Nasal cannula

• US 20030079749A1
• Filed: 10/25/2001
• Published: 05/01/2003
• Est. Priority Date: 10/25/2001
• Status: Active Grant

• Current Assignee: Innomed Technologies Incorporated (SunMed Group Holdings LLC)
• Original Assignee: Worldwide Medical Technologies, LLC
• Inventors: Lee, Jonathan, Strickland, Roger
• Granted Patent: US 6,679,265 B2
• Time in Patent Office: Days
• US Class Current: 128/203.22
• CPC Class Codes: A61M 16/0666 Nasal cannulas or tubing devices for improving normal breathing through the nose A61F5/08; nose filters A62B23/06; outside holding devices A61M25/02
• CPC Class Codes: A61M 16/0683 Holding devices therefor
• CPC Class Codes: A61M 16/0833 T- or Y-type connectors, e.g. Y-piece

Abstract

A nasal cannula for delivering air to a patient'"'"'s nares. Two delivery tubes are provided to supply air to a pair of nasal inserts each of which conform to the shape of the nare. Properly placed bleed ports reduce noise and reduce carbon dioxide retained in the system. The cannula is positioned on the face with the aid of a strap system.

Claims

1. A nasal cannula comprising:

first and second nasal inserts for insertion into a patient'"'"'s nares;

a left and right delivery tube coupled to both of said nasal inserts, whereby each nasal insert communicates with both the left delivery tube and right delivery tube;

a coupler located remote from said nasal inserts for coupling said cannula to a source of respiration gas.

2. The nasal cannula of claim 1 further comprising:

a tubular bleed port having an internal lumen;

said tubular bleed port located directly in line with said nasal insert for preferentially intercepting expired gas during an exhalation.

3. The nasal cannula of claim 2 wherein:

said tubular bleed ports are located and sized to reduce the carbon dioxide content of inspired air to a value below approximately 0.5% carbon dioxide.

4. The nasal cannula of claim 2 wherein:

said tubular bleed ports have a BDP/h1 ratio of between 0.1 and 0.5.

5. The nasal cannula of claim 1 wherein:

said nasal inserts have a compliant flange at their distal ends to conform to the nare of a patient.

6. The nasal cannula of claim 5 wherein:

the length of the nasal insert is sufficiently long to allow the insert to move in the nasal passage until the cross section area of the nare and the nasal insert match.

7. The device of claim 2 wherein:

said tubular bleed port has a diameter size (BPD) which determined by

(BPD) Bleed Port Diameter

$\text{(}\text{BPD}\text{) <br><br> <br><br>Bleed <br><br> <br><br>Port <br><br> <br><br>Diameter}=2<br><br>\sqrt{\frac{X*\mathrm{IDS}}{\mathrm{\pi <br><br>}*F}}.$

8. The device of claim 2 wherein:

said tubular bleed ports are two in number and they are spaced along the delivery tube having a separation distance (L) which is approximated by;

(L) bleed port separation distance is approximately

$\text{(}\text{L}\text{) <br><br> <br><br>bleed <br><br> <br><br>port <br><br> <br><br>separation <br><br> <br><br>distance <br><br> <br><br>is <br><br> <br><br>approximately}\approx <br><br>\frac{A*F}{X^2}.$