Patent ID: 8651105

Claim:
A method for delivering a flow of oxygen-containing gas to the airway of a spontaneously-breathing patient with obstructive sleep apnea, said method comprising: providing a tube to deliver a flow of oxygen-containing gas into a patient's airway without interfering with a patient's spontaneous respiration around the tube; detecting a physical property of a patient's respiratory cycle; and supplying a flow of oxygen-containing gas to augment the patient's spontaneous respiration, said flow varying over each inspiratory and expiratory phase of the respiratory cycle in a predetermined non-constant flow waveform synchronized with the respiratory cycle, said waveform including: (a) a positive flow accelerating at the onset of the patient's inspiratory phase at a flow rate sufficient to at least partially prevent obstruction of the upper airway during obstructive sleep apnea, thereby significantly mitigating the airway pressure the patient must generate during spontaneous breathing and reducing the patient's work of breathing; and (b) a positive flow during at least the early portion of the patient's expiratory phase at a flow rate sufficient to at least partially prevent obstruction of the upper airway during obstructive sleep apnea, thereby significantly mitigating the airway pressure the patient must generate during spontaneous breathing, reducing the patient's work of breathing, and washing carbon dioxide from the patient's airway.