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Description  |
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FIELD OF THE INVENTION
The present invention relates generally to control devices for fluid
dispensing machines. In particular, the present invention relates to a
pneumatic controller for producing a variable control signal to control
fluid dispersement to a patient from an angiographic system.
BACKGROUND OF THE INVENTION
Angiography is a procedure used in the detection and treatment of
abnormalities or restrictions in blood vessels. During angiography, a
radiographic image of a vascular structure is obtained by injecting
radiographic contrast material through a catheter into a vein or artery.
The vascular structures fluidly connected with the vein or artery in which
the injection occurred are filled with contrast material. X-rays are
passed through the region of the body in which the contrast material was
injected. The X-rays are absorbed by the contrast material, causing a
radiographic outline or image of the blood vessel containing the contrast
material. The X-ray's images of the blood vessels filled with the contrast
material are usually recorded onto film or video tape and are displayed on
a fluoroscope monitor.
During angiography, after a physician places a catheter into a vein or
artery, the angiographic catheter is connected to either a manual or an
automatic contrast injection mechanism. A typical manual contrast
injection mechanism includes a syringe and a catheter connection. The user
of the manual contrast injection mechanism adjusts the rate and volume of
injection by altering the manual actuation force applied to the plunger of
the syringe.
Automatic contrast injection mechanisms typically involve a syringe
connected to a linear actuator. The linear actuator is connected to a
motor, which is controlled electronically. The operator enters into the
electronic control a fixed volume of contrast material and a fixed rate of
injection. There is no interactive control between the operator and the
machine, except to start or stop the injection. A change in flow rate
occurs by stopping the machine and resetting the parameters.
Improvements to controlling an injection mechanism are desirable.
SUMMARY OF THE INVENTION
The present invention is directed to a controlled device to control a fluid
supply machine that substantially obviates one or more of the problems due
to limitations and disadvantages of the prior art.
To achieve the advantages of the invention and in accordance with the
purposes of the invention, as embodied and broadly described herein, the
invention comprises a control device for controlling a fluid supply
machine. The device includes a housing, a pressure control member secured
to the housing, a first fluid-conduit member, and a first sensor. The
pressure control member is constructed and arranged to selectively change
a fluid pressure within the control member. The first fluid-conduit member
is in fluid-flow communication with the pressure control member. The first
sensor is in fluid-flow communication with the first fluid-conduit member.
The sensor is constructed and arranged to generate a control signal based
upon the fluid pressure within the control member.
Preferably, the housing comprises an inexpensive, light weight material. In
some preferred applications, the housing is plastic. This permits the
housing to be disposable. That is, after using on one patient, the entire
housing may be discarded.
Preferably, the housing defines a wall enclosing a housing interior. The
pressure control member is positioned within the housing interior.
In some systems, the pressure control member includes a first air bladder
oriented within the housing interior and comprising a resilient material.
The first air bladder has a volume selectively adjustable to change the
fluid pressure within the first air bladder.
In some preferred embodiments, the housing wall defines a first aperture to
provide access to the first air bladder. Preferably, a portion of the
first air bladder extends through the first aperture, such that it may be
controlled by a user.
In one preferred embodiment, the control device includes a second air
bladder oriented within the housing interior. The second air bladder has a
volume selectively adjustable to change a fluid pressure within the second
air bladder. A second fluid-conduit member is in fluid-flow communication
with the second air bladder, and a second sensor is in fluid-flow
communication with the second fluid-conduit member. The sensor is
constructed and arranged to generate a control signal based upon the
second air bladder fluid pressure. In some preferred systems, the second
air bladder controls dispersement of a saline fluid to a patient.
In one preferred system, the housing defines a second aperture. Preferably,
a portion of the second air bladder extends through the second aperture.
In one embodiment, the housing first aperture and second aperture are in a
same plane. In another embodiment, the housing first aperture and second
aperture are in a pair of parallel planes. In yet another embodiment, the
housing first aperture is in a first plane, the housing second aperture is
in a second plane; and the first and second planes intersect at an oblique
angle. In another embodiment, the housing first aperture is in a first
plane, the housing second aperture i:s in a second plane; and, the second
plane is normal to the first plane.
Preferably, the housing defines at least one groove constructed and
arranged to snap on to tubing. In certain preferred arrangements, there is
a pair of grooves intersecting normal relative to one another. This allows
the control device housing to be snap fitted on to any one of a number of
tubes in a typical angiographic system.
In certain preferred arrangements, the first air bladder defines a first
spherical portion and a first planar portion. The first spherical portion
projects through the first aperture in the housing, and the first planar
portion is oriented completely within the housing interior. Preferably, in
certain embodiments, the second air bladder defines a second spherical
portion and a second planar portion. The second planar portion preferably
extends through the second aperture, and the second spherical portion is
oriented completely within the housing interior. This preferred
arrangement provides a different tactical sensation or feel between the
first and second air bladders.
In certain preferred embodiments, the first fluid conduit member includes a
first flexible lumen, and the second fluid conduit member includes a
second flexible lumen. In some preferred embodiments, the first lumen and
the second lumen each comprises a plastic tube.
Preferably, the housing is sized to comfortably fit within a user's hand.
Preferably, the housing includes a length of no more than about five
inches, and a width of no more than about two inches.
In another aspect, the invention is directed to a method for controlling a
fluid-supply machine for dispensing fluid into a patient. The method
comprises a step of securing a pressure-control member to a fluid-supply
machine. A pressure is changed within the pressure-control member by
adjusting a volume of the pressure-control member. A fluid is dispensed
into a patient, based upon the pressure within the pressure-control
member. The steps of changing and dispensing are selectively repeated,
until the desired procedure on the patient is completed.
Preferably, after the step of selectively repeating, the pressure control
member is removed from the fluid-supply machine. The pressure-control
member is then discarded. A new, different, second pressure-control member
is then secured to the fluid-supply machine, for operation on a different,
second patient.
In one preferred method, the step of securing includes attaching a
handpiece which houses the pressure control member. The pressure control
member preferably includes a resilient bulb. Preferably, the step of
changing includes applying pressure to the bulb. This decreases the volume
within the bulb and changes the pressure internal to the bulb.
It is to be understood that both the foregoing general description and the
following detailed description are exemplary and explanatory only and are
not restrictive of the invention, as claimed.
The accompanying drawings, which are incorporated in and constitute a part
of this specification, illustrate example embodiments of the invention and
together with the description, serve to explain the principals of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a first embodiment of a controller, embodying
principles of the present invention;
FIG. 2 is a side elevational view of the controller depicted in FIG. 1,
embodying principles of the present invention;
FIG. 3 is a cross-sectional view of the section taken along the line 3--3,
shown in FIG. 2;
FIG. 4 is a bottom plan view of the controller depicted in FIG. 1;
FIG. 5 is a top plan view of a second embodiment of a controller, embodying
principles of the present invention;
FIG. 6 is a side elevational view of the controller depicted in FIG. 5;
FIG. 7 is top plan view of a third embodiment of a controller, embodying
principles of the present invention;
FIG. 8 is a side elevational view of the controller depicted in FIG. 7;
FIG. 9 is a top plan view of a fourth embodiment of a controller, embodying
principles of the present invention;
FIG. 10 is a side elevational view of the controller depicted in FIG. 8;
FIG. 11 is a top plan view of a fifth embodiment of a controller, embodying
principles of the present invention; and
FIG. 12 is a schematic drawing illustrating control aspects of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
U.S. Pat. No. 5,573,515 to Wilson et al., and commonly assigned as the
disclosure herein, describes, among other things, an angiographic
injection system which permits the user to control the rate of
dispersement of the angiographic fluid through a remote control. The
present invention is a pneumatic controller which is usable with the
system described in the Wilson et al. patent. Specifically, the present
invention produces a variable control signal between a preset maximum
value and a minimum value, proportional to the change in air pressure
within an air bladder to control the angiographic syringe.
FIGS. 1-4 depict a first embodiment of a control device of the present
invention. In FIGS. 1 and 2, a control device is shown generally at 20.
Control device 20 includes generally a handpiece or shell or housing 22
which holds and has secured therein at least a single pressure control
member 24. The pressure control member is constructed and arranged to
selectively change a fluid pressure within the control member, based upon
adjustment by a user. In the particular embodiment illustrated in FIGS. 1
and 2, housing 22 holds a second pressure control member 26. Second
pressure control member 26 operates analogously to pressure control member
24.
In FIG. 3, a fluid conduit member 28 is in fluid flow, e.g. air-flow or
liquid-flow, communication with the pressure control member 24. A fluid
pathway 30, FIG. 2, connects the pressure control member 24 to the first
fluid conduit member 28. The first fluid conduit member 28 provides a
fluid pathway and airflow communication between the pressure control
member 24 and first sensor 32 (FIG. 12). First sensor 32 is constructed
and arranged to generate a control signal based upon the fluid pressure
within the control member 24. That is, first sensor 32 senses a pressure
differential between atmospheric pressure and the pressure within the
pressure control member 24. Based upon the size of the pressure
differential, the first sensor 32 generates a control signal proportional
to this size. The control signal regulates the rate of flow of the fluid
being dispensed from the angiographic system.
Analogous to pressure control member 2.4, the second pressure control
member 26 is connected to a fluid pathway 34, FIG. 2, which provides a
fluid flow (air-flow or liquid-flow) communication between the second
pressure control member 26 and a second fluid conduit member 36 (FIG. 3).
Second fluid conduit member 36 leads to a second sensor 38 (FIG. 12).
Second sensor 38 senses a pressure differential between the atmosphere and
the pressure within second pressure control member 26, and generates a
signal based upon this. Preferably, the second sensor 38 sends a signal to
control dispensement of a second fluid within the angiographic system,
such as saline.
With the overall principles of operation in mind, we now turn to more
specific details of the preferred embodiments.
Housing 22 is provided to hold and contain the pressure control members 24,
26, and prevent the pressure control members 24, 26 from involuntary or
unintentional activation. In certain preferred embodiments, housing 22 is
constructed of a light weight, durable material. In the preferred
embodiment illustrated, housing 22 is constructed of plastic, i.e., top
and bottom injection molded halves (for example, a clamshell type
construction). The plastic material is inexpensive, in order to permit
single use disposability. That is, after the control device 20 is used
once on one patient, the entire control device 20 is discarded and not
reused. In other embodiments, housing 22 is constructed of cardboard or
Styrofoam.
Housing 22 includes a wall 40. Wall 40 encloses a housing interior 42. The
first and second pressure control members 24, 26 are positioned and
oriented within housing interior 42. In this way, housing 22 helps to
protect first and second pressure control members 24, 26 from accidental
or unintentional activation.
Wall 40 defines at least a first aperture 44. First aperture 44 provides a
window or access port into housing interior 42. Wall 40 may also, in
certain embodiments, define a second aperture 46. Second aperture 46 is
analogous to first aperture 44, and provides communication between housing
interior 42 and the environment external to housing 22.
In the particular embodiment illustrated in FIGS. 1 and 2, first and second
apertures 44, 46 are defined in a single plane. That is, the plane which
contains the first aperture 44 is coterminous with the plane which
contains second aperture 46.
Preferably, control device 20 is sized to easily fit within and be
controlled by a person's hand. In the preferred embodiment illustrated in
FIGS. 1 and 2, housing 22 is texturized to aid in gripping, especially for
use if the user is wearing a latex surgical glove. The texturization
includes Mold Tech 11010, available from Mold Tech of Villa Park, Ill.
Housing 22 is constructed such that it can withstand a force of at least
about 20 pounds when squeezed by a person's hand. As shown in FIG. 2,
housing 22 is contoured, such that it does not pinch or puncture surgical
gloves during use.
In the embodiment illustrated in FIGS. 1 and 2, housing 22 is usable by
either a person's right hand or left hand. It is sized to fit and be
controlled comfortably within a majority of the population's hand.
Specifically, housing 22 has a length of no more than about five inches,
preferably 3.5-4.5 inches, and more preferably about 3.8 inches. Housing
22 has a width of no more than about two inches, and preferably about 1
inch. The depth of housing 22 is from about 0.5-1.5 inches, and preferably
about 1 inch.
Still referring to FIGS. 1 and 2, as described above, pressure control
member 24 acts to selectively change a fluid pressure within control
member 24. Based upon the change in pressure within control member 24,
first sensor 32 sends a signal to the angiographic system to control the
rate of fluid, e.g., contrast media, dispensed into the patient. While a
variety of embodiments are contemplated, in the particular embodiment
illustrated, pressure control member 24 includes a squeeze bulb, or air
filled cavity or bag, or air bladder 48.
First air bladder 48 is constructed of a resilient material, such that it
retains its shape, but defines a volume which is selectively adjustable.
That is, a user applies force to the external surface of wall 50 of air
bladder 48. Responsive to the external force applied on wall 50, the wall
50 moves inwardly toward itself, and the volume within air bladder 48
decreases. As the volume within air bladder 48 decreases, the pressure
changes, i.e., it increases. The air pressure is conveyed through fluid
pathway 30 and first fluid conduit member 28 to first sensor 32. First
sensor 32 detects the pressure differential between the pressure within
air bladder 48 and atmospheric pressure. Based upon this pressure
differential, sensor 32 sends a signal to the angiographic system to
control the flow of contrast media.
Upon release of the external force from wall 50, air bladder 48 resumes its
original shape. It is ready to be manipulated again by the user.
Preferably, air bladder 48 is constructed from a flexible material, yet one
which is able to retain its original shape. Suitable materials include
plastic, latex rubber, or elastomeric material. Air bladder 48 is
constructed such that the maximum air pressure created when squeezing air
bladder 48 does not exceed the pressure which can be accurately and safely
handled by sensors 32, 36. In one preferred embodiment, sensors 32, 36 can
accurately handle a maximum pressure of about 30 psi. If alternate sensors
are used instead of sensors 32, 36, the maximum air pressure can be
changed, based upon the particular sensors used.
Second pressure control member 26 is analogous to pressure control member
24. Specifically, second pressure control member 26, in the particular
embodiment illustrated, includes a fluid filled cavity or bag, or squeeze
bulb, or air bladder 52. Second air bladder 52 includes a wall 54
responsive to an external force. Wall 54 is constructed of a resilient
material, such that it is responsive to external forces and will move
internally to adjust and change the internal volume of the second air
bladder 52.
As with first air bladder 48, second air bladder 52 has a volume
selectively adjustable to change the fluid pressure, e.g. air pressure,
within the second air bladder 52. When an external force is applied to
wall 54, the volume of second air bladder 52 decreases, which increases
the pressure. This pressure is conveyed through fluid pathway 34, through
second fluid-conduit member 36, and to second sensor 38. Second sensor 38
detects the pressure differential between the pressure within second air
bladder 52 and the atmosphere. Although second sensor 38 could operate
analogously to first sensor 32 and generate a signal proportional to the
pressure differential, second sensor 38 is constructed and arranged to
operate as a switch, i.e. a digital-type device. When the pressure
differential exceeds a certain amount, second sensor 38 sends a signal to
the angiographic system which dispenses a second fluid into the patient,
such as saline. In other words, when second air bladder 52 is squeezed or
depressed a certain amount, e.g., 50% of the total volume of second air
bladder 52, it provides a saline flush into the patient.
First and second air bladders 48 and 52 are each constructed to resemble a
truncated sphere. That is, first air bladder 48 defines a first spherical
portion 56 and a first planar portion 58. Analogously, second air bladder
52 defines a second spherical portion 60 and a second planar portion 62.
In profile, as shown in FIG. 2, the first and second air bladders 48, 52
are generally D-shaped. As described in more detail below, this shape is
useful for providing the user with information about which air bladder he
is manipulating.
As shown in FIGS. 1 and 2, first air bladder 48 includes a portion which
extends through the first aperture 44 of the wall 40. Second air bladder
52 includes a portion which extends through the second aperture 46 of the
wall 40. In the particular embodiment illustrated, the first and second
air bladders, 48, 52 are oriented such that different ones of their
surfaces are projecting through their respective apertures. This provides
the user with a different external feel and provides him information as to
which button he is manipulating, without having to look at the control
device 20. In particular, the first spherical portion 56 of the first air
bladder 48 projects through the first aperture 44, while the first planar
portion 58 is oriented completely within the housing interior 42. The
second planar portion 62 of the second air bladder 52 extends and projects
through the second aperture 46, while the second spherical portion of the
second air bladder 52 is oriented completely within the housing interior
42. Because of the different contour between the first spherical portion
56 and the second planar portion 62, the user will be able to
differentiate between the first and second air bladders 48 and 52.
In reference now to FIG. 2, the first and second fluid pathways 30, 34 are
illustrated connecting the first and second air bladders 48, 52 to the
first and second fluid conduit members 20, 36. In particular, fluid
pathway 30 may include a variety of embodiments, e.g. paratubing, plastic
luer fittings, plastic hollow tubing, two discrete tubes bonded together,
bi-lumen, tri-lumen, multiple-lumen, etc. In the particular illustrated,
fluid pathway 30 is a plastic, hollow tube. Analogously, fluid pathway 34
is a plastic hollow tube.
In reference now to FIGS. 2 and 3, first and second fluid conduit members
28, 36 provide a fluid flow pathway from the fluid pathways 30, 34,
respectively. In the particular embodiment illustrated, first fluid
conduit member 28 includes a single lumen tubing 70. Second fluid conduit
member 36 also includes a single lumen tubing 72. Tubings 70, 72 are held
by a single, outer tubing or umbilical tubing 74. Umbilical tubing 74 is
flexible, although semirigid, to prevent kinking and blockage of airflow
through each lumen 70, 72. . Preferably, the conduit members 28, 36 have
sufficient flexibility for ease and comfort of use, yet minimum compliance
for better transfer of air pressure. In one preferred arrangement,
umbilical tubing 74 withstands a crushing force of about 20 psi without
collapsing either of the lumens 70, 72.
In an alternate embodiment, first and second fluid conduit members 28, 36
are rigid channels, columns, or tubes.
Preferably, umbilical tubing 74 is long enough to provide the user with
flexibility and movement during angiographic procedures. In the embodiment
illustrated in FIG. 2, umbilical tubing 74 is about six feet in length.
In reference now to FIG. 2, umbilical tubing 74 is provided with connectors
to connect the lumens 70, 72 to the appropriate air line, and sensor.
While a variety of embodiments are contemplated, the FIG. 2 embodiment
shows plastic bore fittings or connectors 76, 78. Preferably, connectors
76 and 78 are opposite to each other, such that the user will not be able
to mix up the connections. That is, a male luer fitting connects the
control line from the first air bladder (which controls the flow of
contrast media) to its respective first sensor 32, while a female luer
fitting connects the control line from the second air bladder 52 (which
controls saline dispensement).
In accordance with the invention, control device 20 may be conveniently
stored or oriented in a position with the angiographic system, when not in
immediate use. In reference to FIG. 4, control device 20 includes
structure which permits control device 20 to be received, hooked by, or
snapped into reciprocal structure. The FIG. 4 embodiment shows at least
one channel, trench, or groove 80 constructed and arranged to snap on to
reciprocal, mating structure, such as tubing. A second groove 82
intersects and is normal to first groove 80. Grooves 80, 82 are defined by
and embedded within wall 40 of housing 22. Grooves 80, 82 allow housing 22
to be hooked on or snapped into place in a diverse number of orientations
on a number of different tubes in the angiographic system.
As can be appreciated from the foregoing description, at least because, in
certain preferred embodiments, control device 20 consists essentially of
only housing 22; first and second air bladder 48, 52; first and second
fluid pathways 30, 34; and tubing 70, 72, 74, the device 20 is readily
disposable. That is, for example, control device 20 is inexpensive to
manufacture, and due to the lack of significant extra or expensive
components, or electronic components, can be disposed of after using on
only one patient. For example, the handpiece lacks any active sensors and
magnets. This contributes to cleaner, more sterile, and healthy
conditions.
In reference now to FIGS. 5-6, a second embodiment of a control device 90
is illustrated. Control device 90 includes a handpiece or housing 92
having a wall 93. Wall 93 defines first and second apertures 95, 96. In
this embodiment, apertures 95, 96 are oriented in two different planes,
generally parallel relative to each other, FIG. 6. In addition, as shown
in FIG. 5, apertures 95, 96 are non-axially aligned. That is, the center
of aperture 95 does not align linearly with the center of aperture 96. A
central axis passing through the center of aperture 95 is parallel to a
control axis passing through the center of aperture 96.
Control device 90 includes first and second air bladders 98, 99. Air
bladders 98, 99 are in fluid flow communication with airflow conduits 100,
101, which lead to sensors, such as those illustrated in FIG. 12.
Control device 90 operates analogously to co | | |
