Accurate pressure measurement with non-invasive ventilation nasal pillows

A method of correcting a sensed patient airway pressure Psense in a patient ventilation interface, the method comprising:

• providing a patient ventilation interface including a throat body defining a venturi throat that is open to ambient air, a nasal pillow disposed around the venturi throat to define a plenum between the venturi throat and the nasal pillow, and a jet nozzle arranged to output ventilation gas into the venturi throat;
• sensing a patient airway pressure Psense in a pressure sensing tube having a pressure sensing port positioned to be in fluid communication with the plenum;
• and
• correcting for an expected error in the sensed patient airway pressure Psense by applying a correction factor Pdelta indexed by the sensed patient airway pressure Psense.

A method of non-invasive ventilation, the method comprising:

• providing a patient ventilation interface including a throat body defining a venturi throat that is open to ambient air, a nasal pillow disposed around the venturi throat to define a plenum between the venturi throat and the nasal pillow, and a jet nozzle arranged to output ventilation gas into the venturi throat;
• sensing a patient airway pressure Psense in a pressure sensing tube having a pressure sensing port positioned to be in fluid communication with the plenum;
• and
• controlling delivery of the ventilation gas output by the jet nozzle in response to a patient airway pressure Psense sensed by the pressure sensor.