Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF THE INVENT:[ON
... . _ _ .
The present invention relates to adapter assemblies.
During certain medical procedures, for example a con-
tinuous epidural or caudal spinal anesthesia procedure, it is
necessary to connect a syringe to an end of a catheter. In a
continuous epidural anesthesia procedure, a needle is positioned
in a patient's body with an opening at one end of the needle posi-
tioned in the epidural space of the patient and with the other
end of the needle extending outside the patient's body. A cathe-
ter of relatively small diameter is threaded through the needle
and the needle opening until a distal end of the catheter is
located in the epidural space, while a proximal end of the cathe-
ter extends outside the patient's body. The needle is removed
from the patient's body and from the catheter to prevent obstruc-
tion if the operation takes place with the patient lying on his
back and to prevent the needle from cutting the catheter during
the operation. After removal of the needle, an anesthetic solu-
tion is injected through the catheter into the epidural space by
a syringe which is connected to the proximal end of the catheter.
Accordingly, a connector or adapter must be provided
for connecting the syringe to the proximal end of the catheter.
The adapter should be positionable on the catheter after removal
of the needle from the catheter, since the adapter would other-
wise prevent removal of the needle from the catheter. It is also
desirable that the adapter should permit easy placement on the
catheter to expedite the procedure.
After the syringe has been connected to the adapter,
the anesthetic solution is injected through the catheter into the
epidural space. A relatively large amount of the solution is ini-
tially required for epidural anesthesia, with additional amounts
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of the solution being periodically injected during surgery. It
is preferred that the syringe be removed from the adapter between
injections, since if the syringe remains connected to the adapter
and if the syringe inadvertently falls from the bed or other
structure on which it is placed, the weight of the connected syr-
inge may pull the catheter from the patient's body, necessitating
repositioning of the catheter into the epidural space during sur-
gery if further anesthesia is required.
SUMMARY OF THE INVENTION
A principal feature of the present invention is the
provision of a connector of simplified construction which facili-
tates attachment to the tip of a syringe and a catheter.
The connector comprises, a body member having an elon-
gated bore and an opening adjacent a distal end portion of the
body member communicating with the bore. The connector has an
elongated plug of elastic material received in the bore in a rela-
tively uncompressed condition of the plug. The plug has a channel
extending through the plug with the channel aligned with the body
member opening and with the internal dimensions of the channel
being slightly larger than the outer dimensions of the catheter.
The connector has a compression member having a nipple adjacent a
distal end of the compression member and receivable in a proximal
end portion of the body member. The compression member has a
port adjacent a proximal end portion of the compression member to
receive the syringe tip, and a passageway communicating between
the port and the distal end of the nipple, with a distal portion
of the passageway being aligned with the plug channel when the
nipple is received in the body member bore. The connector has
means for releasably attaching the compression member to the
body member with the nipple received in the bore, and for con-
trolling the distance the nipple projects into the bore.
A feature of the present invention is that the cathatermay be readily inserted through the body member opening and into
the plug channel while the plug is in its relatively uncompressed
condition.
Another feature of the invention is that the compres-
sion member may be attached to the body member such that communi-
cation is established between the syringe port and the plug chan-
nel.
Still another feature of the invention i8 that the dis-
tance which the compression member nipple extends into the body
member bore may be controlled such that the nipple bears upon
the plug and releasably locks the catheter in the plug channel.
Yet another feature of the invention is that the syr-
inge may be releasably attached to a proximal end portion of thecompression member with the syringe tip received in the compres-
sion member port.
Thus, a feature of the present invention is that the
catheter may be readily secured in the connector, and the syringe
may be attached to the connector in order to pump liquid through
the connector into the catheter.
A further feature of the invention is the provision of
a gripping element on the compression member which overlies a
proximal end portion of the body member in order to facilitate
removal of the syringe from the connector without releasing the
catheter from the compressed plug.
Further features will become more fully apparent in the
following description of the embodiments of this invention and
from the appended claims.
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DESCRIPTION OF THE DRAWINGS
_ _ _
In the drawings:
Fig. 1 is a fragmentary elevational view of an adapter
assembly of the present invention having a connector, a catheter,
and a syringe;
Fig. 2 is an exploded elevational view of the connec-
tor of Fig. l;
Fig. 3 is an exploded sectional view of the connector
of Fig. 2;
Fig. 4 is an end view of a compression member taken
substantially as indicated alony the line 4-4 of Fig. 3;
Fig. 5 is a sectional view of the connector with the
catheter received in a compressible plug of the connector;
Fig. 6 is a fragmentary elevational view, taken partly
in section, showing the catheter locked in the connector and the
syringe attached to the connector; and
Figs. 7 and 8 are diagrammatic views of a patient's
body illustrating steps during placement o~ a catheter in the
epidural space of the patient.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Re~erring now to Figs. 1-4, there is shown an adapter
assembly generally designated 10 comprising a syringe 12, a con-
nector 14, and an elongated relatively thin catheter 16 having
a lumen 18. The syringe 12 has a tip 20 communicating with a
chamber in a syringe barrel 22, and a luer fitment 24 for releas-
able attachment of the syringe to the connector 14.
The connector 14 has a body member 26 having an elon-
gated bore 28, an opening 30 at a dis-tal end 32 of the body mem-
ber 26, a pair of opposed outwardly directed wings 34 adjacent
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the distal end 32 of the body member 26, and internal threads 36
at the proximal end 38 of the body member 26. The connector 14
also has an elongated plug 40 of elastic material having a chan-
nel 42 extending longitudinally through the plug 40, with the
inner dimensions of the plug channel 42 being slightly larger
than the outer dimensions of -the catheter 16 when the plug 40 is
in a relatively uncompressed condition. As shown, both the plug
40 and the body member bore 28 have associated distal conical
sections and proximate cylindrical sections, such that the plug
40 may be received in a distal end portion 44 of the body member
bore 28 in a relatively uncompressed condition of the plug 40,
with the plug channel 42 being aligned with the body member open-
ing 30, and with the distal end of the plug channel 42 and the
body member opening 30 defining a distal taper to facilitate
placement of the catheter in the plug channel 42.
The connector 14 also has a compression member 46 hav-
ing a nipple 48 at a distal end 50 of the compression member 46.
The compression member 46 also has an outwardly directed luer
flange 52 at a proximal end 54 of the compression member 46, and
a tapered port 56 to receive the tapered syringe tip 20, such
that the syringe 12 may be releasably locked to the connector 14
through cooperation of the luer fitment 24 and the luer flange
52 with the syringe tip 20 being received in the connector port
56. The compression member 46 has a passageway 58 communicating
between the port 56 and an aperture 60 at the distal end 50 of
the compression member nipple 48 which defines a distal ring 61
surrounding the aperture 60. The compression member 46 has a
distally directed gripping element 62 which extends circumferen-
tially around the nipple 48, with the gripping element 62 being
connected to a mid-portion of the compression member 46 by a
~q~9~!L~'l
flange 64, such that the gripping element 62 and compression
nipple 48 define an annular cavity 66 for a purpose which will
be described below. As shown, the nipple 48 has outer threads
68 which cooperate with the threads 36 of the body member 26.
The body member 26 and compression member 46 may be
made of any suitable material, such as plastic. The plug 40 may
be made of any suitable elastic material, such as rubber or
Kraton, a trademark of Shell Oil Company.
The connector 14 is shown in an assembled configuration
in Fig. 5. Thus, the plug 40 is received in the distal portion
44 of the body member bore 28 in a relatively uncompressed condi-
tion of the plug, and the compression member 46 may be releasably
attached to the body member 26 through cooperation of the body
member threads 36 and the compression member threads 68, with the
proximal end 38 of the body member 26 being received in the cav-
ity 66 of the compression member 46 intermediate the gripping
element 62 and the nipple 48, and with the distal portion of
passageway 58 being aligned with the plug channel 42. In the
configuration of Fig. 5, the distal end of the nipple 48 slightly
contacts the proximal end of the plug 40, and a proximal end 70
of the catheter 16 may be readily inserted into the plug channel
42, since the plug 40 remains in a relatively uncompressed condi~
tion at this time. As previously noted, the distal taper of the
plug channel 42 and the body member opening 30 facilitates guid-
ance and placement of the catheter 16 into the plug channel 42.
With reference to Fig. 6, the compression member 46
may be further rotated relative the body member 26, such that the
cooperating threads cause distal movement of the compression mem-
ber nipple 48 in the body member bore 28. Thus, the distal ring
61 of the compression member nipple 48 bears upon the compressible
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plug 40 in order to reduce the effective size of the plug chan-
nel 42, causing the compressed plug to grip the catheter in the
plug channel 42 and lock the catheter in the connector 14. In
this configuration, the gripping element 62 overlies the proxi-
mal end 38 of the body member 26, with the proximal end 38 of
the body member 26 being received in the compression member cav
ity 66. At this time, the syringe 12 may be attached to the
proximal end of the compression member 46 in a manner as previ-
ously described.
Thus, the catheter may be readily inserted into the
plug channel 42 of the connector 14, and the catheter may be
locked in place by relative rotation of the compression member
46 and body member 26. Next, the syringe 12 may be attached to
the connector 14 in order to establish communication between the
syringe tip and the catheter lumen. In this manner, the connec-
tor 14 is attached to the catheter 16 in a simplified manner to
permit ejection of fluid into the catheter lumen when it is
desired to do so by attaching the syringe to the connector and
by pumping the syringe. However, after an initial quantity of
liquid has been ejectea from the syringe into the catheter lumen,
it is preferred to remove the syringe from the connector. The
physician may simultaneously grasp the gripping element 62 and
an exposed portion of the body member 26 with the fingers of one
hand, and the physician may then remove the syringe with the
other hand. Thus, the gripping element 62 permits removal of the
syringe 12 from the connector 14 while preventing rotation of the
compression member 46 relative the body member 26 which otherwise
might inadvertently release the catheter from the previously com-
pressed plug 40.
The use of the connector for a continuous epidural
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spinal anesthesia procedure is described in connection with Figs.
7 and 8 as follows, although it will be understood that the
assembly may be utilized for other suitable purposes, such as a
continuous caudal spinal anesthesia procedure. With reference
to Fig. 7, the tip T' of a ~ustead needle N is inserted through
the skin S' of the patient until an opening O in the needle tip
T' is located in the epidural space E. Next, a distal end 72
of the catheter 16 is threaded through the needle N and opening O
to position the distal end 72 of the catheter 16 in the epidural
space E, as shown. The desired length of the catheter distal end
16 located in the epidural space E may be determined by suitable
gradations spaced along the outer surface of the catheter. In
this configuration, the catheter 16 extends outside the patient's
body. The needle N is then removed from the patient's body and
from the catheter 16 to prevent the needle from inadvertently
cutting the catheter during surgery.
With reference to Fig. 8, after the needle has been
removed from the catheter, the proximal end 70 of the catheter
16 is inserted into the connector 14 and locked in place, in a
manner as previously described. Next, the syringe is attached
to the connector 14 to pump a quantity of anesthetic solution
from the syringe through the connector and catheter into the
spidural space E. When the desired amount of anesthetic solu-
tion has been injected into the epidural space, the syringe is
removed from the connector 14.
Accordingly, the adapter assembly permits easy place-
ment of the connector 14 on the proximal end 10 of the catheter
16. The syringe may be readily attached to the connector 14,
such that communication is established between the syringe and
the catheter 160 After the desired amount of solution has been
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injected into the epidural space, the syringe may be removed
from the connector.
The foregoing detailed description is given for clear-
ness of understanding only, and no unnecessary limitations should
S be understood therefrom, as modifications will be obvious to
those skilled in the art.
