Syringe pump abstract
A system is provided for accommodating the use of a syringe pump
to inject a liquid agent into a patient from a vial having an internal
chamber occluded at one end by a stopper located in the chamber
to sealingly engage the vial and slide within the chamber. The system
includes a plunger having a bearing end to be engaged by a movable
pushing member of the syringe pump and having a drive end adapted
to engage the stopper. A hollow piercing needle is mounted to the
plunger to be connected in fluid communication with the patient
and has a piercing end to penetrate the stopper. The needle moves
with the plunger and stopper relative to the chamber as the liquid
is discharged from the vial.
Syringe pump claims
What is claimed is:
1. A system for injecting a liquid agent into a patient comprising:
a vial defining an internal chamber having a closed end and an
open end, said open end having a stopper slidably mounted therein,
said stopper fluidly sealing said internal chamber;
a plunger comprising a substantially annular wall and an end wall
mounted on a first end portion of said substantially annular wall,
said substantially annular wall and said end wall defining a chamber,
said substantially annular wall having a drive end portion mounted
on a second end portion thereof, said drive end portion constructed
to engage said stopper, said drive end portion of said substantially
annular wall constructed to enter said open end of said vial; and
a hollow piercing needle mounted on said plunger within said chamber
defined by said substantially annular wall and said end wall, said
hollow piercing needle having a piercing end constructed to penetrate
said stopper, said hollow piercing needle fluidly connected to a
first end portion of a tube, said tube having a second end portion,
said substantially annular wall of said plunger defining a channel
therethrough at a position spaced from said hollow piercing needle,
said tube passing through said channel defined through said substantially
annular wall of said plunger, said hollow piercing needle and said
tube defining a fluid flow path from said internal chamber to a
point external to said internal chamber.
2. The system in accordance with claim 1 in which said plunger
comprises two identical, mating pieces.
3. The system in accordance with claim 1 wherein said system further
a curved guide surface positioned within the substantially annular
wall of said plunger, and wherein said tube extends over said curved
guide surface prior to passing through said channel defined by said
substantially annular wall.
4. A system for injecting a liquid agent into a patient comprising:
a vial defining an internal chamber having a closed end and an
open end, said open end having a stopper slidably mounted therein,
said stopper fluidly sealing said chamber;
a plunger comprising two mating pieces, each said mating piece
defining an aperture having an adjacent lug and a tab having a latching
surface, said mating pieces constructed such that one mating piece
is received in the aperture of the other mating piece and such that
each latching surface engages the lug of the other mating piece,
said plunger having a substantially annular wall defining a chamber
therein, said substantially annular wall having a drive end portion
constructed to engage said stopper, said drive end portion of said
substantially annular wall constructed to enter said open end of
said vial; and
a hollow piercing needle mounted on said plunger within said annular
wall, said hollow piercing needle having a piercing end constructed
to penetrate said stopper, said hollow piercing needle fluidly connected
to a first end portion of a tube, said tube having a second end
portion, said second end portion of said tube defining a fluid flow
path to a point external said plunger, said hollow piercing needle
and said tube defining a fluid flow path from said internal chamber
to a point external to said internal chamber.
5. A system in accordance with claim 4 wherein each of said mating
pieces further comprises a pin and a bore, and wherein the pin of
one mating piece is received in the bore of the other mating piece.
Syringe pump description
The present invention relates to apparatus for providing a liquid
agent to a patient by means of a standard parenteral infusion syringe
pump. The apparatus is particularly well-suited for accommodating
the intravenous administration of liquids, including drugs.
BACKGROUND OF THE INVENTION AND
TECHNICAL PROBLEMS POSED BY THE PRIOR ART
Conventional syringe pumps are typically employed with either a
syringe or a vial and plunger system for administering a liquid
agent to a patient. In such conventional systems, a syringe or vial
of the liquid agent is oriented vertically in a fixed position on
the syringe pump. The bottom of the syringe or vial defines a discharge
port connected to a flexible, hollow tubing which extends to the
patient and which has a suitable cannula at the distal end for insertion
into the patient's vein.
The plunger or piston of the apparatus is engaged with the moving
pusher plate or drive member of the syringe pump and is driven downwardly
into the syringe body or vial to force the liquid agent from the
syringe body or vial through the tubing and into the patient.
While such systems function generally satisfactorily, it would
be desirable to provide an improved liquid agent container and delivery
system. It would also be advantageous if such an improved system
could be employed with certain conventional vials and with various
conventional syringe pumps, especially the newer syringe pumps which
require smaller maximum diameter syringes.
Additionally, it would be desirable if an improved system could
provide the capability for purging air from the system while the
system apparatus is mounted in the syringe pump in a normal, elevated,
vertically oriented position.
It would also be beneficial if such an improved system could accommodate
the use of a relatively low-cost glass vial having a single opening.
It would be advantageous if such an improved system could also
optionally accommodate the use of plastic vials (especially where
plastic/liquid contact is acceptable).
It would also be desirable if an improved system could incorporate
a relative low-cost short needle plunger design having a more convenient
overall dispensing height or length.
Finally, it would be desirable to provide an improved system that
could accommodate designs having a reduced number of closures, such
as rubber stoppers, with which the liquid agent is in contact.
The present invention provides an improved system for administration
of a liquid agent to a patient with a syringe pump wherein the system
can accommodate designs having the above-discussed benefits and
SUMMARY OF THE INVENTION
The present invention, in its preferred form, permits the use of
a pre-filled and sterilized container (e.g., a glass vial) to be
used in a conventional syringe pump. It is especially advantageous
for liquid agent products that are only stable in glass containers.
However, the present invention may also be employed with plastic
The novel apparatus of the present invention permits the system
to be purged of air while it is mounted in the pump in its normal
dispensing position. This simplifies the air purging process.
According to one aspect of the present invention, a system is provided
for accommodating the use of a syringe pump to inject a liquid agent
into a patient from a vial having an internal chamber which is occluded
at one end by a stopper located in the chamber to sealingly engage
the vial and slide within the chamber.
The system includes a plunger having a bearing end to be engaged
by a movable pushing member of the syringe pump. The plunger has
a drive end adapted to engage the stopper. The drive end is sized
to enter the vial chamber as the stopper is pushed by the plunger
while the vial is held stationery in the syringe pump.
A hollow piercing needle is mounted to the plunger. The needle
is connected in fluid communication with the patient and has a piercing
end which penetrates the stopper. After the needle has penetrated
the stopper, the needle subsequently moves with the plunger and
stopper relative to the chamber as the liquid is discharged from
According to another aspect of the present invention, at least
one type of conventional vial can be adapted for use with the system
by attaching a flange to the vial. The flange engages a stationary
receiving structure on the syringe pump.
In a preferred embodiment, tubing is connected to the base of the
needle and extends generally upwardly away from, and out of, the
top of the vial as the plunger moves further into the vial. The
tubing is bent around an upper portion of the plunger and from there
extends down to the patient.
Numerous other advantages and features of the present invention
will become readily apparent from the following detailed description
of the invention, from the claims, and from the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings that form part of the specification,
and in which like numerals are employed to designate like parts
throughout the same,
FIG. 1 is a perspective view of a vial containing a liquid agent;
FIG. 2 is a view similar to FIG. 1 but FIG. 2 shows the vial cap
removed to expose a stopper having a threaded upper end;
FIG. 3 is a view similar to FIG. 1 but FIG. 3 shows the attachment
of a flange to the upper end of the vial;
FIG. 4 is a view similar to FIG. 3 but FIG. 4 shows the cap removed
from the flanged vial;
FIG. 5 is a view of the vial of FIG. 4 shown engaged with the dispensing
system of the present invention, and FIG. 5 shows portions of the
vial cut away to illustrate interior detail and shows portions of
one of the components of the dispensing system plunger cut away
to illustrate interior detail;
FIG. 6 is a greatly enlarged, perspective view of one piece of
the two-piece plunger which is shown in FIG. 5; and
FIG. 7 is a reduced, side elevational view of the plunger of FIG.
5 shown in partial cross section to illustrate interior detail.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
While this invention is susceptible of embodiment in many different
forms, this specification and the accompanying drawings disclose
only one specific form as an example of the invention. The invention
is not intended to be limited to the embodiment so described, however.
The scope of the invention is pointed out in the appended claims.
For ease of description, the components of this invention are described
in a typical operating position, and terms such as upper, lower,
horizontal, etc., are used with reference to this position. It will
be understood, however, that the components of this invention may
be manufactured, stored, transported, used, and sold in an orientation
other than the position described.
Figures illustrating the apparatus of the invention show some mechanical
elements that are known and that will be recognized by one skilled
in the art. The detailed descriptions of such elements are not necessary
to an understanding of the invention, and accordingly, are herein
presented only to the degree necessary to facilitate an understanding
of the novel features of the present invention.
The components of this invention are used with certain conventional
equipment (e.g., a syringe pump, tubing, connectors, etc.) the details
of which, although not fully illustrated or described, will be apparent
to those having skill in the art and an understanding of the necessary
functions of such components.
The system of the present invention may be employed in the administration
of a liquid agent from a variety of containers. One such container
is a vial 10 illustrated in FIG. 1. The vial 10 is a conventional
glass vial sold in the U.S.A. as part of the ABBOJECT.RTM. brand
unit of use packaging systems for use with syringe pumps by Abbott
Laboratories, Inc., One Abbott Park Road, Abbott Park, Ill. 60064-3500
The vial 10 includes a glass cylindrical container 12 having a
closed bottom and an open top which is sealed with an internal piston-type
stopper 14 and which is additionally covered with a removable cap
As illustrated in FIG. 2 the stopper 14 includes a resilient,
sealing piston portion 30 which is sealingly engaged with the interior
circumference of the container 12. The piston portion 30 includes
a plurality of rings 32 spaced by grooves 34.
A post 36 projects upwardly from the piston portion 30 and is a
unitary part of the stopper 14. The post may include a helical thread
The cap 16 includes a transverse end wall 40 and a reduced diameter
lower skirt 42 for being received within the container 12.
In a preferred embodiment, the ABBOJECT.RTM.brand vial is modified
by adding a flange 46 (FIG. 3). The flange 46 can be relatively
inexpensively molded for use with the vial 10 or with any other
suitable vial or container.
The flange 46 includes a pair of oppositely extending wing portions
48 and a pair of spaced-apart saddle members 50 which provide stability
for mounting and attaching the flange 46 to the exterior, cylindrical
surface of the vial container 12.
As presently contemplated, the vial 10 is initially prepared at
a manufacturing facility by filling the vial with a desired quantity
of liquid agent 52 and by subsequently inserting the stopper 14
and cap 16. Then the flange 46 is installed. Any suitable attachment
system may be employed. One contemplated attachment system uses
an ultraviolet radiation curable adhesive or epoxy. Proper attachment
of the flange 46 does not interfere with subsequent removal of the
cap 16 and with subsequent access to the stopper 14.
According to the present invention, the modified vial 10 can be
employed with a conventional syringe pump for administering the
liquid agent 52 to a patient. To this end, the present invention
provides a plunger 60 (FIG. 7) and a hollow piercing needle 64 10
mounted to the plunger. The plunger and needle are adapted to engage
the vial 10.
In particular, the plunger 60 includes, in a preferred form, two,
identical, molded, thermoplastic pieces 66 and 68 (FIG. 7). The
plunger piece 66 is shown greatly enlarged in FIG. 6. The piece
66 has a generally semi-cylindrical configuration with an upper
bearing end plate 70. As viewed in FIG. 6 the right- hand vertical
edge of the piece 66 includes three latch tabs 72 and each latch
tab extends toward the right beyond the cylindrical exterior surface
of the piece 66 to define a generally planar latch surface 74 (facing
away from the observer as viewed in FIG. 6).
On the left-hand vertical edge of the piece 66 (as viewed in FIG.
6), the piece 66 defines three lugs 78 which extend outwardly (to
the left as viewed in FIG. 6) from the cylindrical surface of the
piece 66. The lugs 78 each define an aperture 80 for receiving an
inserted latch tab 72 of the mating piece 68. The outer edge of
each lug 78 extends rearwardly (as viewed in FIG. 6) for a distance
which is longer than the depth of the insertion of the tab 72. However,
the wall of the lug 78 is undercut adjacent the aperture 80 to provide
a ledge for engaging the latch surface 74 of the tab 72.
The right-hand vertical edge of the piece 66 also defines three
bores 82 and the left-hand vertical edge of the piece 66 defines
three projecting pins 86.
The plunger piece 68 is identical with the plunger piece 66 described
above with reference to FIG. 6. When the plunger pieces 66 and 68
are placed together as shown in FIG. 7 to form the generally cylindrical
plunger 60 the latch tabs 72 of one piece are received in the apertures
80 of the other piece, and the pins 86 of one piece are received
in the bores 82 of the other piece. The latch tabs 72 are sufficiently
resilient to accommodate a temporary, inward deformation so that
the latch surface 74 of each latch tab 72 passes through the associated
aperture 80 and then snaps outwardly behind the lug 78 adjacent
the aperture 80 to effect a secure, snap-fit engagement.
The pins 86 may be adhesively secured within the mating bores 82.
Alternatively, external heating elements may be applied to an external
depression 90 (FIG. 7) behind each bore and pin to effect an interface
melting of the thermoplastic material. Subsequent cooling results
in a resolidified heat seal bond.
The internal configuration of each plunger piece 66 and 68 is identical.
With reference to the plunger piece 66 illustrated in FIG. 6 it
is seen that the plunger piece 66 includes a generally transversely
oriented, semi-cylindrical guide wall 94. Two angled retaining walls
96 extend outwardly from the top surface of the guide wall 94 and
each retaining wall 96 defines a notch 98 for receiving tubing as
Adjacent the curved surface 94 the sidewall of the plunger piece
66 defines a pair of opposed slots or channels 99. These channels
99 accommodate the extension of connecting tubing (described hereinafter)
out of the plunger.
In the lower portion of the plunger piece 66 there is a unitary
needle hub mounting structure 102 which includes a pair of spaced-apart,
vertically oriented walls 104 (FIG. 6). This receives the needle
64 as described in detail hereinafter. The walls 104 are joined
by central cross wall 108 which defines a horizontal groove 110
and a vertical groove 116. A short, vertical, middle wall 120 extends
downwardly between the walls 104 from the lower surface of the cross
wall 108 and the wall 120 functions as a rigidifying structure.
A plurality of vertical ribs 124 are provided on the interior surface
of the plunger piece 66 below the needle hub mounting structure
The needle 64 is mounted in a conventional hub 130 (FIG. 5). The
top of the hub 130 terminates in an outwardly extending, horizontal
flange 132. The horizontal flange 132 is received in the horizontal
groove 110 in the wall 108 and a portion of the hub 130 below the
flange 132 is received in the vertical groove 116 below the horizontal
groove 110 in the wall 108.
The conventional needle hub 130 is attached to thermoplastic tubing
140 in a well-known manner. The end of the tubing 140 is received
within a suitable bore in the hub 130 and the bore communicates
with the interior passage of the hollow needle 64 so that fluid
communication is established between the needle 64 and the tubing
The tubing 140 extends upwardly from the hub flange 132 and is
received within the groove 116 of the transverse wall 108 above
the horizontal groove 110. The tubing 140 extends to the top of
the plunger pieces 66 and 68. The tubing 140 is positioned around
the curved guide wall 94 and in a cooperating pair of the notches
98 (FIG. 6) defined in the walls 96. The tubing 140 extends out
of the plunger through the notches 99 (FIG. 5).
The distal end of the tubing 140 is connected in a well-known manner
to a luer lock connector fitting 148 or directly without fittings
into a fluid administration set connected to a patient. The fitting
148 can be connected to a suitable conventional or special tubing
system (not shown) which terminates in a needle or canula for insertion
into the patient.
In an alternate embodiment (not illustrated) the tubing 140 could
be rigid within the plunger 60 and could terminate at a lateral
port near the top of the plunger 60. Flexible tubing could then
be connected exterior of the plunger 60 to such a lateral port,
and the flexible tubing would then extend down toward the patient.
When the two plunger pieces 66 and 68 are secured together about
the needle 64 hub 130 and tubing 140 the hub and needle are securely
retained within the plunger 60. Typically, the plunger 60 with
the needle mounted therein, and projecting therefrom, is provided
to the user with a suitable protective sleeve (not shown) over the
projecting distal end of the needle 64. When it is desired to administer
the liquid agent from the vial 10 with the assembled plunger 60
and needle 64 in a conventional syringe pump, the protective sleeve
(not shown) is removed from the needle.
Next, the cap 16 is removed from the vial 10. The plunger and needle
assembly is then pushed onto the top of the vial container 12. The
outside diameter of the plunger 60 is less than the inside diameter
of the vial container 12 but the inside diameter defined by the
plunger pieces 66 and 68 is just large enough to receive the upwardly
projecting post 36 of the vial stopper 14.
Preferably, the plunger ribs 124 (FIG. 6) deform the resilient
material of the stopper post 36 slightly and establish a friction
engagement therewith. As the needle 64 is pushed into the stopper
14 the needle 64 pierces the stopper and completely penetrates
As illustrated in FIG. 5 the stopper 14 in a conventional ABBOJECT.RTM.
brand vial, defines a concave cavity 156 facing downwardly toward
the container interior. The distal end of the needle 64 passes completely
through the stopper post 36 and enters the cavity within the stopper.
The end of the needle 64 is exposed to the container liquid agent.
The bottom ends of the plunger pieces 66 and 68 engage the larger
diameter stopper seal piston 30.
Initially, when the plunger and needle are first engaged as described
above with the stopper at the top of the container, the ribs 124
on the inside of the plunger pieces 66 and 68 provide sufficient
frictional engagement to permit further handling without the vial
and plunger being inadvertently pulled apart.
The assembly is installed in the conventional syringe pump with
the vial 10 in the location normally occupied by a hypodermic syringe
body. The flange 48 is engaged with the syringe pump stationery
structure (shown in phantom in FIG. 5 as elements 153). The bearing
plate 70 at the upper end of the plunger (FIG. 6) is adapted to
be engaged with the movable drive member or pusher plate of the
syringe pump (indicated schematically in FIG. 5 by arrow 154). The
syringe pump pusher plate is typically driven by a slowly rotating,
fine-threaded screw drive so as to move the plunger further inwardly
into the vial 10. Because the bottom of the plunger 60 is engaged
with the top of the vial stopper seal piston 30 movement of the
plunger 60 into the vial 10 necessarily slides the stopper 14 further
into the vial. This forces the liquid agent through the needle 64
and tubing 140 to the patient.
Conventional syringe pumps are typically hung in an elevated orientation
from a stand adjacent the patient's bed. The moving pusher plate
of the syringe pump is located vertically above the plunger, and
the plunger is located vertically above the vial 10. With the system
of the present invention, this type of orientation accommodates
the initial purging of air from the system while the plunger and
vial are mounted in the syringe pump. Specifically, before connecting
the tubing to the patient, the syringe pump can be started to force
the plunger into the vial. Because any air bubbles that may initially
be in the vial would be at the top of the vial, the air bubbles
pass into the needle and through the tubing. The air can be vented
out of the distal end of the tubing before connecting the tubing
to the patient. This is a relatively simple process and avoids the
more complex conventional techniques that must be employed when
a regular syringe is placed vertically in a syringe pump with a
needle projecting downwardly. With such a conventional syringe,
the syringe must first be manually held and oriented with the needle
pointing upwardly while the syringe plunger is manually pressed
slightly to purge the air before inverting the syringe and placing
it into the syringe pump.
In the present invention, because the vial stopper post 36 has
a relatively short length, and because the stopper includes a cavity
156 a relatively short needle can be employed. Typically, a short,
conventional needle may be used rather than a more expensive, longer
needle employed in some syringes. In the preferred form, the needle
64 is an 18 gauge needle.
In the preferred form, the tubing 140 is a microbore, polyvinyl
chloride tubing with a small internal diameter (approximately 0.050
The ABBOJECT.RTM. brand stopper is normally provided with a threaded
post 36. Thus, if desired, the plunger 60 of the present invention
may be modified to threadingly engage such a threaded post. To that
end, the ribs 124 of the plunger pieces 66 and 68 (FIG. 6) may be
replaced with a suitable thread form. With such a construction,
the plunger could be pulled in certain optional procedures to establish
a suction effect within the vial.
It will be appreciated that the flange 48 which is added to the
vial 10 may be located at any appropriate location along the length
of the vial, depending upon the structure and size of the syringe
pump to be used. However, a number of the newer, conventional syringe
pumps typically employ a standard arrangement so that the vial 10
can be provided with the flange 46 at a particular location that
will function in a variety of syringe pumps.
It will be appreciated that the capability of the system of the
present invention to use glass vials eliminates a intermediate step
employed in some conventional procedures wherein the liquid agent
is transferred from a glass vial (as provided by the liquid agent
supplier) to a plastic syringe. The use of a glass vial is advantageous
with those types of liquid agents that are only stable over a long
shelf life term in glass (as opposed to thermoplastic containers).
However, the plunger system of the present invention may also be
employed with a variety of vials, including plastic vials.
It will also be appreciated that the present invention system may
be employed with vials having only a single open end and single
stopper (as illustrated). This eliminates having to use vials with
two open ends and two stoppers. The present invention thus provides
a more simple and economical design.
It will be readily apparent from the foregoing detailed description
of the invention and from the illustrations thereof that numerous
variations and modifications may be effected without departing from
the true spirit and scope of the novel concepts or principles of