Vacuum Cannula Apparatus

Abstract

A vacuum curet for use with uterine aspirator apparatus. The curet has a cannula barrel with a suction port at one end, and a manifold or handle at the other. A capillary runs along the inner length of the cannula barrel terminating at the cannula tip at one end and at the manifold at the other. The entire length of the capillary is pressure-tight. The design permits introduction of appropriate fluid into the uterus at any time during the operative procedure. Introduction of the fluid may be accomplished in different ways. One way is to apply manual pressure on a squeeze tube connected either directly (or indirectly through tubing) to the curet manifold. Alternatively, a standard syringe is used in place of the squeeze tube.

Parent Case Text

This application is a continuation-in-part of my copending application entitled "Collection Bottle,"Ser. No. 63,480, filed on Aug. 13, 1970 and now U.S. Pat. No. 3,713,444.

Description

The invention relates generally to medical equipment and particularly to vacuum cannula apparatus used in uterine aspiration.

Within the past 15 years, a technique called uterine aspiration, or vacuum curettage, has been developed for performing abortions during the early months of pregnancy. The earliest reference to this technique appeared in an article by Y. T. Wu and H. C. Wu, entitled "Suction in Artificial Abortion - 300 Cases" in the Chinese Journal of Obstetrics and Gynecology, Vol. 6, 1958, beginning at page 447. A recent survey of the subject appeared in an article by D. Kerslake and D. Casey entitled,"Abortion Induced by Means of Uterine Aspirator" in Obstetrics and Gynecology, Vol. 30, July, 1967, pages 34 -45. Very briefly, the technique is to aspirate the conceptus from the uterus using a tube which has a flexible connection to a source of suction. A typical apparatus includes a suction curet having an oval mouth at its end, or on one side, and an air hole at the other end to control the suction. A rubber pressure tubing connects the curet to a transparent, e.g., glass, container which in turn is connected to a suction pump. Aspriation of the uterine contents usually takes less than 2 minutes and the debris can readily be seen as it appears in the glass container.

The method employed may be very briefly reviewed. The perineum, vagina, and cervix are disinfected. The cervix is then drawn forward with a vulsella. The direction of the cervical canal and the depth of the uterine cavity are determined with a uterine sound. It is a common practice to dilate the cervix to allow easy insertion of the suction curet. However, dilation may be unnecessary in certain cases, and when not needed, an anesthesia generally is not used. When dilation is required, a local or general anesthesia is administered. The suction curet of appropriate diameter and design is inserted carefully into the cervix. The suction is then started. In a few seconds the suction reaches the working level which typically is at a mean level of 18 inches of mercury (relative). The suction curet is moved gently up and down over all aspects of the uterine cavity. The debris from the conceptus passes visibly into the glass container, either whole or piecemeal. The degree of suction can be controlled with some aspirators by putting a thumb over an airhole in the handle of the curet as well as by using some devices on the pump. During the aspiration process, the uterus reacts by contracting and decreasing volume. Aspiration usually takes less than 2 minutes. It is though to be complete when the uterine wall feels smooth and no further debris emerge.

A typical apparatus used for uterine aspiration consists of a curet connected by a hose to collection bottle which in turn is connected by a second hose to a vacuum pump. An improved apparatus is shown and described in my copending U.S. Pat. application Ser. No. 63,480 have been described. The curets are usually made from metal or from converted strong urethral catheters. The advantage of metal is that for a given internal diameter, the external diameter can be less because of the strength of the material. However, transparent curets of either glass or plastic, e.g., plexiglas are popular because cleanliness is obvious and debris can be seen passing through during operation. Each aspirator apparatus is outfilled with several suction curets of different sizes, and sometimes, design. Curets have been used with oval openings both on the side and on the end to facilitate clearing the cornea. A four opening at the working end curet has been described. A double tube curet in which sterilized water (30-50ml/min)irrigates the uterus from the cavity between the tubes while the debris passes down the inner tube, has also been described. The average curet is 25 cm long with external diameters ranging from 3.5 mm to 15 mm with a mode of about 8 mm. The larger diameter curets are used for later pregenancies. The above cited D. Kerslake and D. Casey article reviews various types of curets.

During the normal progress of a uterine aspiration operation, less and less fetal material remains in the uterus, and the procedure becomes more and more static. Introduction of medicinal fluid during the procedure either constantly or intermittently, keeps the process dynamic, thus assisting remnant removal of the gentle flushing action thus established. As the operation progresses, the uterus contracts very tightly and it often becomes necessary to introduce the lubricating medicinal fluid at the later portion of the operation. The need for the medicinal fluid and lubricant becomes especially important if all the fetal material is not removed on the first attempt. It is desirable that the surgeon have complete control over the introduction of the medicinal fluid. As the operation progresses, and becomes more static, he may wish to introduce and rapidly increase and decrease the amount of surgical fluid. In the present invention the surgeon himself regulates the amount of fluid introduced, and may "feel" the amount of fluid introduced.

It is desirable that the apparatus for introducing the medicinal fluid be uncomplicated, and not require large amount of plumbing and hoses in the operating room, and if possible, not require a nurse or other operating room attendant for its proper functioning.

A further requirement of the equipment used for introducing medicinal fluid during a vacuum currettage is that it be sterile, because the fluid is introduced into the patient. Reservoir sources, while traditionally sterile, may become contaminated when they are introduced with pumps and piping or plumbing necessary for introducing the fluid.

It will be appreciated that because of the static nature of the uterus during the latter stages of the procedure, when the fluid is most needed, the fluid must be introduced under pressure, and this requires a pumping mechanism in the fluid reservoir source. This pressure source also must be both controlled and must not introduce any source of contamination.

These and other problems are solved in the present invention, which in one embodiment employs a surgical fluid reservoir in a plastic squeeze tube, which is mounted adjacent to the handle of the curet. A capillary tube extends from the sqeeze tube reservoir along the inside of the curet to a capillary tip opening near the end of the cannula adjacent to the suction port. The surgeon, in the course of the operation, when additional lubrication is needed, or at the routine end of the procedure, merely with the same hand holding the curet, squeezes the tube reservoir thereby applying pressure to the surgical fluid and forcing it to flow through the capillary tube on the inside of the cannula, and out of the cannula end at the capillary tube tip. The surgeon may introduce more or less fluid by squeezing the tube and thus adjusts the flow of fluid in the course of the operation. With this arrangement, the surgeon has complete control over the introduction of the surgical fluid. The cannula is of course, sterile prior to the operation, having been autoclaved, and the fluid source in the squeeze tube may be prepared under sterile conditions. The attachment of the squeeze tube to the cannula may be done with a sterile coupling, and typically a Luer lock connection may be used. The mating half on the squeeze would be sterile, and covered with a cap or other plastic member to insure its not being contaminated. Thus, the sterile condition of the medicinal fluid is insured, and the chance of contamination is minimized. it will be appreciated that in this present arrangement, the medicinal fluid is introduced by the surgeon himself, and it is not necessary to have an operating room attendant regulate the introduction of a medicinal fluid through an external pump or other pressure-introducing means. Furthermore, it is not necessary to have pumps or complicated equipment in the operating room for the introduction of the medicinal fluid, and the hoses and interconnections between such pumps and the curet are also avoided.

In an alternative embodiment of the invention, a standard syringe is mounted on the curet adjacent the handle. At the end of the operation, as is sometimes routinely done, between five and twenty cc of distilled water, or other medicinal fluid having an antiseptic and/or analgesic properties, are routinely introduced. At the completion of the operation, the surgeon would pause for a moment, depress the plunger on the syringe to force the fluid into the uterus, and then continue the operation to remove the injected fluid. Here, again, the fluid reservoir source is mounted on the curet and may be discharged by the surgeon himself without the mandatory assistance of a nurse and without requiring additional pumping of liquid handling apparatus in the operating room.

According to another aspect of the invention the cannula is of a novel design having a very small diameter capillary tube extending down the inside wall of the cannula barrel. The capillary tip is located proximate to the port but further towards the end of the cannula and closer to the opposite side of the cannula.

A further application of the cannula of this invention is in the use of abortions performed during the second trimester. Vacuum is considered to be less and less effective after the 12 week of pregnancy. Abortions by saline injection seems safer and more effective after this period. Saline injection is accomplished by withdrawing an appropriate amount of amniotic fluid surrounding the fetus and replacing it with an equal amount of saline solution, which induces abortion by natural means. The basic cannula, connected to a suitable saline source may be used for this technique. The cannala barrel under vacuum is used to withdraw the amniotic fluid and then after the vacuum has been shut off, the saline solution is introduced into the uterus through the capillary.

The above and other objects, features and advantages of this invention will be apparent in the following detailed description of illustrative embodiments thereof which are to be read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a vacuum curettage apparatus having the vacuum cannula of this invention.

FIG. 2 is a side view of vacuum cannula apparatus of this invention.

FIG. 3 is an end view of a portion of the vacuum cannula apparatus of FIG. 2.

Referring to FIG. 1, there is shown a perspective view of a vacuum curettage apparatus, in which there is shown a curet generally indicated at 10 connected by a hose 12 to a collection bottle 14, which in turn is connected by a second hose 16 to a vacuum pump 18. The collection bottle is of an improved kind, shown and described in detail in my copending U.S. Pat. application Ser. No. 63,480 filed on Aug. 13, 1970. For a further detaied explanation of such collection bottles, reference is made to said application. A standard 50 cc syringe 20 is shown attached to the curet 10. The syringe is shown attached to the handle 22 of the curet and makes a communicating path with a capillary tube extending down the barrel of the curet to its tip. An additional curet 30 is shown adjacent to the curet 10. It is similar to curet 10 but of slightly different dimensions. It is customary to employ different size currets depending upon the needs of the operation. It will be noted that the curet 30, just beyond the handle, has two connectors: one connector 32 is to be made with the hose 12, the second connector 34 is to be made to the standard syringe.

Referring now to the drawings of FIG. 2 and 3, there is shown in FIG. 2 a side view of an alternative embodiment of the curet of the present invention, and in FIG. 3, an end view of the tip of the curet shown in FIG. 2 and taken along lines 3--3. The curet includes a cannula barrel 40 having a suction port 42 near one end. A capillary 44 extends along the inside length of the cannula barrel. The capillary terminates at its outer end in a capillary tip opening 46, which extends through the wall of the cannula barrel. This is shown in both FIGS. 2 and 3. The capillary tip opening is near the suction port, and as shown in the figure, is preferably further towards the end of the cannula than the suction port, and located on the side away from the port. At the other end of the cannula barrel is a manifold 48. The inside of the cannula barrel extends through the manifold to a tapered fitting 50. A handle 52, hollow along its length, fits onto the fitting 50. The other end of the handle 52 is provided with a coupling 54 suitable for interconnection with a hose which leads to a collection bottle. An optional vacuum control hole 56 is shown in the handle communicating with the hollow interior. The surgeon may regulate the pressure in the operating area by placing his thumb partially or wholly over this hole 56. In this Figure, the interchangeable handle is shown as part of the path leading from the suction port through the cannula barrel to the vacuum collection system. It should be appreciate that fixed handles may be employed, such as those shown in FIG. 1, or curets with handles that are not in the suction flow path may also be employed.

Referring again to the manifold 44, it will be seen that there is a second port 58 through the manifold connected to the capillary 44 and terminating in a Luer lock connection 60. A squeeze tube fluid reservoir 62 is shown having a mating Luer lock connection attached to the manifold connection 60.

The medicinal fluid is prepared and stored in the squeeze tube fluid reservoir 62. The fluid is sterile and the Luer lock connection 64 is also sterile and initially covered with a protective material. The cannula barrel and manifold are also sterile. When the operation is to be performed, the protective material (not shown) is removed from the Luer lock connection 64 and the squeeze tube fluid reservoir is attached to the manifold by the connectors 60, 64. The surgeon squeezes the tube reservoir 62 slightly, to force the fluid through the port 58 and capillary 88 until a small amount of fluid emerges at the capillary tip opening 46. This is to make sure there is no air in the capillary tube and to insure that no air is introduced into the uterus during the operation. The vacuum curettage than proceeds in the normal manner, and at the appropriate time, the surgeon can move his fingers from the handle 52 and squeeze the fluid from the reservoir 62. The fluid emerges at the capillary tip opening 46, and lubricates the tip of the cannula barrel and the adjacent portions. The quantity of medicinal fluid and its rate of flow is under the complete control of the surgeon.

The reservoir has been shown attached to the curet by a standard Luer lock connection 60, 64. It should be appreciated that any convenient or conventional locking means may be employed.

A curet apparatus has been constructed in accordance with the teaching of this invention and the following dimensions for that curet are set forth below. It should be understood however, that these dimensions are for purposes of dimensions only and variations may be made therefrom without departing from the spirit or scope of the invention.

cannula barrel length: 7 3/4inches

cannula barrel outside diameter: 5/16 inches

cannula barrel inside diameter: 0.2626 inches

capillary outside diameter: 0.0778 inches

capillary inside diameter: 0.0625 inches

Although illustrative embodiments of this invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention.

Claims

What I claim is:

1. A vacuum cannula apparatus comprising a cannula barrel having a curetting port at one end; capillary extending along the length of the barrel and terminating at a capillary-tip opening proximate to said port; a manifold at the other end of said barrel and including first means for connecting said capillary to a fluid source, and second means for connecting said barrel interiof to a vacuum source; handle means for manipulating the cannula apparatus; and a fluid source reservoir located adjacent to said handle means, and having connecting means to mate with said first connecting means on said manifold; said reservoir being self contained, and sealed but for said connection with said first connecting means, and of a hand squeeze type wherein the pressure and quantity of fluid expelled from said reservoir is regulated by manual pressure on said reservoir; whereby during an operation a surgeon manipulating said cannula with one hand on said handle means may also, squeeze said squeeze type fluid reservoir to regulate the fluid flow at the capillary tip.

2. An apparatus according to claim 1 wherein said fluid source reservoir is a syringe.

3. An apparatus according to claim 1, wherein said fluid source reservoir is a semi-rigid squeeze-tube.

4. An apparatus according to claim 3 wherein said squeeze-tube reservoir fits directly onto and is totally supported by said first connection means.

5. An apparatus according to claim 1, wherein said second connecting means includes a mechanically rigidly supportive connection to said handle means said mechanically rigidly supportive connection being such as to position said handle and said fluid source reservoir adjacent to one another, whereby a surgeon using the apparatus may grasp the fluid source and the apparatus with the same hand.

6. An apparatus according to claim 1 wherein said capillary-tip opening is located further toward the end of said cannula barrel than said port and on the opposite side of said cannula barrel from said port.

7. A vacuum curet apparatus comprising a cannula barrel having a curetting port at one end; a capillary extending along the length of the barrel and terminating at a capillary-tip opening located further toward said one end of said cannula barrel than said port and on the opposite side of said cannula barrel from said port; and a manifold at the other end of said barrel and including first means for connecting said capillary to a fluid source, and second means for connecting said barrel interior to a vacuum source.

8. A vacuum cannula apparatus comprising a cannula barrel having a port at one end; a capillary extending along the length of the barrel and terminating at a capillary-tip opening proximate to said port; a manifold at the other end of said barrel and including first means for connecting said capillary to a fluid source, and second means for connecting said barrel interior to a vacuum source; handle means for manipulating the apparatus; and a fluid source reservoir connectible to said first connecting means on said manifold; said reservoir being self contained, and sealed but for said connection with said first connecting means; and of a hand squeeze type wherein the pressure and quantity of fluid expelled from said reservoir is regulated by manual pressure on said reservoir; whereby during an operation a surgeon manipulating said cannula with one hand on said handle means may also squeeze said squeeze type fluid reservoir to regulate the fluid flow at the capillary tip.

9. A vacuum cannula apparatus comprising a cannula barrel having a port at one end; a capillary extending along the inner length of the barrel and terminating at a capillary-tip opening proximate to said port; and a manifold at the other end of said barrel and including first means for connecting said capillary to a fluid source, second means for connecting said barrel interior to an aspirator source; handle means at said first and second means for manipulation of said apparatus; a semi-rigid squeeze-tube fluid source reservoir connected to said first connection means and located adjacent to said handle, whereby during an operation a surgeon manipulating said cannula with one hand on said handle may also, with the same hand, squeeze said squeeze-tube fluid reservoir to regulate the fluid flow at the capillary tip; said squeeze-tube reservoir fits directly onto and is totally supported by said first connection means; and said squeeze tube reservoir and said first connecting means, include and are connected together by a Luer lock type fitting.

10. A vacuum cannula apparatus comprising a cannula barrel having a port at one end; a capillary extending along the inner length of the barrel and terminating at a capillary-tip opening proximate to said port; and a manifold at the other end of said barrel and including first means for connecting said capillary to a fluid source; second means for connecting said barrel interior to an aspirator source; said apparatus includes a handle for its manipulation; a semi-rigid squeeze-tube fluid source reservoir connected to said first connection means and located adjacent to said handle; whereby during an operation a surgeon manipulating said cannula with one hand on said handle may also, with the same hand, squeeze said squeeze-tube fluid reservoir to regulate the fluid flow at the capillary tip; said second connecting means includes a rigid tapered fitting; said handle having an air passage therethrough with one end rigidly mating with said tapered fitting, and the other end having means for making connection to the aspirator source.