Respiratory gas humidifier

• US 10,639,446 B2
• Filed: 10/29/2018
• Issued: 05/05/2020
• Est. Priority Date: 09/03/2014
• Status: Active Grant

• Current Assignee: Fisher & Paykel Healthcare Limited
• Original Assignee: Fisher & Paykel Healthcare Limited
• Inventors: Yatsevich, Igor Olegovich, Partington, Andrew John, Alami, Nordyn
• Primary Examiner(s): Hopkins, Robert A
• Application Number:
  US16/173,863
• Publication Number:
  US 20190167938A1
• Time in Patent Office: 554 Days
• Field of Search: 261142, 261 76, 261 782, 2611191, 2611211, 261DIG 65
• CPC Class Codes: A61M 16/0066 Blowers or centrifugal pumps
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/0808 Condensation traps
• CPC Class Codes: A61M 16/0875 Connecting tubes
• CPC Class Codes: A61M 16/1085 after being humidified or mixed with a beneficial agent
• CPC Class Codes: A61M 16/109 the humidifying liquid or the beneficial agent
• CPC Class Codes: A61M 16/1095 in the connecting tubes
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/161 with means for measuring the humidity
• CPC Class Codes: A61M 16/202 electrically actuated
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/003 with a flowmeter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2205/3653 by Joule effect, i.e. electric resistance
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 2230/04 Heartbeat characteristics, e.g. ECG, blood pressure modulation
• CPC Class Codes: A61M 2230/10 Electroencephalographic signals
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 2230/202 partial carbon oxide pressure, e.g. partial dioxide pressure (P-CO2)
• CPC Class Codes: A61M 2230/205 : partial oxygen pressure (P-O2)
• CPC Class Codes: A61M 2230/432 : partial CO2 pressure (P-CO2)
• CPC Class Codes: A61M 2230/435 : partial O2 pressure (P-O2)
• CPC Class Codes: B01F 2035/99 : Heating
• CPC Class Codes: B01F 2101/55 : Mixing liquid air humidifiers with air
• CPC Class Codes: B01F 23/21 : by introducing liquids into gaseous media
• CPC Class Codes: B01F 35/90 : Heating or cooling systems
• CPC Class Codes: F24F 3/14 : by humidification; by dehumidification

Abstract

A gas humidifier can have a gas channel comprising an inlet and an outlet. A portion of the gas channel can have a region having a reduction in cross-sectional area relative to the portions of the gas channel outside of the region. A water conduit can extend from the region to a water reservoir. A heating element can heat water entering the region from the water conduit. Water vaporized using the heating element can join the flow of gases passing through the gas channel in use.

Claims

1. A gas humidifier, comprising:

an air flow channel;

a liquid reservoir configured to hold a volume of liquid, the air flow channel separate from an air space above the volume of liquid in the reservoir;

a heater configured to heat a heated portion of the air flow channel;

a liquid distributor configured to distribute liquid transferred from the reservoir to the air flow channel over a surface to be heated by the heater, the heater configured to vaporize at least a portion of the distributed liquid to humidify gases flowing through the air flow channel; and

a collector positioned downstream of the heater, the collector configured to collect excess liquid in the air flow channel.

2. The gas humidifier of claim 1, wherein the collector is configured to return the excess liquid to the reservoir.

3. The gas humidifier of claim 1, wherein the collector comprises an aperture in a wall of the air flow channel.

4. The gas humidifier of claim 3, wherein the aperture is positioned in a local-recessed portion of the air flow channel.

5. The gas humidifier of claim 3, wherein a portion of the air flow channel defining an upstream-facing edge of the aperture is angled towards the reservoir.

6. The gas humidifier of claim 3, wherein collector comprises a conduit extending from the aperture to the reservoir.

7. The gas humidifier of claim 6, wherein collector comprises a suction mechanism configured to suction excess liquid into the conduit.

8. The gas humidifier of claim 7, wherein the suction mechanism comprises a secondary gas channel in fluid communication with the conduit configured to create a low pressure area to suction the excess liquid into the conduit.

9. The gas humidifier of claim 7, wherein the suction mechanism comprises a second aperture downstream of the aperture.

10. The gas humidifier of claim 9, wherein the air flow channel comprises a baffle or ridge positioned between the aperture and the second aperture.

11. The gas humidifier of claim 3, wherein the air flow channel comprises a baffle or ridge positioned downstream of the aperture.

12. The gas humidifier of claim 1, wherein the gas humidifier is configured to couple to a heated tube configured to delivery gases to a patient.

13. The gas humidifier of claim 3, wherein the liquid distributor comprises microstructures, a fibrous material, and/or a sorbent material.

14. The gas humidifier of claim 3, wherein the liquid distributor comprises a physical or chemical surface treatment configured to provide hydrophilic or wicking properties.

15. A method of removing excess liquid from a gas flow channel of a humidifier, the humidifier comprising a reservoir configured to hold a volume of liquid, the gas flow channel separate from an air space above the volume of liquid in the reservoir, the method comprising:

delivering liquid from a liquid reservoir to the gas flow channel;

vaporizing at least a portion of the liquid to humidify gases flowing through the gas flow channel; and

collecting excess liquid in the gas flow channel.

16. The method of claim 15, further comprising passing the excess liquid from the air flow channel upstream of an outlet of the humidifier.

17. The method of claim 15, further comprising returning the excess liquid to the reservoir.

18. The method of claim 15, wherein the collecting the excess liquid comprises suctioning the excess liquid from the gas flow channel via a low pressure region.

19. The method of claim 18, further comprising funneling at least a portion of the gases flowing through the gas flow channel to create the low pressure region.

20. The method of claim 15, further comprising distributing liquid delivered from the liquid reservoir to the gas flow channel over a surface to be heated by a heater in the gas flow channel.