Method and system with divided cannula having low oxygen flow rate and improved end-tidal co2 measurement

A nasal cannula comprising:

• an elongate face piece comprising first and second nares, and the first nare facilitates communication with a first nostril of a patient while the second nare facilitates communication with a second nostril of the patient;
• a septum dividing the face piece into first and second flow paths such that the first flow path communicates with the first nare and the second flow path communicates with the second nare;
• a leading end of the first nare being configured to form a fluid barrier within the first nostril of the patient to facilitate only supplying an insufflation gas, via the first flow path, to the patient and prevent exhaust any of exhaust gas, from the patient, through the first nostril of the patient;
• at least one opening being formed in a sidewall of the first nare, and the at least one opening in the first nare permits the insufflating gas to collect and accumulate temporarily in a nasal region closely surrounding and adjacent the first nare, and reenter into the first nare, through the at least one opening, and be inhaled by the patient during inhalation by the patient;
• a leading end of the second nare being configured to facilitate collection of some of the exhaust gas, from the patient, via the second flow path as well as exhausting a remainder of the exhaust gas, from the patient, out through the second nostril of the patient;
• and
• a first opening being formed in a first end of the face piece while a second opening being formed in the opposite second end of the face piece, an oxygen supply tube being connected to the first opening while an end-tidal CO2 detection tube being connected to the second opening, a second opposed end of the oxygen supply tube being connected to a source of an oxygen gas while a second opposed end of the end-tidal CO2 detection tube being connected to a carbon dioxide monitoring device.

A method of improving measurement of end tidal CO2 gas exhaled by a patient with a divided cannula which comprises an elongate face piece comprising first and second nares, and the first nare facilitates communication with a first nostril of the patient while the second nare facilitates communication with a second nostril of the patient;

• a septum dividing the face piece into first and second flow paths such that the first flow path communicating with the first nare and the first nostril and the second flow path communicating with the second nare and the second nostril;
• a leading end of the first nare being configured to form a fluid barrier within the first nostril of the patient to facilitate only supplying an insufflation gas, via the first flow path, to the patient and prevent exhausting any of exhaust gas, from the patient, through the first nostril of the patient;
• and a leading end of the second nare being configured to facilitate collecting some of the exhaust gas, from the patient, via the second flow path as well as exhausting a remainder of the exhaust gas, from the patient, out through a second nostril of the patient;
• the method comprising the steps of:
• dedicating the first nostril of the patient for solely supplying the insufflation gas to the patient and preventing exhausting any exhaust gas through the first nostril;
• and
• dedicating the second nostril of the patient for solely exhaling gas from the patient and sampling the end tidal CO2 gas, exhaled by the patient, via the second nare.