a passage for permitting a flow of gases through the mouthpiece between a first side of the passage configured to be inside the user's mouth and a second side of the passage configured to be outside the user's mouth;
• a passage adjustment component for selectively adjusting a flow area of the passage;
• and
• one or more sensors mounted on the mouthpiece, wherein the sensors comprise a pressure sensor configured to measure a pressure at the first side of the passage;
• and
• a controller configured to control the operation of the ventilator system, wherein the method comprises:
• determining a pressure measurement from the pressure sensor;
• and, based on the determined pressure measurement:
• controlling a flow rate and/or concentration of oxygen supplied through the nasal cannula;
• controlling a total flow rate of air and oxygen supplied through the nasal cannula;
• and
• controlling the flow area of the passage.