Partial vapor removal through exhaust port

• US 5,869,000 A
• Filed: 06/20/1997
• Issued: 02/09/1999
• Est. Priority Date: 06/20/1997
• Status: Expired due to Fees

• Current Assignee: Ethicon Incorporated (Johnson & Johnson)
• Original Assignee: Johnson & Johnson Medical Incorporated (Johnson & Johnson)
• Inventors: DeCato, Kevin Richard
• Primary Examiner(s): Thornton, Krisanne
• Application Number:
  US08/879,446
• Time in Patent Office: 599 Days
• Field of Search: 422/1, 422/21, 422/23, 422/28, 422/33, 422/186, 422/292, 422/294, 422/300, 422/305, 422/307, 422/906
• US Class Current: 422/33
• CPC Class Codes: A61L 2/14 Plasma, i.e. ionised gases
• CPC Class Codes: A61L 2/20 Gaseous substances, e.g. vapours
• CPC Class Codes: A61L 2/26 Accessories or devices or components used for biocidal treatment

Abstract

An apparatus and method for vapor sterilization of articles such as medical devices and instruments with lumens. The lumens are connected in a sterilization chamber to a conduit which leads to an exhaust flow restrictor, which exhausts to a vacuum pump. The exhaust flow restrictor has a bypass also which exhausts to the vacuum pump. The majority of the gas from the sterilization chamber flows through the bypass on the exhaust flow restrictor while only a portion of the gas flows through the lumen. Because most of the gas flows through the bypass rather than through the lumens, the sterilization chamber can be pumped down rapidly. The attached lumens are sterilized effectively in spite of the rapid pumpdown rate.

Claims

1. An apparatus for sterilizing the interior and exterior of a device with at least two open ends and a flow path therebetween, comprising:

(a) a sterilization chamber having an exhaust port;

(b) a source of liquid or vapor sterilant, adapted to provide said sterilant in said sterilization chamber;

(c) a vacuum source with a vacuum valve to create a sterilization vapor from said sterilant, a negative pressure differential at said exhaust port of said sterilization chamber and an exhaust flow path out of said chamber;

(d) a vapor exhaust flow restrictor having at least a first and a second flow path; and

(e) a gas and vapor flow conduit connecting one of said open ends of said device to the first flow path of the vapor exhaust flow restrictor,

wherein said vapor exhaust flow restrictor allows part of the sterilization vapor to flow through said flow path of said device, through said gas and vapor flow conduit, through said first flow path of said vapor exhaust flow restrictor, and thereafter out of said sterilization chamber through said vacuum valve and vacuum source and wherein the remainder of the sterilization vapor flows directly out of said sterilization chamber through the second flow path of said exhaust flow restrictor and through said vacuum valve and vacuum source without passing through said flow path of said device and said gas and vapor flow conduit.

2. The apparatus of claim 1, wherein said device is a lumen.

3. The apparatus of claim 1, wherein said sterilant is from the group consisting of hydrogen peroxide and peracetic acid.

4. The apparatus of claim 1, wherein said source of sterilant is selected from the group consisting of an injector, a liquid flow-through device, a liquid reservoir and aerosol spray device.

5. The apparatus of claim 1, wherein said source of sterilant is placed inside said chamber.

6. The apparatus of claim 5, wherein said source of sterilant is a liquid reservoir placed inside the chamber.

7. The apparatus of claim 1, wherein said gas and vapor flow conduit is constructed for releasible connection.

8. The apparatus of claim 7, wherein said gas and vapor flow conduit connects one of said two open ends of multiple devices simultaneously to said first flow path of said vapor exhaust flow restrictor, said first flow path allowing exhaust flow out of said sterilization chamber through said vacuum valve and vacuum source.

9. The apparatus of claim 1, wherein said first and second flow paths each have an opening with an opening area, and wherein said first flow path is a continuously open flow path open to flow in both directions and which allows exhaust flow out of said sterilization chamber through said vacuum valve and vacuum source.

10. The apparatus of claim 9, wherein said first flow path is constructed with multiple conduits connected to said sterilization chamber side of said flow path, wherein said conduits allow air venting and exhaust flow into and out of said chamber respectively, from more than one location inside said chamber.

11. The apparatus of claim 9, wherein said first flow path further comprises a valve, said valve being capable of opening or closing said first flow path.

12. The apparatus of claim 9, wherein said second flow path allows flow only in the direction of said sterilization chamber exhaust port allowing exhaust flow out of said sterilization chamber through said vacuum valve and vacuum source and which does not allow the influx of air from outside said sterilization chamber and wherein said second flow path is connected to said gas and vapor flow conduit and through said conduit to one of said two open ends of said device to be sterilized.

13. The apparatus of claim 12, wherein the ratio of said flow of said first flow path to said flow of said second flow path is such that the sterilization vapor exhaust flow through said first and second flow paths results in maximum efficiency of sterilization of said device to be sterilized.

14. The apparatus of claim 12, wherein the ratio of said opening area of said first flow path to said opening area of said second flow path is between 1.0 and 2.0.

15. The apparatus of claim 12, wherein the ratio of said opening area of said first flow path to said opening area of said second flow path is 1.65.

16. The apparatus of claim 12, wherein said vapor exhaust flow restrictor has more than one opening for each flow path.

17. The apparatus of claim 1, wherein said vacuum source is a vacuum pump.

18. The apparatus of claim 1, wherein the sterility of said device is maintained following sterilization with an enclosure, wherein said enclosure completely encloses said device.

19. The apparatus of claim 18, wherein the enclosure comprises a flexible material.

20. The apparatus of claim 19, wherein said flexible material is comprised of non-woven polypropylene.

21. A method for sterilizing the interior and exterior of a device with at least two open ends and a flow path therebetween, comprising the steps of:

(a) placing said device into a sterilization chamber having an exhaust port;

(b) connecting one of said open ends of said device to a first end of a gas and vapor flow conduit having a first and second end, the second end of which is connected to a first flow path of a vapor exhaust flow restrictor having at least two flow paths, said first flow path of said vapor exhaust flow restrictor allowing exhaust flow out of said sterilization chamber through a vacuum valve and vacuum source;

(c) introducing a liquid or vapor sterilant into said sterilization chamber;

(d) exposing said device to negative pressure with the use of said vacuum source for a time sufficient to provide sterilization vapor directly to the interior and exterior of said device, wherein said exposing can be before or after said introducing in step (c);

(e) exposing said device to negative pressure with the use of said vacuum source to create a negative pressure differential at said exhaust port of said sterilization chamber and the use of said vapor exhaust flow restrictor for a time sufficient so that part of said sterilization vapor flows through said flow path of said device to sterilize said devices, through said gas and vapor flow conduit, and out of said sterilization chamber and the remainder of said sterilization vapor flows directly out of said sterilization chamber without passing through said gas and vapor flow conduit and said flow path of said device.

22. The method of claim 21, wherein said device is a lumen.

23. The method of claim 21, wherein said sterilant is from the group consisting of hydrogen peroxide and peracetic acid.

24. The method of claim 21, wherein said introducing of said sterilant comprises delivery via one or more methods selected from the group consisting of injection, liquid flow-through, a liquid reservoir and aerosol spray.

25. The method of claim 21, further comprising the step of exposing said device to a plasma after step (d) or prior to or after step (e).

26. The method of claim 25, wherein said plasma is generated in a second, separate chamber and said method further comprises the step of flowing said plasma into said sterilization chamber.

27. The method of claim 21, further comprising warming said device to be sterilized in said sterilization chamber prior to step (c).

28. The method of claim 27, wherein said device to be warmed is warmed with an applied electric field at low pressure.

29. The method of claim 27, further comprising the step of exposing said device to a plasma following step (e).

30. The method of claim 29, wherein said plasma is generated in a second, separate chamber and said method further comprises the step of flowing said plasma into said sterilization chamber.

31. The method of claim 21, further comprising the step of enclosing said device completely in an enclosure prior to step (a) to maintain the sterility of said device following sterilization.

32. The method of claim 31, wherein said enclosure is comprised of non-woven polypropylene.

33. The method of claim 21, wherein steps (c) through (e) are repeated one or more times.

34. The method of claim 21, further comprising the step between the first and second exposing steps (d) and (e) of venting air directly into said sterilization chamber for a time sufficient for the air and sterilization vapor mixture to come in close contact with said device to be sterilized.

35. The method of claim 34, wherein steps (c) through (f) are repeated one or more times.

36. The method of claim 21, further comprising the step between the first and second exposing steps (d) and (e) of venting air through said second flow path in said vapor exhaust flow restrictor of step (b), said second flow path continuously open to said sterilization chamber, for a time sufficient for the air and sterilization vapor mixtures to come in close contact with said device to be sterilized.

37. The method of claim 36, wherein steps (c) through (f) are repeated one or more times.