 |
Claims  |
|
|
What is claimed is:
1. A combined inserting and cleaning stylet for use with a retention
drainage catheter adapted to be inserted into and retained in the bladder
for the continuous drainage of waste material therefrom, the catheter
being an elongate flexible cannula having an open and unobstructed distal
end to communicate the interior of the bladder with a drainage lumen
extending through the cannula from the distal end thereof to the exterior
of the urethra, the cannula also having means on an inner wall surface of
the drainage lumen adjacent the distal end defining a portion of the
drainage lumen of different diameter than the rest of the drainage lumen
thereby forming an abutment for the stylet, said stylet comprising:
A. an elongate flexible body member of substantially uniform diameter
throughout a major portion of its length,
B. means adjacent one end of said body member defining a portion thereof of
different diameter than the rest of the body member and defining an
abutment means adapted to engage with the abutment means disposed in the
cannula when said stylet is inserted therein,
C. a tapered tip element defining a minor portion of the length of said
body member, said tip element having a relatively smooth rounded end,
D. means removably connecting said tip element to the other portion of said
body member, and
E. a brush element adapted to be connected to said other portion of said
body member after said tip element is removed therefrom,
whereby said stylet is used to insert the catheter by cooperating
engagement between said abutment means on said stylet and the abutment
means in the cannula, and thereafter is used to clean the cannula by
removing said tip element from said other portion of said body member and
thereafter connecting said brush element thereto.
2. A stylet as set forth in claim 1 wherein said body member includes a
drainage passageway extending throughout the length thereof through which
waste material can flow thereby providing an indication of when said
tapered tip portion of said stylet has entered the bladder.
3. A retention drainage catheter adapted to be inserted into and retained
in the bladder for the continuous drainage of waste material therefrom,
and a stylet for inserting the retention drainage catheter through the
urethra and into the bladder, said catheter and stylet comprising in
combination:
A. an elongate flexible cannula formed of a flexible and pliant material
having both distal and proximal ends, the length of said cannula being
such that said distal end is disposed within the bladder and the proximal
end is disposed exteriorily of the urethra, said cannula having
1. a drainage lumen extending from said distal end substantially to said
proximal end,
2. means formed on the inner tubular wall of said drainage lumen defining
an abutment means adjacent said distal end of said cannula, and
3. expandable means connected to said cannula adjacent said distal end
thereof for retaining said distal end within the bladder after passing
through the urethra,
4. said distal end of said cannula defining an unobstructed opening the
cross-sectional area of which is substantially equal to the
cross-sectional area of said drainage lumen and which lies in a plane
substantially perpendicular to the longitudinal axis of said drainage
lumen whereby waste material in the bladder flows directly into said
drainage lumen at said distal end of said cannula and instrumentation is
introduced into the bladder through said drainage lumen, and
B. an elongate flexible stylet adapted to be inserted through said drainage
lumen, said stylet being longer than said cannula and having
1. at least a major portion of its length of s substantially uniform
diameter which will pass through said drainage lumen,
2. means formed adjacent one end of the stylet defining an abutment means
for engagement with said abutment means in said drainage lumen, and
3. a tip portion having a smooth rounded end normally projecting beyond
said the distal end of said cannula
whereby said catheter is inserted through the urethra by pushing said
catheter therethrough by engagement of the abutment means on said cannula
and said stylet until said expandable means enters the bladder to retain
said cannula in place, after which said stylet is withdrawn from said
cannula.
4. The combination as set forth in claim 3 wherein said stylet includes a
longitudinal drainage passageway extending therethrough from said tip
portion exteriorily of the urethra through which waste material flows when
said tip portion enters the bladder to provide an indication that the
distal end of the stylet has entered the bladder and the relative location
of the distal end of the cannula.
5. The combination as set forth in claim 3 wherein
A. said means defining said abutment means on said cannula comprises an
annular boss projecting radially inwardly of said drainage lumen, and
B. said means defining said abutment means on said stylet comprises a
radial boss projecting outwardly from said stylet,
both said bosses having cooperating abutment surfaces which engage when
said stylet is inserted into said cannula.
6. The combination as set forth in claim 5 wherein said cannula is tapered
adjacent said distal end thereof to form a gradually widening portion from
said distal end to facilitate passage of said cannula through the urethra,
and wherein said annular boss on said cannula is located adjacent the
widest point of said gradually widening portion so that only said
gradually widening portion of said cannula is pushed ahead of said
abutment means during insertion of the catheter through the urethra.
7. The combination as set forth in claim 3 wherein
A. said means defining said abutment means on said cannula comprises an
annular recess formed in said cannula and projecting radially outwardly
from said drainage lumen, and
B. said means defining said abutment means on said stylet comprises a
radial projection extending outwardly from the surface of said stylet,
both said recess and said projection having forwardly slanting barb-like
cooperating abutment surfaces which engage when said stylet is inserted
into said cannula.
8. The combination as set forth in claim 7 wherein said cannula is tapered
adjacent said distal end thereof to form a gradually widening portion from
said distal end, and said recess on said cannula is located adjacent the
widest point of said gradually widening portion so that only said
gradually widening portion of said cannula is pushed ahead of said
abutment means during insertion of the catheter through the urethra.
9. A retention drainage catheter adapted to be inserted into and retained
in the bladder for the continuous drainage of waste material therefrom,
and a stylet for inserting the retention drainage catheter through the
urethra and into the bladder, said catheter and stylet comprising in
combination:
A. an elongate flexible cannula formed of a flexible and pliant material
having both distal and proximal ends, the length of said cannula being
such that said distal end is disposed within the bladder and the proximal
end is disposed exteriorily of the urethra, said cannula having
1. a drainage lumen extending from said distal end substantially to said
proximal end,
2. means formed on the inner tubular wall of said drainage lumen defining
an abutment means adjacent said distal end of said cannula, and
3. expandable means connected to said cannula adjacent said distal end
thereof for retaining said distal end within the bladder after passing
through the urethra,
4. said distal end of said cannula being open and unobstructed whereby
waste material in the bladder flows directly into said drainage lumen at
said distal end of said cannula and instrumentation is introduced into the
bladder through said drainage lumen,
B. an elongate flexible stylet adapted to be inserted through said drainage
lumen, said stylet being longer than said cannula and having
1. at least a major portion of its length of a substantially uniform
diameter thiwh will pass through said drainage lumen,
2. means formed adjacent one end of the stylet defining an abutment means
for engagement with said abutment means in said drainage lumen, and
3. a tip portion having a smooth rounded end normally projecting beyond
said distal end of said cannula,
C. said means defining said abutment means on said cannula comprising a
pair of spaced apart annular bosses projecting inwardly of said drainage
lumen, the boss adjacent said distal end projecting further inwardly than
the other boss, and
D. said means defining said abutment means on said stylet comprising a pair
of spaced apart bosses projecting outwardly from said stylet, the boss
remote from said distal end of said stylet projecting further outwardly
than the other boss,
E. the smaller of said bosses on said stylet being of a diameter to pass
the larger of the bosses on said cannula but said bosses otherwise having
cooperating abutment surfaces,
F. said bosses on said stylet being spaced to have the abutment surfaces
thereof farther apart than the corresponding abutment surfaces of said
bosses on said cannula,
whereby said catheter is inserted through the urethra by pushing said
catheter therethrough by engagement of the abutment means on said cannula
and said stylet until said expandable means enters the bladder to retain
said cannula in place, after which said stylet is withdrawn from said
cannula, and during insertion of the catheter through the urethra as
aforesaid, if the forwardmost abutment surfaces slip past each other the
rearwardmost abutment surfaces will engage after said stylet moves
forwardly in said cannula to continue the insertion of said catheter.
10. The combination as set forth in claim 9 wherein said cannula is tapered
adjacent said distal end thereof to form a gradually widening portion from
said distal end, and wherein said smaller and rearwardly disposed of said
annular bosses on said cannula is located adjacent the widest point of
said gradually widening portion and said larger and forwardly disposed of
said annular bosses on said cannula is located within said gradually
widening portion so that only said gradually widening portion of said
cannula is pushed ahead of said abutment means during insertion of the
catheter through the urethra regardless of which said pairs of abutment
surfaces is engaged.
11. A retention drainage catheter adapted to be inserted into and retained
in the bladder for the continuous drainage of waste material therefrom,
and a stylet for inserting the retention drainage catheter through the
urethra and into the bladder, said catheter and stylet comprising in
combination:
A. an elongate flexible cannula formed of a flexible and pliant material
having both distal and proximal ends, the length of said cannula being
such that said distal end is disposed within the bladder and the proximal
end is disposed exteriorily of the urethra, said cannula having
1. A drainage lumen extending from said distal end substantially to said
proximal end,
2. means formed on the inner tubular wall of said drainage lumen defining
an abutment means adjacent said distal end of sand cannula, and
3. expandable means connected to said cannula adjacent said distal end
thereof for retaining said distal end within the bladder after passing
through the urethra,
4. said distal end of said cannula being open and unobstructed whereby
waste material in the bladder flows directly into said drainage lumen at
said distal end of said cannula and instrumentation is introduced into the
bladder through said drainage lumen,
B. an elongate flexible stylet adapted to be inserted through said drainage
lumen, said stylet being longer than said cannula and having
1. at least a major portion of its length of a substantially uniform
diameter which will pass through said drainage lumen,
2. means formed adjacent one end of the stylet defining an abutment means
for engagement with said abutment means in said drainage lumen, and
3. a tip portion having a smooth rounded end normally projecting beyond
said distal end of said cannula,
C. said means defining said abutment means on said cannula comprising a
pair of spaced apart annular recesses formed in said cannula and
projecting outwardly from said drainage lumen, the recess remote from said
distal end of said cannula projecting farther outwardly than the other
recess, and
D. said means defining said abutment means on said stylet comprising a pair
of spaced apart radial projections extending outwardly from the surface of
said stylet, the projection remote from said distal end of said stylet
projecting further outwardly than the other projection,
E. both said pairs of recesses and projections having forwardly slanting
barb-like cooperating surfaces which engage when said stylet is inserted
into said cannula,
F. the smaller of said projections on said stylet being of a diameter to
pass the larger of the recesses on said cannula but said projections and
recesses otherwise having cooperating abutment surfaces,
G. said projections on said stylet being spaced to have the abutment
surfaces thereof farther apart than the corresponding abutment surfaces of
said recesses on said cannula,
whereby said catheter is inserted through the urethra by pushing said
catheter therethrough by engagement of the abutment means on said cannula
and said stylet until said expandable means enters the bladder to retain
said cannula in place, after which said stylet is withdrawn from said
cannula, and during insertion of the catheter through the urethra, if the
forwardmost abutment surfaces slip past each other the rearwardmost
abutment surfaces will engage after said stylet moves forwardly in said
cannula to continue insertion of the catheter.
12. The combination as set forth in claim 11 wherein said cannula is
tapered adjacent said distal end thereof to form a gradually widening
portion from said distal end, and wherein said farther outwardly
projecting recess on said cannula is located adjacent the widest portion
of said gradually widening portion and said other recess is located within
said gradually widening portion of said cannula so that only said
gradually widening portion of said cannula is pushed ahead of said
abutment means during insertion of said catheter through the urethra
regardless of which of said pairs of abutment surfaces is engaged. |
|
 |
|
 |
Claims |
|
|
|
Description |
|
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
It is well recognized in the field of Urology that persons lose control of
their urinary function. This loss of control may be temporary or
permanent, depending upon the cause of the loss of urinary function.
Temporary loss may be caused by a disease entity which is curable by
medical or surgical treatment, whereas permanent loss of control may be
caused by an incurable disease entity or physical trauma resulting in
partial or total paralysis of the muscles which cause normal urination.
The bladder is a dome shaped container with muscular walls and which
accepts urine from the kidneys for temporary storage. During normal
voluntary urination, the muscles in the bladder wall contract and
simultaneously the sphincter muscle surrounding the opening in the bladder
which communicates with the urethra relaxes so that the urine stored in
the bladder is released into the urethra and expelled from the body.
The causes for loss of normal voluntary control of the urination process
are manifold and the consequences are indeed severe. If urine cannot be
periodically expelled from the bladder, the urine becomes stagnant and
bacteria multiply at an exceedingly rapid rate, resulting in infection of
the bladder. Chemical changes in the urine due to the infection cause
painful urination and can also cause general dibilitation of health. If,
after infection occurs, the urine retention is still permitted to continue
for any considerable length of time beyond normal voluntary urination
frequency, ascending infection can occur, that is the infection in the
bladder spreads to the ureters and to the kidneys, thereby causing still
more serious consequences, such as failure of one or both of the kidneys
to function. If the kidneys do not function to cleanse the blood of
impurities and form urine, uremia results and death occurs in the absence
of the availability of recently developed artificial kidney machines. If,
on the other hand, the kidneys continue to function and fill the
non-draining bladder with urine, the bladder can burst, thereby emptying
the bacteria laden urine into the abdominal cavity. The usual result of
this is peritonitis, which is an inflammation of the peritoneum, the
membrane that lines the abdominal cavity, and the results of inflammation
of this membrane are always serious. The time between the occurrence of
acute peritonitis and death may be only a matter of a few hours to a few
days depending upon the severity of the infection. Septicemia, an
infection of the blood, is another serious consequence of excessive
retention of urine in the bladder, since the bacteria in the bladder,
ureters and kidneys invades the blood through the minute blood capillaries
in these organs.
Obviously other complications, bodily disorders and disfunctions and
serious consequences, too numerous to mention herein, can result from
failure of proper urination. It is obvious that constant periodic drainage
of the bladder to eliminate urine and other body waste material is
essential not only to good health but to maintaining life itself.
Techniques of treatment for loss of normal voluntary control of the
urination process are relatively few in number. Depending on the nature of
the cause, a super-pubic technique involving surgery may eliminate the
drainage problem in some circumstances. Since surgery is involved, this
treatment is traumatic and severe, and is utilized only when absolutely
necessary. Drug therapy is effective in some cases to promote drainage of
the bladder, but due to the relatively few causes of loss of voluntary
control which will respond to drugs and the ever presence of undesirable
side effects, drug therapy is considered to be a relatively ineffective
method of dealing with the problem.
2. Necessity for Practice of Invention
Since the loss of voluntary control over the urinary function is typically
a secondary effect caused either by disease or trauma, it has become a
well established medical practice to relieve the urinary drainage problem
mechanically by means of the process of catheterization. If the primary
cause of the loss of voluntary urination control is from a curable
disease, the catheterization process is maintained on a temporary basis
only for so long as necessary until voluntary control returns. If the
cause of loss of control is permanent, as in the case of paralysis such as
with paraplegics and quadriplegics, the catheterization process must be
maintained on a permanent basis in order to maintain life.
In the catheterization process, a tube or catheter is inserted into and
through the urethra until the remote or distal end is located within the
bladder, usually being disposed just past the sphincter muscle at the
juncture of the bladder with the urethra. The near or proximal end of the
tube remains outside of the body and there is thus provided a path or
channel through which urine in the bladder can drain as the need arises.
Once a catheter has been passed through the urethra and inserted into the
bladder, it is generally necessary, in connection with the disease and
trauma conditions described above, to have the catheter retained in the
urinary tract with the distal end of the catheter in the bladder, such
retention being in the order of several days to several weeks without
removal. Catheters which are designed for use a function are called
urinary retention catheters and are typically provided by including an
inflatable balloon at the distal end of the catheter which is deflated
during insertion of the catheter and which is inflated by passing a fluid,
typically water or saline solution through a passage within the catheter,
called an inflation lumen. Thereafter, fluid from the bladder drains
through the main passage of the catheter, called the drainage lumen.
PROBLEMS OF CATHETERIZATION
Inserting a catheter into the urethra can be a painful and traumatic
experience, the degree of pain and trauma depending on the construction of
the catheter being inserted, the technique for inserting it, and the
experience and the skill of the person performing the insertion whether
that person is the doctor or other individual. Since the designers of
catheters have no control over the last named characteristic, the present
invention has been developed with the first two characteristics
principally in mind, but also with consideration for the fact that the
catheter may on many occasions be inserted by other individuals who would
not be as skilled as the doctor. The reason for possible pain and trauma
is that the urethra, whether male or female, is a relatively tortuous tube
of varying cross-sectional dimensions and is normally collapsed along most
of its length. The upper portion of the urethra is provided with
sphincters or valves which it enters the bladder neck. The female urethra
is somewhat shorter and straighter than the male urethra but otherwise
both are much the same. The urethra is a very delicate organ and cannot
withstand any appreciable amount of lateral pressure against the urethral
wall without causing some degree of rupture. Since the urethra has a high
concentration of pain sensing nerve endings, any distortion, whether of
change in size or shape, is very uncomfortable at the least and usually
painful, and any trauma to the urethra is accompanied by a great deal of
pain. It is not uncommon for the patient to have to be anesthetized in
order to insert many common urinary catheters. In addition to the pain,
bacteria in the urethra can enter the blood stream if the urethra is
traumatized, with the same result discussed above in connection with
rupture of the bladder.
Extensive research and development have been carried out over a long period
of time in the design of catheters, and a large number of different
catheter designs appear in the medical and patent literature. The reason
for this is that design characteristics for urinary drainage catheters are
highly conflicting from the standpoints of patient discomfort and
functionalism. In order to reduce the probability of trauma and resulting
pain to the urethra as well as discomfort to the patient during long
periods of retention, a urinary drainage catheter should be as thin as
possible, highly flexible and pliant, and have a soft rounded end. From
the functional standpoint, on the other hand, the catheter must be of
sufficiently thick and rigid construction that it will not buckle while
being passed through the urethra, it should have as wide a drainage
opening and lumen as possible to promote complete drainage and prevent
clogging, and the end should be free and unobstructed in order to
facilitate the use of the catheter as an aid to the insertion of
diagnostic and treatment instrumentation into the bladder. Of great
importance is the fact that a retention catheter must have an effective
means for retaining the catheter in place in the bladder which will not
obstruct either the flow of urine or substantially the complete drainage
of urine therefrom, but at the same time has sufficient retaining
capability that a patient, particularly a senile patient, cannot forcibly
pull the catheter out of the bladder and into the urethra thereby causing
extreme damage thereto. Further, any urinary drainage catheter must be
formed of a material totally inert to the effects of urine and other waste
materials, be capable of absolute sterilization, and be manufacturable to
strict tolerances, in high volume and at low cost considering the
disposable nature of the product. Still other criteria may be apparent to
those skilled in the art.
THE PRIOR ART
In view of the foregoing diverse criteria, the basic design of commercially
available retention catheters has changed very little over the past half
century, and the well known Foley retention catheter is almost universally
used by doctors, hospitals, nursing homes, etc. to alleviate loss of
voluntary bladder control. U.S. Pat. Nos. 2,892,458; 2,936,761; 3,292,627
and 3,394,705 are mentioned as illustrating typical prior art catheters
which are usually formed of relatively thick walled construction so as to
be insertable without buckling, have a rounded solid tip to prevent trauma
to the delicate lining of the urethra, and have side openings adjacent the
tip to communicate the interior of the bladder with the drainage lumen.
The prior art catheters also have an inflatable balloon portion beyond the
drainage opening in order to retain the catheter in place. These
catheters, and many more like them, are undesirable from the standpoint
that considerable pain may be experienced in introducing a relatively
wide, semi-rigid catheter into a relatively narrow urethra. Further, the
small side openings can easily clog from clots of sediment material which
collects in the bottom of the bladder. Still further, as a result of the
solid tip, it is impossible to pass diagnostic or treatment
instrumentation through the catheter for the purpose of inspecting or
treating the interior of the bladder. The capability of inserting
instrumentation through the catheter after it is in place is very
important in the urological practice since prior treatment involves the
use of anesthesia in order to insert steel tube instrumentations as has
been the practice.
In U.S. Pat. No. 2,677,375, recognition was given to the desirability of
removing the fixed rounded tip so as to provide a drainage opening
adjacent the inflatable retention balloon. Strips are provided across the
opening for engagement by an inserting stylet. This construction is
disadvantageous in that the strips likely to obstruct the passage of
sediment clots and thus clog the drainage opening, and even more harmful
is the fact that the insertion of such a blunt end as is apparent in this
device is almost certain to cause considerable trauma to the delicate wall
of the urethra. It is also apparent that is would be at least difficult,
if not impossible, to pass instrumentation through this catheter in view
of the strips across the open end. Such a device would be wholly
unacceptable to the urological practitioner.
A significant aspect of the presention invention is the provision of an
improved stylet which is utilized both during insertion of the catheter
through the urethral passage and thereafter as a cleaning implement. U.S.
Pat. Nos. 2,118,631; 2,164,926 and 2,856,934 are cited as representative
of prior art stylets which are utilized solely to assist in inserting the
catheter, the first two being of the typical push rod type and the third
being of the filiform type. Although the use of a stylet to insert the
catheter obviates the problem of bucking of the catheter during insertion
and thereby permits the catheter to have a relatively thin wall
construction, the push rod type used in conjunction with a closed end
catheter is undesirable from the standpoint that there is no way of
accurately ascertaining when the end of the catheter enters the bladder
because the stylet blocks the drainage opening or the drainage lumen or
both. The filiform device is undesirable because of the possibility of
injuring the delicate wall of the urethral passage during the insertion of
the filiform unless great care is exercised because of the fact that the
filiform is of necessity very thin and therefore must be relatively rigid
and sharp nosed. Other disadvantages of this technique for inserting
drainage catheters will be apparent to those skilled in the art.
Another significant improvement of the present invention is the novel
construction of the inflatable retention balloon to cause the open end of
the catheter to expand and widen, which assists in drainage and in
retention. Some consideration has been given to this problem as evidenced
by U.S. Pat. No. 2,892,458 mentioned above, as well as by U.S. Pat. No.
3,438,375 and 3,889,686. In the first patent, the balloon is constructed
to be less inflatable adjacent the lateral drainage opening through the
catheter wall so that the balloon cannot overlie and block the opening if
the catheter tends to settle in the bladder or is pulled by the patient.
In U.S. Pat. No. 3,438,375, the opposite theory is applied and the balloon
is constructed to purposely overlie the lateral drainage but be spaced
therefrom so that the delicate lining of the bladder cannot be drawn into
the opening by sub-atmospheric pressure. In U.S. Pat. No. 3,889,686, a
lateral opening is provided below the balloon as well as above so as to
promote better drainage. All of these techniques have inherent
disadvantages in that they present design problems which are difficult to
overcome in manufacturing the catheter, they are not nearly as effective
in practice as eliminating the lateral drainage opening altogether so that
the inflation balloon presents no interference problem whatever, and they
cannot function to allow movement of a stylet to indicate when the balloon
is inflated because the rounded tip closes the longitudinal end of the
drainage lumen.
SUMMARY OF THE INVENTION
The present invention substantially obviates if not completely eliminates
many of the disadvantages of prior art and commercially available urinary
retention catheters and also provides advantages and desirable features
not heretofore obtainable with such catheters.
The principles of the present invention are embodied in a novel urinary
drainage catheter, a novel stylet for use with the catheter and in a novel
cooperation in the combination of the catheter and the stylet together.
In general, the catheter comprises an elongate cannula formed preferably
although not necessarily of a plurality of layers of flexible and pliant
materials, the inner and outer layers being of relatively soft latex
rubber and an intermediate layer being of relatively thinner but stronger
silicone rubber. The cannula has both distal and proximal ends, the length
of the cannula being such that the distal end is disposed within the
bladder and the proximal end is disposed exteriorly of the urethra when
the catheter is in operative position in the body. The cannula has an
inner tubular wall surface defining a drainage lumen which extends from
the distal end substantially to the proximal end. The distal end is open
and unobstructed so as to communicate the interior of the bladder directly
with the full cross-sectional area of the drainage lumen. There is means
on the inner tubular wall adjacent the distal end which defines a portion
of the drainage lumen of slightly different diameter than the diameter of
the rest of the drainage lumen, which means forms an abutment for the
stylet used to insert the catheter. The catheter also includes an
expandable means preferably in the form of an inflatable balloon connected
to the inner and outer layers of the cannula adjacent the distal end for
retaining the distal end in the bladder and for expanding the distal end
of the cannula so as to widen the opening and to dispose the end of the
cannula lower in the bladder than it is with the balloon uninflated. In
one embodiment, the abutment forming means forms a hinge about which the
distal end expands and the abutment means distorts to a shape which allows
the stylet to pass beyond the abutment means and move freely back and
forth for at least a limited distance, thereby providing an indication
that the balloon has inflated.
The stylet comprises generally an elongate flexible body member of
substantially uniform diameter throughout a major portion of its length.
Adjacent one end of the body member is means defining a portion of
different diameter than the diameter of the body member and defining an
abutment surface adapted to engage with the abutment means disposed in the
cannula when the stylet is inserted therein. The stylet is provided with a
tapered tip element on the end adjacent the abutment surface, the tip
element having a relatively smooth rounded end. The tip element is
removably connected to the end of the body member so that it can be
removed from the body member after the stylet is withdrawn from the
catheter, and a brush element is provided which is connectable to the body
member for cleaning the catheter. Both the body member and the tip element
have a central bore of relatively small diameter so that the flow of urine
therethrough affords a positive indication that the distal end of the
catheter has entered the bladder.
Having briefly described the general nature of the present invention, a
principal object thereof is to provide a retention drainage catheter and
stylet for use therewith which avoids the disadvantages of prior art
constructions and provides advantages not heretofore attainable in devices
of this nature.
Another object of the present invention is to provide a retention drainage
catheter and stylet for use therewith which avoids to the fullest possible
extent any likelihood of injury to the urethra during insertion of the
catheter.
Another object of the present invention is to provide a retention drainage
catheter and stylet for use therewith which is designed to render
insertion relatively simple and with a minimum of discomfort so that the
insertion process can be carried out without the need for anesthesia.
Another object of the present invention is to provide a retention drainage
catheter and stylet for use therewith in which the catheter and stylet
have a cooperating abutment relationship by which the stylet is used to
insert the catheter into the bladder and which does not interfere with the
free flow of urine or other waste materials through the catheter.
Another object of the present invention is to provide a retention drainage
catheter and a stylet for use therewith in which the entire full width
portion of the catheter is pulled through the urethra rather than a
portion thereof being pushed therethrough.
Another object of the present invention is to provide a retention drainage
catheter which is constructed to provide the widest possible drainage
opening from the bladder directly into the drainage lumen of the catheter
in order to minimize if not altogether prevent clogging of the drainage
opening due to sediment material collecting in the bladder.
Another object of the present invention is to provide a retention drainage
catheter through which various types of instrumentation may be passed into
the bladder for performing diagnostic or treatment techniques therein.
Another object of the present invention is to provide a retention drainage
catheter having a novel inflatable retention balloon construction which
causes the distal end of the catheter to expand to provide a still wider
drainage opening whic | | |
