US 3572333 A
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Description (OCR text may contain errors)
Mamh 231, 1971 F. H..HUBERT OBTURATOR Filed Oct. 14. 1968 2 I, Q 6 4 5 m 5 k /h 2 m INVENTOR 7 fRA/VZ H. fill/Jill,
BY 14, mm. @5214 v M ATTORNEYS United States Patent 01 Ffice Patented Mar. 23, 1971 3,572,333 OBTURATOR Franz H. Hubert, Carlstadt, N.J., assignor to Becton, Dickinson and Company, East Rutherford, NJ. Filed Oct. 14, 1968, Ser. No. 767,331 Int. Cl. A61m /00, 25/00 U.S. Cl. 128-214.4 4 Claims ABSTRACT OF THE DISCLOSURE A disposable plastic obturator which is adapted to occlude the entire bore of a catheter. The obturator includes an elongated stem having an enlarged head at one end which is encapsulated in a surrounding hub. The stem and hub are assembled by initially positioning the stem head against a shoulder in the bore of the hub, and then deforming an annular lip in the hub bore to overlie the top of the stem head.
BACKGROUND AND SUMMARY OF THE INVENTION The present invention relates to a surgical catheter, and more particularly to a disposable plastic obturator for closing the end of the catheter during periods of non-use.
It is common practice in blood transfusions, intravenous feedings, or when fluids are to be withdrawn from the human body, to insert a flexible plastic tube or catheter into a vein or other selected region of the vascular system. The catheter is generally introduced through a previously inserted tubular steel needle, or it may be designed to be introduced over the steel needle. In either event, the catheter is permitted to remain in position within the vein after the needle is withdrawn. Fluids may then be easily passed to or from the body at various intervals of time without the necessity for repeated needle punctures.
During periods of non-use, the external end of the catheter is normally closed by a Luer-cap or plug which prevent-s the escape of fluid. Difliculties arise however since presently used caps permit clotting of the blood in the bore of the catheter. To preclude such clotting, it is necessary to inject an anti-coagulant, such as a heparin solution, into the catheter.
It is therefore an object of the present invention to provide a plastic obturator which insures a leak-proof closure at the end of the catheter, and at the same time precludes the clotting of blood in the bore of the catheter without requiring an injection of an anti-coagulant solution.
It is a further object to provide an obturator which is simple in design, inexpensive to manufacture, and easily adapted for use with conventional catheters. Still another object is to provide an obturator which can be pre-sterilized and is disposable after use.
It is also an object of this invention to provide a method of assembling a stem and hub to form an obturator of the described type, the method being adaptable to high speed production techniques and at the same time producing a secure and permanent connection between the two members.
These and other objects are achieved in the embodiment of the present invention described herein, through the provision of an obturator which includes a flexible plastic stem having an enlarged head at one end. The enlarged head is encapsulated in a plastic hub to permanently join the two members. The flexible plastic stem is designed to enter the bore of the catheter to occlude and completely occupy the space in the bore and thereby prevent clotting of the blood or other fluid which would normally fill this space. The hub of the obturator may also include a circumferential flange which is spaced from the body to form an opening concentric to the axis of the stem, the opening being designed to receive and lock in place the terminal connector of the catheter.
The unique structure of the present invention is obtained by a method of manufacture which initially utilizes a plastic hub having a stepped bore and an axially extending annular lip positioned within the bore immediately above the shoulder formed in the stepped bore. An elongated plastic stem having an enlarged head at one end is positioned in the bore such that the head rests against the shoulder. The lip is then deformed to overlie the upper surface of the head and permanently join the two members.
Additional objects and advantages of the present invention will readily suggest themselves to one skilled in the art from the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view showing an obturator of the present invention partially inserted into a catheter;
FIG. 2 is an enlarged side elevational view, partly in section, illustrating the stem and hub of the obturator prior to their assembly;
FIG. 3 is an enlarged top plan view of the stem and hub after the initial assembly operation;
FIG. 4 is a view taken along the line 4-4 of FIG. 3 but also showing a portion of the deforming plunger;
FIGS. 5 and 6 are views similar to FIG. 4 but showing subsequent steps in the assembly operation.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, the obturator of the present invention is illustrated generally at 10. In FIG. 1, the obturator 10 is shown partially inserted into a mating catheter 15.
The obturator 10 comprises an elongated flexible plastic stem 12 which is securely joined to a plastic hub 20 in a manner hereinafter further described. The catheter 15 is generally conventional and may include a clear plastic tube 16 which is fused or otherwise joined to a terminal connector 17. The stem 12 is designed to enter the bore of the tube 16 and occupy substantially the full diameter thereof to occlude the catheter. By reason of this fact, the stem effectively prevents clotting of the blood or other fluid in the bore when the catheter is permitted to remain in position within the body.
The stem 12 and hub 20 may be formed from any suitable plastic material which is easily molded or formed by conventional equipment. Examples of suitable materials would be polyethylene, polypropylene, tetrafluoroethylene, and the actel polymers sold under the trade names Delrin by Du Pont and Celcon by Celanese Corporation of America.
FIGS. 26 illustrate the manner in which the stem 12 is joined to the hub 20. As shown in FIG. 2, the stem 12 is in the form of a cylindrical rod having an enlarged head 13 formed at one end and a rounded nose 14 at the opposite end. The hub 20 includes a tubular body 21 which is designed to receive and retain the head 13 of the stem. The bore of the tubular body 21 includes a reduced diameter portion 22 which is only slightly larger than the diameter of the stem, and an enlarged diameter portion 23 which is somewhat larger than the maximum diameter of the head 13. A tapered shoulder 24 is provided at the juncture of the two bore portions and is shaped to generally conform to the lower surface of the head 13. An upwardly directed annular lip 25 is formed at the end of the enlarged diameter portion opposite the shoulder 24 for the purposes hereinafter set forth.
The stem 12 is initially positioned in the bore of the body 21 as illustrated in FIG. 4. A plunger 30, which may be heated to facilitate flow, then deforms the lip 25 such that it overlies the upper surface of the head 13 as shown in FIG. 5. The lip 25 and plunger 30 may be dimensioned such that only the material from the lip is deformed to overlie the head or they may be dimensioned such that a portion of the bore wall at the enlarged diameter portion 23 is also deformed. Thus, by choice in design, the head 13 may be only partially covered as shown in FIG. 5, or completely covered as shown in FIG. 6.
The hub 20 may be secured and locked to the tubular terminal connector 17 of the catheter by a standard Luer-Lok connection. In this instance, the hub 20 includes a circumferential flange 27 which is integrally connected to the top end of the body 21 (note FIG. 2). The flange is spaced from the body to form an annular opening 28 for receiving the terminal connector 17. The internal surface of the flange may include female threads 29 which are adapted to engage an appropriately threaded external rib 18 upon entry of the terminal connector into the opening 28. By this arrangement, the obturator may be easily attached to and detached from the catheter.
The stem 12 may, if desired, be made radiopaque. In the unlikely event that the stem should break or become dislodged from the hub 20 and subsequently find its way into a vein or other cavity in the body, the stem could then be easily located by radiographic examination.
While a specific embodiment of the invention has been described in some detail herein, it should be understood that the scope of the invention is to be deter mined by that of the appended claims only.
What is claimed is:
1. A disposable, plastic obturator adapted to close the end of a catheter comprising:
an elongated, flexible plastic stem having a diameter substantially the same as that of the bore of said catheter, an enlarged head at one end of said stem; and a blunt tip at the opposite end;
a hub of separate plastic material including a body portion closely surrounding both said head and the adjacent portions of said stem; and,
means to permanently secure said head in said body,
said means including a shoulder in said body at the side of said head closest said blunt tip and a deformed lip covering the other side of said head wherein said head is totally encapsulated by and se- 4 curely maintained in position between said shoulder and said lip whereby said stem is prevented from being separated from said head by a force applied either toward or away from said tip. 2. The disposable plastic obturator as defined in claim 1 wherein the stem is radiopaque.
3. The disposable plastic obturator as defined in claim 1 wherein said hub further includes an integral circumferential outer flange which is spaced from said body portion to form an annular opening therebetween for receiving the terminal connector of a catheter.
4. In combination, a surgical catheter and a disposable obturator having portions disposed within and occluding the bore of said catheter; said catheter comprising a tubular member having a terminal connector at one end, said connector being substantially tubular and having an external rib at an open end thereof; and said disposable obturator comprising an elongated, flexible plastic stem having a diameter substantially equal to the diameter of said catheter bore, an elongated head at one end of said stem and a blunt tip at the opposite end; a hub of separate plastic material including a body portion closely surrounding both said head and the adjacent portion of said stern; and means to permanently secure said head in said body, said means including a shoulder in said body at the side of said head closest said blunt end and a deformed lip covering the other side of said head wherein said head is totally encapsulated by and securely maintained in position between said shoulder and said lip whereby said stem is prevented from being separated from said head by a force applied either toward or away from said tip; said hub including a circumferential flange which is concentric to the axis of said stem to form an annular opening between said stem and said hub, said opening being adapted to receive said terminal connector; and, locking means positioned in said opening to engage said external rib on said terminal connector.
References Cited UNITED STATES PATENTS 1,564,499 12/1925 Tropp 128221 1,569,453 1/1926 Brody 128-221 3,406,685 10/1968 May 128214.4 3,469,579 9/1969 Hubert 128214.4
DALTON L. TRULUCK, Primary Examiner US. Cl. X.R. 128-348