Catheter with electrical cutting means

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic illustration of the catheter of the present invention shown with a conventional electrosurgical apparatus and illustrated in an operative position for use with a person.

FIG. 2 is an elevational view of the catheter shown in FIG. 1 partially in section to more clearly illustrate the forward end thereof.

FIG. 3 is a fragmentary perspective view of the catheter illustrated in FIGS. 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Illustrated in FIGS. 1—3 is the catheter 10 of the present invention which comprises a suitable flexible tube 15 made of rubber, plastic or the like and an obturator 20 in the form of a rod-shaped electrical conductor or electrode.

The catheter tube 15 is formed at the distal end thereof with a plurality of elongated, axially disposed drainage openings 16 suitable for the drainage of fluids and the like. At the distal end of the catheter tube 15 is also located a ring or eyelet 17, which is intended to be sufficiently rigid and strong to withstand applied force and is made of suitable material such as stainless steel or a high-tensile plastic.

Removably disposed within the catheter tube 15 is an obturator or rod 20 in the form of an electrical conductor or an electrode. The obturator 20 is basically of a metal wire-type construction, flexible, but more rigid than the catheter tube 15. Specifically, the obturator 20 comprises a solid cylindrical body 21. At the distal end of the body 21, the rod 20 includes a cylindrical tip 22 that is tapered to a sharp needlelike point. The body 21 is made of suitable material, such as stainless steel and the sharp tip 22 is made of suitable material, such as tungsten or tungsten-coated steel, or other suitable noncorrosive, electrically conductive material.

A cylindrical member 23, such as a ring or a sleeve, of the rod 20 surrounds the body 21 to form a shoulder 24 at the junction with the tip 22. Surrounding the body 21 rearward of the ring 23 is a tubular insulator 25 made of suitable material, such as Teflon.

At the proximal end of the obturator 20 is disposed a tubular insulator 30 made of suitable material, such as Teflon. Rearward of the sleeve 30 is located an electrical terminal connector 35 for the obturator 20, which may be in the form of a receptacle or a plug for establishing an electrical connection with a conventional and well-known electrosurgical apparatus 40, which produces high frequency currents and is a source of high frequency electrical energy.

The insulator 30 extends to the connector 35 and projects into the catheter tube 15 when the obturator 20 is fully inserted in the catheter tube 15. When the obturator 20 is fully inserted into the catheter tube 20, the catheter tube 15 serves as an insulator for the obturator 20 between the tip 22 thereof and the uninsulated portion ofthe body 21.

When the obturator 20 is placed into the catheter tube 15, the tip 22 of the obturator 20 extends beyond the ring or the eyelet 17 of the catheter tube 15 and the extent ofthe projection of the tip 22 out of the distal end of the catheter tube 15 is limited by the engagement of the shoulder 24 of the obturator 20 against the ring 17 of the catheter tube 15. The eyelet 17 is of sufficient rigidity and strength as to preclude excessive passage of the tip 22 out of the distal end of the catheter tube 15 and to withstand the force applied to the obturator 20 by an operator. The Teflon sleeve 25 serves to reduce leakage of electrical current through the ring 17 and through the drainage openings in the catheter tube 15 by reducing arcing at the ring 17. Also, it reduces coagulation occurring in the vicinity of the ring 17.

In the typical embodiment of the catheter 10, the length of the obturator 20 is 18 inches and the diameter ofthe body 21 is one-sixteenth of an inch. The ring 17 ofthe catheter tube is of sufficient dimension to pass the maximum width of the tip 22 of the obturator, which is one-sixteenth of an inch. The tip 22 of the obturator 20 projects approximately one-fourth of

CATHETER WITH ELECTRICAL CUTTING MEANS

BACKGROUND OFTHE INVENTION

The present invention relates in general to catheters, and ⁵more particularly to a catheter in which an obturator-electrode performs the function of producing a path for electrical energy to divide or cut tissue of a body for forming a passageway through which a catheter tube advances.

Catheters of the suprapubic type have, heretofore, been placed through the abdominal wall into the urinary bladder by several procedures. One commonly employed procedure is open surgery, in which the abdominal wall is actually opened surgically. In this procedure, an opening is also cut into the urinary bladder and the catheter is sewn in place into the bladder. This procedure is considered to be major surgery.

Another method involves the pushing of a catheter through the abdominal wall into the urinary bladder in a manner similar to inserting a needle in a vein. This method employs a 20 large trocar which is sufficiently large for a catheter tube to pass through its lumen and into the urinary bladder.

The first procedure is not desirable, since it requires an open operation and is considered to be major surgery. The second procedure requires the insertion of a trocar into the 25 tissue of a body with the application of substantial force. This action may cause a disruption of the urinary bladder or surrounding structure. It may be difficult at times to pass a catheter through the abdominal wall by this procedure when earlier surgery has been performed and there is a firm scar tis- 30 sue in the area intended to receive the catheter.

The trocar which is urged into the bladder through this procedure is always larger than the catheter advancing through its lumen. This action results in a relatively large opening in the bladder defining a relatively large space around 35 the catheter when the trocar is removed. As a consequence thereof, there is commonly present a leakage of urine from the bladder through the space around the catheter, which may cause an abscess or an infection, and, also, may produce a tendency for excessive bleedings. 40

SUMMARY OFTHE INVENTION

The catheter of the present invention employs a removable obturator-electrode to define an electrical path for electrical 45 energy to divide or cut tissue of a body for forming a passageway through which a catheter tube advances. Through this arrangement, the size of the passageway receiving the catheter tube is accurately controlled and the catheter tube can be advanced into the cut or divided tissue with a reduced 50 application of force.

By virtue of this procedure, the passageway for the catheter tube is formed at the smallest possible size to minimize injury to the body and to reduce leakage of fluid around the catheter tube. As a consequence thereof, abscesses and infections are 55 reduced. Also, the catheter tube can be advanced into the passageway with reduced applied force. Thus, the catheter tube advances into the passageway without disruptive force and the catheter tube can now be advanced into a cavity in the tissue of a body, although a dense scar tissue is present in the 60 area receiving the catheter tube.

With the size of the passageway accurately controlled for receiving the catheter tube, the tissue ofthe body fits snugly or tightly around the catheter tube. As a result thereof, there is a compression of blood vessels and a lessening of excessive 65 bleedings.

While electrical energy performs a dividing or cutting ofthe body tissue operation, it also performs a coagulating function to seal off bleeding vessels and to prevent excessive hemorraging. Thus, there is a coagulation of bleeding vessels to reduce 70 subsequent hemorrage from the advancement of the catheter tube.

Other and further objects and features of the present invention will appear upon further perusal of the detailed description taken in conjunction with the accompanying drawings. 75

3,595,239 an inch to three-eights of an inch beyond the distal end of the catheter tube, when the shoulder 24 engages the ring 17 of the catheter tube 15. The shoulder 24 is brazed or welded to the body 21 or may be integrally formed therewith. The exemplary dimension for the shoulder 24 is three thirty-seconds of an inch in diameter. The sleeve 25 is preferably of 1 inch to 2 inches in length and has a thickness of one sixty-fourth of an inch.

One side of the electrical output of the electrosurgical apparatus 40 is connected to the obturator 20 through the connector 35. The other side of the electrical output for the electrosurgical apparatus 40 is connected to a conductor plate electrode 41 upon which rests the body P of the patient. The electrode 41 is in spaced relation with the tip 22 of the obturator 20.

The obturator 20 is an electrode and serves as a conductor for high frequency currents. High frequency electrical energy between the electrode 41 and the tip 22 of the obturator 20 cuts or divides tissue of the body at the tip 22. This action results in the formation of a passageway in the body tissue for the advancement of the catheter tube 15. The catheter tube 15 is capable of advancing in the passageway with a reduced application of force. The catheter tube 15 follows behind the tip 22 of the obturator in advancing into the passageway. Further, the high frequency energy at the tip 22 of the obturator 20 has a coagulating effect, as well as a cutting effect, which seals off bleeding vessels and reduces hemorraging.

While the present invention shows a balloon-type catheter tube, the inventive concept hereof is equally applicable to catheter tubes of many types and shapes, such as straight simple catheter tubes, mushroom-type catheter tubes, and Mellecott catheter tubes.