IL30337A

IL30337A - Catheters

Info

Publication number: IL30337A
Application number: IL30337A
Authority: IL
Original assignee: Dow Corning
Priority date: 1967-11-16
Filing date: 1968-07-09
Publication date: 1971-06-23
Also published as: IL30337A0; SE351982B; FR1591544A; GB1218597A; NL6816289A; DK120167B; BE723883A; AT287176B; NO117876B; US3508545A; NL144487B; DE1800361A1

Description

CATHETERS DOW CORNING CORPORATION The present invention relates to catheters.

There is frequently a necessity to administer patenteral solutions continuously or inte mittently to patients over a relatively long period of time. In such cases, the common practice has been either to puncture the patient's flesh or vein with a metal hypodermic needle and leave the needle in place over the required period or to cut surgically into the flesh or vein with a scalpel, insert a flexible plastic tube, and suture the opening to hold the tube in place over the required period. Both of these practices present difficulties. For example, when a metal hypodermic needle is left in the patient over an extended period of time, the patient must be immobilized to prevent the point of the in-dwelling needle from accidentally damaging the surrounding tissue. Should such an accident happen, another puncturing of the flesh or vein of the patient and a reinsertion of the needle would be required, resulting in additional pain and discomfort to the patient. Further, continued immobilization of the parts of the patient's body might cause the patient severe discomfort.

More recently, a new technique has been developed which involves puncturing the flesh or vein of a patient with a sterile hollow needle and then threading a sterile, flexible plastic catheter into the flesh or vein. The needle is then removed and the catheter allowed to remain in place as long as desired. . However, this new technique In some instances the catheter is guided through the hollow needle with a stylet, which creates the possibility of perforating the vein wall when the catheter is advanced.

Other catheters have curls or hooks at their inserted ends which also require the insertion and removal to be carried out. with a stylet, and these catheters frequently cause damage to the mucosa of the patient when they re -curl after the stylets are removed. Such catheters must be inserted relatively deep into the patient's flesh in order to adequately secure them. In addition, some heretofore known devices use split or slotted needles, which create a danger of an accumulation of an intraluminal plug of tissue upon insertion of the needle, interfering with, the ultimate advancement of the catheter through the needle.

The present invention provides a catheter placement unit, preferably made of silicone rubber, and consisting of a tubular guide, an introducer needle having at one end a slotted trocar for puncturing the flesh or vein of a patient, and a catheter which has a flexible tube having adjacent one end a resilient bar -shaped protuberance. The guide provides a means for accurately placing the catheter, while the introducer needle punctures the patient's flesh or vein and also carries the catheter to the injection site. The resilient barb-shaped protuberance fits through the slot in the trocar and proves a means for holding the catheter in place after the guide and Introducer needle are withdrawn. The resilient barb -shaped protuberance further provides a means by which the catheter may be carried to the injection site by the introducer needle, thereby eliminating the catheter is made of flexible silicone rubber, the patient need not be immobilized after its insertion, as there is no danger of accidental puncture from such a flexible catheter. Further, the possibility of damage and danger to the patient are minimized .

The invention is further illustrated with reference to the accompanying drawings, in which: Figure 1 is a view in elevation showing the tubular guide of the present invention pressed against a cross -section of any fleshy surface; Figure 2 is a view in elevation showing the introducer needle of the present invention; Figure 3 is a side view in elevation showing the cathetor of the present invention inserted in a cross -section of any fleshy surface; Figure 4 is a side view in elevation showing the catheter plaoement unit of the present invention inserted in a cross -section of any fleshy surface; Figure 5 is a cross -se ctional view of a variation of the catheter placement unit of the present invention showing the tubular guide pressed against a cross -se ction of any fleshy surface; Figure 6 is a -view in elevation of the embodiment of Figure 5 v/ith the needle inserted in a cross -section of any fleshy surface; and Figure 7 is a view in elevation of the embodiment of Figures 5 and 6 showing the catheter embedded in the flesh and the tubular guide and needle withdrawn.

Referring now to the drawings wherein like reference - the figures thereof, there isshown in Figure 4, a catheter placement unit shown generally as 10.. While it is to be understood that the catheter placement unit 10 can be used generally as any other catheter can be used, one use for which the catheter placement unit of the present invention is particularly suited is in a continuous paracervical anesthesia administration system. This is true because of the near impossibility of immobilization of the pertinent areas of a mother's body during childbirth and because of the obvious danger to the mother and child inherent in the insertion and continuous use of long and sharp hypodermic needles in the cervix of the mother during childbirth.

In a continuous paracervical anesthesis administration system, two catheters are inserted, preferably one at the 2-4 o'clock position and one at the 8--10 o'clock position in the patient's lateral fornix. The tubular guide 11, shown in Figure 1 and made of some suitable plastic or rubber material , is placed against the vaginal mucosa in the patient's laterial fornix at either of the desired positions as is illustrated by the fleshy surface 12 in Figure 1.

The introducer needle, shown generally as 13 in Figure 2, has already had the catheter, shown generally as 14 in Figure 3, threaded through it prior to the beginning of the anesthesia administration. The needle 13 consists of a tube 15 having an outwardly extending radial enlargement 16 at one end and a trocar 18 which is slotted as can be seen at 20 in Figure 2. The tube 15 is also made of some suitable plastic or rubber material, and the slotted trocar is preferably made of stainless steel.

X 13 consists of a flexible silicone rubber tube 22 which has a resilient barb-shaped silicone rubber protuberance 24 adjacent one end . The catheter 14 and the proturberance 24 are preferably made of silicone rubber because of its inertness to the human body and its softness and pliability, which allows the catheter 14 and protuberance 24 to pass through the vaginal mucosa or any other fleshy surface without causing trauma.

When the catheter 14 is fully threaded through the needle 13, the .resilient protuberance 24 fits through the slot 20 in the trocar 18, as may best be seen in Figure 4.

Thus, as shown in Figure 4, when the needle 13 Ϊ3· passed through the guide 11 until the radial enlargement 16 contacts the upper end of the guide 26, the catheter 14 is carried to the injection site in the vaginal mucosa by the trocar 18 pushing against the protuberance 24.

Obviously, the radial enlargement 16 serves to stop the needle 13 at a predetermined desired puncture depth, generally about 1 centimeter. Thus, the catheter of the present invention may be used to male desirable superficial injections. Such superficial injections cannot be made by catheters having a hook or curve at their inserted ends, since they must be inserted reMiively deep in the patient's flesh in order to adequately secure them.

When the guide 11 and needle 13 are then withdrawn, the catheter 14 remains in the vaginal mucosa shown as 12 in Figure 3. A catheter adapter is then inserted into the ends of the catheter outside the patient's body. If a bloody tap is encountered, the catheter is withdrawn and 13 is then ready for use and may simply be taped to tte mother's abdomen for continuous or intermittent injections of an anesthetic fluid as required.

Finally, the catheter is either dislodged with the delivery of the child or by a mild pull or traction on the catheter after the delivery of the child . Thus , no ^instrumentation is required to remove the catheter from the patient .

The resilient barb-shaped protuberance 24 clearly has two functions. Firstly, the protuberance provides a means by which the catheter 14 may be carried to the injection site by the introducer needle 13. Thus, the dangers and difficulties prior art devices presented by requiring the forcing of a catheter, usually with a stylet, through the introducer needle are eliminated. Further, the possibility of the slotted needle accumulating an intraluminal plug of tissue which would interfere with the insertion of a catheter through the needle is obviated by the presence of the. protuberance 24 in the slot of the trocar 18 upon its insertion.

Secondly, the protuberance functions as a means for holding the catheter in the patient once it has been inserted, thereby preventing accidental displacement of the catheter. A silicone rubber is preferred for the catheter and protuberance because. it is flexible, sterilizable , and inert to the human body. Further, the silicone rubber protuberance presents a resilient material upon which the flesh can take hold and roleasably secure the catheter in place . Other materials , such as polyethylene and poly- l more ri id tend longer needed. The protuberance of the present invention reloasably secures the catheter in place without need of being deeply inserted into the flesh and without scratching or damaging the mucosa of the patient.

Thus, due to the flexibility of the catheter tube and the protuberance the immobilization of the patient required by prior art devices is eliminated. -In fact, when the catheter of the present invention is used in a paracervical anesthesia system, the expectant mother is completely ambulatory between the time the catheters are inserted and the actual delivery of the child begins .

In one specific embodiment of the present invention, the tubular guide was made of polypropylene, was 21.6 cm. long, with an outer diameter of 0.554 cm. and an inner diameter of 0.437 cm. The introducer needle was 28.13 cm. long. The slotted trocar was made of stainless steel and the tube was made of polypropylene. The length of the radial enlargement was 5.08 cm. and its outer diameter was 0.554 cm. The length of the tube, Including the radial enlargement, was 26.67 cm. The inner diameter of the tube was 0.165 cm. and the outer diameter of the tube was 0.371 cm. The trocar was a 17 gauge needle and was 1.46 cm. long. The slot had a width of 0.096 cm. and a height of 0.554 cm. The catheter tube was 40.64 cm. long and the barb-shaped protuberance had a width of 0.676 cm., a depth of 0.089 cm. and a height of 0.267 cm. Both the catheter tube and protuberance were made from silicone rubber.

There is shown in Figure 5 a variation of the catheter placement unit of the present invention, shown generally in this variation. The introducer needle 13 is shown in Figure 2 has been modified , so. that the outwardly extending radial enlargement 16 forms a knob or handle 16' as can be seen in Figure 5. The tubular guide 11 shown in Figure 1 has also been modified to include an outwardly extending radial enlargement 31 at one end. This enlargement has within it a groove or slot 32 into which a spring 34 may fit and rest upon its lower lip. The enlargement also has within it another groove 36 into which at least a portion of the introducer needle handle 16' may be freely inserted .

The introducer needle is permanotly inserted into the tubular guide at the time of manufacture in this variation. Thus, the lower edge of the introducer needle handle 16' can freely move axially in the grove 36, but its axial movement is stopped by both the upper and lower lips of that groove. The spring 34 rests. on the lower lip of the groove 32 and biases the lower edge of the introducer needle handle .1.6' against the upper lip of the groove 36, when there is no axial force being exerted inwardly on the handle. When the introducer needle is in this position, the slotted trocar 18 is wholly within the tubular guide, as can be seen in Figure 5. Obviously, when the catheter 14 is threaded into the introducer needle, the barb-shaped protuberance 24 is also wholly within the tubular guide 11. The catheter may be threaded at the time of manufacture of the catheter placement unit or just prior to its use.

When an inward axial force is exerted on the introducer needle handle 16' by pressure from a doctor's thumb, for l o . the lower lip of the groove 36 which acts as a limit stop. The spring 34 is compressed within the groove 32.

Consequently, the slotted trocar 18 and the catheter tube and protuberance 24 are forced outside of the tubular guide 11 a distance equal to the width of the groove 36.

Once the inward axial force is removed from' the introducer needle handle 16' the spring 34 returns to its original shape and forces the lower edge of the handle 16' against the upper lip of the groove 36. Consequently, the slotted trocar 18 is also wholly drawn into the tubular guide 11. If the trocar 18 has been inserted into a fleshy surface, such as 12 in Figure 6, the barb-shaped protuberance 24 will remain in that surface and will not be drawn back into the tubular guide 11 along with the trocar.

To facilitate handling of the catheter placement unit 30, a finger guide 38 has also been attached to the tubular guide 11. This finger guide may be moulded as a flange on the tubular guide or may be merely affixed to it by a suitable adhesive. Also, a radial slot 37 is provided in the introducer needle handle 16'. The catheter tube 22 can be threaded through the slot 37, thereby avoiding the possibility of pulling the catheter from the flesh into which it has been inserted by inadvertently pinching the tube 22 against the top of the handle 16' while the spring 34 is returning the handle 16' to its original position.

If desired, a substantially radial bore may be substituted for the slot 37.

The catheter placement unit 30 can be used in a The tubular guide 11 is placed against the vaginal mucosa of the patient as shown by 12 in Pig. 5. The doctor then merely pushes the introducer noodle handle 16' into the guide tube, as shown in Pig. 6. Consequently, the slotted trocar 18 is inserted into the patient's vaginal mucosa and carries the catheter and barb -shaped protuberance 24 along with it. The doctor then merely releases the handle 16' and the slotted trocar' 18 springs back into the tubular guide, while the catheter is held in the mucosa by the barb-shaped protuberance 24.

This variation of tho present invention allows the doctor to insert the cathotor into the patient with just one hand. Further, since the introducer needle springs back into tho tubular guide once the handle is released, there is no danger of scratching the mucosa of the patient while the needle is being wit drawn from the vagina .

The catheter placement unit of the present invention can be used in many applications and the description of its use in a continuous paracorvical anesthesia administration system is merely exemplary and not intended to limit the scope of the present invention.

Claims

1. insufficientOCRQuality