Systems and methods for reducing co2 rebreathing from a positive airway pressure machine

A method for reducing CO2 rebreathing from a positive airway pressure machine including a pressure generator, a mask configured for placement over a patient's face, a conduit operably connecting the pressure generator to the mask, and an exhaust port, the method comprising:

• providing pressure into the patient's airway through the conduit and mask over a treatment period that includes a plurality of inhalation periods and a plurality of exhalation periods;
• measuring a volume of the patient's exhalation;
• and
• adjusting the pressure provided at an end portion of an exhalation period such that none of the patient's exhalation is present in the conduit at a beginning of an inhalation period.

A method for reducing CO2 rebreathing from a positive airway pressure machine including a pressure generator, a mask configured for placement over a patient's face, a conduit operably connecting the pressure generator to the mask, and an exhaust port, the method comprising:

• measuring a volume of the patient's exhalation;
• providing pressure into the patient's airway through the conduit and mask over a treatment period that includes a plurality of inhalation periods and a plurality of exhalation periods, wherein, during a first exhalation period, the pressure is provided at an initial pressure configured such that none of the patient's exhalation travels into the conduit;
• decreasing the pressure provided during successive exhalation periods by a predetermined amount until a portion of the patient's exhalation travels into the conduit;
• and
• increasing the pressure to the last pressure when none of the patient's exhalation traveled into the conduit.