High flow humidifier for delivering heated and humidified breathing gases

• US 7,302,949 B2
• Filed: 12/03/2004
• Issued: 12/04/2007
• Est. Priority Date: 12/03/2004
• Status: Active Grant

• Current Assignee: Smiths Medical ASD, Inc. (Smiths Group International Holdings Ltd.)
• Original Assignee: Smiths Medical ASD, Inc. (Smiths Group International Holdings Ltd.)
• Inventors: Richards, Fredrick M., King, Gregory S., Pelerossi, Richard K., Niles, Rex A.
• Primary Examiner(s): Yu; Justine R.
• Assistant Examiner(s): Ali; Shumaya B.
• Application Number:
  US11/003,527
• Publication Number:
  US 20060118111A1
• Time in Patent Office: 1,096 Days
• Field of Search: 128/200.14, 128/200.16, 128/203.15, 128/203.16, 128/203.17, 128/204.18, 128/204.21, 128/204.22, 128/204.24, 128/205.12, 128/205.24, 128/205.27, 128/206.22, 128/200.21, 128/203.26, 128/203.27, 128/203.25, 239/135, 239/136, 239/340, 239/346, 239/10, 239/13, 239/128, 239/138, 239/125, 239/303, 239/310, 239/314, 239/317, 239/378, 239/548, 261/76, 261/78.2, 261/141, 261/142, 261/DIG.65, 222/56
• US Class Current: 128/200.14
• CPC Class Codes: A61M 16/0672 Nasal cannula assemblies for oxygen therapy
• CPC Class Codes: A61M 16/0808 Condensation traps
• CPC Class Codes: A61M 16/109 the humidifying liquid or the beneficial agent
• CPC Class Codes: A61M 16/127 by Venturi effect, i.e. entrainment mixers
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/162 Water-reservoir filling system, e.g. automatic

Abstract

An improved humidifier which may be used with a nasal cannula for high-flow respiratory gas therapy wherein a sterilized liquid is drawn from a sterilized liquid container by a high-flow driving gas passing adjacent to an aspirator tube orifice through which the sterilized liquid is drawn into contact with the driving gas for fracturing the liquid into a mist which is warmed and delivered to the patient or user, and the driving gas is also passed adjacent a condensate return orifice which draws any condensate formed in the humidified respiratory gas delivery system away from the cannula and back into the system for re-use.

Claims

1. A humidifier for providing warm moist respiratory gases, comprising;

a respiratory gas heating chamber having a closed top, enclosing sides, and an open bottom adapted to receive for coupling thereto a container adapted to contain a liquid to be aerosolized into a vapor;

a vapor-forming flow-control chamber in fluid communication with said respiratory gas heating chamber for forming an aerosolized vapor from liquid in fluid communication therewith;

nozzle means in fluid communication with said vapor-forming flow-control chamber for creating an aerosolized vapor from respiratory gas and the liquid in fluid communication with said vapor-forming flow-control chamber;

a first orifice positioned in fluid communication with said nozzle means such that the flow of respiratory gas from said nozzle means will create a reduced pressure across said first orifice for withdrawing a condensate fluid therethrough;

a second orifice positioned in fluid communication with said nozzle means and spaced from said first orifice such that the flow of respiratory gas from said nozzle means will create a reduced pressure across said second orifice for withdrawing therethrough liquid contained in a container coupled to said respiratory gas heating chamber;

heating means for warming the aerosolized vapor created by said nozzle means;

a discharge port in fluid communication with said vapor-forming fluid-control chamber for delivering the warm aerosolized vapor to a nasal cannula for inhalation by a user; and

condensate conduit means in fluid communication with said first orifice for withdrawing therethrough condensate formed by the cooling of the warm aerosolized vapor during delivery thereof to the nasal cannula.

2. The apparatus of claim 1 wherein said heating means comprises a surface contact heater.

3. A humidifier for use with a heater for providing warm moist respiratory gases, comprising;

a respiratory gas heating chamber having a closed top, enclosing sides, and an open bottom adapted to receive for coupling thereto a container adapted to contain a liquid to be aerosolized into a vapor and adapted to receive a heater for warming the aerosolized vapor;

a vapor-forming flow-control chamber in fluid communication with said respiratory gas heating chamber for forming an aerosolized vapor from liquid in fluid communication therewith;

nozzle means in fluid communication with said vapor-forming flow-control chamber for creating an aerosolized vapor from respiratory gas and the liquid in fluid communication with said vapor-forming flow-control chamber;

a first orifice positioned in fluid communication with said nozzle means such that the flow of respiratory gas from said nozzle means will create a reduced pressure across said first orifice for withdrawing a condensate fluid therethrough;

a second orifice positioned in fluid communication with said nozzle means and spaced from said first orifice such that the flow of respiratory gas from said nozzle means will create a reduced pressure across said second orifice for withdrawing therethrough liquid contained in a container coupled to said respiratory gas heating chamber;

a discharge port in fluid communication with said vapor-forming fluid-control chamber for delivering the warm aerosolized vapor to a nasal cannula for inhalation by a user; and

condensate conduit means in fluid communication with said first orifice for withdrawing therethrough condensate formed by the cooling of the warm aerosolized vapor during delivery thereof to the nasal cannula.

4. The apparatus of claim 3 wherein said respiratory gas heating chamber includes a heating plate of thermally conductive material for transferring heat energy to the aerosolized vapor.

5. The apparatus of claim 3 further including a container for containing sterile water, said container adapted to be threadingly engaged with said respiratory gas heating chamber.

6. The apparatus of claim 3 wherein said respiratory gas heating chamber bottom adapted to receive a container for containing a liquid to be aerosolized into a vapor, has a downwardly-shaped portion for engaging the open top of a container when the container is threadingly engaged with said respiratory gas heating chamber.

7. The apparatus of claim 3 wherein said first orifice for withdrawing a condensate fluid therethrough is positioned in closer proximity to said nozzle means than is said second orifice for withdrawing liquid contained in a container coupled to said respiratory gas heating chamber.

8. The apparatus of claim 7 wherein said first orifice and said second orifice are spaced seriatim in fluid communication with said nozzle means.

9. The apparatus of claim 3 wherein said vapor-forming flow-control chamber includes a metering orifice means for metering the flow of condensate formed therein onto said heating plate.

10. The apparatus of claim 3 further including a nose cannula in fluid communication with said discharge port and said condensate communication means.

11. The apparatus of claim 3 wherein said discharge port is coupled to a discharge conduit for deliver of warm aerosolized vapor to the nose cannula.

12. The apparatus of claim 11 wherein said condensate conduit means is carried within said discharge conduit.

13. The apparatus of claim 11 further including a moisture-collection cannula connector in fluid communication with said discharge conduit and said condensate conduit means.

14. The apparatus of claim 13 further including a moisture collecting means carried within said moisture-collecting cannula connector for removing excess moisture from the warm aerosolized vapor and returning such excess moisture to said flow-control chamber.

15. The apparatus of claim 3 wherein said flow-control chamber includes an overflow outlet means in fluid communication with the container for directing excess condensate to the container.