CA2030487A1

CA2030487A1 - Method and apparatus for inserting and retaining an epidural catheter

Info

Publication number: CA2030487A1
Application number: CA002030487A
Authority: CA
Inventors: David Goltzer
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-12-08
Filing date: 1990-11-23
Publication date: 1991-06-09
Also published as: GB2238726A; GB9025791D0; US4973305A

Abstract

ABSTRACT OF THE DISCLOSURE
A method of making an epidural insertion of a catheter and means for retention therein whereby a double lumen catheter having an air and medication conduit are provided, and the air conduit has a retention balloon at the distal, epidural end and a pilot indicator balloon at the proximal end. The catheter is inserted through a stylet and the balloon is expanded. The stylet (needle) is withdrawn, the catheter temporarily fastened by external means, the balloons deflated, the needle removed, and the epidural balloon reinflated to hold the catheter in place.

Description

` 203~7 1 Attorney's Docket No. 1312-U-3 2 ll!iETlIOD AND APPAR~T~ E'OR IN~ERTING AND RETAINING AN

3 BPIDURAL CAT~ETER

This invention pertains to means and methods for 6 performing prolonged epidural anaesthesia. Epidural 7 anesthesia is a delicate procedure in which the 8 anaesthetist, after precisely locating the epidural space 9 with a needls without encroaching on the dural structure or penetrating an epidural vein, inserts a catheter for 11 the administration of an analgesic or anaesthetic for 12 retention over a period of hours or days, depending on 13 the patient's condition to be treated.
14 The presently available medical equipment and methods used in such procedures are discussed in 16 "Handbook of Epidural Anaesthesia and Analgesia"
17 published by Grune & Stratton, Inc., Orlando, Florida 1~ 32887.
19 For other applications, "Fogarty" brand arterial embolectomy catheters, made by American Edwards 21 Laboratories, provide a catheter with a balloon tip to be 22 inflated for the purpose of removing emboli and thrombi 23 from arteries. Shinnick patent U.S. No. 3,680,544 24 discloses a spinal syringe and needle, fitted with ~a catheter having an inflatable balloon at its tip. The 26 instrument is designed for insertion through the wall of 27 the heart into the right ventricular cavity. After 28 insertion, the balloon is inflated to prevent 29 displacement of the catheter. When the needle is withdrawn, the catheter remains in place for 31 administering medication to the heart. Taylor patent 32 U.S. No. 3,952,742 discloses a similar device for 33 penetrating the wall of the heart and anchoring the tip 34 of a catheter in place inside the heart by inflating a small balloon. Sheridan/CF (tm) tracheal tube has a 36 pilot balloon whose purpose is to indicate the condition . ~ ~'' ' '' ;:. ` . ~'.'' ' ' ' ' ', ~ ' ' . ` '~' . ~ " , 2 2~30487 1 of a retention balloon inserted in a trachea to retain a ~ tracheal tube.
3 The positioning of the catheter in the epidural 4 space is very important in the epidural anaesthesia process to deliver the anesthetic to the area to be 6 treated, to achieve the purpose of the epidural block.
7 In this connection, excessive movement after positioning 8 of the catheter also produces undesirable effects. Prior 9 art catheter tubes have a high potential for displacement in the epidural space.
11 While performing epidural anaesthesia it is 12 important not to puncture the dura which borders the 13 epidural space on one side. One precautionary measure 14 used to help prevent damage to the dura is to use a lS needle such as the standard Tuohy needle that directs the 16 catheter away from the dural area. Even with the use of 17 an appropriate needle, using a prior art epidural 18 catheter can still readily cause damage to the dura 19 because the flow of anaesthesia can be'directed toward the dura.
21 Prior art catheter tubes have utilized narrow blue 22 or black bands regularly spaced along the tube to 23 indicate incremental lengths of tubing. These bands are 24 often confusin~ and are difficult to read quickly.
Prior art epidural catheters extend from the patient 26 to an external source of medication. They are prone to 27 tangling and are awkward to handle during the insertion 28 of the catheter.
29 Accordingly, an object of this invention is to provide a means for inserting a catheter in the epidura 31 with minimal movement of the catheter after insertion.
32 Another object of this invention is to provide an 33 epidural catheter that is easier to visually position.
34 Still another object of this invention is to provide an epidural catheter that is less likely to cause damage 36 to the dura.

3 203~87 1 Yet still another object of this invention is to 2 provide an epidural catheter that i5 less subject to 3 tangling.
4 Other objects and advantages will become apparent by reference to the following description and drawings.

8 The present invention relates to an apparatus and 9 method for introducing into and maintaining a catheter in a patient's epidural space. I have discovered that a 11 balloon may be used to anchor an epidural catheter 12 securely in place for extended lengths of time without 13 interfering with any necessary natural functions. The 14 catheter of this invention, first being shortened to a manageable first stage length that does nat readily 16 tangle, is introduced into the patient's epidural space 17 by means of a hollow needle, sized to receive the 18 catheter, that is adapted for puncturing the epidural 19 space. A second stage of the catheter is used as an extension of the first stage to provide a connection 21 between the first stage and a remote source of 22 medication. The first stage, sized to fit the bore in 23 the needle, has a broad band of brightly colored indicia 24 which may be red. The indicia is preferably solid `~
(continuous) and marks the length of the needle relative 26 to the epidural end of the catheter.
27 The catheter has an epidural end and an attachment 28 end. Spaced (about 1 to 3 inches, preferably 2 inches) 29 from the epidural end of the catheter and operatively attached to the first stage of the catheter is a 31 retention balloon which communicates with a pilot balloon 32 outside the patient's body. The latter serves to 33 indicate whether or not the retention balloon is ;~
34 inflated.
In accordance with the present invention, the first ~`
36 stage catheter may be from about ten inches to about 20 37 inches, but preferably 15 inches in length. ~ ~
: ' ' "

4 2030~7 l The first color segment preferably is equal to the 2 length of the needle and may define a segment of the 3 catheter immediately behind the retention balloon toward 4 the attachment end. This segment is used to signal that the end of the catheter has reached the top of the needle 6 or some point past the end of the needle, as desired.
7 Further toward the attachment end are narrower 8 conventional marking bands to indicate incremental 9 distances.
The dural arc is sensitive and may be damaged by 11 medication flowing directly at it. If the delivery 12 aperture is positioned away from the dura after 13 insertion, damage is less liXely to occur. Accordingly, 14 the epidural end of the catheter preferably is curved, having a side aperture to direct flow of medication out of the catheter on a path not parallel to the catheter.
17 The positioning of the aperture also provides a means for 18 directional flow.
19 The apparatus described above may be used in conjunction with the following method of performing an 21 epidural block The first step is to insert the 22 introducing needle into the epidural space. The catheter 23 is then inserted through the needle into the epidural 24 space. The correct placement of the catheter in the needle in the epidural space is determined with reference 26 to colored indicia carried on the catheter. The catheter 27 is fed into the epidural space to the appropriate 28 location by visualizing colored measurement indicia on 29 the catheter, conveniently, a brightly colored broad band which is no longer visible when the catheter has reached 31 the tip of the needle. The catheter may be further fed 32 into the bore of the needle and the additional bands may 33 be used to indicate how far past the needle the tip of 34 the catheter has progressed.
The catheter has an inflatable epidural balloon near 36 its epidurally inserted end and a pilot balloon outside 37 the patient's body which is in fluid communication with 38 the epidural balloon. The latter is inflated to retain .: ~ : , : , , , , , - .

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5 203~8~

1 the catheter in place, and the pilot balloon is visually 2 inspected to verify that the epidural balloon is 3 inflated.
4 The needle is then withdrawn from the epidural space, after which the catheter may be temporarily 6 fastened into place. The pilot balloon may then be 7 deflated to remove the needle from the catheter.

8 Finally, the external end of the catheter is attached to 9 a source of medication.

12 In order that the invention may be better 13 understood, a description of the invention is provided 14 herein with reference to the general concepts and an illustrative embodiment thereof, wherein:
16 FIG. 1 is a perspective view of a presently 17 preferred embodiment o~ the catheter to be used for 18 performing epidural anaesthesia;
19 FIG. 1~ is a portion lA of Fig. 1, greatly enlarged, and partially sectioned;
21 FIG. lB is a cross section of Fig. 1 taken along the 22 sight of l~-lB;
23 FIG. 2 is an enlarged view of the retention balloon 24 at the tip of the catheter shown in Fig. l;
FIG. 3 is a diagrammatic view in cross section 26 between a portion of the spinal column of a patient, 27 showing in accordance with this invention the catheter 28 inserted with the needle into the epidural space;
29 FIG. 4 is a diagrammatic view of Fig. 5 showing the catheter inserted with the use of a needle into the 31 epidural space with the retention balloon inflated;
32 FIG. 5 is a diagrammatic view of the spinous 33 processes showing the catheter temporarily fastened in 34 place and the needle withdrawn;
FIG. 6 is a diagrammatic view of the spinous 36 processes showing the catheter with the retention balloon 37 and pilot balloon inflated and the external end of the 38 catheter attached to a source of medication;

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6 2~3~487 1 FIG. 7 is an alternative embodiment of that portion 2 of Fig. 1 corresponding to Fig. lA:
3 FIG. 8 is a cross section, greatly enlarged, of Fig.
4 7 taken along the line 8-8; and FIG. 9 is an enlarged view of the alternative 6 embodiment of the retention balloon at the tip of the 7 catheter.

The description of the preferred embodiment set 11 forth hereafter concerns a double-lumen epidural catheter 12 with the tubes being concentric, one within the other.
13 However, multi lumen epidural catheters of other 14 architectures may be employed.
Referring now to FIGS. 1-2, catheter 10 having has 16 an inner medication tube 14 with a distal tip 16 and 17 proximal portion 18 forming a conduit 26 for an 18 anaesthetic solution and an outer air tube 20 terminating l9 in balloon 12.
At the proximal or attachment end of the catheter 21 10, the inner 14 and outer 20 tubes are split. At the 22 proximal end 24 of the outer tube 20 is a pilot balloon 23 30. The tube at the proximal end 24 of the pilot balloon 24 30 is flanged and adapted for the insertion of a specially made syringe. Via the syringe, air enters into 26 the proximal end 24 of the outer tube 20 into the pilot 27 balloon 30, through the conduit 28 of the outer tube 20 28 and into the retention balloon 12 at the distal end thus 29 inflating both balloons. The pilot balloon 30 will remain inflated as long as the retention balloon 12 is 31 inflated providing an indicator for the condition of the 32 retention balloon 12.
33 The inner tube 14 at the proximal end 18 is flanged, 34 allowing a catheter extension to be attached. The extension makes the catheter long enough to reach the 36 source of medication. By providing a means for extending 37 the catheter, the catheter that is inserted can be made a 38 manageable length that is not readily entangled.

..... , . , , ~ -: - . . .- . . . .
.... . . - . ~ . .....

7 21~3~

1 At the distal tip 16 of the inner tube 14, there is 2 an aperture 32 through which the medication flows. The 3 aperture 32 is not located at the end of the tube but 4 instead on the side to provide a means for directional flow. If the delivery aperture is positioned away from 6 the dura after insertion, damage is less likely to occur 7 to the dura.
8 A broad red band 34 that is of the same length as 9 the length of the needle is appropriately located on the tube. The length o~ the ~and 34 is used to signal the 11 position of the catheter and when the band disappears the 12 end of the catheter has reached the tip of the needle.
13 Further up the catheter are additional bands 36 - 38 that 14 can be used to indicate how far past the needle the tip of the catheter has progressed.
16 FIGS. 3-6 are a series of views depicting the 17 catheter in use in accordance with the present invéntion.
18 In FIG 3, an epidural needle 40 is introduced into the 19 epidural space slowly and gradu~lly. The needle 40 used to locate the catheter 10 in the epidural space 42 passes 21 successively through the skin 44, subcutaneous tissue 46, 22 interspinous ligament 48 and ligamentum flavum 50 to 23 finally reach the epidùral space 42. After epidural 24 placement of the needle 40 has been assured, the epidural catheter 10 is then introduced into the epidural space 42 26 through the needle 40. The epidural catheter 10 is 27 inserted a desired distance into the epidural space 42.
28 The necessary distance is known to have been achieved by 29 observing the location of the broad red band 34 and subsidiary bands 36 and 38 on the catheter 10.
31 In FIG. 4 air is injected into the proximal end 24 32 of the outer tube 20 causing the retention balloon 12 to 33 inflate. The inflated retention balloon 12 allows the 34 needle 40 to be withdrawn without fear that the catheter will be dislodged.
36 After the needle is withdrawn from the patient, the 37 catheter is temporarily attached in place with, for 38 example, adhesive tape 52 as shown in FIG. 5. ~he pilot : : : , .. ~ , . ; ...

8 2030 ~

1 balloon 30 is then deflated to allow the needle 40 to be 2 removed from the catheter 10.
3 After the needle 40 has been removed, the retention balloon 12 and the pilot balloon 30 are again inflated as shown in FIG 6. A clamp 54 engages and seals the 6 proximal end 24 of the outside tube to prevent the escape 7 of air from the balloons 12 and 30. The temporary 8 adhesive tape 52 is now removed. The catheter extension 9 56 is atta~hed to the proximal end 18 of the inner tube 14 to permit the injection of medication into the 11 epidural space 42. In this embodiment it is recommended 12 that a catheter having a non-kinking lumen be used. An 13 example of a non-kinking catheter can be obtained from 14 Arrow International, Inc., Reading, Pennsylvania 19610.
An alternative embodiment is shown in Fig. 7 wherein 16 the pilot balloon 30 is detachable from the air tube 20a 17 which can be placed inside the medication tube 14a. The 18 tube 20a has a slightly flared mouth 20b to receive a 19 force fit of the end 20c of the pilot balloon extension tube 20d. Thus, the pilot balloon 30 can be removed to 21 permit the facile removal of the needle 40 from the `
22 catheter.
23 For convenience a list of the various elements and 24 their identifying members are provided below:

10 catheter 26 12 retention balloon 27 14 inner medication tube 28 14a medication tube 29 16 distal tip 18 proximal end 31 20 outer air tube 32 20a air tube 33 2Ob flared mouth 34 20c end 20d balloon extension tube ~ -36 24 proximal end 37 26 conduit 38 28 conduit 39 30 pilot balloon 32 aperture 41 34 band 42 36 band 43 38 band 44 40 epidural needle 9 2~30~

1 42 epidural space 2 44 skin 3 46 subcutaneous tissue 4 48 interspinous ligament 50 ligamentum flavum 6 52 adhesive tape 7 54 clamp B 56 catheter extension 9 While representative presently preferred embodiments of the invention are disclosed above, the invention :

11 encompasses various equivalent structures and functions 12 as distinctly claimed and pointed out in claims appended 13 hereto.

14 What is claimed is:

'

Claims

1. Apparatus for introducing into and maintaining a catheter in a patient's epidural space comprising:
a. a hollow needle having means adapted for the puncture of an epidural space and a bore sized to permit the introduction of a catheter through said bore into the patient's epidural space;
b. a two-stage catheter having (1) a shortened first stage sized to fit said bore;
(2) an epidural end and an attachment end; and (3) brightly colored indicia, marking the length of said needle relative to the epidural end of said catheter;
c. a retention balloon operatively attached at said epidural end, a pilot balloon disposed to operate outside the patient's body and having fluid communication with said retention balloon; and d. means for attaching said catheter to the source of medication.

2. The apparatus of claim 1 wherein the length of said first stage catheter is from about ten inches to about twenty inches in length.

3. The apparatus of claim 2 wherein the length of said first stage catheter is about fifteen inches in length.

4. The apparatus of claim 1 wherein the retention balloon is spaced from the epidural end of said catheter about 1 to 3 inches.

5. The apparatus of claim 4 wherein the retention balloon is spaced from the epidural end of said catheter about 2 inches.

6. The apparatus of claim 1 wherein said first color segment is equal to the length of said needle and defines a segment of the catheter immediately behind said retention balloon toward the attachment end.

7. The apparatus of claim 1 wherein the epidural end of said catheter is curved having an aperture located such that flow of medication out of said catheter is directed in a path which is not parallel to the catheter.

8. The apparatus of claim 1 further comprising extension means to connect the catheter to a remote source of medication.

9. A method of performing an epidural block comprising the steps of:
a. inserting an introducing needle into the epidural space;
b. inserting through the needle into the epidural space a catheter having an inflatable epidural balloon near its epidurally inserted end and a pilot balloon in fluid communication with the epidural balloon;
c. inflating the epidural balloon to retain the catheter in place and verifying inflation by visually inspecting the pilot balloon;
d. withdrawing the needle; and e. attaching the external end of the catheter to a source of medication.

10. The method of claim 9 further comprising the step of determining the correct placement of the catheter in the needle in the epidural space with reference to colored indicia carried on the catheter.

11. The method of claim 9 further comprising the step of feeding the catheter into the epidural space by visualizing colored measurement indicia on the catheter.

12 12. A method of performing an epidural block comprising the steps of:
a. inserting an introducing needle into the epidural space;
b. inserting through the needle into the epidural space a catheter having an inflatable epidural balloon near its epidurally inserted end and a pilot balloon in fluid communication with the epidural balloon;
c. temporarily fastening the catheter in place and deflating the said balloons to permit withdrawal of said needle;
d. withdrawing said needle from said catheter; and e. reinflating said balloons.