U.S. patent application number 15/804577 was filed with the patent office on 2018-03-08 for high pressure sensor for use with a fluid delivery system.
The applicant listed for this patent is BAYER HEALTHCARE LLC. Invention is credited to GERALD W. CALLAN, MICHAEL A. RILEY, MICHAEL A. SPOHN, MICHAEL J. SWANTNER.
Application Number | 20180064866 15/804577 |
Document ID | / |
Family ID | 49233086 |
Filed Date | 2018-03-08 |
United States Patent
Application |
20180064866 |
Kind Code |
A1 |
RILEY; MICHAEL A. ; et
al. |
March 8, 2018 |
HIGH PRESSURE SENSOR FOR USE WITH A FLUID DELIVERY SYSTEM
Abstract
A pressure sensor for use with a fluid delivery system having
good sensitivity at low pressure, but also configured to remain in
operating condition after being exposed to high pressures is
disclosed herein. In one variation, the pressure sensor includes a
fluid path set, a deformable element associated with the fluid path
set and configured to deform in response to an external pressure,
and a pressure transducer for monitoring deformation of the
deformable element. In certain embodiments, the pressure sensor is
configured to measure fluid pressure within the range of between
about 0 mm Hg to about 300 mm Hg. However, the sensor pressure is
also be configured to remain functional after being exposed to
pressure in excess of about 60,000 mm Hg.
Inventors: |
RILEY; MICHAEL A.;
(SAXONBURG, PA) ; CALLAN; GERALD W.; (CRANBERRY
TWP, PA) ; SPOHN; MICHAEL A.; (FENELTON, PA) ;
SWANTNER; MICHAEL J.; (SAXONBURG, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BAYER HEALTHCARE LLC |
Whippany |
NJ |
US |
|
|
Family ID: |
49233086 |
Appl. No.: |
15/804577 |
Filed: |
November 6, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15342434 |
Nov 3, 2016 |
9808571 |
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15804577 |
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13798709 |
Mar 13, 2013 |
9486579 |
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15342434 |
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61619600 |
Apr 3, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01L 11/025 20130101;
A61M 2230/30 20130101; A61M 5/007 20130101; A61M 2205/18 20130101;
G01L 19/0618 20130101; A61M 2205/581 20130101; A61M 39/22 20130101;
A61M 2039/229 20130101; A61M 2205/583 20130101; A61M 2205/3355
20130101; A61M 2205/587 20130101; A61M 2205/3306 20130101; A61M
5/1723 20130101; A61M 2205/3337 20130101; A61M 5/16854
20130101 |
International
Class: |
A61M 5/00 20060101
A61M005/00; A61M 5/172 20060101 A61M005/172; A61M 39/22 20060101
A61M039/22; G01L 11/02 20060101 G01L011/02; G01L 19/06 20060101
G01L019/06; A61M 5/168 20060101 A61M005/168 |
Claims
1. A fluid path set for a fluid delivery system comprising: a
manifold comprising a plurality of fluid control valves in series
fluid communication, wherein the first fluid control valve
comprises a first port, a second port, and a third port, wherein
the second port of the first fluid control valve is in fluid
connection with a first port of a second fluid control valve and
wherein a second port of the second fluid control valve is in fluid
connection with a catheter connector conduit; a connector for
providing fluid connection between a low pressure hand-operated
syringe and the first port of the first fluid control valve; a
tubing for providing fluid connection between a high pressure
syringe and the third port of the first fluid control valve; and a
pressure sensor in continuous fluid communication with fluid in a
tubing portion in the catheter connector conduit and adapted to
measure fluid pressure in the tubing portion, the pressure sensor
comprising a deformable element configured to deform in response to
changing fluid pressure in the tubing portion, and wherein the
pressure sensor converts to an electronic signal a representation
of the amount of deformation of the deformable element to measure
the changing fluid pressure in the tubing portion.
2. The fluid path set of claim 1, wherein the pressure sensor is
configured to measure pressure within the range of between about 0
mm Hg to about 300 mm Hg and wherein the pressure sensor is a high
pressure sensor configured such that it remains in working
condition after being exposed to pressure in excess of about 60,000
mm Hg.
3. The fluid path set of claim 1, further comprising a pressure
transducer disposed within the tubing portion of the catheter
connector conduit.
4. The fluid path set of claim 3, wherein the pressure sensor
comprises or is connected to an external signal detector or monitor
connected with the pressure transducer.
5. The fluid path set of claim 4, wherein the external signal
detector or monitor is in wired or wireless connection with the
pressure transducer.
6. The fluid path set of claim 4, wherein the external detector or
monitor is configured to process and analyze hemodynamic signals
measured by the pressure transducer.
7. The fluid path set of claim 4, wherein the external detector or
monitor collects and relays hemodynamic signals measured by the
pressure transducer to a control unit.
8. The fluid path set of claim 7, wherein the control unit is
configured to display or analyze data recorded by the pressure
sensor.
9. The fluid path set of claim 1, further comprising the low
pressure hand-operated syringe in fluid connection with the first
port of the first fluid control valve.
10. The fluid path set of claim 9, further comprising a high
pressure syringe in fluid connection with the third port of the
first fluid control valve through the tubing.
11. The fluid path set of claim 1, further comprising a fluid
source in fluid connection with a third port of the second fluid
control valve.
12. The fluid path set of claim 1, wherein each of the first and
second fluid control valves comprises a multi-position stopcock
valve.
13. The fluid path set of claim 1, wherein the manifold further
comprises a manifold housing, and each of the first and second
fluid control valves are in friction-fit connection within the
manifold housing.
14. The fluid path set of claim 1, wherein the manifold comprises
an L-shaped manifold housing comprising a longitudinal portion and
a lateral portion, and wherein the third port of the first fluid
control valve is generally coaxial with the lateral portion.
15. The fluid path set of claim 1, wherein the manifold further
comprises a manifold housing, the manifold housing comprising a
stop element to prevent rotation of the first fluid control valve
to a position that opens a fluid path between the third port and
the first port of the first fluid control valve.
16. A fluid delivery system, comprising: a power injector adapted
to interface with and actuate a high pressure syringe; a low
pressure hand-operated syringe; a manifold comprising a plurality
of fluid control valves in series fluid communication, wherein the
first fluid control valve comprises a first port, a second port,
and a third port, wherein the second port of the first fluid
control valve is in fluid connection with a first port of a second
fluid control valve and wherein a second port of the second fluid
control valve is in fluid connection with a catheter connector
conduit; a connector providing fluid connection between the low
pressure hand-operated syringe and the first port of the first
fluid control valve; a tubing providing fluid connection between
the high pressure syringe and the third port of the first fluid
control valve; and a pressure sensor in continuous fluid
communication with fluid in a tubing portion in the catheter
connector conduit and adapted to measure fluid pressure in the
tubing portion, the pressure sensor comprising a deformable element
configured to deform in response to changing fluid pressure in the
tubing portion, and wherein the pressure sensor converts to an
electronic signal a representation of the amount of deformation of
the deformable element to measure the changing fluid pressure in
the tubing portion.
17. The fluid delivery system of claim 16, wherein the pressure
sensor is configured to measure pressure within the range of
between about 0 mm Hg to about 300 mm Hg and wherein the pressure
sensor is configured such that it remains in working condition
after being exposed to pressure in excess of about 60,000 mm
Hg.
18. The fluid delivery system of claim 16, further comprising a
pressure transducer disposed within the tubing portion of the
catheter connector conduit.
19. The fluid delivery system of claim 18, wherein the pressure
sensor comprises or is connected to an external signal detector or
monitor connected with the pressure transducer.
20. The fluid delivery system of claim 19, wherein the external
signal detector or monitor is in wired or wireless connection with
the pressure transducer and is configured to process and analyze
hemodynamic signals measured by the pressure transducer.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser.
No. 13/798,709, filed Mar. 13, 2013, which claims the benefit of
U.S. Provisional Application No. 61/619,600, filed Apr. 3, 2012,
entitled "High Pressure Transducer", which is hereby incorporated
by reference in its entirety.
BACKGROUND
Field of the Technology
[0002] The disclosure relates generally to medical fluid delivery
applications and, particularly, to a fluid delivery system
including a high pressure sensor for measuring intravascular
pressure of a patient during medical fluid delivery
applications.
Description of Related Art
[0003] In many medical diagnostic and therapeutic procedures, a
medical practitioner, such as a physician, injects a patient with a
fluid. In recent years, a number of injector-actuated syringes and
powered fluid injectors for pressurized injection of fluids, such
as contrast media (often referred to simply as "contrast"), have
been developed for use in procedures such as angiography, computed
tomography, ultrasound, and NMR/MRI. In general, these powered
fluid injectors are designed to deliver a preset amount of contrast
at a preset flow rate.
[0004] Angiography is used in the detection and treatment of
abnormalities or restrictions in blood vessels. In an angiographic
procedure, a radiographic image of a vascular structure is obtained
through the use of a radiographic contrast that is injected through
a catheter. The vascular structures in fluid connection with the
vein or artery in which the contrast is injected are filled with
contrast. X-rays passing through the region of interest are
absorbed by the contrast, causing a radiographic outline or image
of blood vessels containing the contrast. The resulting images can
be displayed on, for example, a video monitor and recorded.
[0005] In a typical angiographic procedure, the medical
practitioner places a cardiac catheter into a vein or artery. The
catheter is connected to either a manual or an automatic contrast
injection mechanism. A typical manual contrast injection mechanism
includes a syringe in fluid connection with a catheter connection.
The fluid path also includes, for example, a source of contrast, a
source of flushing fluid, typically saline, and a pressure
transducer to measure patient blood pressure. In a typical system,
the source of contrast is connected to the fluid path via a valve,
for example, a three-way stopcock. The source of saline and the
pressure transducer may also be connected to the fluid path via
additional valves, again, such as stopcocks. The operator of the
manual contrast injection mechanism controls the syringe and each
of the valves to draw saline or contrast into the syringe and to
inject the contrast or saline into the patient through the catheter
connection. The operator of the syringe may adjust the flow rate
and volume of injection by altering the force applied to the
plunger of the syringe. Thus, manual sources of fluid pressure and
flow used in medical applications, such as syringes and manifolds,
typically require operator effort that provides feedback of the
fluid pressure/flow generated to the operator. The feedback is
desirable, but the operator effort often leads to fatigue. Thus,
fluid pressure and flow may vary depending on the operator's
strength and technique.
[0006] Automatic contrast injection mechanisms typically include a
syringe connected to a powered fluid injector having, for example,
a powered linear actuator. Typically, an operator enters settings
into an electronic control system of the powered fluid injector for
a fixed volume of contrast and a fixed rate of injection. In many
systems, there is no interactive control between the operator and
the powered fluid injector, except to start or stop the injection.
A change in flow rate in such systems occurs by stopping the
machine and resetting the injection parameters. Automation of
angiographic procedures using powered fluid injectors is discussed,
for example, in U.S. Pat. Nos. 5,460,609; 5,573,515; and
5,800,397.
[0007] The pressure transducer in the above-discussed modalities is
used to provide a hemodynamic waveform, referred to as
intra-coronary blood pressure, of a patient during clinical
procedures. Cardiologists often refer to hemodynamic waveforms
since they essentially provide real time measurement of blood
pressure, which correlates to the performance of the heart.
However, these pressure transducers are extremely sensitive to even
moderate pressures generated during activation of the syringe, and
many pressure transducers can be damaged if they are subjected to
pressures as low as about 75 psi. Hand-held syringes can generate
pressures of 200 psi or more. Power injectors may pressurize the
contents of a syringe to pressure exceeding 1200 psi (about 63,000
mm Hg), far beyond the maximum pressure of the pressure
transducer.
[0008] In view of these high pressure levels in existing fluid
delivery systems, the systems include a means, such as a valve, for
isolating the pressure transducer from the pressurized fluid in
order to avoid damaging the pressure transducer during injection.
While the syringe is not activated, the valve is open so that the
pressure transducer can monitor blood pressure. In one known
arrangement, the pressure transducer and contrast injection
mechanism are connected to the catheter through a manifold. The
manifold includes a manually operated valve that enables the
injector operator to isolate the pressure transducer during the
injection of the contrast solution. This valve, typically a
stopcock, is used to isolate the pressure transducer to prevent
damage thereto. Specifically, a stopcock configuration is provided
which either allows the pressure transducer to be in fluid
communication with the catheter or the injection mechanism to be in
fluid communication with the catheter, but not both. Typically, the
stopcock handle must be turned manually to switch between the two
positions. Accordingly, this configuration provided by some
currently available manifolds does not allow, for example, contrast
injections to be made while the pressure transducer is in
communication with the catheter.
[0009] Another pressure isolation valve used for pressure
transducer protection purposes is disclosed by U.S. Patent
Application Publication No. 2006/0180202 to Wilson, et al. This
publication discloses an elastomeric valve having a valve body with
three ports including a contrast inlet port, a saline inlet and
pressure transducer port, and a patient or outlet port. The valve
body houses a disc holder and a valve disc therein. The valve disc
is formed from a molded elastomer, such as silicone rubber, with a
slit in the center. The elastomeric disc is sandwiched between the
valve body and disc holder and is affixed therebetween at the
perimeter of the disc. Such affixation may be effected by
entrapment, adhesion, mechanical, or chemical welding. The
elastomeric valve disclosed by this publication is responsive to
pressure changes in the valve that act on the elastomeric disc, and
the elastomeric disc is operative to protect a pressure transducer
connected to the pressure isolation port.
[0010] Fluid delivery systems having pressure isolation valves that
open and close automatically are also known in the art. For
example, U.S. Pat. No. 7,610,936 to Spohn, et al., incorporated
herein by reference, discloses a fluid delivery system having a
pressure isolation mechanism that includes a flow-activated valve
member adapted to selectively engage a seal seat to establish fluid
isolation between a fluid delivery system and a pressure
transducer. The flow-activated valve member is responsive to
increased fluid flow through a fluid path connected to the pressure
isolation mechanism and the valve member is operable to engage and
seal against an opposing seal seat. The valve member movement
effectively closes-off fluid flow to a port to which a pressure
transducer is connected, thereby isolating the pressure transducer
when high pressure fluid is injected through the fluid path.
[0011] However, despite the fact the above-described valves
effectively protect and isolate a pressure transducer when used
correctly, there are a number of drawbacks to such active pressure
isolation valve mechanisms. First, with manual isolation valves,
the user may forget to close the valve before activating the
associated syringe, and the pressurized fluid flow through the
system will likely damage the transducer. Additionally, if the
valve is not closed correctly, there is a risk that fluid drainage
would occur through the valve or port, during pressure transducer
zeroing. Furthermore, automatic or active pressure isolation valves
often rely on sealing, locking, or release mechanisms which tend to
be complex and, in some cases, prone to breaking or becoming stuck
in an open or closed position, or have a tendency to trap air.
[0012] Additionally, known pressure sensors must be positioned in a
separate port, typically a branch port, a secondary fluid path, or
line from the main fluid path of a fluid delivery system. While the
branch port or the secondary fluid path is selectively in fluid
communication with the main fluid path, the branch or delta between
the pressure sensor and the main fluid path reduces the accuracy
and reliability of pressure measurements. Furthermore, each branch
of a fluid system must be primed with a fluid, such as saline,
during use. In systems in which the pressure sensor is included in
a branch, port, or secondary fluid path, which is separate from the
main fluid path, a user must perform an extra flushing activity on
the branch, port, or secondary fluid path leading to the pressure
sensor, and these locations are prime locations for trapping air
bubbles. Performing an additional flushing activity increases the
difficulty and time required to perform a fluid injection.
BRIEF SUMMARY
[0013] Therefore, in view of the foregoing, there is a need for
applying a pressure sensor to a fluid injection system without the
need for active pressure isolation mechanisms. For example, it
would be beneficial if the pressure transducer of the pressure
sensor remained in continuous fluid communication with the fluid
path between the fluid delivery system and the patient, without the
risk that pressurized fluid would damage the pressure transducer.
However, the pressure transducer should also be capable of
measuring small changes in pressure to provide useful information
about intravascular blood pressure, particularly in the range of
about 0 mm Hg to about 300 mm Hg. It would also be beneficial if
the pressure transducer were configured to reduce fluid drainage
during zeroing and to simplify the process of priming the fluid
delivery system during use. The pressure transducer and fluid
delivery system detailed herein provide such beneficial
characteristics.
[0014] A pressure sensor for use with a fluid delivery system
having good sensitivity at low pressure but also configured to
remain in operating condition after being exposed to high pressures
is disclosed in detail herein. In one embodiment, a hemodynamic
pressure sensor for use with a fluid delivery system is disclosed,
comprising a fluid path defined by a tubing element, and a pressure
transducer in continuous fluid communication with fluid in the
tubing element and adapted to measure fluid pressure in the tubing
element. Fluid communication may mean direct contact with a fluid
medium or indirect, for example, across a membrane or other barrier
to permit the pressure transducer to ascertain fluid pressure
readings in the tubing element. The pressure transducer comprises a
deformable element configured to deform in response to changing
fluid pressure in the tubing element. The pressure transducer
converts to an electronic signal a representation of the amount of
deformation of the deformable element to measure the changing fluid
pressure in the tubing element.
[0015] The pressure transducer may be configured to measure
pressure within the range of between about 0 mm Hg to about 300 mm
Hg, and the pressure transducer may be configured such that it
remains in working condition after being exposed to pressure in
excess of about 60,000 mm Hg.
[0016] The pressure transducer may be configured to be placed in
fluid connection with a pressure port in fluid communication with
the tubing element.
[0017] The pressure transducer may be an optical pressure
transducer and the deformable element may be a flexible tube
enclosing the optical pressure transducer. The pressure transducer
may further comprise a radiation generator for promulgating a
radiation beam through the flexible tube and a detector for
detecting the promulgated radiation beam. The flexible tube may be
configured to deform in response to fluid pressure in the tubing
element, and the pressure transducer may be configured to measure
the deformation of the flexible tube.
[0018] The deformable element may be a diaphragm which flexes in
response to changing fluid pressure within the tubing element, and
the pressure transducer may measure flexing of the diaphragm and
convert to an electronic signal a representation of the amount of
flexing of the diaphragm to measure the changing fluid pressure in
the tubing element. A guard may be provided to selectively engage
and restrict movement of the diaphragm. The guard may engage the
diaphragm when fluid pressure in the tubing element exceeds a
possible human intra-coronary pressure range.
[0019] An external monitor may be in electronic communication with
the pressure transducer. The external monitor may comprise a signal
analysis processor for receiving the electronic signal from the
pressure transducer and be adapted to process the electronic signal
and transmit the electronic signal to a control unit.
[0020] A visual display may be provided on the external monitor for
displaying the electronic signal for a user. The visual display may
comprise a visual indicator comprising at least a warning indicator
which informs the user when measured fluid pressure is outside of a
possible human range of intracoronary pressure; a caution indicator
that informs the user when measured pressure is outside of a normal
human range for intracoronary pressure, but within the possible
human range; and a ready-for-use indicator that indicates that
measured fluid pressure is within the normal human range.
[0021] The pressure transducer may be connected to an external
monitor by one of a wired and wireless connection.
[0022] Another embodiment is directed to a fluid delivery system
comprising a first pressure fluid delivery device for delivering a
first injection fluid under pressure to a fluid path defined by a
tubing element, a second pressure fluid delivery device for
delivering a second injection fluid under pressure to the tubing
element and a pressure transducer in continuous fluid communication
with fluid in the tubing element and adapted to measure fluid
pressure in the tubing element. Fluid communication may mean direct
contact with a fluid medium or indirect, for example, across a
membrane or other barrier to permit the pressure transducer to
ascertain fluid pressure readings in the tubing element. The
pressure transducer comprises a deformable element configured to
deform in response to changing fluid pressure in the tubing
element. The pressure transducer converts to an electronic signal a
representation of the amount of deformation of the deformable
element to measure the changing fluid pressure in the tubing
element.
[0023] The fluid delivery system may further comprise a hand
manifold comprising a plurality of fluid control valves in series
fluid communication and connected to the fluid delivery devices and
to the tubing element. The fluid control valves selectively permit
fluid flow between the fluid delivery devices and the tubing
element.
[0024] The pressure transducer may be configured to be placed in
fluid connection with a pressure port in fluid communication with
the tubing element.
[0025] The pressure transducer may be an optical pressure
transducer and the deformable element may be a flexible tube
enclosing the optical pressure transducer. The pressure transducer
may further comprise a radiation generator for promulgating a
radiation beam through the flexible tube and a detector for
detecting the promulgated radiation beam. The flexible tube may be
configured to deform in response to fluid pressure in the tubing
element, and the pressure transducer may be configured to measure
the deformation of the flexible tube.
[0026] The deformable element may be a diaphragm which flexes in
response to changing fluid pressure within the tubing element, and
the pressure transducer may measure flexing of the diaphragm and
convert to an electronic signal a representation of the amount of
flexing of the diaphragm to measure the changing fluid pressure in
the tubing element. A guard may be provided to selectively engage
and restrict movement of the diaphragm. An external monitor may be
in electronic communication with the pressure transducer, and the
external monitor may comprise a signal analysis processor for
receiving the electronic signal from the pressure transducer. The
external monitor may be adapted to process the electronic signal
and transmit the electronic signal to a control unit.
[0027] A further embodiment is directed to a fluid delivery system
comprising a power injector adapted to interface with and actuate
at least one syringe, a fluid path set connected to the at least
one syringe and comprising a tubing element, and a pressure
transducer in continuous fluid communication with fluid in the
tubing element and adapted to measure fluid pressure in the tubing
element. Fluid communication may mean direct contact with a fluid
medium or indirect, for example, across a membrane or other barrier
to permit the pressure transducer to ascertain fluid pressure
readings in the tubing element. The pressure transducer comprises a
deformable element configured to deform in response to changing
fluid pressure in the tubing element. The pressure transducer
converts to an electronic signal a representation of the amount of
deformation of the deformable element to measure the changing fluid
pressure in the tubing element.
[0028] The pressure transducer may be configured to measure
pressure within the range of between about 0 mm Hg to about 300 mm
Hg, and the pressure transducer may be further configured such that
it remains in working condition after being exposed to pressure in
excess of about 60,000 mm Hg.
[0029] The pressure transducer may be configured to be placed in
fluid connection with a pressure port in fluid communication with
the tubing element.
[0030] The pressure transducer may be an optical pressure
transducer and the deformable element may be a flexible tube
enclosing the optical pressure transducer. The pressure transducer
may further comprise a radiation generator for promulgating a
radiation beam through the flexible tube, and a detector for
detecting the promulgated radiation beam. The flexible tube may be
configured to deform in response to fluid pressure in the tubing
element, and the pressure transducer may be configured to measure
the deformation of the flexible tube.
[0031] The deformable element may be a diaphragm which flexes in
response to changing fluid pressure within the tubing element, and
the pressure transducer may measure flexing of the diaphragm and
convert to an electronic signal a representation of the amount of
flexing of the diaphragm to measure the changing fluid pressure in
the tubing element. A guard may be provided to selectively engage
and restrict movement of the diaphragm.
[0032] An external monitor may be in electronic communication with
the pressure transducer. The external monitor may comprise a signal
analysis processor for receiving the electronic signal from the
pressure transducer and be adapted to process the electronic signal
and transmit the electronic signal to a control unit. A visual
display may be provided on the external monitor for displaying the
electronic signal for a user.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] For the purpose of facilitating understanding of this
disclosure, the accompanying drawings and description illustrate
certain embodiments, from which the various discussed structures,
construction, method of operation, and many advantages provided by
this disclosure may be understood and appreciated.
[0034] FIG. 1A is a perspective view of a fluid delivery system
with a removable pressure sensor according to one embodiment.
[0035] FIG. 1B is a perspective view of a fluid delivery system
with a pressure sensor associated with a fluid path set according
to another embodiment.
[0036] FIG. 1C is a perspective view of a fluid delivery system
with a hardwired pressure sensor according to a further
embodiment.
[0037] FIG. 2A is a perspective view of a fluid delivery system
with a removable pressure sensor according to one embodiment.
[0038] FIG. 2B is a perspective view of a fluid delivery system
with a pressure sensor associated with a fluid path set according
to another embodiment.
[0039] FIG. 3A is a perspective view of a fluid delivery system
including a hand manifold and removable pressure sensor, according
to one embodiment.
[0040] FIG. 3B is a perspective view of a fluid delivery system
including a hand manifold and pressure sensor according to another
embodiment.
[0041] FIG. 4 is a schematic view of a pressure sensor for use in a
fluid injection system, according to an embodiment of this
disclosure.
[0042] FIG. 5 is a perspective view of an optical pressure sensor
according to an embodiment of this disclosure.
[0043] FIG. 6 is a partial perspective view of a pressure sensor
including an external detector or monitor according to an
embodiment of this disclosure.
[0044] FIG. 7 is a perspective schematic view of a fluid tubing
element and a removable pressure sensor according to an embodiment
of this disclosure.
[0045] FIGS. 8A-8C are schematic views of a
micro-electro-mechanical (MEMs) pressure sensor according to an
embodiment of this disclosure.
DETAILED DESCRIPTION
[0046] For purposes of the description hereinafter, spatial
orientation terms, as used, shall relate to the referenced
embodiment as it is oriented in the accompanying drawing figures or
otherwise described in the following detailed description. However,
it is to be understood that the embodiments described hereinafter
may assume many alternative variations and configurations. It is
also to be understood that the specific components, devices, and
features illustrated in the accompanying drawings and described
herein are simply exemplary and should not be considered as
limiting.
[0047] FIGS. 1A-1C are perspective views of an exemplary embodiment
of a fluid delivery system 10. The fluid delivery system 10 is used
to deliver fluids to a patient during a medical injection
procedure. For example, the fluid delivery system 10 may be used
during an angiographic procedure to inject contrast media and
common flushing agents, such as saline, into the body of a patient.
Details of the fluid injection or delivery system 10 are disclosed
in U.S. patent application Ser. No. 09/982,518, filed on Oct. 18,
2001, now issued as U.S. Pat. No. 7,094,216 on Aug. 22, 2006
(hereinafter "the '216 patent"), and is assigned to the assignee of
the present application, the disclosure of which is incorporated
herein by reference in its entirety. Additional examples of fluid
delivery systems are disclosed in the following references: U.S.
patent application Ser. No. 10/825,866, filed on Apr. 16, 2004, now
issued U.S. Pat. No. 7,556,619 on Jul. 7, 2009 (hereinafter "the
'619 patent"); U.S. Pat. No. 8,337,456 to Schriver et al., issued
Dec. 25, 2012; U.S. Pat. No. 8,147,464 to Spohn et al., issued Apr.
3, 2012; and, U.S. patent application Ser. No. 11/004,670, now
published as U.S. 2008/0086087 on Apr. 10, 2008, each of which are
assigned to the assignee of the present application and the
disclosures of which are incorporated herein by reference in their
entireties.
[0048] The fluid delivery system 10 generally includes a powered
fluid injector 12 that is adapted to support and actuate a syringe
14 storing a first injection fluid for injection into a patient
during a medical procedure, such as an angiographic procedure. The
fluid injector 12 is generally used to supply the contrast media in
the syringe 14 under pressure to a fluid path set 16 and,
ultimately, a patient. The fluid injector 12 is optionally
controlled by a hand controller 18 to supply the contrast media at
discrete and preselected flow rates based on a physical input such
as a trigger plunger 20. The fluid delivery system 10 further
includes a second injection fluid that may be mixed with the first
injection fluid prior to being delivered to a patient or delivered
directly to the patient without mixing, depending on the mode of
operation of the fluid injector 12. The second fluid is advanced by
a pumping mechanism 22 such as a peristaltic pump. The powered
fluid injector 12 is operatively associated with a fluid control
module 24. The fluid control module 24 is generally adapted to
support at least portions of the fluid path set 16. The fluid path
set 16 is adapted to fluidly connect the syringe 14 to a source of
contrast media 26 and a source of saline 28, which is supplied to
the patient via the same catheter as the contrast media 26.
[0049] The fluid path set 16 may have single and multi-use
disposable sections and includes a first input line 30 in selective
fluid communication with the syringe 14, a second input line 32 in
selective fluid communication with the source of saline 28, a
downstream Y-connector 34 joining the first and second input lines
30, 32, and a catheter connector conduit 36. Additional aspects of
the fluid path set 16 may be found in the '216 patent and the '619
patent referenced above. The catheter connector conduit 36 is a
disposable tubing section that connects the fluid path set 16 to a
catheter (not shown) that is inserted within a patient for
supplying the contrast media 26 and saline 28 to the patient.
Desirably, the catheter connector conduit 36 is removably connected
by a suitable connector 38 to a stopcock valve 40 that is provided
between the Y-connector 34 and the catheter connector conduit 36.
The stopcock valve 40 may form a break point between reusable
components of the fluid path set 16 and the disposable, single-use
catheter connector conduit 36 in one embodiment. The stopcock valve
40 permits a user to isolate the reusable upstream components of
the fluid path set 16 so that, when the stopcock valve 40 is in a
closed position, a user can remove and replace the catheter
connector conduit 36, and so that the multi-patient section of the
fluid delivery system 10 can be used by another patient. The
stopcock 40 is merely an exemplary structure for isolating the
upstream components from the catheter connector conduit 36 and may
be replaced by any suitable aseptic connector structure, but the
stopcock 40 has the advantage of being manually actuated.
[0050] With specific reference to FIG. 1A, the fluid path set 16
may be configured with a pressure port 42, for example formed as a
port on the connector 38 adapted for connection with the stopcock
valve 40. A pressure sensor 50a according one embodiment is
configured to be removably coupled with the pressure port 42. It is
desirable to position the pressure port 42 and the associated
pressure sensor 50a as close to the catheter (not shown) as
possible and, more specifically, to the patient to reduce the
possibility that a pressure drop through the catheter and the
catheter connector conduit 36 will reduce the reliability and
accuracy of pressure measurements. The pressure sensor 50a is
generally adapted to measure hemodynamic waves in tubing portion 44
of the catheter connector conduit 36. The hemodynamic waves provide
an indication of intra-vascular blood pressure. The measured blood
pressure is used, for example, to determine the location of a
catheter within an access vein, artery, or heart chamber. More
particularly, different areas of the heart and surrounding
vasculature have different pressures. Therefore, monitoring
intra-coronary pressure provides an effective way to identify the
coronary area (e.g., the right atrium, right ventricle, pulmonary
artery, left ventricle, or aortic root) where the catheter is
located. The pressure in the fluid access line also provides a
useful indication of whether the fluid path is ready for injection.
Further, intravascular pressure can also be used for thrombosis
detection. More specifically, the quality of the hemodynamic signal
decays as the blood begins to clot. Therefore, as the catheter
approaches the clotting area, a user will observe a noticeable
decay in signal quality. If other explanations for the decay are
eliminated, then the practitioner may infer that a clot is forming.
The hemodynamic signal also provides an early warning for
arrhythmias. More specifically, the practitioner will observe an
almost immediate change in hemodynamic signal during the onset of
atrial fibrillation, bradycardia, or tachycardia. Once warned about
onset of arrhythmia, the practitioner can provide appropriate
treatments to the patient.
[0051] The pressure sensor 50a may have numerous functional
elements and configurations, including optical sensors, mechanical
sensors, micro-electrical-mechanical (MEMs) sensors, and the like.
The sensor 50a may be removable from the pressure port 42, thereby
potentially allowing the sensor 50a to be reused even as the
catheter connector conduit 36 is disposed of as medical waste. The
pressure sensor 50a is intended to be in constant fluid
communication with the fluid flow path set 16, or at least
configured such that pressure measured by the pressure sensor 50a
is essentially equivalent to fluid pressure in the fluid flow path
set 16, even if there is no direct contact between patient fluid
and the pressure sensor 50a. The pressure sensor 50a is configured
with sufficient sensitivity to measure pressure at least within a
range of between about 0 mm Hg and about 300 mm Hg. The pressure
sensor 50a is also configured to withstand pressure in excess of
1200 psi (about 63,000 mm Hg) without damaging the pressure sensor
50a. In this way, pressurized fluid from the powered fluid injector
12 may pass through the fluid path set 16 without damaging the
pressure sensor 50a, while the pressure sensor 50a remains in fluid
communication or contact with the fluid in the catheter connector
conduit 36 via the continuously-open pressure port 42. The pressure
sensor 50a may be a disposable, one-time-use device or may be
reusable, as discussed above, if contamination between the pressure
sensor 50a and patient fluid is sufficiently limited or prevented
by some means, such as by use of a protective membrane or similar
structure.
[0052] The pressure sensor 50a is illustrated as being coupled to a
control unit 90 via a hemodynamic signal cable 92. The control unit
90 may be a computer, external computer network, or dedicated
analysis system for displaying and/or analyzing data recorded by
the pressure sensor 50a. Exemplary data analysis and processing
systems capable of providing necessary detailed analysis of the
measured hemodynamic signal include, but are not limited to,
Avanta.TM., Arterion.TM., Panel PC GUI, and software packages
residing on an Angio Informatics PC, all of which are proprietary
to Bayer HealthCare LLC the assignee of the present application.
Alternative hemodynamic monitoring and analysis systems, as are
known in the art, may also be used to process and analyze
hemodynamic signals provided by the pressure sensor 50a.
[0053] With reference to FIG. 1B, another embodiment of a pressure
sensor 50b is shown associated with the fluid path set 16. For
example, the pressure sensor 50b may be associated with the
disposable catheter connector conduit 36. As illustrated, the
catheter connector conduit 36 may be provided with opposed end
connectors 54, 56 for establishing respective fluid connections
between the stopcock valve 40 and the catheter (not shown). The
pressure sensor 50b is disposed between the opposed end connectors
54, 56 and, as was the case with the pressure sensor 50a described
previously, the pressure sensor 50b is a high pressure sensor
adapted to withstand pressure in excess of 60,000 mm Hg. As
discussed further herein, a pressure transducer (not shown) is
disposed within the tubing portion 44 of the catheter connector
conduit 36. The pressure transducer may be an optical transducer,
mechanical transducer, MEMs transducer, or any other electronic
device or assembly for measuring changes in fluid pressure. As will
be described in greater detail herein, the pressure sensor 50b, may
further include an external signal detector or monitor 60 in wired
or wireless connection with the pressure transducer (not shown)
disposed within the disposable tubing portion 44 of the catheter
connector conduit 36. The pressure transducer is configured to
transmit measured hemodynamic signals to the external monitor 60.
For example, the pressure transducer may include a wireless
transmitter for transmission of measured hemodynamic signals to the
external monitor 60. Other devices and structures for information
connection between the pressure transducer and external monitor 60
may include, but are not limited to, wired connections, radio
waves, and others, and these alternative modalities may also be
used for establishing an information connection between the
pressure transducer and the external monitor 60.
[0054] In summary, in the present embodiment, the pressure sensor
50b is intended to be used only once per patient, as the pressure
transducer (not shown) will likely come into physical contact with
the medium that is a part of a fluid column extending from the
patient through a catheter (not shown) to the tubing portion 44 of
the catheter connector conduit 36. Additionally, the external
monitor 60 is generally adapted to acquire the measured hemodynamic
signals from the pressure transducer and may optionally have its
own hemodynamic signal analysis capability. For example, the
external monitor 60 may be adapted to processes or analyze the
hemodynamic signals by, for example, excluding pressure values that
fall outside of normal human intra-vascular pressure range. Other
capabilities of the external monitor 60 are described herein, and
the external monitor 60 may further include a display capability to
provide the user with certain information regarding the hemodynamic
signals measured by the pressure transducer. After
analyses/processing, the measured hemodynamic signals may be
provided to the control unit 90 through a wired connection provided
by the hemodynamic signal cable 92 or a wireless connection. As
another alternative, the external monitor 60 may merely be used to
collect and/or transfer the measured hemodynamic signals measured
by the pressure transducer to a remote control unit, such as the
control unit 90. The control unit 90 may be a computer, external
computer network, or dedicated analysis system for displaying
and/or analyzing data recorded by the pressure sensor 50b, and this
control feature may reside, for example, in the control system for
the fluid injector 12 shown in FIGS. 1A-1C, in one embodiment.
[0055] With reference to FIG. 1C, a portion of the fluid path set
16 is shown and illustrates another embodiment of the pressure
sensor 50c disposed between the opposed end connectors 54, 56 of
the catheter connector conduit 36. As was the case with the
pressure sensor 50b described previously, the pressure sensor 50c
is a high pressure sensor adapted to withstand pressure in excess
of 60,000 mm Hg. The pressure sensor 50c may again be an optical
sensor, mechanical sensor, or MEMs sensor as non-limiting examples.
This embodiment illustrates a pressure transducer 52 of the
pressure sensor 50c disposed within the catheter connector conduit
36. The pressure transducer 52 is disposed inline within the tubing
element or portion 44 of the catheter connector conduit 36, and the
pressure transducer 52 is suitable for use in connection with the
pressure sensor 50b discussed above in connection with FIG. 1B. In
this embodiment, the pressure transducer 52 is shown hardwired to
the control unit 90 by the hemodynamic signal cable 92, which
extends from the pressure transducer 52, through the tubing element
or portion 44 of the catheter connector conduit 36, and outward
from the catheter connector conduit 36 via a side port 58. The side
port 58 may be, for example, provided on end connector 54 used to
establish a fluid connection with the stopcock valve 40. In the
embodiment of FIG. 1C, the cable 92 is depicted as extending
through a portion of the fluid path set 16 and exiting the fluid
path set 16 through side port 58. However, it is understood that
the cable 44 may exit the fluid path set 16 at any position along
the fluid path set 16, and even extend to the fluid control module
24.
[0056] FIGS. 2A and 2B illustrate another embodiment of a fluid
delivery system 100 having a powered fluid injector 102 adapted to
accept and actuate a plurality of syringes, such as the two
syringes 104 illustrated. The syringes 104 are fluidly connected to
two (2) fluid sources, such as a source of saline 109 and a source
of contrast media 110, or any two desired medical fluids. The fluid
injector 102 is desirably at least a dual-syringe injector, wherein
the two (2) fluid delivery syringes 104 are oriented in a
side-by-side relationship and which are separately actuated by
respective piston elements associated with the fluid injector 102.
A fluid path set 108 may be interfaced with the syringes 104
associated with the fluid injector 102 in the fluid delivery system
100. In particular, the fluid injector 102 may include a fluid
control module 106 that is generally adapted to support and
interface the syringes 104 with the fluid path set 108; the fluid
control module 106 may have control valves and like elements to
control the fluid flow through the fluid path set 108 connected to
the syringes 104. A suitable multi-syringe fluid injector for use
with the above-described system is described in U.S. patent
application Ser. No. 13/386,765, filed on Jan. 24, 2012, which
published as U.S. Patent Application Publication No. 2012/0123257,
and is assigned to the assignee of the present application, the
disclosure of which is incorporated herein by reference in its
entirety. Other relevant multi-fluid delivery systems are disclosed
in U.S. patent application Ser. No. 10/159,592, filed on May 30,
2002 (published as U.S. 2004/0064041), and U.S. patent application
Ser. No. 10/722,370, filed Nov. 25, 2003 (published as U.S.
2005/0113754), each of which are assigned to the assignee of the
present application and the disclosures of which are incorporated
herein by reference in their entireties.
[0057] The fluid path set 108 may have single and multi-use
disposable sections in a similar manner to the fluid path set 16
described previously. The fluid path set 108 includes a first input
line 112 in selective fluid communication with a first syringe
104a, a second input line 114 in selective fluid communication with
a second syringe 104b, a downstream Y-connector 118 joining the
first and second input lines 112, 114, and a catheter connector
conduit 136. The catheter connector conduit 136 is again a
disposable tubing section that connects the fluid path set 108 to a
catheter (not shown) that is inserted within a patient for
supplying the fluids from the saline source 109 and the contrast
media source 110 to the patient. Desirably, the catheter connector
conduit 136 is removably connected by a suitable connector 138 to a
stopcock valve 140 that is provided between the Y-connector and the
catheter connector conduit 136. The stopcock valve 140 may form a
break point between reusable components of the fluid path set 108
and the disposable catheter connector conduit 136 in one
embodiment. This configuration permits a user to isolate the
reusable upstream components of the fluid path set 108 so that,
when the stopcock valve 140 is in a closed position, a user can
remove and replace the catheter connector conduit 136, and so that
the multi-patient section of the fluid delivery system 100 can be
used by another patient. The stopcock 140 is merely an exemplary
structure for isolating the upstream components from the catheter
connector conduit 136 and may be replaced by any suitable aseptic
connector structure, but the stopcock 140 has the advantage of
being manually actuated.
[0058] As in the embodiment of FIG. 1A, the embodiment of FIG. 2A
includes a pressure port 142, but now positioned further downstream
from the stopcock valve 140 and the Y-connector 118. Thus, the
pressure port 142 is now shown as a branch port or element on a
tubing portion 144 of the catheter connector conduit 136. In the
present embodiment, the same pressure sensor 50a according to the
embodiment illustrated in FIG. 1A is removably coupled to the
pressure port 142. The removable pressure sensor 50a, as noted
previously, is a high pressure sensor which is configured to have
good sensitivity at pressures within the range of human
intravascular pressure, but which also withstands fluid pressures
in excess of 60,000 mm Hg. The pressure sensor 50a may again be
connected to the control unit 90 through the hemodynamic signal
cable 92 or may be wirelessly coupled to the control unit 90.
[0059] With reference to FIG. 2B, another embodiment of the fluid
delivery system 100 is shown, which is similar to the fluid
delivery system 10 of FIG. 1B. In FIG. 2B, the pressure sensor 50b
is shown associated with the fluid path set 108. In particular, the
pressure sensor 50b is shown associated with the disposable
catheter connector conduit 136, which further comprises opposed end
connectors 154, 156 for establishing respective fluid connections
between the stopcock valve 140 and a catheter (not shown). The
pressure sensor 50b is disposed between the opposed end connectors
54, 56 and, as was the case with the pressure sensor 50a described
previously, the pressure sensor 50b is a high pressure sensor
adapted to withstand pressure in excess of 60,000 mm Hg. As
discussed briefly in connection with FIG. 1C and in further detail
herein, a pressure transducer (not shown) is disposed within the
tubing portion 144 of the catheter connector conduit 36. The
pressure transducer may be an optical transducer, mechanical
transducer, MEMs transducer, or any other electronic device or
assembly for measuring changes in fluid pressure. As will be
described in greater detail herein, the pressure sensor 50b may
further include, or be connected to, an external signal detector or
monitor 60 in wired or wireless connection with the pressure
transducer (not shown) disposed within the disposable tubing
portion 144 of the catheter connector conduit 136. As with the
embodiment of the fluid delivery system 10 of FIG. 1B, the external
detector or monitor 60 may be configured to process and analyze
hemodynamic signals measured by the pressure transducer, or the
external detector or monitor 60 may simply be used to collect and
transfer the measured hemodynamic signals measured by the pressure
transducer to a remote control unit, such as the control unit 90.
The control unit 90 may be a computer, external computer network,
or dedicated analysis system for displaying and/or analyzing data
recorded by the pressure sensor 50b, and this control feature may
reside, for example, in the control system for the fluid injector
102 shown in FIGS. 2A-2B, in one embodiment. The connection between
the pressure transducer (not shown) and the external monitor
detector 60 may be a wireless or wired connection.
[0060] With reference to FIGS. 3A and 3B, a further embodiment of a
fluid delivery system 200 is shown and includes a hand-operated
manifold 202 adapted for fluid connection to a plurality of fluid
sources. An exemplary hand manifold for the hand-operated manifold
202 is disclosed in U.S. patent application Ser. No. 13/755,883,
filed Jan. 31, 2013, assigned to the assignee of the present
application, the disclosure of which is incorporated herein by
reference. The fluid delivery system 200 may be connected to a
patient connector fluid path set 204 having an optional tube
stabilizer 206. The fluid sources may include a low pressure, hand
operated syringe 208 and a high pressure syringe 210 adapted for
mechanical interface with and actuation by a powered fluid injector
(not shown). A suitable high pressure syringe 210 adapted to
interface with a powered fluid injector may be found in United
States Patent Application Publication No. 2009/0216192 to Schriver,
et al. The high pressure syringe 210 generally comprises an
elongated, cylindrical syringe body 212 defining an expansion
section 214 at the open proximal end. Tubing 216 extends from the
high pressure syringe 210 to the hand manifold 202.
[0061] The hand manifold 202 includes a manifold housing 218 formed
to support a plurality of fluid control valves 220 that are
connected in series with one another. The manifold housing 218 is
generally L-shaped and defines a pocket 222 adapted to accept and
support the fluid control valves 220. As shown in FIGS. 3A and 3B,
each fluid control valve 220 includes at least a first port 228, a
second port 230, and a third port 232. For the first fluid control
valve 220, the first port 228 is connected to the low pressure
syringe 208, the second port 230 is the outflow port, and the third
port 230 is fluidly connected to the high pressure syringe 210. The
second fluid control valve 220 is adapted to connect the first
fluid control valve 220 with a catheter connector conduit 236
having a similar configuration to previous embodiments of the
catheter connector conduit 36, 136. The catheter connector conduit
236 comprises a tubing portion or element 238 having a distal
connector 240 for connection to a catheter (not shown). In the
embodiment of FIG. 3A, the catheter connector conduit 236 includes
a pressure port 242. The catheter connector conduit 236 further
comprises a proximal end connector 244. For the second fluid
control valve 220, the first port 228 is fluidly connected to the
outflow or second port 230 of the first fluid control valve 220,
the second port 230 is removably connected to the proximal end
connector 244 via a suitable connector element 246, and the third
port 232 is available for connection to another fluid source (not
shown) such as a source of saline. Thus, the manifold 202 is
arranged so that fluid passes from the second port 230 of the first
fluid control valve 220 to the first port 228 of the second fluid
control valve 220.
[0062] As shown in FIG. 3A, in the present embodiment, the same
pressure sensor 50a according to the embodiment illustrated in
FIGS. 1A and 2A is removably coupled to the pressure port 242. The
removable pressure sensor 50a, as noted previously, is a high
pressure sensor which is configured to have good sensitivity at
pressures within the range of human intra-vascular pressure, but
which also withstands fluid pressures in excess of 60,000 mm Hg.
The pressure sensor 50a may again be connected to the control unit
90 through the hemodynamic signal cable 92 or may be wirelessly
coupled to the control unit 90.
[0063] With reference to FIG. 3B, the pressure sensor 50b discussed
previously may be associated with the catheter connector conduit
236. In FIG. 3B, the pressure sensor 50b is shown associated with
the fluid path set 204. In particular, the pressure sensor 50b is
shown associated with the disposable catheter connector conduit
236. The pressure sensor 50b is disposed between the opposed end
connectors 244, 246 and adjacent the tube stabilizer 206. The
pressure sensor 50b is again a high pressure sensor adapted to
withstand pressure in excess of 60,000 mm Hg. As discussed briefly
in connection with FIG. 1C and in further detail herein, a pressure
transducer (not shown) is disposed within the tubing portion 238 of
the catheter connector conduit 236. The pressure transducer may be
an optical transducer, mechanical transducer, MEMs transducer, or
any other electronic device or assembly for measuring changes in
fluid pressure. As will be described in greater detail herein, the
pressure sensor 50b, may further include, or be connected to, an
external signal detector or monitor 60 in wired or wireless
connection with the pressure transducer (not shown) disposed within
the disposable tubing portion 238 of the catheter connector conduit
236. As with the embodiment of the fluid delivery system 10 of FIG.
1B and the fluid delivery system 100 of FIG. 2B, the external
detector or monitor 60 may be configured to process and analyze
hemodynamic signals measured by the pressure transducer, or the
external detector or monitor 60 may simply collect and relay the
hemodynamic signals measured by the pressure transducer to a remote
control unit, such as the control unit 90. The control unit 90 may
be a computer, external computer network, or dedicated analysis
system for displaying and/or analyzing data recorded by the
pressure sensor 50b, and this control feature may reside, for
example, in the control system for the fluid injector 102 operating
the high pressure syringe 210 shown in FIGS. 3A-3B, in one
embodiment. The connection between the pressure transducer (not
shown) and the external monitor detector 60 may be a wireless or
wired connection.
[0064] Having described a number of exemplary embodiments of fluid
delivery systems 10, 100, and 200, various exemplary embodiments of
the pressure sensors 50a, 50b, 50c and associated control units
will now be described. With reference to FIGS. 4-6, an embodiment
of an in-line pressure sensor 300 that may be used as the pressure
sensor 50b in the embodiments, described previously, is shown. The
pressure sensor 300 includes an electronic pressure transducer 302
enclosed within a disposable tube 304. The disposable tube 304 may
be any of the disposable tubing elements or portions 44, 144, or
238 depicted in FIGS. 1B, 2B, and 3B, respectively. Thus, the
disposable tube 304 is a generic representation of the foregoing
tubing elements or portions 44, 144, or 238 forming part of the
catheter connector conduit 36 shown in FIG. 1B, the catheter
connector conduit 136 shown in FIG. 2B, or the catheter connector
conduit 236 shown in FIG. 3B. The disposable tube 304 is intended
to be representative of any tubing element or section wherein it is
desired to obtain hemodynamic pressure readings from a patient. The
pressure transducer 302 is in informational electronic connection
with an external detector or monitor 60. As described above in
connection with the previously described embodiments, the
connection may be any wired or wireless connection as is known in
the art. In certain embodiments, the transmitted signal may be
received by a signal processor 320 included within the external
detector or monitor 60. The signal may be delivered from the
external detector or monitor 60 to an external source through a
standard interface cable 92, as described previously.
[0065] The signal processor 320 is configured to receive the
hemodynamic signals measured by the pressure transducer 302 and to
selectively transmit the signals to an external source such as an
external control unit, computer, portable electronic device, or
other dedicated electronic device for receiving, displaying, and
analyzing the measured signals. The signal processor 320 may be
configured to analyze data received from the pressure transducer
302 and to selectively exclude irrelevant data. For example,
pressure readings that are orders of magnitude above typical
intra-coronary pressures may be assumed to be incorrect or caused
by fluid injection through the fluid path. The signal analysis
processor 320 may be configured to exclude such readings rather
than transferring such readings to the control unit 90.
[0066] With specific reference to FIGS. 5, in one embodiment, the
pressure sensor 300 is an optical sensor which further includes an
inner tube 310 provided within the disposable tube 304. The inner
tube 310 is formed from a flexible material, such that the tube 310
deforms in response to increasing fluid pressure in the disposable
tube 304. The pressure transducer 302 is configured to measure
deformation of the inner tube 310 and includes a radiation
generator 312 and receiver 314 disposed within the deformable inner
tube 310. The radiation generator 312 is configured to promulgate a
radiation beam through the inner tube 310, allowing the beam to
reflect from an interior surface 316 of the inner tube 310. The
reflected radiation wave is received by the receiver 314, which may
be integral with the radiation generator 312 or may be a separate
receiving element. As fluid pressure increases, the inner tube, or
deformable element 310 deforms altering the reflection angle,
phase, or period duration of the reflected beam. Variations in the
reflected beam are monitored by the signal processor 320 or control
unit 90 and used to determine the amount of deformation of the
deformable inner tube 310. Deformation of the inner tube 310
corresponds to the fluid pressure in the disposable tube 304.
Pressure sensors 300 having different configurations may also be
used. For example, an optical sensor may be projected on a
deformable diaphragm or other deformable structure may be used in
the disposable tube 304 to measure fluid pressure, such as the
embodiment described in connection with FIGS. 8A-8C described
herein.
[0067] With further reference to FIG. 6, in one embodiment, the
signal measured by the pressure transducer 302 is delivered to the
external detector 60 and the signal processor 320 for analysis.
Signal analysis performed by the signal processor 320 can be
delivered to a user (e.g., physician and clinical staff) in
multiple ways. In the simplest form, the analyzed signal itself is
provided on monitoring equipment already available in typical
Interventional Radiology and Cardiology suites Similarly, the
signal can be displayed on an overhead monitor. Alternatively, the
hemodynamic waveform can be provided on a computer monitor
dedicated for that purpose, to provide an increased level of
analysis for a user. The increased analysis and multiple viewing
locations reduces the need for constant monitoring of the
hemodynamic signal, provides visual feedback about the condition of
the patient and operation of the fluid delivery system, and may
provide for simultaneous automated backup of recorded data.
[0068] In certain embodiments, the signal processor 320 may also be
configured to determine information about the fluid delivery system
10, 100, 200, including whether the fluid delivery system 10, 100,
200 is connected to a patient, whether the system is ready for use,
and whether a fluid injection can safely be performed. For example,
the signal process 320 may be configured to compare a hemodynamic
pressure signal measured by the pressure sensor 300 with an
expected pressure value, such as an expected pressure value when a
specific fluid volume is injected through the fluid delivery system
10, 100, 200. If the pressure measured by the pressure sensor 300
is less than the expected pressure value, the signal processor 320
determines that air may be present in the fluid line. Accordingly,
the fluid line must be purged to remove air bubbles before using
the fluid delivery system 10, 100, 200 to inject fluid into a
patient. Similarly, in a further non-limiting embodiment, the
signal processor 320 may be configured to predict the size of air
bubbles present in a fluid line by comparing the measured pressure
(e.g., the measured systolic and diastolic pressures) provided by
the pressure sensor 300, according to a predetermined algorithm for
comparing measured and expected pressure values. Similarly, when
measured pressure indicates that the fluid delivery system 10, 100,
200 is connected to a patient, the signal processor 320 may prevent
a user from purging air through the system. If necessary, the
signal processor 320 may also trigger an audible or visual alarm to
alert a user about certain dangerous situations.
[0069] In certain further embodiments, the pressure sensor 300 may
be configured to provide a user, such as a clinician or
practitioner, with data related to fluid flow through the fluid
delivery system 10, 100, 200 and patient intravascular pressure
data directly on the pressure sensor 300 itself. As mentioned
previously, fluid pressure may fall outside of the normal
intracoronary range for a number of reasons, such as when a
thrombosis is forming in close proximity to the catheter, or when
onset of arrhythmia is imminent. As an example, if abnormal
intracoronary pressure is observed, a practitioner would likely
want to perform additional evaluation of the fluid path and/or
patient before using the fluid delivery device to inject fluid into
the patient.
[0070] Accordingly, in an exemplary embodiment shown in FIG. 6, the
external detector or monitor 60 includes a visual display 322, for
example having one or more visual indicators 324 configured to
provide relevant information about the condition of the patient
and/or a fluid path, such as fluid pressure in the fluid path. In
the present disclosure, such a fluid path may include, for example,
such as the fluid pressure within tubing elements or portions 44,
144, or 238 forming part of the catheter connector conduit 36 shown
in FIG. 1B, the catheter connector conduit 136 shown in FIG. 2B, or
the catheter connector conduit 236 shown in FIG. 3B, particularly
whether the measured pressure is within a normal range. The visual
indicators 324 may include, as an example, a series of colored
light emitting diodes (LEDs) arranged on the housing of the
external detector or monitor 60, a button or features on a small
user interactive display, and like devices. In one embodiment, a
warning indicator 326, which may be a red LED, indicates that the
waveform currently being observed is outside the bounds of normal
human intra-coronary pressure. Examples of reasons why such a
reading is received include that the patient's heart rate is above
220 beats per minute, that no heart rate is observed, or that a
waveform is so dampened that it could not signify heart function. A
caution indicator 328 may indicate that the waveform being observed
is within a possible human range, but outside of the normal range
for a patient. Examples of reasons for such a reading include
occurrence of a change to systolic or diastolic pressures, loss of
signal properties from the pressure sensor 300, or signal
properties that indicate boundary conditions of the catheter. A
ready-for-use indicator 330, possibly signified by a green LED, may
signal that the waveform currently being monitored is typical for
patients. It is noted that a green indicator may not be an
indication that a patient is in good health, but merely an
indication of good hemodynamic signal. While the visual indicators
324 are depicted as being positioned on the visual display 322 of
the external detector or monitor 60, it will also be understood
that the visual indicators 324 may be positioned at other locations
within the scope of this disclosure. For example, the visual
indicators 324 may be on the control unit 90 or some other external
device. The visual indicators 324 may also be displayed on a
computer monitor or other existing display unit already present in
an operating room or imaging/cardiac suite.
[0071] With reference to FIG. 7, a pressure sensor 400 is depicted
that may be used as the pressure sensor 50a in the embodiments
described previously is shown. The pressure sensor 400 is
configured to be removably inserted in a pressure port 410 such as
the pressure ports 42, 142, and 242 depicted in FIGS. 1A, 2A, and
3A, respectively. The pressure sensor 400 includes a pressure
transducer 402. A hemodynamic interface cable 412 is connected to
the pressure sensor 400. The interface cable 412 extends to the
control unit 90, discussed previously, such as a computer, handheld
computer, or dedicated monitoring and analysis device. The pressure
sensor 400 may be a reusable sensor, which can be used in fluid
path sets for different patients rather than being disposed of
following each use. In this case, the pressure sensor 400 and/or
pressure port 410 may be lined with a protective material 414 to
prevent direct contact between patient fluid contained in a fluid
tubing path 404, such as tubing elements or portions 44, 144, or
238, and the pressure sensor 400. The pressure sensor 400 may
further include a deformable diaphragm or element 406 that flexes
in response to fluid pressure from the fluid delivery system 10,
100, 200. The pressure transducer 402, such as an optical
transducer, mechanical transducer, or MEMs transducer may be used
to measure the deformation of the diaphragm 406. In certain
embodiments, the diaphragm 406 is anchored to a sensor housing
416.
[0072] With reference to FIGS. 8A-8C, the pressure sensors 300, 400
may be provided with a micro-electro-mechanical (MEMs) based
electronic pressure transducer 502. The following discussion of the
MEMs based electronic pressure transducer 502 proceeds in the
context of the pressure sensor 400 for expediency in explaining the
operational features of FIGS. 8A-8C, but this specific context
should not be deemed as limiting, and are applicable to, for
example, the pressure sensor 50b described previously. Thus, the
concepts described in connection with FIGS. 8A-8C may be applied
with respect to pressure sensor 300 and, thus, pressure sensor 50b
described above. In FIGS. 8A-8C, the MEMs based electronic pressure
transducer 502 measures deformation of the flexible diaphragm 406.
As external fluid pressure increases, the flex or deformation of
the diaphragm 406 proportionally increases. The pressure transducer
502 includes electronic components (not shown) to convert to an
electronic signal a representation of the amount of the deflection
or deformation of the diaphragm 406; such a deflection or
deformation and measurement thereof is analogous to measurements
taken using strain gauges. As described above, with previously
known mechanical pressure transducers, substantial increases in
pressure damages the mechanical pressure transducers rendering the
pressure sensor unusable. To address this problem, the pressure
sensors 300, 400 further includes a guard 508 or backstop to
prevent the diaphragm 406 from deforming far enough to cause
irreversible damage to the pressure transducer 502. The guard 508
is configured to engage and counteract deformation of the diaphragm
406 when pressure exceeds a predetermined value. The diaphragm 406
remains engaged to the guard 508 until the fluid pressure decreases
below the predetermined value.
[0073] More specifically, as shown in FIG. 8A, when no fluid
pressure is present (P=0 mm Hg), the diaphragm 406 is free from
biasing force and a gap of distance D1 exists between the diaphragm
406 and guard 508. As pressure increases, the diaphragm 406 deforms
reducing the distance D2 between the diaphragm 406 and guard 508.
When pressure exceeds the desired monitoring range (e.g., a range
of possible human intracoronary pressure) the diaphragm 406
contacts the guard 508, meaning that the distance D3 between the
diaphragm 406 and guard 508 is 0. It is noted that, in this
configuration, the pressure sensor 400 cannot provide a pressure
reading after the diaphragm 406 engages the guard 508, or exhibits
a maximum reading. In certain embodiments, the pressure sensor 400
may then produce an indication that pressure is unreadable or
indeterminable. The pressure sensor 400 becomes operational again
once pressure decreases to within the predetermined range.
[0074] While specific embodiments of the high pressure sensor for a
fluid delivery system having been described in detail, it will be
appreciated by those skilled in the art that various modifications
and alternatives to those details could be developed in light of
the overall teachings of the disclosure. Accordingly, the
particular arrangements disclosed are meant to be illustrative only
and not limiting as to the scope of invention which is to be given
the full breadth of the claims appended and any and all equivalents
thereof.
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