Medical gas humidification system

• US 20040254524A1
• Filed: 06/12/2003
• Published: 12/16/2004
• Est. Priority Date: 06/12/2003
• Status: Active Grant

• Current Assignee: Lexion Medical LLC
• Original Assignee: Lexion Medical LLC
• Inventors: Burban, John H., Zia, Majid, Ott, Douglas E., Spearman, Michael
• Granted Patent: US 7,476,212 B2
• Time in Patent Office: Days
• US Class Current: 604/26
• CPC Class Codes: A61M 13/003 Blowing gases other than for carrying powders, e.g. for inflating, dilating or rinsing
• CPC Class Codes: A61M 16/107 in the inspiratory path
• CPC Class Codes: A61M 16/109 the humidifying liquid or the beneficial agent
• CPC Class Codes: A61M 16/142 with semi-permeable walls separating the liquid from the respiratory gas
• CPC Class Codes: A61M 16/161 with means for measuring the humidity
• CPC Class Codes: A61M 16/162 Water-reservoir filling system, e.g. automatic

Abstract

An apparatus and method for on-the-go humidifying an insufflation gas through water vapor transfer from a liquid to the insufflation gas through a barrier separating the gas from the liquid to enable the gas in a normally trauma inducing state to be brought to a conditioned state. If the gas is at an improper insufflation temperature the temperature of the gas can be brought to the proper insufflation temperature at the same time the gas is humidified through heat transfer through the barrier.

Claims

1. A system for conditioning a medical gas to bring the medical gas to a state when delivered to a body cavity prevents or inhibits further trauma comprising:

a source of medical gas;

an elongated coaxial tube, said elongated coaxial tube having an internal medical gas conduit and an exterior semi circular fluid conduit, said medical gas conduit having a sidewall comprised of a diffusion membrane, said medical gas conduit having an outlet for discharging a heated and humidified medical gas therefrom;

a fluid inlet in said semi-circular fluid conduit;

a fluid outlet in said semi-circular fluid conduit to permit circulation of the fluid through said semi-annular fluid conduit;

a medical gas temperature sensor, said medical gas temperature located in said internal medical conduit to monitor the temperature of the medical gas discharging from the medical gas outlet;

a fluid heater;

a pump for circulation of a fluid through the semi-annular fluid conduit so that when the medical gas is delivered through said internal medical gas conduit the fluid circulating through said semi-annular fluid simultaneously raise both the temperature of the medical gas and the humidity of the medical gas to a body deliverable state.

2. The system of claim 1 including a control module for regulating the flow of medical gas through the medical gas conduit.

3. The system of claim 1 including a filter for removing contaminants from the medical gas before flowing the medical gas into the medical gas conduit.

4. The system of claim 1 including an entry device for directing the medical gas into the body cavity.

5. The system of claim 1 including a control module for monitoring the temperature of the gas and for controlling the flow of fluid flowing through the fluid passage to thereby control the temperature of the medical gas discharging from the elongated tube.

6. The system of claim 1 wherein the fluid system is a closed system.

7. A method of delivering a medical gas in a conditioned state to a body cavity to avoid or inhibit body trauma comprising;

directing a medical gas into a body cavity through a lumen located on a first side of a barrier permeable to water vapor but impermeable to liquid water to thereby transfer water vapor through the barrier and into the medical gas so that when the medical gas discharges therefrom the humidity of the medical gas is in a conditioned state for insufflation.

8. The method of claim 7 wherein the temperature of the medical gas deliverable to the body cavity is maintained at about 37°

centigrade.

9. The method of claim 7 wherein a temperature of the medical gas discharging therefrom is monitored and the heat transfer from the fluid to the medical gas is controlled to maintain the medical gas at a constant temperature.

10. The method of claim 7 wherein the relative humidity of the gas is maintained in excess of 50%.

11. The method of claim 7 wherein the relative humidity of the gas is maintained in excess of 96%.

12. The method of claim 7 wherein a heated fluid flows through a lumen located on a first side of the barrier to thereby transfer heat to the medical gas through the barrier so that when the medical gas discharges therefrom the humidity and the temperature of the medical gas are in a conditioned state.

13. An apparatus for delivering medical gas in a conditioned state to a body cavity comprising;

a medical gas enclosure;

a barrier permeable to water vapor but impermeable to liquid water, said barrier forming at least a part of the medical gas enclosure, said barrier having a first side proximate a supply of water for transfer of water vapor from the water to a medical gas on the opposite side of the barrier to thereby bring the medical gas to a conditioned state for insufflation.

14. The apparatus of claim 13 wherein the water is heated to an insufflation temperature to bring the medical gas to a body deliverable state through conductive heat transfer through the barrier.

15. The apparatus of claim 14 wherein the barrier comprises a tubular member and the first side comprises a fluid passage internal to the tubular member and the opposite side comprises a fluid passage external to the tubular member.

16. The apparatus of claim 15 wherein the tubular member has a circular cross section.

17. The apparatus of claim 13 including a pair of longitudinal extending radial fins extending from an exterior surface of the barrier to an interior surface of a fluid conduit to provide a first fluid passage for fluid to flow in a first direction away from a heat source and a second fluid passage for fluid to flow in a second direction back to the heat source.

18. An apparatus for delivering medical gas in a conditioned state to a body cavity comprising;

a medical gas conduit;

a liquid gas separation barrier, said liquid gas separation barrier having a first side for contacting a fluid and a second side for contacting a medical gas, said liquid gas separation barrier permitting passage of water vapor into the medical gas through the liquid gas separation barrier while at the same time preventing passage of liquid therethrough to thereby bring the medical gas to a conditioned humidification state for deliver to a patient.

19. The apparatus of claim 18 wherein the liquid gas separation barrier comprises a diffusion membrane.

20. The apparatus of claim 18 wherein the liquid gas separation barrier comprises a sheet of material extending between a liquid chamber and a medical gas chamber.

21. The apparatus of claim 18 wherein the liquid gas separation barrier comprises a hydrophobic material.

22. The apparatus of claim 18 wherein the liquid gas separation barrier comprises a sidewall of a cylindrical tube.

23. The apparatus of claim 22 wherein the liquid gas separation barrier comprises a material selected from the group consisting of polyvinyl alcohol, cellulose, cellulose derivatives, nylon, polyester, polycarbonate, polysulfone, polyethersulfone, polyimide, silicone and polyurethane.

24. The apparatus of claim 22 including a chamber for receiving a source of water with a heater located in said chamber for heating the water.

25. The apparatus of claim 24 wherein the chamber includes a pouch punctureable end on a fluid conduit.

26. The apparatus of claim 25 including a pouch with a punctureable covering for placing in the chamber.

27. The apparatus of claim 22 wherein the liquid gas separation barrier comprises a cylindrical tube of hydrophobic material.

28. The apparatus of claim 22 wherein the liquid gas separation barrier has pores less than 0.2 microns in diameter to prevent passage of bacteria through the liquid gas separation barrier.

29. The apparatus of claim 22 wherein the water is in non-dispersive contact with the liquid gas separation barrier.

30. The apparatus of claim 19 wherein the diffusion membrane is a nonporous membrane.

31. The apparatus of claim 19 wherein the diffusion membrane is a hydrophobic membrane.

32. The apparatus of claim 31 wherein the hydrophobic membrane is selected from the group consisting of polyolefin, fluorinated polymers such as tetrafluoroethylene or fluorinated ethylene-propylene, polyetherimide, polysulfone and silicone.

33. An apparatus for delivering medical gas in a conditioned state to a body cavity comprising;

a medical gas;

a chamber for holding the medical gas;

a source of water, said source of water located external the chamber for holding the medical gas;

a wick, said wick extending into said source of water and into said chamber to permit the wicking of water into the medical gas located therein.

34. The apparatus of claim 33 including an inlet to the chamber for introducing an unhumidified medical gas therein and an outlet for delivering a humidified medical gas therefrom.

35. The apparatus of claim 33 wherein the wick comprises a flexible fabric.

36. The apparatus of claim 33 wherein the wick is located proximate a body cavity to be insufflated so that any water condensation can be absorbed by the wick to thereby prevent ingress into the body cavity of the patient.

37. The apparatus of claim 33 including:

a liquid gas separation barrier located upstream of said wick, said liquid gas separation barrier having a first side for contacting a fluid and a second side for contacting a medical gas, said liquid gas separation barrier permitting passage of water vapor into the medical gas through the liquid gas separation barrier while at the same time preventing passage of liquid therethrough to thereby bring the medical gas to a conditioned state for deliver to a patient.