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Publication numberUS3092106 A
Publication typeGrant
Publication dateJun 4, 1963
Filing dateAug 4, 1958
Priority dateAug 4, 1958
Publication numberUS 3092106 A, US 3092106A, US-A-3092106, US3092106 A, US3092106A
InventorsButler William F
Original AssigneeCutter Lab
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Administration equipment
US 3092106 A
Abstract  available in
Images(1)
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Claims  available in
Description  (OCR text may contain errors)

June 4, 1963 w. F. BUTLER ADMINISTRATION EQUIPMENT Filed Aug. 4, 1958 MM UN m m T T m m m o a z .H Wm M .Y/ W E m I A I a break in the flask or in leakage about the stopper.

United States This is a continuation-in-part of application Serial No. 591,766, filed June 15, 1956, now abandoned.

This invention relates to equipment for the administration of a parenteral solution and the like, and to the use of such equipment.

Parenteral solutions have been supplied heretofore in containers sealed with some type of special closure, at one end, usually one having a relatively large through passage to admit the end of a drip meter. Typical structures representative of this are shown in US. Patents 2,688,533, 2,770,234, and 2,775,240. When it was desired to administer the container contents, the special closure was exposed and thereafter attachment was made of an administration set. During this period, the container contents were exposed to atmospheric contamination through the large open passage in the stopper. After the attachment was made, it was necessary to manipulate the apparatus to establish the liquid level in the drip meter so that fluid flow to the patient could be observed and controlled. This manipulation involved air-fluid intermixing resulting in possible air entrainment with the risk of embolism to the patient and fluid contamination, obviously an objectionable practice but one heretofore considered necessary.

In accordance with this invention, I provide a container completely closed by a sealed resilient stopper; the container contents are sterile and ready for use. In accordance with this invention, connection to the container is made by piercing the sealed stopper with the spike end of a drip meter under such conditions that the sterile character of the container contents is not destroyed or impaired. Thus, no unfiltered atmospheric air is admitted to the container during this operation because fluid communication with the container is established only upon insertion of the drip meter. Also, this method of operation makes it possible to establish the fluid level in the drip meter without air inter-mixing and without admitting atmospheric air to the set or to the container. Each of these is of substantial advantage. The fluid level in the drip meter must be established before fluid admiriistration to a patient can be undertaken because without a satisfactory fluid level, drops impinging on the lower end of the drip meter tend to entrap air and carry it to the patient. Obviously, this cannot be achieved with accuracy when a mass of bubbles is present in the drip meter. In addition, admission of atmospheric air destroys I the sterility of the container contents.

The device of the present invention is particularly useful in the administration of parenteral solutions which are packaged in a container under a reduced pressure. The packaging of such solutions under reduced pressure has numerous advantages. For example, when utilized with such a device as that provided by the present invention, the person effecting the administration to a patient is assured that the contents of the container have not unknow'lingly been subjected to contact with the atmosphere and so contaminated. This can occur through a These atent mamas Patented June 4, 1963 ice and other advantages will become further apparent hereinafter wherein the operation of the device is related in some detail. Simply stated, the operation includes packaging of the solution in a container under sterile conditions and under a reduced pressure. The container is sealed with a stopper and, in this condition, is handled, transported and stored until its use is desired. When the solution in the container is to be administered, the sterile spike on a drip meter providing part of the sterile administration set is forced through the stopper to establish fluid connection to the container. The sterile air in the administration set equalizes in pressure with the container, the drip meter filling partially as a result of this. The set-up is then ready for use.

The device of the present invention is of a simple shape and has few parts, thus facilitating manufacture and sterilization and enabling the device to be made of an inexpensive, disposable plastic material. Since it does not include any moving parts, there is nothing to go amiss with the device and it is thus reliable in operation.

The invention includes other objects and features of advantage, some of which, together with the foregoing, will appear hereinafter wherein the present preferred form of administration equipment embodying the present invention is disclosed. In the drawing accompanying and forming a part hereof, FIGURE 1 is a side elevation, partly in section, showing a typical administration equipment set-up, while FIGURE 2 is an enlarged sectional view of a portion of the apparatus.

FIGURE 3 is a view of the top of the drip meter attachment shown in FIGURE 2.

FIGURE 4 is a side elevation partly in section showing the stopper in an unopened container, while FIGURE 5 is a similar view with the stopper ready for piercing by a sterile spike on an administration set.

Referring to the drawings, I have indicated at 51 the neck and outlet portion of a container, the latter being closed with a suitable flexible closed stopper 49'. The stopper is adapted to receive a fitting or outlet member, generally indicated at 43, and further described in detail; the fitting 43 is usually provided at one end of an administration unit including a drip meter, generally indicated at 41. The outlet member 43 and the drip meter 41 can be made as separate units or they can be integral as I have shown. The other end of the drip meter 41 is attached to one end of a length of flexible tubing 11, the latter including a control valve, generally indicated at 12. The other end of the tubing 11 is joined to a piece of flexible rubber tubing 16, the latter being attached to one end of a needle adapter 17 carrying a suitable needle 18-. Needle 18 and the spike end on the drip meter are each usually enclosed in a sterile cover; the covers have been removed for purposes of illustration.

The drip meter 41 includes a separate conical barrel 42 connected at one end to the tube 11 and the associated parts, as has been previously described. At its upper end, barrel 42 includes the fitting or closure 43 aflixed to the end of the barrel 42. The closure includes a central fluid inlet passage 44, the latter continuing to within the barrel 42, a tubular projection 46 depending into the barrel for this purpose and providing an orifice off which fluid drops; the barrel 42 is transparent so the release of fluid can be observed. Preferably, the tubular projection 46 providing the passage 44 terminates in a sharpened conical end 4-7 to aid in its insertion through the flexible closed stopper 49 in container 51.

To admit of air entering the container after insertion of the fitting 43, an air inlet passage 52 is provided within a tubular projection 53 formed integrally as part of the closure 43 and of the conical end 47, the tubular projection 53 terminating in a sharpened angular end 54- to aid in insertion into the stopper 49 and projecting beyond the end 47. The tubular projection 53 includes a side arm 56, over which is placed a tubular cap '7, the

'latter including a filter 61 held between a shoulder 62,

integral with the cap 57, and the turned over end 58 of the cap; the turned over end includes an air inlet 59.

One can use any suitable material for the filter 61 providing it has suflicient porosity to admit air readily and yet has sufficient fineness to ensure removal of any airborne contaminants which might otherwise find their way into the container. I have used an excellent grade of a cellulose filter medium, particularly that known as Micronite. It is also desirable that the filter medium 61 be one which will not be wet by the fluid in the container 51 in the event that the clamp 12 is closed at any time and flow of fluid is discontinued. This is important because if the filter is one which can be wet by the fluid, then the fluid can leak from the container past the filter; this does not occur with a non-wetting filter which thus acts as its own check valve. Further, if the fluid wets the filter, the pores of the filter may become closed with the result that air will not enter into the container 51. Preferably, one can use any of the silicones such as are disclosed in Us. Patents 2,504,482 and 2,622,598, to prevent wetting of the filter. The silicone is dissolved in a solvent such as water or acetone to provide a 1%- 2% solution, which is then applied to the filter material which is then freed of solvent.

A further advantage of the present structure as compared to one including a check valve is in the ease with which an administration set including the structure of this invention can be placed in operation. With a ballcheck valve set, it is necessary to jar repeatedly the fluid container and valve to establish fluid flow. Until a fluid stream of adequate length is established in the administration line, fluid can and will leak past the check valve. This disadvantage is absent in the present set since the fluid cannot pass the filter.

The administration set described is designed particularly as has been mentioned, for use with a solution bottle containing a liquid under a sub-atmospheric pressure. Referring particularly to FIGURES 4 and 5 in the drawing, I have shown the stopper 49 provided in the neck of a glass container 51. The stopper is retained in place by a protective metal cap 8. To protect the sterility of the stopper, a cover disc is placed over the stopper 49 and the upper portion of cap 8. The disc 10 is held in place by a removable protective outer cap 9. The retention of a closure by a metal cap and a removable outer metal cap are well-known in the art and need not be described further. The outer surface of the stopper is sterile, as provided by the manufacturer. In some instances, the outer cap 9 and the disc 10 are removed and the stopper surface is wiped with an alcohol swab.

The container closure 49 is preferably made of a flexible resilient material such as rubber or other suitable elastomer; it includes a shoulder portion 11a and a plug portion 12 adapted to fit within the neck of the container in tight sealing engagement. Preferably, the closure is formed in one piece to include an outer integral diaphragm 14 covering a central passage 16 extending only partially through the closure. The closure also includes a septum or wall 17 defining a portion of the central passage 16 and having an aperture therein of a size such that upon insertion of the projecting portion of the drip meter, wall 17 is engaged in tight frictional engagement. Preferably, the wall or septum 17 is spaced from the diaphragm 14 by recess 19, of such size that those portions of the diaphragm which are cut and displaced upon insertion of the drip meter are received within the annular recess 19. The cut and displaced portions are thus kept from between the drip meter and the side wall of the central passage 16 where they would serve to make the seal about the drip meter imperfect so that unfiltered atmospheric air might enter. The stopper structure defined is typical of various container closures which can be employed and the invention is not limited to this stopper.

In use, the administration set and the container are usually supplied as separate entities. As has been described, the end of the stopper 49 is supplied in sterile condition or is re-sterilized readily by wiping with an alcohol swab. The end of the drip meter is usually supplied in a sterile condition, a suitable cover being provided over the pointed end. When it is desired to effect administration of the solution in the container, it is only necessary to expose the two completely sterile surfaces for an instant before the end of the drip meter is forced into stopper 49, the only engagement being between the two completely sterile surfaces which are exposed to the atmosphere for only an instant. Thereafter, as the solution is withdrawn, only filtered air is admitted to the container.

The drip meter structure provided possesses other unique advantages when used in combination with a container in which the contents are under a sub-atmospheric pressure and one of these advantages is the ease with which one can establish an adequate fluid level in the drip meter barrel 41. Also, when the end of the drip meter passes into the container, partial relief of the reduced pressure in the container occurs. With the container placed in such a position that the atmosphere admitted from the connected administration set passes through the liquid in the container, the operator is assured of the suitability of the solution for administration by this indication. If the partial pressure in the container has been relieved and a substantial sub-atmospheric pressure is not present therein, violent agitation of the liquid by the entrance of the atmosphere from the administration set will be absent and the operator will know the container and its contents are suspect.

It is preferred to effect connection of the administraiton set with the container so placed that the plug 49 is covered with the fluid in the container. This is preferably achieved by making the connection with the container inverted, as in FIGURE 1; the same effect can be achieved if the container is lying on its side, in which case a maximum level is achieved in the drip meter barrel. Connection can also be effected with the container standing in its normal position, in which case the bottle should either be inverted promptly or the end of the filter should first be covered manually to prevent air entrance; the filter normally provides such pressure drop that pressure equalization occurs preferentially as between the administration set and the container rather than between the container and the atmosphere through the filter.

When it is desired to effect fluid administration to a patient, the separate filled container and the separate administration set are assembled. The container is then in the condition in which it appears in FIGURE 4, that is, the outer protective cap 9 and the disc 10 are in place. These are removed, the cap 9 being torn away to release the disc and so expose the sterile surface of the stopper. Concurrently, the cover on the sharp end of the drip meter is removed. With the container in a position in which the liquid content covers the stopper, that is, with the container inverted as in FIGURE 1 or lying on its side so that the stopper is covered, the sharp sterile end of the drip meter is forced through the diaphragm portion 14 of the stopper, the two sterile surfaces being exposed to the atmosphere only momentarily. Immediate 1y upon piercing of the stopper, the sterile atmosphere in the administration set (which is at atmospheric pressure) rushes into the low pressure area provided by the container, this being made evident to an observer because of the bubbles which break the surface of the fluid in the container. This gives assurance to the operator that the container is in the condition in which it was packed by the manufacturer and therefore is sterile. As pressure equalization occurs, liquid from the container passes into the drip meter and establishes a fluid level therein. The sterility cover is then removed from the needle 18 and clamping means 12 opened to permit some fluid to pass through the tube 11 and issue from the needle 18 so that the entire system is filled with fluid and no air is present. When the operator is satisfied that the fluid system from the drip meter to the end of the needle is filled with liquid, needle 18 is ready for insertion into an appropriate location in the patient. When this is efifected, the rate of flow from the container is regulated by the flow control means 12, the flow being controlled by observing the liquid level in the drip meter.

Following pressure equalization and establishment of the proper fluid level in the drip meter barrel, valve 12 is opened and fluid is permitted to pass out of the needle 18 to establish a complete and full fluid system. Needle 18 may then be inserted in the desired location in the patient and the administration of fluid commenced. It will be apparent to those skilled in the art that this operation is highly advantageous for it provides ready establishement of the proper level in the drip meter, gives assurance that the contents of the container are uncontaminated, and provides a filled fluid system for administration of a solution to a patient, without intermixing of the fluid and the air in the administration set. These advantages are not present in any of the prior art structures or manipulations heretofore available.

From the foregoing, I believe it will be apparent that I have provided novel, simple and improved administration equipment, which can be used in a novel manner to ensure administration of a sterlie medium to a patient.

I claim:

1. Apparatus for intravenous administration of fluid, said apparatus including a flexible tube having a needle adapter at one end thereof and a drip meter at the other, said tube having clamping means thereon sealing said tube against passage of fluid, said drip meter including a transparent vessel having an adapter on a first end thereof secured to said flexible tube, whereby to provide for liquid-tight communication between said tube and meter, and a second opposite end having a closure member thereon adapted for use with a pierceable stopper mounted in the mouth of a flask of fluid to be administered, said closure member for said drip meter having a first passage extending therethrou-gh whereby to provide communication with the interior of said transparent vessel, said closure member for said drip meter having a second passage extending from one side thereof partially through said closure member and extending toward the said first passage, said second passage terminating in an orifice adjacent the side of said closure, said orifice being normally exposed to the atmosphere whereby to provide an air passage integral with the said closure member extending from a point adjacent one side of said closure member to the top of said closure member, said drip meter closure member having on the exterior end thereof an upright member of small cross-section having an end thereon adapted for piercing, the said passages extending through the said upright member longitudinally thereof and through the said end adapted for piercing; a pierceable stopper in sealing engagement about said upright member on said closure member; and a transparent flask containing fluid to be administered, the mouth of said flask being sealed by said stopper and said associated upright member, said flask and said drip meter being both under a partial vacuum relative to the outside atmosphere, the height of said flask and the length of said upright member being so proportioned that the said piercing end of the said member extends only slightly beyond the stopper sealing the mouth of the said flask and only a small fraction of the distance to the bottom of the said flask, the said first and second passages being of such a size at their most restricted points and the vacuum pre-existing within said flask being such that when the said flexible tube is temporarily obstructed, and said upright member pierces said stopper whilevthe said flask is in an inverted position, the air pressure within the said transparent vessel is decreased suificiently that fluid is drawn from the said flask and fills the said vessel about halfway.

2. The structure of claim 1 wherein each of said passages extends through the said upright member in an individual and distinct fashion, each passage terminating in a separate orifice at that end of said upright member adapted for piercing.

3. The structure of claim 1 wherein the said passages are of such a size at their most restricted points that on application of an identical vacuum to each, air preferentially flows through the said first passage.

4. Apparatus for intravenous administration of fluid including a flexible tube having a needle adapter at one end thereof and a drip meter at the other, said tube having clamping means thereon sealing said tube against passage of fluid, said drip meter including a transparent, frustro-conical vessel having an adapter on the narrow first end thereof for receipt of said tube whereby to provide for liquid-tight communication between said tube and meter, and a second opposite end having a closure member thereon adapted for use with a piercea-ble rubber stopper mounted in the mouth of a container of fluid to be administered, said closure member for said drip meter having a first passage extending through the top thereof, said passage extending completely through said closure member and providing communication with the interior of said transparent vessel, the exterior of said passage being defined by a first relatively rigid tube having a lead end adapted for piercing; said closure member for said drip meter having a second passage defined at one end thereof by a second relatively rigid tube, said second tube being positioned adjacent said first tube, said second tube terminating in an end adapted for piercing, said end being positioned adjacent the piercing end of the said first tube, said second passage extending partially through said closure and thereafter having an angular bend therein causing said passage to advance outwardly toward the side of said closure, said passage terminating in an orifice adjacent the side of said closure, said orifice being normally exposed to the atmosphere whereby to provide an air passage integral with the said closure member, said orifice having means in association therewith for removably securing a non-water-wettable air filtering means across said orifice whereby partially to obstruct the said air passage; the said first and second passages being of such a size at their most restricted points that on application of an identical vacuum to each, a sub stantial proportion of the total air passed flows through the said first passage; a rubber stopper in sealing engagement with said tubes of said drip meter closure member; and a transparent flask of fluid to be administered, the mouth of said flask being sealed :by said stopper and said associated closure member tubes, whereby said container and said drip meter are both under a partial vacuum relative to the outside atmosphere, the height of said flask and the length of said tubes being so proportioned that the said piercing ends of the said tubes extend only slightly beyond the stopper sealing the mouth of said flask and only a small fraction of the distance to the bottom of said flask, the said first and second passages being of such a size at their most restricted points and the vacuum pie-existing within said flask being such that when the said flexible tube is temporarily obstructed, and said upright member pierces said stopper while the said flask is in an inverted position, the air pressure with- 'in the said transparent vessel is decreased sufiieiently that fluid is drawn from the said flask and fills the said vessel about halfway.

References Cited in the file of this patent UNITED STATES PATENTS 8 Lager June/14, 1949 Rausch Jan. 1, 1952 Van Loghem Dec. 14, 1954 Ogle Aug. 7, 1956 Morrisey et al. Dec. 25, 1956 Shaw May 5, 1959 FOREIGN PATENTS France Mar. 3, 1954 France Aug. 11, 1954 Norway June 27, 1955

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Classifications
U.S. Classification604/251, 222/159, 222/88
International ClassificationA61M5/162, A61M5/14
Cooperative ClassificationA61M5/162, A61M2005/1623
European ClassificationA61M5/162