U.S. patent number 3,656,486 [Application Number 05/026,727] was granted by the patent office on 1972-04-18 for instrument for inserting a suprapubic catheter.
Invention is credited to Jack R. Robertson.
United States Patent |
3,656,486 |
Robertson |
April 18, 1972 |
INSTRUMENT FOR INSERTING A SUPRAPUBIC CATHETER
Abstract
An instrument having a curved distal portion insertable through
the urethra into the bladder to bring the distal end of the
instrument into engagement with the anterior wall of the bladder in
register with the suprapubic area of the abdominal wall. After
inflating the bladder with a suitable fluid through a longitudinal
passage in the instrument and a lateral opening in the curved
distal portion thereof, an incision is made through the abdominal
wall and the anterior wall of the bladder in register with the
distal end of the instrument, which then emerges outwardly through
the incision. The distal end of the instrument is provided with a
recessed catheter engaging means engageable with a tip portion of a
retention catheter and adapted to insert the tip portion of the
catheter into the bladder through the incision. Thereafter, the
instrument is disengaged from the catheter within the bladder and
is then withdrawn from the bladder and the urethra, leaving a
portion of the catheter within the bladder. The catheter is then
inflated to retain it within the bladder.
Inventors: |
Robertson; Jack R. (Santa Ynez,
CA) |
Family
ID: |
21833458 |
Appl.
No.: |
05/026,727 |
Filed: |
April 8, 1970 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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297 |
Jan 2, 1970 |
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Current U.S.
Class: |
606/108;
604/915 |
Current CPC
Class: |
A61M
25/10 (20130101); A61M 25/01 (20130101); A61M
2025/0191 (20130101) |
Current International
Class: |
A61M
25/10 (20060101); A61M 25/01 (20060101); A61m
025/00 () |
Field of
Search: |
;128/303,305,311,328,341,343,347,348,350,3-8,349R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Truluck; Dalton L.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of my copending
application Ser. No. 297, filed Jan. 2, 1970.
Claims
I claim as my invention:
1. An instrument for inserting a suprapubic catheter, said
instrument having a curved distal portion terminating in a distal
end insertable through the urethra into the bladder and through an
incision in the anterior wall of the bladder and the overlying
suprapubic area of the abdominal wall to the exterior of the body,
said instrument having a longitudinal passage therein from its
proximal end toward its distal end and having a lateral opening
therein adjacent and communicating with the distal end of said
passage, said instrument having catheter engaging means at its
distal end engageable with a tip portion of a retention catheter
for inserting such tip portion of the catheter through the incision
into the bladder, said catheter engaging means being disengageable
from the catheter within the bladder, said catheter engaging means
being recessed to receive therein at least a part of the tip
portion of the catheter, said instrument being a tube from its
proximal end to its distal end and being provided with a closure at
its distal end, and said tube being closed at a point spaced from
the distal end of said instrument and between the distal end of
said instrument and said lateral opening.
2. An instrument for inserting a suprapubic catheter, said
instrument having a curved distal portion terminating in a distal
end insertable through the urethra into the bladder and through an
incision in the anterior wall of the bladder and the overlying
suprapubic area of the abdominal wall to the exterior of the body,
said instrument having a longitudinal passage therein from its
proximal end toward its distal end and having a lateral opening
therein adjacent and communicating with the distal end of said
passage, said instrument having catheter engaging means at its
distal end engageable with a tip portion of a retention catheter
for inserting such tip portion of the catheter through the incision
into the bladder, said catheter engaging means being disengageable
from the catheter within the bladder, said catheter engaging means
being recessed to receive therein at least a part of the tip
portion of the catheter, said catheter engaging means comprising a
hook insertable into a lateral opening in the tip of the catheter,
said hook being inclined laterally outwardly and rearwardly toward
the proximal end of said instrument, and having its tip spaced
laterally from the instrument, so that it can be disengaged from
the tip of the catheter within the bladder by a slight movement of
said instrument relative to the catheter tip, said catheter
engaging means including a longitudinally extending channel into
which said hook projects laterally and rearwardly, and a sloping
cam surface at the rearward or proximal end of said channel which
is engageable by the tip of the catheter in response to a slight
movement of said instrument to assist in disengaging said hook from
the catheter tip.
3. An instrument for inserting a suprapubic catheter, said
instrument having a curved distal portion terminating in a distal
end insertable through the urethra into the bladder and through an
incision in the anterior wall of the bladder and the overlying
suprapubic area of the abdominal wall to the exterior of the body,
said instrument having a longitudinal passage therein from its
proximal end toward its distal end and having a lateral opening
therein adjacent and communicating with the distal end of said
passage, said instrument having catheter engaging means at its
distal end engageable with a tip portion of a retention catheter
for inserting such tip portion of the catheter through the incision
into the bladder, said catheter engaging means being disengageable
from the catheter within the bladder, said catheter engaging means
comprising means for receiving therein and gripping a part of an
inflatable portion of the catheter when same is partly inflated,
and said receiving and gripping means comprising a socket having an
inwardly extending protrusion engageable with the inflatable
portion of the catheter.
Description
BACKGROUND OF INVENTION
The present invention relates in general to catheters and, more
particularly, to an instrument for inserting a retention catheter,
such as a Foley, mushroom, Malekot, or similar catheter, from a
suprapubic location.
Postoperative bladder drainage by way of a retention catheter
inserted into the bladder through the urethra has long been
conventional. However, urethral insertion has serious
disadvantages, among these being a high incidence of urinary tract
infection, urethral irritation and swelling making normal urination
difficult or impossible, extreme pain upon withdrawing a catheter
which has been in place for some time, and the like.
Such disadvantages of urethral insertion can be eliminated or
minimized by insertion through a small suprapubic incision, a
technique of relatively recent development and one which is being
used progressively more extensively. However, prior suprapubic
insertion techniques leave much to be desired.
For example, one prior suprapubic insertion technique involves
making a blind puncture through the abdominal wall and into the
bladder with a trocar after filling the bladder with a suitable
fluid, such as water, through a urethral catheter. Subsequently, a
retention catheter is threaded through the trocar into the bladder.
This procedure has various disadvantages, not the least of which is
the inherent hazard involved in making a blind puncture. Another
disadvantage of this process is that the catheter, being insertable
through the trocar, is sufficiently smaller than the incision made
by the trocar that leakage of urine can occur around the
catheter.
Another prior suprapubic insertion technique involves: filling the
bladder with water, or other suitable fluid, through a urethral
catheter, which is then removed; subsequently inserting through the
urethra and into the bladder a rigid instrument having a curved
distal portion the end of which is brought into engagement with the
anterior wall of the bladder to form a visible outward protrusion
of the suprapubic area of the abdominal wall; making a small
incision through the abdominal wall and the anterior wall of the
bladder in register with the distal end of the instrument,
whereupon the distal end of the instrument may be displaced
outwardly through the incision; connecting a wire withdrawn from
the instrument to the distal end of a retention catheter; pulling
the instrument, with the catheter attached thereto by the wire,
through the incision, the bladder and the urethra; disengaging the
catheter from the wire; and then pulling the catheter back through
the urethra and into the bladder. This procedure, while less
objectionable in some respects to the blind puncture technique,
creates problems of its own. Among these are the excessive
irritation resulting from repeated passes through the urethra, with
the attendant possibility of infection, and the contamination of
the portion of the catheter which is withdrawn through the
suprapubic incision in pulling the distal portion of the catheter
back through the urethra and into the bladder.
SUMMARY AND OBJECTS OF INVENTION
Generally speaking, an important object of the present invention is
to provide a suprapubic catheter insertion instrument which, when
used with the proper technique, avoids the hereinbefore-discussed
problems and disadvantages associated with prior suprapubic
insertion techniques and equipment.
More particularly, an important object of the invention is to
provide an instrument which eliminates any necessity for a blind
puncture, and which further eliminates any necessity for repeated
passes through the urethra.
Another and important object in the foregoing connection is to
provide an instrument which requires only a single insertion
through the urethra and a single withdrawal therefrom, thereby
greatly minimizing urethral irritation and the attendant
possibility of infection.
Another object of importance is to provide an instrument usable in
such a manner that only the portion of the retention catheter which
is required to be within the bladder is ever inserted thereinto
through the suprapubic incision, thereby avoiding contamination of
the external portion of the catheter.
Yet another object is to provide an instrument which requires an
incision no larger than, or smaller than, the portion of the
retention catheter to be received in the incision, which portion
may be narrowed by stretching, thereby minimizing the possibility
of leakage of urine around the catheter.
Still another object of the invention is to provide an instrument
capable of functioning both as a catheter and as a trocar.
The invention may be summarized as comprising an instrument for use
in suprapubic catheter insertion technique which includes:
inserting through the urethra and into the bladder a curved distal
portion of a rigid instrument having one or more lateral openings
adjacent its distal end and a longitudinal passage extending from
its proximal end to such openings; inflating the bladder with
water, or other suitable fluid, through the instrument; engaging
the distal end of the instrument with the anterior wall of the
bladder with sufficient force to provide a visible protrusion of
the suprapubic region of the abdominal wall; making a small
incision through the abdominal wall and the anterior wall of the
bladder in register with the distal end of the instrument;
displacing the distal end of the instrument outwardly through the
incision, this occurring automatically in most instances as the
result of the outward pressure applied by the instrument; engaging
a tip portion of a retention catheter with a catheter engaging
means at the distal end of the instrument; displacing the catheter
engaging means and a portion of the catheter into the bladder
through the incision; disengaging the catheter engaging means from
the tip portion of the catheter within the bladder; withdrawing the
instrument from the bladder and the urethra, leaving a portion of
the catheter within the bladder; and inflating the inflatable
portion of the catheter within the bladder to insure retention.
Another and important object of the invention is to provide an
instrument having the characteristics set forth in the foregoing
summation.
Another object is to provide a catheter engaging means which is
recessed to receive at least a part of the tip portion of the
catheter therein.
An important object in connection with the presently preferred
species of the invention is to provide a catheter engaging means
having a channel to receive the catheter tip and a rearwardly
slanting, rounded hook insertable into a lateral opening in the
catheter tip. With this construction, the instrument can be
unhooked from the catheter tip within the bladder very readily by a
slight movement of the instrument relative to the catheter tip,
which is an important feature.
An object in connection with another embodiment is to provide a
catheter engaging means comprising a longitudinal socket in the
distal end of the instrument and adapted to receive the catheter
tip, insertion into the bladder through the incision being
accomplished with the assistance of a catheter probe for stiffening
the catheter. A removable closure normally closes the socket in the
distal end of the instrument.
An object related to still another embodiment is to provide a
catheter engaging means having a recess to receive a part of the
inflatable portion of the catheter, and having means to grip such
inflatable portion frictionally when it is partly inflated.
The foregoing objects, advantages, features and results of the
present invention, together with various other objects, advantages,
features and results thereof which will be evident to those skilled
in the catheter art in the light of this disclosure, may be
achieved with the exemplary embodiments of the invention
illustrated in the accompanying drawings and described in detail
hereinafter.
DESCRIPTION OF DRAWINGS
In the drawings:
FIGS. 1 to 3 are fragmentary sectional views illustrating
semidiagrammatically successive steps involved in the preferred
technique of inserting a retention catheter into a patient's
bladder through a suprapubic incision in the abdominal wall and the
anterior wall of the bladder using an alternative embodiment of the
instrument of the invention;
FIG. 4 is a longitudinal sectional view illustrating the instrument
used in the technique shown in FIGS. 1 to 3;
FIG. 5 is a fragmentary longitudinal sectional view of another
alternative instrument of the invention;
FIG. 6 is a fragmentary side elevational view of an instrument
constituting the presently preferred embodiment of the
invention;
FIG. 7 is an elevational view taken as indicated by the arrowed
line 7--7 of FIG. 6;
FIG. 8 is a longitudinal sectional view taken as indicated by the
arrowed line 8--8 of FIG. 7;
FIG. 9 is an end view, taken from the left as viewed in FIG. 8;
FIG. 10 is an elevational view of still another embodiment of the
invention;
FIG. 11 is a longitudinal sectional view taken as indicated by the
arrowed line 11--11 of FIG. 10; and
FIG. 12 is a transverse sectional view taken as indicated by the
arrowed line 12--12 of FIG. 11 of the drawings.
DESCRIPTION OF EXEMPLARY EMBODIMENTS OF INVENTION
Figs. 1 to 4
Referring initially to FIG. 4 of the drawings, illustrated
fragmentarily therein is an instrument 10 of the invention which,
in view of the functions it performs, may be termed a
"cysto-trocar-catheter." The functioning of the instrument 10 as
both a catheter and a trocar will become evident in the course of
describing the procedure in which it is used.
The instrument 10 comprises simply a rigid tube 12, of metal,
plastic, or other suitable material, having a proximal end 14
equipped with a grip or handle 13 provided with a tubing connector
15 which communicates with the interior of the tube 12. A straight
or substantially straight intermediate portion 16 terminates in a
curved distal portion 18 having a distal end 20. The curved distal
portion 18 is provided adjacent the distal end 20 with one or more
lateral openings 22 which communicate with the distal end of the
longitudinal passage formed by the tube 12 and leading to the
tubing connector 15. The distal end 20 is provided with a removable
closure 24 which is rounded externally so that the closure may act
as an obturator facilitating insertion of the distal end 20 and the
curved distal portion 18 through a patient's urethra 26, FIGS. 1 to
3, and into the patient's bladder 28. The closure 24 may be
removably secured to the distal end 20 of the instrument 10 by
threading it thereinto. Alternatively, the closure 24 may be
threaded onto the distal end 20, or it may be pressed into or onto
the distal end, etc.
In the particular construction illustrated, the instrument 10 is of
a diameter and a length suitable for use with female patients.
However, it may be used with male patients by suitably modifying
its length and diameter, and also its curvature.
Considering the technique with which the instrument 10 of the
invention is used, the distal end 20 of the instrument is first
inserted through the urethra 26 into the bladder 28, into the
position shown in FIG. 1, for example. Then, a suitable fluid, such
as water, is introduced into the bladder 28, through the tube 12
and the lateral openings 22, in a quantity sufficient to inflate or
distend the bladder, as shown in FIG. 1 of the drawings. This may
be accomplished readily by connecting a fluid source 30 to the
tubing connector 15 by means of an elastomeric tube 32 equipped
with a clamp 34. As will be apparent, fluid for distending the
bladder 28 may be introduced by disengaging the clamp 34. When the
bladder has been distended to the proper degree, the clamp 34 is
reengaged with the elastomeric tube 32 to prevent further fluid
introduction and to prevent reverse flow.
It will be apparent that, in the foregoing operations, the
instrument 10 functions as an urethral catheter.
The next step, also shown in FIG. 1, is to bring the closed distal
end 20 of the instrument 10 into engagement with the anterior wall
of the bladder with sufficient force to provide a visible external
protrusion 36 in the suprapubic region 38 of the abdominal wall 40.
This can be accomplished readily by suitable manipulation of the
instrument 10 by means of the handle 13.
The visible external protrusion 36 produced by the foregoing
manipulations locates the closed distal end 20 of the instrument
very accurately. Next, the physician, utilizing a scalpel 42, or
other appropriate cutting instrument, makes a small incision, at
the center of the protrusion 36, through the abdominal wall 40 and
the anterior wall of the bladder 28. Normally, this incision need
not be more than of the order of 2 to 4 millimeters in length.
The incision through the abdominal wall 40 and the anterior wall of
the bladder 28, which incision is designated generally by the
numeral 44 in FIGS. 2 and 3 of the drawings, is made while
maintaining the closed distal end 20 of the instrument 10 in
pressural engagement with the anterior bladder wall. Consequently,
when the incision 44 is sufficiently large, the closed distal end
20 is automatically displaced outwardly through the incision. In
practice, the closed distal end 20 simply pops into view when the
incision is large enough. Thus, the instrument 10 performs its
aforementioned trocar function.
Once the closed distal end 20 of the instrument 10 has emerged
through the suprapubic area 38 of the abdominal wall 40, the
closure 24 is removed, as by unscrewing it, or otherwise removing
it, as shown in FIG. 2.
Continuing to refer to FIG. 2 of the drawings, the physician next
takes a retention catheter 50 and inserts at least the tip portion
42 thereof into the distal end 20 of the instrument 10. To stiffen
the catheter 50 for insertion of the portion 52 thereof into the
distal end 20 of the instrument, a catheter probe 54 is inserted
through the drainage branch 56 of the catheter into the tip
portion.
Next, the physician inserts the catheter 50 through the incision 44
into the bladder 28 by an inward force applied to the catheter, as
stiffened by the probe 54. At the same time, the distal end 20 of
the instrument 10 is withdrawn through the incision 44 into the
bladder 28. It will be understood that such movement of the
instrument-catheter combination may readily be carried out by
concurrent movement of the physician's hands. In effect, the
instrument-catheter combination is threaded through the patient's
body by the physician, with one hand on the instrument 10 and the
other on the probe-stiffened catheter 50, until the catheter has
been inserted to the required extent. The catheter 50 is provided
with external indicia, not shown, indicating the depth of
insertion.
After the catheter 50 has been inserted to the proper extent, the
instrument 10 is withdrawn from the bladder 28 and the urethra 26,
as shown in FIG. 3. Thereafter, the inflatable portion 58 of the
catheter 50 is inflated through the inflation branch 60 of the
bifurcated device. The inflated portion 58 then retains the tip
portion 52 within the bladder 28 in draining communication with the
interior thereof.
Although the instrument 10 of the invention has been disclosed in
connection with a Foley catheter, it will be understood it may be
employed with any catheter capable of being retained in position
once inserted. It will also be understood that if the physician
desires to run the catheter 50 all the way through the patient's
body for any reason, this can be done without contamination by
pushing or pulling it through the tubular instrument 10. It may be
pushed through by means of the catheter probe 54, or pulled through
by a wire, not shown, threaded through the drainage openings in the
tip portion 52 of the catheter.
Reviewing some of the advantages of the instrument 10 of the
present invention, which advantages also apply to the instruments
described hereinafter, it will be apparent that it minimizes
urethral irritation since the only operations involving the urethra
are insertion and subsequent withdrawal of the instrument
therethrough. Another advantage is that the suprapubic incision 44
is made with the protrusion 36 formed by the closed distal end 20
of the instrument 10 as a positive reference, thereby avoding all
of the hazards inherent in making a blind or obscured puncture or
incision. As previously pointed out, it is necessary only to make
an incision large enough to permit the instrument to act as a
trocar. In view of the smallness of the incision, and the fact that
the outside diameter of the portion of the catheter 50 to be
disposed in the incision can be about the same as the outside
diameter of the instrument itself, or even larger if it is
stretched during insertion by means of the catheter probe 54, the
tissues surrounding the incision engage the catheter snugly to
prevent urine leakage around the outside of the catheter.
Another distinct advantage of the invention is that the entire
procedure hereinbefore discussed can be carried out without an
assistant, which is an important feature.
Fig. 5
this figure of the drawings illustrates an instrument 80 which is
virtually identical to the instrument 10 and which includes a tube
82 having a distal end 84 closed by a removable closure 86. The
instrument 80 differs in that the tube 82, instead of being open
throughout, is closed adjacent its distal end 84 by a partition 88
between the distal end 84 and lateral openings 90 communicating
with the distal end of the longitudinal passage 92 formed by tube
82. On the other side of the partition 88 is a longitudinal socket
94 for the closure 86, or a catheter tip.
The instrument 80 is used in the same way as and has the same
advantages as the instrument 10 so that no further description is
necessary.
In the instrument 10, the distal end 20 of the tube 12 acts as a
recessed catheter engaging means for receiving therein the tip 52
of the catheter 50 during insertion into the bladder 28. Similarly,
the distal end 84 of the tube 82 of the instrument 80 acts as such
a recessed catheter engaging means. Different catheter engaging
means are embodied in the instruments illustrated in FIGS. 6 to 12
of the drawings, as will now be described.
Figs. 6 to 9
In these figures of the drawings is illustrated an instrument 100
which is generally similar to the instruments 10 and 80 in that it
is provided with a curved distal portion 102 terminating in a
distal end 104. The instrument 100 is provided with a longitudinal
passage, not shown, from its proximal end, not shown, to one or
more lateral openings 106 corresponding to the analogous lateral
openings in the instruments 10 and 80.
The instrument 100 includes a catheter engaging means having the
form of a catheter engaging tip 110 provided at its proximal end
with a reduced-diameter stem 112 pressed into the distal end of the
tubular body portion of the instrument. The catheter engaging tip
110 is what might be termed generally spoon shaped and, in cross
section, has the configuration of an arcuate channel 114 which
extends longitudinally to the distal extremity thereof. The channel
is of a size and shape to receive a catheter tip 116, FIG. 8, and
terminates at its rearward or proximal end in an inclined cam
surface 118. Within the channel 114 intermediate its ends is a
rearwardly inclined hook 120 the end of which is rounded to
minimize urethral irritation, the length of the hook being less
than the diameter of the catheter tip for the same reason. As shown
in FIG. 8, the hook 120 is so located and proportioned as to be
insertable into a lateral opening 122 in the catheter tip 116. The
instrument 100 may be used with any catheter having a tip provided
with such a lateral opening.
The technique involved in using the instrument 100 is generally
similar to that described previously. Once the necessary suprapubic
incision has been made, in the manner hereinbefore set forth, and
the catheter engaging tip 110 has emerged through the incision, the
physician engages the catheter tip 116 with the hook 120 by
inserting the latter into one of the lateral openings 122 in the
catheter tip. Then, by slowly withdrawing the instrument 100
through the urethra, the catheter engaging tip 110 guides and
inserts the catheter tip 116 into the bladder through the
suprapubic incision, by drawing it into the bladder through the
incision. As soon as the catheter has been inserted the desired
distance, the physician can unhook the catheter engaging tip 100
from the catheter tip 116 readily, within the bladder, by a slight
motion of the instrument 100 relative to the catheter tip in a
direction to disengage the hook 120 from the opening 122. In the
process of unhooking the instrument 100 from the catheter tip 116,
the cam surface 118 engages the extremity of the catheter tip and
assists in the unhooking process. Thereupon, the instrument 100 may
be withdrawn from the bladder through the urethra. The catheter,
not shown, with which the catheter tip 116 is associated is
retained in the bladder in any known manner, as by inflating an
inflatable portion thereof in the manner hereinbefore
discussed.
As will be apparent, the instrument 100 itself is all that is
necessary to insert the catheter into the bladder, it being
unnecessary to rely on a catheter probe, or the like, for
assistance. Thus, a catheter can be inserted into a bladder through
a suprapubic incision much more simply with the instrument 100. In
all other respects, the instrument 100 operates in the same way as
and has all of the advantages of the instrument 10. Consequently, a
further discussion herein is unnecessary.
Figs. 10 to 12
These figures of the drawings show fragmentarily an instrument 130
which is similar to the instruments 10, 80 and 100 and which
includes a curved distal portion 132 terminating in a distal end
134 carrying a catheter engaging means or tip 136 having a stem 138
pressed into a longitudinal socket in the distal end of the body
portion of the instrument.
In this case, the catheter engaging tip 136 is provided therein
with a longitudinal socket 140 and terminates in a distal end 142
inclined at an accute angle to the axis of the tip. The socket 140
is of a diameter and length to receive therein a catheter tip 144,
FIG. 11, having an inflatable portion 146. A part of the inflatable
portion 146 is disposed within the socket 140 axially inwardly of a
radially inwardly projecting annular protrusion or rib 148. When
the part of the inflatable portion 146 axially behind the annular
rib 148 is inflated slightly, it is gripped and prevented from
withdrawal from the socket 140 by the annular rib 148.
The instrument 130 is used in generally the same way as the
instrument 10. After the catheter engaging tip 136 has emerged
through the suprapubic incision, the catheter tip 144, and part of
the inflatable portion 146 thereof, are inserted into the socket
140 in the catheter engaging tip 136, and axially behind the
annular rib 148. The inflatable portion 146 of the catheter tip 144
is then inflated sufficiently for the annular rib 148 to grip the
catheter tip securely. Thereupon, the instrument 130 is drawn
outwardly through the urethra until the catheter engaging tip 136
and the catheter tip 144 gripped thereby are pulled through the
suprapubic incision into the bladder. Once the catheter has been
inserted into the bladder through the suprapubic incision to the
required extent, the inflatable portion 146 thereof is deflated to
disengage the catheter from the catheter engaging tip 136 within
the bladder. Thereupon, the instrument 130 is withdrawn from the
bladder and the urethra, and the inflatable portion 146 is inflated
to its normal extent to retain the catheter within the bladder. In
all other respects, the instrument 130 has the same mode of
operation and the same advantages as the instrument 10 so that no
further discussion is required herein.
Although exemplary embodiments of the invention have been disclosed
for purposes of illustration, it will be understood that various
changes, modifications and substitutions may be incorporated in
such embodiments without departing from the scope of the invention
as set forth in the claims appearing in the next section
hereof.
* * * * *