Catheter apparatus with means for subcutaneous delivery of anesthetic agent or other fluid medicament

A novel catheter apparatus for use in delivering an anesthetic agent or other fluid medicament to the portion of subcutaneous tissue through which a catheter device has been inserted into a patient, thereby allowing the catheter device to be retracted without causing pain or discomfort to the patient. The catheter device has an indwelling cannula adapted for insertion through subcutaneous tissue into a patient's body. A cylindrical sheath is placed on the cannula so as to be positioned within the subcutaneous tissue once the cannula has been inserted into the body. The cylindrical sheath has formed therein a lumen into which the anesthetic agent or other fluid medicament can be delivered via a hub that is disposed on the catheter apparatus. The cylindrical sheath has formed therein a plurality of one-way slit valves. The one-way slit valves permit the anesthetic agent or fluid medicament to be delivered to the surrounding subcutaneous tissue, and also prevent any bodily fluids from entering the lumen. In one embodiment the cylindrical sheath is permanently mounted to the cannula. In another embodiment the cylindrical sheath is detachably mountable to the cannula. In yet another embodiment, the lumen is formed within the outer wall of the cannula and the one-way slits are formed through the outer wall.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a catheter apparatus with a means for 
subcutaneous delivery of anesthetic agents or other fluid medicaments, and 
more particularly to catheter apparatus having subcutaneous infusion ports 
that provide for the administration of a local anesthesia or other 
medicaments to an area of subcutaneous tissue through which a cannula has 
been inserted. 
2. The Present State of the Art 
Catheter devices are widely used for a variety of medical applications. 
Generally, a catheter is a hollow, tubular cannula that is capable of 
being inserted into canals, vessels, passageways, or other body cavities 
so as to permit injection or withdrawal of fluids, or to keep a passage 
open. Other catheter devices are used for controlling, directing and 
placing medical devices, such as intubation tubes or dilation catheters, 
into a body cavity, such as the trachea, a blood vessel, or the heart 
These types of insertion catheters are commonly referred to as intubators, 
insertion sheaths, and/or dilators. Given that catheters are used for such 
a wide variety of applications, catheters are implemented in a variety of 
designs, shapes and sizes. However, when used, almost all catheters Share 
the universal characteristic of having to be passed through the skin and 
subcutaneous tissue of the patient so as to be inserted into the proper 
body cavity. 
Depending on the medical procedure, the catheter is very often left in the 
body cavity over a relatively long period of time. As such, the skin and 
subcutaneous tissue through which the catheter device is inserted often 
becomes very swollen and tender, and thus extremely sensitive. 
Consequently, when the catheter is eventually retracted from the patient, 
the patient will often experience great discomfort. This discomfort may 
agitate the patient and thereby hinder the ability of medical personnel to 
effectively retract the catheter and/or treat the patient. 
For example, in a percutaneous transluminal coronary angioplasty (PTCA) 
procedure, a patient is administered a local anesthesia and an 
intravascular sheath introducer (a type of catheter device) is inserted 
through the patient's skin in the groin area and into the femoral artery. 
In so doing, the sheath introducer necessarily passes through the area of 
subcutaneous tissue that lies between the skin and the femoral artery. 
Once inserted, the sheath introducer catheter provides a means for 
introducing the dilation catheter for performing the PTCA procedure. 
Following the PTCA procedure, the sheath introducer is usually left within 
the femoral artery for a period ranging between four to twenty-four hours. 
Typically, the sheath is left in place because blood thinning drugs, such 
as Heparin, are administered to the patient. The effects of such drugs 
must wear off before the sheath can be removed in order to avoid 
hemorrhaging problems. Similarly, the device may be left in the patient as 
a precaution, in case quick access to the femoral artery is needed due to 
subsequent complications, such as an abrupt closure of the artery. In any 
event, by the time the sheath is retracted, the patient's skin and 
subcutaneous tissue through which the catheter is inserted is typically 
very swollen, bruised and tender. Also, by this time, the numbing effects 
of the earlier administered local anesthesia have completely worn off. 
Consequently, as the sheath is retracted from the femoral artery, the 
subcutaneous tissue and the overlying skin, the patient can experience 
considerable pain. 
Pain experienced during sheath removal is known to occasionally cause 
vasovagal syncope type reactions, which can potentially result in a 
variety of undesirable patient responses--including a drop in blood 
pressure and heart rate. This can be hazardous when it occurs so soon 
after the PTCA procedure, and may thus require treatment with intravenous 
Atropine, or other drugs. Pain may also cause the patient to become 
agitated, which makes it difficult for medical personnel to properly 
administer arterial compression. This can lead to a hematoma formation 
within the subcutaneous tissue adjacent to the catheter. 
Although medical personnel can administer a local anesthesia to the area, 
this must be done with a hypodermic needle, which usually causes as much 
discomfort or pain as the actual retraction of the catheter device. Thus, 
there is not a medical device available which adequately relieves a 
patient's discomfort during catheter retraction, and there is a need to be 
able to administer a local anesthesia to the subcutaneous tissue 
surrounding a catheter device prior to the retraction of the device, in a 
relatively painless and easy manner. 
BRIEF SUMMARY AND OBJECTS OF THE INVENTION 
The apparatus of the present invention has been developed in response to 
the present state of the art, and in particular, in response to the 
problems involved with the pain and discomfort that is experienced by a 
patient when a catheter device is removed. Thus, it is an overall object 
of the present invention to provide an apparatus which provides for the 
ability to painlessly administer local anesthesia or other medicaments to 
an area of subcutaneous tissue through which a catheter device has been 
inserted. 
A further object of the present invention is to provide an apparatus that 
permits subcutaneous delivery of such medicaments but which also prevents 
bodily fluids from entering the apparatus while it is inserted and remains 
within the patient's body. 
Yet another important object of the present invention is to provide an 
anesthetizing catheter sheath apparatus that can be manufactured either as 
an integral part of a catheter device, or as an apparatus that can be 
detachably mounted to a catheter device. 
Additional objects and advantages of the invention will be set forth in the 
description which follows, and in part will be obvious from the 
description, or may be learned by the practice of the invention. The 
objects and advantages of the invention may be realized and obtained by 
means of the instruments and combinations particularly pointed out in the 
appended claims. 
Briefly summarized, the foregoing and other objects are achieved with a 
catheter apparatus that is inserted into a patient's body through 
subcutaneous tissue. In one presently preferred embodiment, a sheath fits 
over the catheter and is designed for insertion together with the catheter 
through the subcutaneous tissue. Once the catheter device is inserted into 
the patient's body, the outer surface of the catheter device necessarily 
passes through the patient's skin and a portion of underlying, 
subcutaneous tissue. The sheath which is disposed on the outer surface of 
the catheter device is also thus inserted through the subcutaneous tissue. 
Prior to retracting the catheter device, medical personnel can administer 
an anesthetic agent by infusing it into the surrounding subcutaneous 
tissue from the anesthetizing sheath. In this way, the subcutaneous tissue 
will be numbed, and the patient will experience no pain while the catheter 
device is retracted. In addition to anesthetic agents, the sheath can also 
be used to deliver a wide variety of other types of fluid medicaments to 
the subcutaneous tissue. For instance, the sheath may be used to deliver 
topical antibacterial agents to the tissue. 
In one presently preferred embodiment of the present invention, the 
anesthetizing sheath apparatus can be permanently mounted to the catheter 
device, and is thus manufactured as an integral part of the catheter 
device. 
In another presently preferred embodiment of the present invention, the 
anesthetizing sheath can be detachably mountable to the outer surface of 
the catheter device. In this manner, the anesthetizing sheath can be 
designed for use with any of a wide variety of existing catheter devices 
already on the market, thereby increasing its versatility. 
In a still further embodiment of the invention, rather than using a sheath, 
the outer wall of the catheter device is provided with a secondary lumen, 
into which the anesthetic agent is injected and from which the anesthetic 
agent is infused into surrounding subcutaneous tissue.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Reference is next made to the drawings, wherein like parts are designated 
with like numerals throughout. Referring first to FIG. 1, one presently 
preferred embodiment of the invention is illustrated. FIG. 1 represents a 
perspective view of the catheter apparatus of the present invention, 
designated generally at 10. Catheter apparatus 10 includes a catheter 
means, as for example a catheter device designated generally at 12, for 
insertion through subcutaneous tissue. As used herein, the term catheter 
device is intended to broadly cover the general category of cannula-type 
devices referred to as catheters. Thus the term catheter device is 
intended to refer to any hollow, tubular cannula-type device that is 
capable of being inserted into canals, vessels, passageways, or other body 
cavities so as to permit injection or withdrawal of fluids, or to keep a 
passage open. Further, the term is intended to include insertion devices 
which are used for controlling, directing and placing medical devices, 
such as intubation tubes or dilation catheters, into a body cavity, such 
as the trachea, a blood vessel, or the heart, and which are commonly 
referred to as intubators, insertion sheaths, and/or dilators. 
For purposes of example, the catheter device 12 illustrated in FIG. 1 is an 
insertion sheath comprised of an indwelling cannula 14 which is adapted 
for insertion through subcutaneous tissue and into a patient's body. As is 
better shown in FIG. 2, the cannula 14 is inserted into a patient's body 
(typically via a guide wire while the patient is numbed with a local 
anesthetic) so as to have a distal end 17 disposed within a body cavity, 
such as a blood vessel 16. As is shown, the cannula 14 necessarily passes 
through the patient's skin layer 18 and the area of subcutaneous tissue 20 
that lies between the skin layer 18 and the body cavity, such as the blood 
vessel 16. Thus, once the cannula 14 is properly positioned, a portion 22 
of the cannula 14 remains disposed within the area of subcutaneous tissue 
20. 
Once in place, the insertion sheath cannula 14 is used for controlling and 
directing the placement of another medical device, as for example a 
dilation catheter 24 for use in a PTCA procedure. The dilation catheter 24 
is inserted into the hollow cannula 14 via the proximal hub end 26 of the 
catheter device 12, and the tubing 23 and connector 25 attached thereto. 
The proximal hub end 26 remains positioned outside of the body. Upon 
completion of the PTCA (or related) procedure, the dilation catheter 24 is 
removed from the cannula 14 through the proximal hub end 26. Typically, 
the distal end portion 17 of the cannula 14 then remains positioned within 
the patient, sometimes for as long as twenty-four hours. At the end of 
this time period (by which time all numbing effects of the local 
anesthesia have worn off) the patient's skin 18 and subcutaneous tissue 20 
are swollen and very sensitive, and retraction of the cannula 14 can be 
extremely painful. 
Referring again to FIG. 1, the catheter apparatus 10 of the present 
invention further comprises a sheath means, as for example a hollow 
cylindrical sleeve generally designated at 28, for placement onto at least 
a portion of the cannula 14 at a point intermediate of the distal end 17 
and the proximal hub end 26. As is better shown in FIG. 2, the cylindrical 
sleeve 28 is positioned on the cannula 14 so as to be disposed on the 
portion 22 of cannula 14 that is surrounded by subcutaneous tissue 20 when 
the cannula 14 is indwelling within the patient's body. 
As is shown in the preferred embodiment of FIGS. 1 and 2, the cylindrical 
sleeve 28 has a distal end 30 and a proximal end 32. The cross-sectional 
view of FIG. 3 illustrates how hollow cylindrical sleeve 28 has an inner 
diameter which is greater than the outer diameter of cannula 14, and how 
cylindrical sleeve 28 is positioned on cannula 14 so as to be concentric 
with the cannula 14. Preferably, distal end 30 of cylindrical sleeve 28 is 
tapered where it terminates on the outer surface of cannula 14 so that the 
cylindrical sleeve 28 can be inserted with little or no trauma through the 
outer skin layer 18 and subcutaneous tissue 20. This tapered distal end 30 
is best seen in FIG. 2. 
The sheath means is further comprised of a means for sealing the sheath 
means in a fluid tight manner around the cannula 14 so as to prevent 
fluids, such as blood from the body, from escaping between the cannula 14 
and the sheath means. In the embodiment of FIGS. 1 and 2, for example, 
this sealing function is accomplished by permanently affixing the 
cylindrical sleeve 28 over the outer surface 22 of the cannula 14. Thus, 
in this embodiment, the distal end 30 of the cylindrical sleeve 28 is 
fused, or otherwise suitably affixed, to the cannula 14. By so doing, 
fluids are prevented from entering the space or interior lumen 38 between 
the outer surface of the cannula 14 and the cylindrical sleeve 28. 
The sheath means, as for example cylindrical sleeve 28, is further 
comprised of a means for delivering fluid medicament, such as an 
anesthetic agent (not shown), to essentially only that portion of 
subcutaneous tissue 20 that surrounds the sheath means. Delivery of fluid 
medicament is accomplished, for example, by way of the interior lumen 38 
running from the distal end 30 to the proximal end 32 of the cylindrical 
sleeve 28. Delivery of fluid medicament is also aided by a hub means for 
delivering the fluid medicament to the interior lumen 38, and a plurality 
of valve means for communicating the fluid medicament from the interior 
lumen 38 to the subcutaneous tissue surrounding the sheath means. 
By way of example, FIG. 2 illustrates cylindrical sleeve 28 as being 
comprised of a single cylindrical wall 36. In this particular embodiment, 
the interior lumen 38 is formed between the cylindrical wall 36 and the 
outer surface of the cannula 14. Interior lumen 38 is also shown in the 
cross-sectional view of FIG. 3. 
By way of further example, FIGS. 1 and 2 illustrate how the hub means can 
be comprised of a hub 40 that is joined in a fluid tight manner to the 
proximal end 32 of the cylindrical sleeve 28, and to the proximal hub end 
27 of the cannula 14. Hub 40 further comprises, for example, a first 
passageway means, such as a first hub lumen 42, for communicating the 
fluid medicament to the interior lumen 38. In addition, hub 40 comprises a 
second passageway means, such as second lumen 44, for providing fluid 
communication to the cannula 14 via a cannula access hole 46. FIG. 1 
illustrates how the first and second hub lumens 42, 44 are preferably 
coupled to multi-lumen tube 41. Multi-lumen tube 41 is branched such that 
first hub lumen 42 is coupled to an infusion port 43, and second hub lumen 
is coupled to an I.V. valve assembly 45. In this way, a medical technician 
can administer fluid medicament with a syringe to the interior lumen 38 
using infusion port 43. 
By way of further example, FIG. 1 illustrates how the plurality of valve 
means are preferably comprised of a plurality of one way valve means 
spaced along the cylindrical sleeve 28. The one-way valve means not only 
allow the fluid medicament to be communicated from the interior lumen 38 
to the subcutaneous tissue 20, but also act so as to prevent bodily fluids 
from entering the interior lumen 38. The one way valve function is 
provided by a plurality of one way slits 48 placed uniformly about the 
cylindrical sleeve 28. Because the width of the subcutaneous tissue 20 
will vary from patient to patient, it is possible that the distal end 30 
of the cylindrical sleeve 28, along with some of the slits 48, could be 
disposed within the blood vessel 16. In this situation, the one way slits 
48 positioned within the portion of subcutaneous tissue 20 will properly 
communicate the anesthetic agent to the tissue 20, but any of the one way 
slits 48 that are located within the blood vessel 16 will prevent bodily 
fluids, such as blood, from entering the interior lumen 38. 
As is further shown in FIG. 1, each slit 48 is preferably made 
longitudinally along the axis of the cylindrical sleeve 28. Slits 48 are 
uniformly located about the periphery of the cylindrical sleeve 28 so as 
to insure that the anesthetizing agent is evenly and uniformly delivered 
to the surrounding subcutaneous tissue 20. Further, the longitudinal 
length of each slit 48 changes depending on its location on the 
cylindrical sleeve 28. Preferably the slits 28 become progressively 
shorter as they near the proximal end 32 of the cylindrical sleeve 28. 
This variation in slit length is intended to help assure that fluid 
medicament is uniformly delivered from the proximal end 32 to the distal 
end 30 of sleeve 38. This may be especially important if one or more 
proximately located slits 48 are located outside of the patient's body 
during delivery of the fluid medicament. 
As is shown in FIGS. 3-5, each one way slit 48 extends completely through 
the cylindrical wall 36 of the cylindrical sleeve 28 so as to provide 
fluid communication with interior lumen 38. It is shown best in FIGS. 4 
and 5 wherein each slit 48 is defined by opposed, aligned, normally 
abutting, parallel edges 50. FIG. 4 illustrates how a square portion 51 of 
the abutting edges 50 are normally engaged in a sealing relationship, and 
wherein the slit 48 is thereby in a closed position. The abutting edges 50 
are further formed with rounded internal edge portions 52 that do not 
abut, but are spaced apart. In this closed position (shown in FIG. 4), the 
slit 48 will prevent any bodily fluids from entering the interior lumen 
38. 
Wall edges 50 are also capable of flexing outwardly from their closed 
position, responsive to a pressure generated within the interior lumen 38. 
In so doing, an orifice 54 is created, through which fluid such as the 
anesthetic agent, can flow. This open position is illustrated in FIG. 5. 
Thus, by applying a predetermined positive pressure to interior lumen 38, 
a fluid medicant such as an anesthetic agent is infused into the area of 
subcutaneous tissue 20 in which the cylindrical sleeve 28 is disposed, as 
shown in FIG. 2. 
Slits 48 normally remain closed and wall edges 50 remain in an abutting 
position (FIG. 4). This requires that the cylindrical sleeve 28 have 
sufficient memory to return the slits 48 to the closed position after 
infusion of anesthetic agent is terminated. The cylindrical sleeve 28 may 
be constructed from a variety of materials with the required elasticity. 
Preferably, the cylindrical sleeve 28 is rigid enough to be easily 
inserted into the area of subcutaneous tissue 20 in conjunction with the 
cannula 14. At the same time, the cylindrical sleeve 28 should be flexible 
enough so as to conform to the movements of the patient, and such that the 
slits 48 exhibit the unidirectional fluid flow properties discussed above 
in connection with FIGS. 4 and 5. 
In the preferred embodiment, cylindrical sleeve 28 is made from a 
polyurethane material. Also, teflon or polyethylene materials may be 
suitable. The sleeve material can have a Shore A durometer in the range 
from about 80 to about 100, and preferably will be in the range from about 
55 to about 70. 
It will be appreciated that the valve means may be comprised of a variety 
of equivalent structures. For instance, valve means could be comprised of 
a plurality of holes formed through the cylindrical wall 36 of the 
cylindrical sleeve 28. Further, this structure could provide a one way 
fluid flow function if the holes are made sufficiently large with respect 
to the width of interior lumen 38. In such an embodiment, the pressures 
exerted by bodily fluids, such as interstitial blood pressure, would 
compress the interior lumen 38 and thereby prevent back-flow of bodily 
fluids back into the interior lumen 38 through the holes. 
With continued reference to FIGS. 1 and 2, formed on the hub 40 near 
proximal end 32 of the cylindrical sleeve 28 is a suture attachment ring 
47. Once the cylindrical sleeve 28, in conjunction with the insertion 
sheath cannula 14, has been positioned within the portion of subcutaneous 
tissue 20, the physician can suture, or otherwise attach, the cylindrical 
sleeve 28 to the patient via the suture attachment ring 47. In this 
manner, the cylindrical sleeve 28 will stay correctly positioned within 
the portion of subcutaneous tissue 20 during subsequent medical 
procedures, such as a PTCA. This insures that medical personnel can 
administer a fluid medicament, such as an anesthetic agent, to the 
subcutaneous tissue 20 without first having to reposition the cylindrical 
sleeve 28. 
Another embodiment of the catheter apparatus of the present invention is 
illustrated in FIGS. 6 through 8, and is designated generally at 10b. 
Catheter apparatus 10b includes a catheter means, as for example a 
catheter device designated generally at 12 which is essentially the same 
as the catheter device discussed in conjunction with FIGS. 1 through 3. 
That discussion will not be repeated here. 
The indwelling catheter apparatus 10b also comprises a sheath means, as for 
example a hollow cylindrical sleeve 56, for placement onto at least a 
portion of the cannula 14 at a point intermediate of the distal end 17 and 
the proximal hub end 26 of the cannula 14. However, unlike the embodiment 
shown in FIGS. 1 through 3, the sheath means of FIGS. 6 through 8 can be 
selectively attached and detached to the cannula 22, as discussed in 
further detail below. 
As is shown in FIGS. 6 and 7, cylindrical sleeve 56 has a distal end 58 and 
a proximal end 60. Hollow cylindrical sleeve 56 further has an inner 
diameter which is greater than the outer diameter of cannula 14. This 
relationship is also shown in the cross-sectional view of FIG. 8. Also 
shown in FIG. 8 is how cylindrical sleeve 56 is positioned, in a tight 
fitting manner, on cannula 14 so as to be concentric with the cannula 14. 
Preferably, distal end 58 of cylindrical sleeve 56 is tapered with respect 
to the outer surface 22 of cannula 14, so that the cylindrical sleeve 56 
can be inserted with little or no trauma through the portion of 
subcutaneous tissue 20 when it is mounted to the cannula 14. 
The cylindrical sleeve 56 further comprises a means for delivering fluid 
medicament, such as an anesthetic agent, to the subcutaneous tissue 20 
surrounding the sleeve 56. The fluid medicament delivering means 
comprises, for example, a means for defining an interior lumen running 
from the distal end 58 to the proximal end 60 of the sleeve 56, a hub 
means through which the fluid medicament is delivered to the interior 
lumen, and a plurality of one way valve means for communicating the fluid 
medicament from the interior lumen to the subcutaneous tissue 20 
surrounding the sleeve 56 and for preventing fluids from entering the 
interior lumen. 
By way of example, and referring now to FIG. 8, cylindrical sleeve 56 is 
illustrated as being comprised of a cylindrical outer wall 62 that is 
formed over a concentric cylindrical inner wall 64 in a spaced apart 
relationship. Thus, in this embodiment, an interior lumen 66 is provided 
by the space between the outer wall 62 and the inner wall 64. 
By way of further example and with continued reference to FIGS. 6 and 7 in 
combination, the hub means is comprised of a first hub 72. In the 
preferred embodiment, first hub 72 is joined in a fluid tight manner to 
the proximal end 60 of the cylindrical sleeve 56. First hub 72 further 
comprises, for example, a first passageway means, such as a first hub 
lumen (not shown), for communicating the anesthetic agent to the interior 
lumen 66. As is shown in FIG. 6 and 7, the first hub 72 can be attached, 
for example, to an external tube 74 through which the anesthetic agent can 
be introduced to the internal lumen 66, as for example by a syringe (not 
shown), via an infusion port 76. 
FIGS. 6 through 8 further illustrate the preferred embodiment of the 
plurality of one way valve means spaced along the cylindrical sleeve 56. 
As is shown, each valve means is comprised of a one way slit 82 that is 
formed through outer wall 62 of cylindrical sleeve 56. These slits 82 are 
preferably substantially identical to the one way slits 48 described above 
in connection with FIGS. 1 through 3, and that discussion will not be 
repeated here. 
As is further shown in FIGS. 6 through 8, in this particular embodiment 
sleeve 56 is further comprised of a means for selectively attaching and 
detaching the sleeve 56 from the cannula 14. For example, the means for 
selectively attaching and detaching is illustrated as being comprised of a 
continuous slit 68 that extends longitudinally along the entire length of 
the cylindrical sleeve 56. Slit 68 has a width such that the cylindrical 
sleeve 56 can be detachably mounted to the cannula 14 through the slit 68. 
The cylindrical sleeve 56 in such a mounted position is illustrated in 
FIGS. 7 and 8. 
Referring now to FIG. 8, when cylindrical sleeve 56 is mounted to cannula 
14, the cylindrical inner wall 64 is in continuous contact with the outer 
surface of cannula 14. This tight fitting position is maintained by the 
resilient properties that are preferably exhibited by cylindrical sleeve 
56. As is further shown, the edges 69 and 69' where the outer wall 62 
meets inner wall 64 are tapered with respect to the outer surface of the 
cannula 14. This permits the cylindrical sleeve 56 to be inserted with 
less trauma into the subcutaneous tissue, and it further forms a tight 
seal between the cylindrical sleeve 56 and cannula 14 so as to prevent 
bodily fluids from leaking between sleeve 56 and cannula 14. 
The sheath means of this embodiment is also comprised of a means for 
sealing the sheath means in a fluid tight manner around the cannula 14 so 
as to prevent fluids, such as blood from the body, from escaping between 
the cannula 14 and the sleeve 56. For example, as is shown in both FIGS. 6 
and 7, this sealing is accomplished by placing an O-ring 70 between the 
cylindrical sleeve 56 and the outer surface of the cannula 14. Thus, when 
the cylindrical sleeve 56 is mounted to the cannula 14, O-ring 70 forms a 
fluid-tight seal, and thereby prevents any bodily fluids from leaking 
between sleeve 56 and cannula 14. Cylindrical sleeve 56 also has formed 
thereon a suture attachment ring 47, similar to the ring 47 discussed 
above in connection with FIGS. 1 through 3. 
In the embodiment of FIGS. 6 and 7, the indwelling catheter apparatus 
further includes a second hub means, as for example hub 78, for providing 
fluid communication to the cannula 14. Hub 78 is joined in a fluid tight 
manner to the proximal end of cannula 14. As is also shown, hub 78 can be 
connected to external tube 80, through which fluids may be infused to 
cannula 14. A dilation catheter may be introduced into cannula 14 through 
tubing 23 and connector 25. 
Yet another embodiment of the indwelling catheter apparatus of present 
invention is illustrated in FIGS. 9 through 11, and is designated 
generally at 10c. Indwelling catheter apparatus 10c also includes a 
catheter means, as for example a catheter device, which is essentially the 
same as the catheter device discussed in conjunction with FIGS. 1 through 
3. 
The indwelling catheter apparatus 10c also comprises a sheath means, as for 
example a hollow cylindrical sleeve 86, for placement onto at least a 
portion of the cannula 14 at a point intermediate of the distal end 17 and 
the proximal hub end 26 of the cannula 14. As with the embodiment shown in 
FIGS. 6 through 8, the sheath means of FIGS. 9 through 11 can be 
selectively attached and detached to the cannula 14, as will be discussed 
in further detail below. 
As is shown in FIGS. 9 and 10, cylindrical sleeve 86 has a distal 88 and a 
proximal end 90. Hollow cylindrical sleeve 86 further has an inner 
diameter which is greater than the outer diameter of cannula 14. This 
relationship is also shown in the cross-sectional view of FIG. 11. Also 
shown in FIG. 11 is cylindrical sleeve 86 positioned in a tight fitting 
manner on cannula 14 so as to be concentric with the cannula 14. 
Preferably, distal end 88 of cylindrical sleeve 86 is tapered with respect 
to the outer surface of cannula 14, so that the cylindrical sleeve 86 can 
be inserted with little or no trauma through the portion of subcutaneous 
tissue 20 when it is mounted to the cannula 14. 
The cylindrical sleeve 86 further comprises a means for delivering fluid 
medicament, such as an anesthetic agent (not shown), to the subcutaneous 
tissue 20 surrounding the sleeve 86. The fluid medicament delivering means 
comprises, for example, a means for defining an interior lumen running 
from the distal end 88 to the proximal end 90 of the sleeve 86, a hub 
means through which the fluid medicament is delivered to the interior 
lumen, and a plurality of one way valve means for communicating the fluid 
medicament from the interior lumen to the subcutaneous tissue surrounding 
the sheath means and for preventing fluids from entering the interior 
lumen. 
By way of example, and referring now to FIG. 11, cylindrical sleeve 86 is 
illustrated as being comprised of a cylindrical outer wall 92 that is 
formed over a concentric cylindrical inner wall 94 in a spaced apart 
relationship. Thus, in this embodiment, interior lumen 96 is provided by 
the space which is formed between the outer wall 92 and the inner wall 94. 
By way of further example and with reference now to FIGS. 9 and 10 in 
combination, the hub means is comprised of a first hub 98 joined in a 
fluid tight manner to the proximal end 90 of the cylindrical sleeve 86. 
First hub 98 further comprises, for example, a first passageway means, 
such as a first hub lumen (not shown), for communicating the fluid 
medicament to the interior lumen 96. As is shown in FIGS. 9 and 10, the 
first hub 98 can be attached, for example, to an external tube 100 through 
which the fluid medicament can be introduced to the internal lumen 96, as 
for example by syringe (not shown), via an infusion port 102. 
FIGS. 9 through 11 further illustrate the preferred embodiment of the 
plurality of one way valve means spaced along the cylindrical sleeve 86. 
As is shown, each valve means is comprised of a one way slit 104 that is 
formed through outer wall 92 of cylindrical sleeve 86. These slits 104 are 
preferably substantially identical to the one way slits 48 described above 
in connection with FIGS. 1 through 3. 
As is further shown in FIGS. 9 and 10, in this particular embodiment the 
sleeve 86 is further comprised of a means for selectively attaching and 
detaching the cylindrical sleeve 86 from the cannula 14. For example, 
selective attachment and detachment is illustrated as being accomplished 
by longitudinally sliding the hollow cylindrical sleeve 86 onto cannula 
14. The cylindrical sleeve 86 in such a mounted position is illustrated in 
FIGS. 10 and 11. 
When cylindrical sleeve 86 is thus mounted to cannula 14, the cylindrical 
inner wall 94 is in a continuous and tight fitting contact with the outer 
surface of cannula 14. The inner diameter of the cylindrical sleeve 86 
with respect to the outer diameter of cannula 14 is such that the sleeve 
86 remains positioned on the cannula 14 in a slidable, yet tight fitting 
manner. 
The sleeve 86 of this embodiment is also comprised of a means for sealing 
the sleeve 86 in a fluid tight manner around the cannula 14 so as to 
prevent fluids, such as blood from the body, from escaping between the 
cannula 14 and the sleeve 86. For example, as is shown in FIG. 9, this 
sealing means is accomplished by placing an O-ring 106 between the inner 
surface of the cylindrical sleeve 86 and the outer surface of the cannula 
14. Thus, when the cylindrical sleeve 86 is mounted to the cannula 14, 
O-ring 106 forms a fluid-tight seal, and thereby prevents any bodily 
fluids from leaking between sleeve 86 and cannula 14. Cylindrical sleeve 
86 also has formed thereon a suture attachment ring 47, similar to the 
ring 47 discussed above in connection with FIGS. 1 through 3. 
In the embodiment of FIGS. 9 and 10, the indwelling catheter apparatus 
further includes a second hub means, as for example hub 108, for providing 
fluid communication to the cannula 14. Hub 108 is joined in a fluid tight 
manner to proximal hub end 26 of cannula 14. As is also shown, hub 108 can 
be connected to external tube 110, through which fluids may be infused to 
cannula 14. 
As discussed, the cylindrical sleeves 56, 86 of the two embodiments of 
FIGS. 6 through 8 and 9 through 11 are not permanently mounted to any 
particular catheter device 12, but can be selectively attached and 
detached to preexisting catheter devices. Consequently, the versatility of 
a single cylindrical sleeve is greatly enhanced because it can be used 
with any one of a variety of catheter devices that are already on hand. 
Thus, when using a preexisting catheter device, medical personnel can 
retrofit the device with a cylindrical sleeve discussed in connection with 
FIGS. 6 through 11, and provide the patient with the pain relief that 
would not otherwise be available with that catheter device. Importantly, 
this retrofit capability provides the advantages of pain relief, yet 
simultaneously protects any investment already made in a stock of 
preexisting catheter devices. 
It will be appreciated that although the only difference between the 
embodiment of FIGS. 6 through 8 and the embodiment of FIGS. 9 through 11 
lies in how the cylindrical sleeve 56 or 86 is attached and detached to 
the cannula 14, the difference in how the two embodiments are used is more 
significant. In use, cylindrical sleeve 56 (FIGS. 6-8) attaches and 
detaches to the cannula 14 by way of the longitudinal slit 68 formed along 
the length of the sleeve 56. Thus, the sleeve 56 can be attached to a 
cannula 14 even if the cannula 14 has already been inserted in the 
patient. For instance, a doctor may insert a catheter device, such as an 
insertion sheath, perform the underlying procedure and, when completed, 
snap on the cylindrical sleeve 56 to the proximate portion of the cannula 
14. Since the patient is still locally anesthetized from the previously 
performed medical procedure, the sleeve 56 can then be inserted into the 
portion of subcutaneous tissue 20 with the cannula 14. When the cannula 14 
is later retracted (and the previously administered local anesthetic has 
worn off) the doctor can readminister a local anesthetic to the 
subcutaneous tissue 20 through sleeve 56 and then painlessly retract the 
cannula 14. In this way, the doctor or medical technician is not 
distracted by the extra equipment, tubes, infusion ports, etc. associated 
with cylindrical sleeve 56 while the underlying medical procedure, such as 
a PTCA, is being done. 
In contrast, cylindrical sleeve 86 (FIGS. 9-11) attaches and detaches to 
the cannula 14 by sliding the sleeve 86 onto the cannula 14. Consequently, 
the sleeve 86 of this embodiment cannot be placed on a cannula 14 that has 
already been inserted in a patient, and must necessarily be positioned on 
the cannula 14 before the underlying medical procedure is done and thus 
before cannula 14 is initially inserted into the patient. However, under 
certain circumstances this approach may be entirely acceptable and/or 
desirable. 
FIGS. 12 and 13 illustrate yet another embodiment of the indwelling 
catheter apparatus of the present invention, designated generally at 10d. 
As in the embodiments previously discussed, catheter apparatus 10d 
includes a catheter means, as for example a catheter device, which is 
essentially the same as the catheter device of the previous embodiments. 
The indwelling catheter apparatus 10d also has a sheath means for placement 
onto the cannula 14. By way of example and referring now to FIG. 12, 
sheath means is comprised of a helical sheath, designated generally at 
120. As is shown, helical sheath 120 is comprised of a single band 122 
that is wound in a helical fashion so as to conform to the cylindrical 
outer periphery of the cannula 14. The helical sheath 120 has a proximate 
end 124 and a distal end 126, and is preferably positioned on the cannula 
14 so that it can be disposed within the area of subcutaneous tissue 20 in 
conjunction with the cannula 14 (in the same manner illustrated in FIG. 
2). 
Referring now to FIG. 13, the band 122 that forms helical sheath 120 has a 
substantially flat cross-section when it is placed on the cannula 14. 
Further, when positioned on the cannula 14, band 122 has successive 
leading edges 128 and trailing edges 130 that are tapered with respect to 
the outer surface of the cannula 1.4. Advantageously, when the helical 
sheath 120 is mounted to the cannula 14, this flat cross-section and the 
tapered leading and trailing edges 128, 130 of band 122 act so as to ease 
the insertion and retraction of the helical sheath 120 through the 
patient's skin and subcutaneous tissue 20 when it is mounted to the 
cannula 14. Similarly, this configuration minimizes trauma to the skin or 
subcutaneous tissue 20 when the helical sheath 120 is inserted and 
retracted. 
Alternatively, FIG. 13A illustrates another cross-sectional shape that may 
be formed by band 122. In this embodiment, band 122 is placed on cannula 
14 in a tight helical fashion such that the leading edges 128 abut against 
the adjacent trailing edges 130. Further, each leading edge 128 slopes 
upwardly towards the trailing edge 130 to form an overall tapered shape. 
In this way, the helical sheath 120 has an overall tapered shape so as to 
permit easier insertion through the patient's skin and subcutaneous tissue 
20. 
Helical sheath 120 is further comprised of a fluid medicament delivery 
means for delivering a fluid medicament, such as an anesthetic agent, to 
the subcutaneous tissue 20 in which the helical sheath 120 is disposed. By 
way of example, FIGS. 12 and 13 illustrate how the fluid medicament 
delivery means is preferably comprised of a means for defining an interior 
lumen running from the distal end 126 to the proximal end 124 of helical 
sheath 120. As is shown, lumen means is comprised of an interior lumen 132 
that is defined by a hollow portion formed within band 122. The hollow 
portion that defines interior lumen 132 extends along the entire length of 
helical sheath 120. 
Helical sheath 120 is also preferably comprised of a hub means through 
which the anesthetic agent is delivered to the interior lumen 132. As FIG. 
12 illustrates, hub means is comprised, for example, of a tube 134 which 
is coupled in a fluid tight manner to the proximal end 124 of the helical 
sheath 120. Tube 134 has a single lumen 136 that is in fluid communication 
with the interior lumen 132. Anesthetic agent can be delivered to interior 
lumen 132 through a fluid injection port 138 connected to the opposite end 
of tube 134. FIG. 12 further illustrates how hub means also comprises, for 
example, a hub 135 that is connected in a fluid tight manner to the 
proximal hub end 26 of cannula 14. Hub 135 is essentially identical to hub 
108 discussed in connection with the embodiment of FIG. 10, and thus that 
discussion will not be repeated. 
With continued reference to FIG. 12, helical sheath 120 also comprises a 
plurality of one way valve means for communicating the anesthetic agent 
from the interior lumen 132 to the subcutaneous tissue 20 surrounding the 
sheath 120, and at the same time, for preventing bodily fluids, such as 
blood, from entering the interior lumen 132. For example, FIGS. 12 and 13 
illustrate how the valve means are each comprised of a one way slit 140 
that is formed through the band 122 to interior lumen 132. One way slits 
140 are placed uniformly along helical sheath 120, and are essentially 
identical to the one way slits discussed above in connection with the 
embodiments of FIGS. 1 through 11. 
As discussed generally, helical sheath 120 may further comprise a means for 
selectively attaching and detaching the helical sheath 120 to the cannula 
22. This function is provided by wrapping the helical sheath 120 onto the 
longitudinal length of cannula 14 so that the helical sheath 120 is 
concentrically positioned on the cannula, as is illustrated in FIG. 12. It 
will be appreciated that, like the embodiment of FIGS. 6 through 8, 
helical sheath 120 can be detachably mounted to a cannula 14 even after 
the cannula 14 has already been inserted into the patient. Preferably, the 
helical sheath 120 exhibits sufficient resilient properties such that once 
it is positioned on the cannula 14, it remains positioned in a tight 
fitting manner. Alternatively, once helical sheath 120 has been detachably 
mounted to the cannula 14, the medical technician may further adhere the 
sheath 120 to the cannula 14 by applying a small amount of liquid 
adhesive. Thus, helical sheath 120 can be selectively used on a variety of 
preexisting catheter devices. Alternatively, cannula 14 can be 
manufactured with a helical sheath 120 premounted in the manner 
illustrated in FIG. 12. In this instance, helical sheath 120 would be 
affixed permanently to the catheter device 12 by fusing, or similarly 
adhering it to the cannula 14. 
Referring now to FIGS. 14 through 16, yet another preferred embodiment of 
indwelling catheter apparatus, designated generally at 10e, is shown. 
Indwelling catheter apparatus 10e includes a catheter means, as for 
example a catheter device 12, that has a cannula 14 for insertion through 
subcutaneous tissue 20 into a patient's body (shown in FIG. 15). The 
catheter device 12 is essentially identical to the catheter device 
described in conjunction with the previous embodiments, having an 
indwelling distal end 17 and a proximal hub end 26. FIG. 15 further 
illustrates how cannula 14 is a cylindrical tube having a cylindrical 
outer wall 150, through which a primary lumen 152 runs. 
Indwelling catheter apparatus 10e also comprises a means for delivering a 
fluid medicament, such as an anesthetic agent, to essentially only the 
area of subcutaneous tissue 20 through which the cannula 14 is inserted. 
For example, in the embodiment of FIGS. 14 through 16, the means for 
delivering a anesthetic agent is comprised of a secondary lumen that is 
formed in the outer wall 150 of the cannula 14. FIGS. 15 and 16 illustrate 
how the secondary lumen is preferably comprised of a plurality of 
longitudinal bores 154 formed within the outer wall 150. as is further 
shown, the plurality of bores 154 are uniformly spaced about the 
circumference of the cannula 14, and each bore 154 is substantially 
parallel to the primary lumen 152 running through the cannula 14. Further, 
the plurality of bores 154 that form the secondary lumen are preferably 
formed in the cannula 14 outer wall 150 so that they are substantially 
disposed within the area of subcutaneous tissue 20 once the cannula 14 has 
been inserted within the patient's body. In this way, secondary lumen, as 
defined by the plurality of bores 154, can distribute the anesthetic agent 
to the subcutaneous tissue 20 evenly and uniformly. 
The anesthetic agent is communicated to the surrounding subcutaneous tissue 
20 from the secondary lumen 154 through a plurality of one way valve 
means, which also act to prevent bodily fluids from entering the secondary 
lumen 154. As FIG. 14 illustrates, the one way valve means are each 
comprised of a single one way slit 156 that is formed through the outer 
wall 150 to each of the plurality of longitudinal bores 154. This is 
illustrated in further detail in the exploded cross-section view of FIG. 
16, where one way slits 156 are illustrated. Each of the one way slits 156 
are substantially identical to the one way slits discussed above in 
connection with the other preferred embodiments. 
To deliver the anesthetic agent to the secondary lumen 154, the fluid 
medicament delivery means is further comprised of a hub means. This hub 
means is illustrated as being comprised of a single hub 158, that is 
joined in a fluid tight manner to the proximal hub end portion 27 of the 
cannula 14. FIGS. 14 and 15 illustrate how hub 158 is formed with a first 
hub lumen 42 and a second hub lumen 44. First hub lumen 42 is coupled to 
each of the longitudinal bores 154 that form the secondary lumen so as to 
provide a passageway for delivering anesthetic agent. Similarly, second 
hub lumen 44 is coupled to the primary lumen 152 via a cannula access hole 
46, thereby providing a separate fluid passageway for that lumen, As FIG. 
14 illustrates, the first and second hub lumens 42, 44 are connected to a 
multi-lumen tube 41, through which the first hub lumen 42 is connected to 
an infusion port 43, and second hub lumen 44 is connected to an I.V. valve 
assembly 45. Thus, anesthetic agent can be delivered to the bores 154 that 
form the secondary lumen with a syringe by using infusion port 43. 
The present invention may be embodied in other specific forms without 
departing from its spirit or essential characteristics. The described 
embodiments are to be considered in all respects only as illustrative and 
not restrictive. The scope of the invention is, therefore, indicated by 
the appended claims rather than by the foregoing description. All changes 
which come within the meaning and range of equivalency of the claims are 
to be embraced within their scope.