Postsurgical Tubes With Capped Proximal End

Abstract

Thoracic catheters and similar postsurgical drainage tubes are made with a proximal end unit which forms an end closure to maintain sterile conditions and to provide forceps grasping means during patient insertion procedures. Following placement in the patient, the closed tip of the proximal end is cut off to permit fluid flow through the tube.

Description

BACKGROUND OF THE INVENTION

The present invention relates to medicosurgical tubes with capped proximal ends. More particularly, it is concerned with improved catheters and equivalent tubes which are used for drainage procedures involving placement of the catheter in the patient by drawing the proximal end through a secondary incision in the patient made for this purpose.

Intercostal catheters and equivalent medicosurgical tubes are utilized with surgical operations for postsurgical drainage purposes to remove fluids and other matter from body cavities of the patient. The intercostal catheters and similar postsurgical drainage tubes are positioned in the patient at the completion of the surgical operation by insertion through the original incision with the proximal end portion of the catheter entering the incision ahead of the distal end contrary to the more normal placement of a catheter where the distal end first enters the patient. A second incision or stab wound is made in the patient and forceps are inserted through it to grasp the proximal end of the catheter. The catheter is pulled into the body until the distal end portion is properly positioned with the tube leading out through the second incision. The catheter placement procedure is completed by connecting the proximal end to necessary auxiliary drainage equipment, e.g., an underwater seal.

The reverse method of installing intercostal catheters with the proximal end portion first entering the patient and then again being withdrawn is employed by surgeons to safeguard against contamination of the pleural area or other body region from which materials are to be withdrawn through the catheter. However, this system of catheter installation creates problems which can lead to ripping or tearing of body tissue as the proximal end of the catheter is drawn to and through the second incision or stab wound. A so-called coring effect can occur which will lodge body tissue in the lumen of the proximal end portion of the catheter. These difficulties associated with use of postsurgical drainage tubes are well known to the medical profession and various modifications in drainage tube construction have been proposed to mitigate the problems (see U.S. Pat. Nos. 3,190,290 and 3,295,527).

In addition to the slanted or fusiform ends for medical catheters as proposed in the aforementioned patents, a variety of other end constructions have been proposed in the past in the construction of catheters. Such proposals have included a "duckbill" end for a catheter with two opposed branches which may be closed by compression to form a conical or wedge shape upon the end of the catheter during its passage into a body channel or cavity (see U.S. Pat. No. 217,711). Notwithstanding all of these prior ideas for catheter improvement, more is needed to insure the safe and efficient utilization of intercostal catheters or equivalent postsurgical drainage tubes as a part of successful surgical operation upon a patient.

OBJECTS

A principal object of this invention is the provision of new improvements in the proximal end portion of medicosurgical tubes.

Further objects include the provision of:

1. Postsurgical drainage tubes of improved construction having nontraumatic proximal ends which permit smooth installation in a patient without ripping, coring or tearing of body tissue of the patient.

2. Improved drainage catheters which prevent material from entering the interior until the catheter is properly positioned and ready for connection of the proximal end to auxiliary drainage equipment.

3. New proximal end portions for catheters that permit surgical forceps to obtain a sure, firm grip upon the proximal end of the catheter and insure satisfactory movement of the catheter through body tissue during patient placement.

Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description, while indicating preferred embodiments of the invention, is given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. It should also be understood the foregoing abstract of the disclosure is for the purpose of providing a nonlegal brief statement to serve as a searching-scanning tool for scientists, engineers and researchers and is not intended to limit the scope of the invention as disclosed herein nor is it intended it should be used in interpreting or in any way limiting the scope or fair meaning of the appended claims.

SUMMARY OF THE INVENTION

These objects are accomplished according to the present invention by constructing medicosurgical tubes of flexible plastic material to include a distal end portion comprising at least one fluid opening, a proximal end portion and a central body portion integrally joining the distal end portion to the proximal end portion, the tubes being characterized by the proximal end portion being closed by a tapered closed tip. In a preferred embodiment, the closed tip is provided by a closed cap that is fixed to the tube with the closed cap having an elongated cylindrical portion which tapers to a closed tip.

Advantageously, the closed cap defining the proximal end of the drainage tubes is molded of plastic material such as by injection molding, dipping, plastisol molding, dielectric molding or other suitable molding procedure known to the plastics art. Such molded closed cap is affixed by cement, by fusion or other suitable means to the end of the drainage tube. This closed cap may be molded of flexible, semirigid or rigid plastic material while the remainder of the tube is advantageously formed of flexible plastic material and desirably of transparent plastic material. Fabrication of the medicosurgical tubes from the flexible plastic material is advantageously accomplished by extrusion although dipping or other fabrication techniques may be employed.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a fragmentary side elevational view, partially in section, of the proximal end portion of the embodiment of a postsurgical drainage tube in accordance with the invention.

FIG. 2 is a fragmentary top elevational view of the proximal end portion of the embodiment of the invention illustrated in FIG. 1.

FIG. 3 is a fragmentary side elevational view of the proximal end portion of the embodiment of the invention illustrated in FIG. 1 being gripped between jaws of surgical forceps. FIG. 4 is a fragmentary perspective view of a postsurgical drainage tube in accordance with the invention showing the distal end portion and the proximal end portion.

FIG. 5 is a fragmentary perspective view similar to FIG. 4 showing another embodiment of postsurgical drainage tube of the invention with the nontraumatic proximal end partially cut off in preparation for connection to auxiliary drainage equipment.

FIG. 6 is a top elevational view of the proximal end portion of a different form of postsurgical catheter.

FIG. 7 is a side elevational view of the proximal end portion of the catheter illustrated in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1 through 5 illustrate preferred embodiments of medicosurgical tubes in accordance with the invention. In order to illustrate in as large scale as possible within the limitations of the accompanying drawing, the distal end portion of the new drainage catheters is not shown in FIGS. 1--3 and the central body portions are not shown in FIGS. 4 and 5. Generally, the distal end portion will involve an open end tip and a plurality of side inlet openings (see U.S. Pat. No. 3,190,290). Additionally, the new catheters may include an X-ray line (see U.S. Pat. No. 3,295,527) or other suitable imprinted or infused X-ray opaque inlet perimeters, tube portions or the like designed to aid the surgeon, physician or other person attending the patient to determine location of any desired section of the catheter within a body cavity or channel in the patient.

Referring in detail to FIGS. 1--3, the drainage tube 2 has a proximal end portion 4 which is integrally joined to a central body portion 6 which constitutes the major longitudinal extension of the catheter. Normally, the central body portion 6 will constitute an extruded flexible plastic tube of uniform diameter and wall thickness. However, if dictated by preference of the surgeon using the catheter or other special requirements, the body portion can be formed with variations in wall thickness, tapered sections or the like using pressure blowing, vacuum drawing or other techniques known to the plastics art.

The closed cap 8 has an elongated cylindrical portion 10, a tapered section 12 and a closed tip 14. The closed tip might be described as a closed duckbill. It presents a semielliptical perimeter 16 comprising one side 18, an arcuate end 20 and another side 22. It further comprises a top face 24 and a bottom face 26. The width of the closed tip 14 measured between the sides 18 and 22 is longer than the depth measured between the top face 24 and the bottom face 26. As can be seen from FIGS. 1 and 2, no portion of the closed tip 14 has a dimension transverse to the longitudinal axis of the cylindrical portion 10 as great as the outside diameter of the portion 10 i.e., the maximum transverse dimension of the closed tip 14 is between the sides 18 and 22 and this is not as great as the outside diameter of portion 10. The generally flat surfaces of the top face 24 and the bottom face 26 provide means by which surgical forceps 28 may firmly grip the closed cap 8 when it becomes necessary for the surgeon to withdraw the catheter through body tissue and a second incision in the patient in accordance with established procedures for installation of intercostal catheters.

In the form of catheters shown in FIGS. 1--3, the elongated cylindrical portion 10 of the closed cap 8 is of substantially uniform cross section and inside diameter. This inside diameter is substantially equal to the outside diameter of the proximal end tube portion 30. Consequently, the closed cap 8 forms an overlap joint with the tube end portion 30 and is affixed to the tube by cement. Alternatively, solvent which will soften the plastic of the tube or the molded cap or both may be used to fix the cap to the tube or electronic welding or any other equivalent fabrication technique may be used to unite the molded cap 8 to the tube end portion 30. As an alternative, the closed cap 10 can be molded with a stepped or recessed end so that the tip 32 of the tube would butt against a radial face molded in the closed cap 10. As a further modification, the cylindrical portion 10 of the cap could be of the same inside and outside diameter as the tube tip 32 with these separate parts being joined by a butt joint formed by friction welding, cementing or equivalent method of attachment.

In use, the catheter will be led through the major incision formed in the patient during the surgery by leading the closed tip 14 into the incision to be followed by the cylindrical cap portion 10 and then the tube body portion 6. A second incision or stab wound is also made in the patient according to established surgical practice, the surgical forceps 28 will be inserted through the second incision until the tip 14 within the patient body cavity can be grasped as shown in FIG. 3. The proximal end portion of the catheter may then be withdrawn from the patient's body without any tearing, ripping or coring of body tissue. Such withdrawing of the proximal end will continue until the distal end assumes the required position within the body cavity or channel as determined by suitable procedure known to the medical profession. An anchor stitch through the skin of the patient adjacent the second incision or equivalent method will be applied to insure that the catheter is retained in this critical position in the patient. During all of this manipulation, the closed cap maintains the interior of the catheter sterile until the moment when the surgeon determines the time has arrived to attach the catheter at the proximal end to auxiliary drainage equipment. To accomplish this, the end of the closed cap 10 can be severed with a scissors at the junction 34 between the cylindrical portion 10 and the base of the taper portion 12. This will permit the use of a connector with a lumen size equal to or larger than tube 6 to the auxiliary drainage equipment, facilitating "milking" of blood clots or other possible solid obstructions in the tube if this should become necessary during the postsurgical drainage procedure.

In the embodiment of the invention shown in FIG. 4, the intercostal catheter 2a comprises a proximal end portion 4a, a tube 6 and a distal end portion 40. The nontraumatic closed cap 8a has a closed tip 14a joined to an elongated cylindrical portion 10a by a tapered section 12a. The closed tip 14a is oval in cross section and provides means by which forceps may securely grasp the catheter during the placement procedure.

The closed cap 8a is joined by an overlap joint to the tube 6 and is secured by solvent welding or its equivalent. Since the closed cap has an inside diameter equal to the outside diameter of the tube 6, the bore of the tube 6 continues at full size clear to its end. This permits a connection to be made at the proximal end giving full lumen drainage to the catheter. The distal edge 42 of the cap 8a may be beveled as shown to provide the maximum of smooth flow and easy, nontraumatic passage through body tissue of a patient.

The distal end 40 of the catheter has a rounded tip 44 made of a fused ring of X-ray opaque plastic material. An inlet opening 46 enters through the tip 44. The catheter is also provided with side entering inlet eyes 48 which are generally from three to five in number depending on the catheter size.

In the embodiment of the intercostal catheter 2b shown in FIG. 5, the tube 6 has a cap 8a which has been cut off after placement in the patient leaving an open end. The bore of the catheter 2b is packed by a slightly compressed rod 52 of plastic foam which extends from the distal end opening 46 along the entire length of the tube bore and into the cap 8a. With the closed end of the cap cut off, the proximal end 54 of the plastic foam rod 52 becomes available to the surgeon permitting the rod 52 to be withdrawn to open the full lumen of the tube to drainage through the inlet openings 46 and 48. The plastic foam rod packing in the catheter 2b provides means to prevent blockage of the tube by blood clots or other solid matter during the procedure of placement of the catheter in the patient as disclosed in copending application of Sheridan, filed Feb. 19, 1969, as Ser. No. 800,547, and entitled "Insured Internal Flow Medicosurgical Tubes."

The closed caps of the new drainage catheters can be molded in any of the standard sizes of thoracic catheters such as French size 16 through 40 and the flexible tube comprising the central portion and the distal end portion may be of any required length such as the usual 20-inch length. Further, the catheter may be formed with a straight central body portion of with a right angle proximal to the drainage inlets or eyes as required by certain postsurgical drainage procedures. Advantageously, each individual catheter will be enclosed in a separate package or envelope, sealed and then sterilized in known fashion by ethylene oxide vapor exposure, gamma ray irradiation or the like in order to sterilize the package and catheter. When marketed in this manner, each individual catheter is ready for immediate use without requiring sterilization. Formulation of the plastic material from which the postsurgical drainage tube is extruded can be controlled as is known in the art to give tube flexibility at body temperatures while maintaining necessary wall strength so that the catheter will conform adequately to the contours of the body cavity or channels to which it extends within the patient. Marker rings or other length indicia may be printed on the outside wall of the tube 6 at required locations to aid the surgeon in determining the location of the most proximal inlet opening or eye along the distal end portion of the catheter. Skilled users of the catheters may use such markings in lieu of X-ray examination to determine position of the distal end portion of the catheter within the patient

ADDITIONAL DISCLOSURE

Another form of catheter end which may be used in construction of intercostal catheters is illustrated in FIGS. 6 and 7. In this form of catheter 40', the proximal end portion 42' comprises an upper wedge shape lip 44' and a lower complementary shaped lip 46'. Rounded tips 48' are formed on each of these lips and side edges 50' and 52' are provided with inwardly extending bevels 54'. The lips 44' and 46' are compressed together as shown in FIG. 7 and fixed in this position by cement, heat fusion or in equivalent manner. This serves to reduce ripping or tearing of body tissue when a drainage catheter of this form is positioned within a patient according to the established procedure as described previously. When the catheter has been properly installed, the proximal end of the catheter may be opened by cutting along the seam line 56' forming an open mouth end which serves as connector means for joining the catheter to the required tubes or equipment. The joined lip construction of these catheters provides a stiffer end than the remainder of the tube during the placement procedure which aids in the installation and grasping of the tip by forceps. Also, the open lip arrangement which results when the lips are separated after placement gives a flexibility to the proximal end that permits an absolutely airtight connection to be made to auxiliary drainage equipment. As is known in the use of thoracic catheters no leaks of any kind can be tolerated in the drainage system.

Claims

We claim:

1. A postsurgical drainage tube in which the lumen of the proximal end can remain sterile throughout placement of the tube in a patient and until the tube is prepared for fluid flow therethrough formed of nonfibrous plastic material comprising a distal end portion, at least one fluid opening in said distal end portion, a proximal end portion, a central body portion joining the distal end portion to the proximal end portion, and a closed cap on said proximal end, said closed cap having an elongated cylindrical portion which tapers to a closed tip, said cylindrical portion having an outside diameter at least equal to the outside diameter of said proximal end, said closed tip having an arcuate perimeter, no portion of said closed tip having dimension transverse to the longitudinal axis of said cylindrical portion as great as said outside diameter.

2. A postsurgical drainage tube of claim 1 which is an intercostal catheter.

3. A postsurgical drainage tube of claim 1 wherein said closed tip has a width longer than its depth.

4. A postsurgical drainage tube of claim 1 wherein the inside diameter of said cylindrical portion is substantially equal to the outside diameter of said proximal end and said closed cap is joined to said proximal end with an overlap joint.

5. A postsurgical drainage tube of claim 1 wherein said outside diameter is substantially equal to the outside diameter of said proximal end and said closed cap is joined to said proximal end by a butt joint.

6. A post surgical drainage tube of claim 1 wherein said tube is formed of flexible transparent plastic material and said closed cap is formed of semirigid plastic material.