METHOD AND APPARATUS FOR STERILIZING MEDICAL INSTRUMENTS

Abstract

A method and apparatus for sterilizing a medical instrument, such as a dental instrument. The method includes placing the medical instrument in a chamber, providing a sterilizing agent including recombined ionized humidified air, controlling the temperature of the medical instrument and/or the chamber such that the temperature of the medical instrument is below the temperature of chamber, and at least partially condensing the sterilizing agent onto the instruments.

Claims

1. A method for sterilizing a medical instrument, including: placing the medical instrument in a chamber; providing a sterilizing agent including recombined ionized humidified air; controlling the temperature of the medical instrument and/or the chamber such that the temperature of the medical instrument is below the temperature of chamber; and at least partially condensing the sterilizing agent onto the instruments.

2. The method according to claim 1, including cooling or maintaining the medical instrument below the temperature of the chamber.

3. The method according to claim 2, including cooling the medical instrument prior to placing the medical instrument in the chamber.

4. The method according to claim 2, including cooling the medical instrument inside the chamber.

5. The method according to claim 1, including heating or maintaining the walls of the chamber above the temperature of the medical instrument.

6. The method according to claim 1, including cooling or maintaining the medical instrument to below the dew point of at least one of the components of the sterilizing agent.

7. The method according to claim 1, including heating or maintaining the walls of the chamber above the dew point of at least one of the components of the sterilizing mixture.

8. The method according to claim 1, wherein the medical instrument is placed in a container, and the container is placed in the chamber.

9. The method according to claim 8, including cooling the container to below the temperature of the chamber.

10. The method according to claim 1, including reducing the pressure inside the chamber prior to providing the sterilizing agent to the chamber.

11. The method according to claim 1, including cooling the medical instrument using a gas or gas mixture, such as air.

12. (canceled)

13. The method according to claim 1, wherein the step of providing the sterilizing agent includes: providing a plasma source; feeding a humidified air stream through the plasma source, at least partially ionizing the air stream; and allowing the air stream to at least partially recombine.

14. The method according to claim 1, wherein the sterilizing is performed at or below ambient pressure.

15. The method according to claim 1, including washing the medical instruments prior to sterilization.

16. The method according to claim 11, including washing the medical instruments prior to sterilization, wherein the cooling gas stream is supplied to the washed medical instruments for drying and cooling the medical instruments.

17. An apparatus for sterilizing a medical instrument, including: a chamber arranged for placing the medical instrument therein; a sterilizing agent source arranged for providing a sterilizing agent including recombined ionized humidified air; and a temperature control unit arranged for controlling the temperature of the medical instrument and/or the chamber such that the temperature of the medical instrument is below the temperature of chamber for allowing the sterilizing agent to at least partially condense onto the instrument.

18. The apparatus of claim 17, wherein the temperature control unit includes a cooling unit arranged for cooling or maintaining the medical instrument below the temperature of the chamber.

19. (canceled)

20. (canceled)

21. The apparatus according to claim 17, wherein the temperature control unit includes a heating unit arranged for heating or maintaining the walls of the chamber above the temperature of the medical instrument.

22. The apparatus according to claim 17, further including a container arranged for receiving the medical instrument, and arranged for being placed in the chamber, wherein the cooling unit is arranged for cooling the container to below the temperature of the chamber.

23. (canceled)

24. (canceled)

25. The apparatus according to claim 17, wherein the cooling unit includes a gas conduit for cooling the medical instrument using a gas, such as air.

26. (canceled)

27. The apparatus according to claim 17, including a plasma source, having an input port for feeding a humidified air stream into the plasma source, and an output port for feeding the air stream to the chamber while allowing the air stream to at least partially recombine.

28. (canceled)

29. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Embodiments of the present invention will now be described in detail with reference to the accompanying drawings in which:

[0033] FIG. 1 shows a schematic representation of an example of an apparatus;

[0034] FIG. 2 shows a schematic representation of a flow chart;

[0035] FIG. 3 shows a schematic representation of an example of an apparatus; and

[0036] FIG. 4 shows a schematic representation of an example of an apparatus.

DETAILED DESCRIPTION

[0037] FIG. 1 shows a schematic representation of an example of an apparatus 1 for sterilizing a medical instrument 2. The apparatus 1 includes a chamber 4. The chamber 4 is arranged for placing the medical instrument 2 to be sterilized therein. In this example, the chamber 4 is arranged for placing a plurality of medical instruments 2 to be sterilized therein. The apparatus 1 includes a sterilizing agent source 6. The sterilizing agent source 6 is arranged for providing a sterilizing agent 8. The sterilizing agent 8 includes recombined ionized humidified air. The apparatus 1 includes a temperature control unit 10. In this example, the temperature control unit 10 includes a cooling unit 10A. The cooling unit 10A is arranged for cooling the medical instruments 2.

[0038] The chamber 4 includes walls 12 forming an internal space 14 for receiving the medical instruments 2. In this example, the chamber 4 has a door 16 for allowing the medical instruments 2 to be inserted into and extracted from the internal space 14 of the chamber 4. The chamber 4 includes a sterilizing agent supply port 18. The chamber 4 includes an exhaust port 20.

[0039] The sterilizing agent source 6 here includes a plasma source 22. The plasma source 6 includes an input port 24 for feeding a humidified air stream into the plasma source 6. In FIG. 1 the input port 24 is connected to a an air stream supply 26 via a humidifier 28. The plasma source 6 includes an output port 30 in communication with the sterilizing agent supply port 18 of the chamber 4.

[0040] The cooling unit 10A in this example includes a gas conduit 32 for cooling the medical instrument using a gas, here air. The gas conduit 32 includes a mouth 34, here nozzles, pointing a stream of the gas onto the medical instrument 2.

[0041] The apparatus 2 can be used as follows. FIG. 2 shows a schematic representation of a flow chart of a method for sterilizing a medical instrument. In a first step 102 medical instruments 2 are cooled by activating the cooling unit 10 and having the stream of cooling gas impact and cool the instruments 2. The instruments 2 to be sterilized are placed in the internal space 14 of the chamber 4 in step 104. The step 104 can be performed before step 102, after step 102, or both before and after step 102. The medical instruments 2 are cooled to below the temperature of the chamber 4, here to below the temperature of the walls 12 of the chamber 4. The temperature control unit 10 can include a heating unit 10B arranged for heating or maintaining the walls 12 of the chamber 4 above the temperature of the medical instrument 2, or above the ambient temperature. In this example, the pressure in the chamber 4 is reduced 106, e.g. to about 100 mbar. Thereto a pump 38 connected to a pumping port 40 of the chamber 4 can be activated.

[0042] An air stream is supplied 108 to the input port 24 of the plasma source 6 via the humidifier 28. Depending on the humidity of the air supplied to the humidifier, the humidifier can add or remove water from the air such that at the exit of the humidifier an air stream with a predetermined humidity is obtained. In this example, the air stream entering the plasma source has a predetermined specific humidity, SH. The specific humidity of the air entering the plasma source 6 can e.g. be 10±1 g/kg (grams of water per kg of air). In the plasma source 6 the air is ionized 110. The ionized air is fed from the plasma source 6 into the sterilizing agent supply port 18 of the chamber 4. During transport the ionized humidified air, at least partly, recombines. The sterilizing agent formed by the at least partly recombined ionized humidified air then contacts 112 the medical instrument to be sterilized. As the medical instrument had been cooled, the sterilizing agent, at least partially, condenses 114 onto the medical instrument and sterilizes the medical instrument. As the walls 12 of the chamber 4 are not cooled, less cooled than the medical instruments, or even heated, condensation of the sterilizing agent onto the walls 12 can be prevented. After sterilization the sterilizing agent can be removed from the chamber 4 via the exhaust port 20. A destructor 42 may be placed in communication with the exhaust port 20 for destructing any contaminants carried by the exhausted sterilizing agent.

[0043] FIG. 3 shows a schematic representation of an example of an apparatus 1 for sterilizing a medical instrument 2. The example of FIG. 3 is similar to the example of FIG. 1. A main difference is that the apparatus 1 of FIG. 3 further includes a container 44. The container 44 is arranged for holding the medical instrument 2, here for holding a plurality of medical instruments 2. The container in this example includes a tray 44A and a lid 44B. The container 44 can be opened by removing the lid 44B from the tray 44A for placing one or more medical instruments 2 inside the container 44. The container 44 is arranged for being placed in the chamber 4. The chamber 4 can include guides for holding the container 44. The apparatus 1 in this example is arranged for opening the container inside the chamber 4. In the example of FIG. 3 the cooling unit 10 is arranged for cooling the container 44 to below the temperature of the chamber 4. Hence, the medical instruments 2 in the container 44 can easily be cooled together with the container 44. Also, hence the container 44, which can be contaminated as well, can easily be sterilized. After sterilization, the container 44 is closed, preferably while still inside the chamber 4. The container 44 can be arranged to be closed hermetically, or at least provide a microbial barrier preventing microbes from entering the inner space of the container.

[0044] In the example of FIG. 3 the cooling unit 10 includes an atomizer 46 for atomizing water into a cooling gas stream and impacting the atomized water and cooling gas stream onto the medical instruments 2 and/or onto the container 44.

[0045] FIG. 4 shows a schematic representation of an example of an apparatus 1 for sterilizing a medical instrument 2. The example of FIG. 4 is similar to the example of FIG. 3. A main difference is that the apparatus 1 of FIG. 4 further includes a cooling chamber 46. The cooling chamber 46 is arranged for holding the medical instrument 2, here for holding the container 44 holding medical instruments 2 while cooling the medical instrument(s) 2 and optionally the container 44. In this example the medical instruments 2, here in the container 44, are cooled in the cooling chamber 44 and then transferred to the chamber 4 for sterilization. The apparatus 1 can include a handler unit for transferring the medical instruments 2 and/or the container 44 from the cooling chamber 46 to the sterilization chamber 4 after cooling.

[0046] Herein, the invention is described with reference to specific examples of embodiments of the invention. It will, however, be evident that various modifications and changes may be made therein, without departing from the essence of the invention. For the purpose of clarity and a concise description features are described herein as part of the same or separate embodiments, however, alternative embodiments having combinations of all or some of the features described in these separate embodiments are also envisaged.

[0047] In the example of FIG. 1 the cooling unit is arranged for cooling the medical instrument inside the chamber. It is also possible that alternatively, or additionally, the cooling unit is arranged for cooling the medical instrument prior to placing the medical instrument in the chamber.

[0048] In the example of FIG. 3 the cooling unit includes an atomizer. It will be appreciated that the cooling unit of FIG. 1 can also include an atomizer. Also, the atomizer can be omitted from the cooling unit of FIG. 3.

[0049] In the example of FIG. 4 the apparatus includes a cooling chamber. It will be appreciated that the cooling chamber can also be used in the apparatus of FIG. 1.

[0050] The walls of the chamber are not cooled, less cooled than the medical instruments, or even heated. Thereto a heating unit is described in view of the examples. It will be appreciated that the apparatus can also include a chamber cooling unit arranged for cooling the chamber to a temperature above the temperature of the medical instrument. It will be clear that it is also possible that the apparatus includes an instrument heating unit arranged for heating the medical instrument to a temperature below the temperature of the chamber.

[0051] It is possible that the apparatus further includes a washing unit arranged for washing and/or rinsing the medical instruments prior to sterilization. Preferably, the medical instruments are dried prior to sterilization. The cooling gas stream, optionally including the atomized water, can be supplied to the washed medical instruments for drying and cooling the medical instruments.

[0052] However, other modifications, variations, and alternatives are also possible. The specifications, drawings and examples are, accordingly, to be regarded in an illustrative sense rather than in a restrictive sense.

[0053] For the purpose of clarity and a concise description features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features described.

[0054] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word ‘comprising’ does not exclude the presence of other features or steps than those listed in a claim. Furthermore, the words ‘a’ and ‘an’ shall not be construed as limited to ‘only one’, but instead are used to mean ‘at least one’, and do not exclude a plurality. The mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot be used to an advantage.