U.S. patent application number 15/350703 was filed with the patent office on 2017-03-02 for infusion pump apparatus, method and system.
The applicant listed for this patent is DEKA Products Limited Partnership. Invention is credited to Kevin A. Durand, Larry B. Gray, Dean Kamen, John M. Kerwin, Gregory R. Lanier, Jr., Marc A. Mandro, Colin H. Murphy.
Application Number | 20170056606 15/350703 |
Document ID | / |
Family ID | 43978069 |
Filed Date | 2017-03-02 |
United States Patent
Application |
20170056606 |
Kind Code |
A1 |
Kamen; Dean ; et
al. |
March 2, 2017 |
Infusion Pump Apparatus, Method and System
Abstract
A system is disclosed. The system includes a fill adapter device
including a heat exchanger which includes a heating element and a
fluid pathway, the fluid pathway fluidly connected to a filling
needle input, whereby fluid enters the heat exchanger through the
filling needle input and flows through the fluid pathway and
whereby the fluid is heated by the heating element. The system also
includes a reservoir including a plunger and a plunger rod and a
filling needle configured to be removably attached to the
reservoir, wherein the fill adapter is configured to be attached to
a vial of fluid and wherein fluid from the vial flows through the
fluid pathway and is heated and loaded into the reservoir through
the filling needle.
Inventors: |
Kamen; Dean; (Bedford,
NH) ; Kerwin; John M.; (Manchester, NH) ;
Mandro; Marc A.; (Bow, NH) ; Durand; Kevin A.;
(Westboro, MA) ; Gray; Larry B.; (Merrimack,
NH) ; Lanier, Jr.; Gregory R.; (Merrimack, NH)
; Murphy; Colin H.; (Cambridge, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DEKA Products Limited Partnership |
Manchester |
NH |
US |
|
|
Family ID: |
43978069 |
Appl. No.: |
15/350703 |
Filed: |
November 14, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13021369 |
Feb 4, 2011 |
9492607 |
|
|
15350703 |
|
|
|
|
61301957 |
Feb 5, 2010 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 2205/502 20130101;
A61M 2205/3569 20130101; A61M 2205/70 20130101; A61M 2209/045
20130101; Y02A 90/26 20180101; A61M 5/14244 20130101; A61M 2205/368
20130101; A61M 2205/7536 20130101; A61M 5/1684 20130101; A61M 5/445
20130101; A61M 2205/3389 20130101; A61M 5/385 20130101; A61M
2205/3653 20130101; A61M 5/5086 20130101; A61M 2005/14264 20130101;
A61M 2205/3606 20130101; A61M 2005/16863 20130101; A61M 2205/18
20130101; Y02A 90/10 20180101; A61M 2205/3673 20130101; A61M
2205/3693 20130101; A61M 2230/201 20130101; A61M 2005/1402
20130101; A61M 2205/3358 20130101; A61M 2205/3592 20130101; A61M
2205/364 20130101; A61M 2205/52 20130101; A61M 2205/3686 20130101;
A61M 2205/702 20130101; A61M 5/44 20130101; A61M 5/16886 20130101;
A61M 2205/3372 20130101; A61M 2205/3561 20130101; A61M 2205/3368
20130101; A61M 5/16831 20130101; A61M 2205/505 20130101 |
International
Class: |
A61M 5/44 20060101
A61M005/44; A61M 5/168 20060101 A61M005/168; A61M 5/142 20060101
A61M005/142; A61M 5/50 20060101 A61M005/50; A61M 5/38 20060101
A61M005/38 |
Claims
1. A system comprising: a fill adapter device comprising: a heat
exchanger comprising: a heating element; and a fluid pathway,
whereby fluid enters the heat exchanger and flows through the fluid
pathway and whereby the fluid is heated by the heating element; and
wherein the fill adapter is configured to be attached to a vial of
fluid and wherein fluid from the vial flows through the fluid
pathway and is heated.
2. The system of claim 1, further comprising a reservoir including
a plunger and a plunger rod.
3. The system of claim 1, wherein the fluid pathway fluidly
connected to a filling needle input, whereby fluid enters the heat
exchanger through the filling needle input.
4. The system of claim 2, further comprising a filling needle
configured to be removably attached to the reservoir.
5. The system of claim 4, wherein fluid flows through the fluid
pathway and is heated and loaded into the reservoir through the
filling needle.
6. The fill adapter of claim 1 further comprising a pump to pump
fluid into the fluid pathway at a predetermined rate.
7. The fill adapter of claim 1 further comprising a check valve for
metering fluid into the fluid pathway whereby the rate of flow of
fluid through the heat exchanger is controller.
8. The fill adapter of claim 1 further comprising a processor for
controlling the heating of the fluid according to one or more
preprogrammed profiles.
9. The fill adapter of claim 1 wherein the filling needle input is
a septum.
10. The fill adapter of claim 1 further comprising an air trap
whereby the air trap allows air to flow out of the heat
exchanger.
11. The fill adapter of claim 10 wherein the air trap comprising a
hydrophobic filter.
12. A fill adapter device comprising: a heat exchanger comprising:
a pump; a heating element; and a fluid pathway, the fluid pathway
fluidly connected to a filling needle input and a vial, whereby
fluid from the vial is pumped into the fluid pathway at a
predetermined rate and wherein fluid enters the heat exchanger and
flows through the fluid pathway and whereby the fluid is heated by
the heating element.
13. The fill adapter of claim 12 further comprising a check valve
for metering fluid into the fluid pathway whereby the rate of flow
of fluid through the heat exchanger is controller.
14. The fill adapter of claim 12 further comprising a processor for
controlling the heating of the fluid according to one or more
preprogrammed profiles.
15. The fill adapter of claim 12 further comprising wherein the
fill adapter is configured to be attached to a vial of fluid.
16. The fill adapter of claim 12 wherein the filling needle input
is a septum.
17. The fill adapter of claim 12 further comprising an air trap
whereby the air trap allows air to flow out of the heat
exchanger.
18. The fill adapter of claim 12 wherein the air trap comprising a
hydrophobic filter.
19. A method for atmospheric mitigation in an infusion pump
comprising: a pressure sensor sending data to a pump processor at a
predetermined interval; determining if the data exceeds an alarm
threshold; if the data exceeds a predetermined alarm threshold, the
processor indicating to the user to disconnect from a cannula;
determining if the data meets a pre-determined safe threshold; and
indicating to the user to re-connect to the cannula.
Description
CROSS REFERENCE TO RELATED APPLICATION(S)
[0001] The present application is a Continuation of U.S. patent
application Ser. No. 13/021,369, filed Feb. 4, 2011, now U.S. Pat.
No. 9,492,607, issued Nov. 15, 2016 and entitled Infusion Pump
Apparatus, Method and System (Attorney Docket No. 153), a
Non-provisional application which claims priority from U.S.
Provisional Patent Application Ser. No. 61/301,957, filed Feb. 5,
2010 and entitled Infusion Pump Apparatus, Method and System
(Attorney Docket No. H91), both of which are hereby incorporated
herein by reference in their entireties.
TECHNICAL FIELD
[0002] The present disclosure relates to medical devices and more
particularly, to an infusion pump apparatus, methods and
systems.
BACKGROUND INFORMATION
[0003] Many potentially valuable medicines or compounds, including
biologicals, are not orally active due to poor absorption, hepatic
metabolism or other pharmacokinetic factors. Additionally, some
therapeutic compounds, although they can be orally absorbed, are
sometimes required to be administered so often it is difficult for
a patient to maintain the desired schedule. In these cases,
parenteral delivery is often employed or could be employed.
[0004] Effective parenteral routes of drug delivery, as well as
other fluids and compounds, such as subcutaneous injection,
intramuscular injection, and intravenous (IV) administration
include puncture of the skin with a needle or stylet. Insulin is an
example of a therapeutic fluid that is self-injected by millions of
diabetic patients. Users of parenterally delivered drugs may
benefit from a wearable device that would automatically deliver
needed drugs/compounds over a period of time.
[0005] To this end, there have been efforts to design portable and
wearable devices for the controlled release of therapeutics. Such
devices are known to have a reservoir such as a cartridge, syringe,
or bag, and to be electronically controlled. These devices suffer
from a number of drawbacks including the malfunction rate. Reducing
the size, weight and cost of these devices is also an ongoing
challenge. Additionally, these devices often apply to the skin and
pose the challenge of frequent re-location for application.
SUMMARY
[0006] In accordance with one aspect of the present invention, a
system is disclosed. The system includes a fill adapter device
including a heat exchanger which includes a heating element and a
fluid pathway, the fluid pathway fluidly connected to a filling
needle input, whereby fluid enters the heat exchanger through the
filling needle input and flows through the fluid pathway and
whereby the fluid is heated by the heating element. The system also
includes a reservoir including a plunger and a plunger rod and a
filling needle configured to be removably attached to the
reservoir, wherein the fill adapter is configured to be attached to
a vial of fluid and wherein fluid from the vial flows through the
fluid pathway and is heated and loaded into the reservoir through
the filling needle.
[0007] Some embodiments of this aspect of the invention may include
one or more of the following. Wherein the system further includes a
pump to pump fluid into the fluid pathway at a predetermined rate.
Wherein the system further includes a check valve for metering
fluid into the fluid pathway whereby the rate of flow of fluid
through the heat exchanger is controller. Wherein the system
further includes a processor for controlling the heating of the
fluid according to one or more preprogrammed profiles. Wherein the
system further includes wherein the filling needle input is a
septum. Wherein the system further includes an air trap whereby the
air trap allows air to flow out of the heat exchanger. Wherein the
system further includes wherein the air trap comprising a
hydrophobic filter.
[0008] In accordance with one aspect of the present invention, a
fill adapter device is disclosed. The fill adapter device includes
a heat exchanger including a heating element and a fluid pathway,
the fluid pathway fluidly connected to a filling needle input and a
vial, whereby fluid from the vial enters the heat exchanger and
flows through the fluid pathway and whereby the fluid is heated by
the heating element.
[0009] Some embodiments of this aspect of the invention may include
one or more of the following. Wherein the device further includes a
pump to pump fluid into the fluid pathway at a predetermined rate.
Wherein the device further includes a check valve for metering
fluid into the fluid pathway whereby the rate of flow of fluid
through the heat exchanger is controller. Wherein the device
further includes a processor for controlling the heating of the
fluid according to one or more preprogrammed profiles. Wherein the
device further includes wherein the fill adapter is configured to
be attached to a vial of fluid. Wherein the device further includes
wherein the filling needle input is a septum. Wherein the device
further includes an air trap whereby the air trap allows air to
flow out of the heat exchanger. Wherein the device further includes
wherein the air trap comprising a hydrophobic filter.
[0010] In accordance with one aspect of the present invention, a
method for atmospheric mitigation in an infusion pump is disclosed.
The method includes a pressure sensor sending data to a pump
processor at a predetermined interval, determining if the data
exceeds an alarm threshold, if the data exceeds a predetermined
alarm threshold, the processor indicating to the user to disconnect
from a cannula, determining if the data meets a pre-determined safe
threshold, and indicating to the user to re-connect to the
cannula.
[0011] In accordance with one aspect of the present invention, an
infusion pump system is disclosed. The system includes a reservoir,
an active check valve located downstream from the reservoir and
upstream from a cannula, a passive check valve having a cracking
pressure located downstream from the reservoir, and a pump
processor, wherein the active check valve is opened by the pump
processor for scheduled pump deliveries, wherein when fluid
pressure overcomes the cracking pressure, the passive check valve
opens, and fluid flows from the reservoir and through the passive
check valve.
[0012] In accordance with one aspect of the present invention, an
infusion pump system is disclosed. The system includes a reservoir
and at least one valve downstream from the reservoir wherein at
least one valve is a pressure compensation valve having a cracking
pressure wherein a differential pressure related to the change a
altitude of the infusion pump cases the at least one valve to
open.
[0013] In accordance with one aspect of the present invention, a
method for atmospheric mitigation in an infusion pump is disclosed.
The method includes receiving information related to a scheduled
departure and a scheduled landing time, modifying the frequency of
processing data related to altitude based on the information,
determining, by comparing the information and the altimeter,
whether a change in schedule may be occurring, alerting a user of a
change of schedule, requesting updated schedule information, and
modifying the scheduled delivery of fluid based on the entered
schedule a altimeter data.
[0014] In accordance with one aspect of the present invention, an
infusion pump system is disclosed. The system includes a reservoir
comprising a plunger, at least one sensor for determining the
location of the plunger, and a processor configured to receive
information from the at least one sensor. The processor is
configured to modify the frequency of determination of the location
of the plunger and the processor is configured to determine the
volume of fluid either siphoned into or delivered out of a
reservoir and modify scheduled pump deliveries for a predetermined
amount of time.
[0015] In accordance with one aspect of the present invention, a
system for temperature compensation for an infusion pump is
disclosed. The system includes at least one temperature sensor and
at least one processor, the processor in communication with the
temperature sensor, wherein the processor determines a target
plunger position and, based at least upon communication from the
temperature sensor, modifies the target plunger position based on
the temperature sensed.
[0016] In accordance with one aspect of the present invention, a
system for pressure mitigation for an infusion pump is disclosed.
The system includes at least one pressure sensor; and a processor,
wherein the pressure sensor sends data to the processor and the
processor mitigates pressure changes if the pressure changes meet a
preprogrammed threshold.
[0017] These aspects of the invention are not meant to be exclusive
and other features, aspects, and advantages of the present
invention will be readily apparent to those of ordinary skill in
the art when read in conjunction with the appended claims and
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] These and other features and advantages of the present
invention will be better understood by reading the following
detailed description, taken together with the drawings wherein:
[0019] FIGS. 1A-1B are front and back isometric view of an
embodiment of an infusion pump;
[0020] FIGS. 1C-1E are side and front views of the infusion pump
assembly of FIG. 1;
[0021] FIG. 1F is a front isometric view of the infusion pump
assembly of FIG. 1;
[0022] FIG. 2 is an illustrative view of one embodiment of a remote
control assembly;
[0023] FIG. 3 is a diagrammatic view of the infusion pump assembly
of FIG. 1;
[0024] FIGS. 4A-4E depict a plurality of hook-and-loop fastener
configurations according to some embodiments;
[0025] FIG. 5 is an illustration of one embodiment of a holder;
[0026] FIG. 6 is an illustration of one embodiment of a user
wearing a holder;
[0027] FIG. 7 is an illustration of one embodiment of the back of a
holder;
[0028] FIG. 8 is an illustration of one embodiment of a vial with a
temperature gauge/label;
[0029] FIG. 9 is a flowchart of one embodiment of method for
atmospheric pressure determination and mitigation;
[0030] FIG. 10 is an illustration of one embodiment of a passive
and active check valve embodiment;
[0031] FIG. 11 is an illustration of a cross sectional view of one
embodiment of a fill adapter;
[0032] FIG. 12 is an illustration of a vial system for maintaining
a vacuum within a vial according to one embodiment;
[0033] FIG. 13 is an illustration of a vial apparatus according to
one embodiment; and
[0034] Appendix A is one embodiment of a micro check valve used in
some embodiments.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
Definitions
[0035] As used in this description and the accompanying claims, the
following terms shall have the meanings indicated, unless the
context otherwise requires: A "device" shall mean a medical device,
which includes, but is not limited to, an infusion pump and/or a
controller, i.e., a device for wireless control of another medical
device. In some embodiments, the word "device" is used
interchangeably with "pump", "infusion pump" and/or "controller"
and/or "Companion" and/or "remote controller device" and/or "remote
controller assembly".
[0036] A "Companion" shall mean a device for wireless control of
another medical device. In the exemplary embodiments, the Companion
may also include a glucose meter/strip reader.
[0037] An "input" of a device includes any mechanism by which a
user of the device or other operator/caregiver may control a
function of the device. User inputs may include mechanical
arrangements (e.g., switches, pushbuttons, jogwheel(s)), electrical
arrangements (e.g., a slider, touch screen), wireless interfaces
for communication with a remote controller (e.g., RF, infrared),
acoustic interfaces (e.g., with speech recognition), computer
network interfaces (e.g., USB port), and other types of
interfaces.
[0038] A "button" in the context of an input such as the so-called
"bolus button" discussed below may be any type of user input
capable of performing a desired function, and is not limited to a
pushbutton, a slider, switch, touch screen or a jog wheel.
[0039] An "alarm" includes any mechanism by which an alert may be
generated to a user or third party. Alarms may include audible
alarms (e.g., a speaker, a buzzer, a speech generator), visual
alarms (e.g., an LED, an LCD screen), tactile alarms (e.g., a
vibrating element), wireless signals (e.g., a wireless transmission
to a remote controller or caretaker), or other mechanism. Alarms
may be generated using multiple mechanisms simultaneously,
concurrently, or in a sequence, including redundant mechanisms
(e.g., two different audio alarms) or complementary mechanisms
(e.g., an audio alarm, a tactile alarm, and a wireless alarm).
[0040] "Fluid" shall mean a substance, a liquid for example, that
is capable of flowing through a flow line.
[0041] A "user" includes a person or animal who receives fluid from
a fluid delivery device, whether as part of a medical treatment or
otherwise, or a caregiver or third party involved in programming
the device or otherwise interacting with the device to infuse fluid
to another.
[0042] "Cannula" shall mean a disposable device capable of infusing
fluid to a user. A cannula as used herein may refer to a
traditional cannula or to a needle.
[0043] "Disposable" refers to a part, device, portion or other that
is intended to be used for a fixed duration of time, then discarded
and replaced.
[0044] "Reusable" refers to a portion that is intended to have an
open-ended duration of use.
[0045] "Acoustic volume measurement" shall mean quantitative
measurement of a relevant volume using acoustical techniques such
as those described in U.S. Pat. Nos. 5,349,852 and 5,641,892, which
are hereby incorporated by reference herein in their entireties, as
well as other techniques.
[0046] A "temperature sensor" includes any temperature
determination device/mechanism for measuring temperature and
communicating temperature information to a controller and/or to a
pump processor. The devices described herein may include one or
more temperature sensors for measuring such things as including,
but not limited to, one or more of the following: user skin
temperature, AVS temperature, ambient temperature, internal pump
temperature, plunger temperature, drive train temperature and fluid
temperatures.
[0047] An exemplary use of embodiments of the devices, methods and
systems described here is for the delivery of insulin to people
living with diabetes, but other uses include delivery of any fluid,
as described above. Fluids include analgesics to those in pain,
chemotherapy to cancer patients and enzymes to patients with
metabolic disorders. Various therapeutic fluids may include small
molecules, natural products, peptide, proteins, nucleic acids,
carbohydrates, nanoparticulate suspensions, and associated
pharmaceutically acceptable carrier molecules. Therapeutically
active molecules may be modified to improve stability in the device
(e.g., by pegylation of peptides or proteins). Although
illustrative embodiments herein describe drug-delivery
applications, embodiments may be used for other applications
including liquid dispensing of reagents for high throughput
analytical measurements such as lab-on-chip applications and
capillary chromatography. For purposes of description below, terms
"therapeutic", "insulin" or "fluid" are used interchangeably,
however, in other embodiments, any fluid, as described above, may
be used. Thus, the device and description included herein are not
limited to use with therapeutics.
[0048] Some embodiments of the fluid delivery device are adapted
for use by people living with diabetes and/or their caregivers.
Thus, in these embodiments, the devices, methods and systems work
to delivers insulin which supplements or replaces the action of the
person living with diabetes' (referred to as the user) pancreatic
islet beta cells. Embodiments adapted for insulin delivery seek to
mimic the action of the pancreas by providing both a basal level of
fluid delivery as well as bolus levels of delivery. Basal levels,
bolus levels and timing may be set by the user or a caregiver by
using a wireless handheld user interface or directly by using a
pump. Additionally, basal and/or bolus levels may be triggered or
adjusted in response to the output of a glucose meter, which in the
exemplary embodiments, is integral to the controller. In other
embodiments, the controller additionally includes a glucose
monitoring device which receives data from a blood glucose sensor.
In some embodiments, a bolus may be triggered by a user using a
designated button or other input means located on a device, i.e.,
on the controller and/or on an infusion pump. In still other
embodiments, the bolus or basal may be programmed or administered
through a user interface located either on the fluid delivery
device/infusion pump and/or on the controller.
[0049] With respect to the names given to screens and types of
screens, as well as proper names given to various features,
throughout various embodiments, these terms may vary.
[0050] The systems and methods described herein may be used to
control an infusion pump. For purposes of this description, the
various embodiments of the user interface and the infusion pump may
be described with reference to an insulin pump, or a pump which
infuses insulin. However, it should be understood that the user
interface may be on an infusion pump and/or on a controller.
Additionally, where the description pertains to an infusion pump
"screen", this "screen" may also appear on a controller, or may
appear on a controller in lieu of a pump.
[0051] Infusion pumps contemplated by this description include a
pump which may pump any fluid, including, but not limited to, a
therapeutic fluid, which includes, but is not limited to, insulin.
Thus, where this description describes the exemplary embodiment as
pertaining to insulin, this is meant merely for descriptive purpose
only as the device is not intended to be limited to insulin. Other
fluids are also contemplated. In some embodiments, the methods,
systems and devices described herein may be used in conjunction
with insulin "pens" and/or fluid delivery "pens", which are known
in the art.
[0052] The infusion pump may be any infusion pump, for example, but
not limited to, the pump devices shown and described with respect
to FIGS. 1A-1F and those incorporated herein by reference, and
include, but are not limited to, those incorporated herein by
reference. In the various exemplary embodiments, the infusion pump
is a syringe-pump, i.e., the fluid is pumped or delivered to the
user when a plunger advances in a syringe, pushing the fluid inside
the syringe into a cannula. Where the cannula is connected to a
user (i.e., the cannula is within the user's subcutaneous region)
the fluid is delivered subcutaneously to the user.
[0053] In the exemplary embodiment, the infusion pump includes
hardware for wireless RF communication with a controller. However,
in various embodiments, the infusion pump may be any infusion pump.
Referring to FIGS. 1A-1F and in some exemplary embodiments, the
infusion pump may include a display assembly 104, however, in other
exemplary embodiments, such as those shown in FIGS., the infusion
pump may not include a display assembly. In these embodiments, a
display assembly which may be similar to the one shown in FIGS. 1A,
1D and 1F, or may be larger or smaller, is included on a controller
or companion device. An embodiment of the controller or companion
device is shown in FIG. 2.
[0054] Referring to FIGS. 1A-1F, an embodiment of an infusion pump
assembly 100 that may be housed within enclosure assembly 102 is
shown. Infusion pump assembly 100 may include a display system 104
that may be visible through the enclosure assembly 102. One or more
switch assemblies/input devices 106, 108, 110 may be positioned
about various portions of the enclosure assembly 102. The enclosure
assembly 102 may include infusion port assembly 112 to which
cannula assembly 114 may be releasably coupled. A removable cover
assembly 116 may allow access to a power supply cavity 118 (shown
in phantom on FIG. 1D).
[0055] Referring to the infusion pump assemblies shown in FIG.
1A-1F, infusion pump assembly 100 may include processing logic (not
shown), which may be referred to as the pump processor, that
executes one or more processes that may be required for infusion
pump assembly 100 to operate properly. Processing logic may include
one or more microprocessors (not shown), one or more input/output
controllers (not shown), and cache memory devices (not shown). One
or more data buses and/or memory buses may be used to interconnect
processing logic with one or more subsystems. In some embodiments,
at least one of the subsystems shown in FIG. 3 is also included in
the embodiment of the infusion pump assembly 100 shown in FIGS.
1A-1F.
[0056] Referring now to FIGS. 1A-1F and FIG. 3, examples of the
subsystems interconnected with processing logic 400 may include but
are not limited to memory system 402, input system 404, display
system 406, vibration system 408, audio system 410 motor assembly
416, force sensor 412, temperature sensor (not shown) and
displacement detection device 418 (which may be referred to as a
device to determine and/or detect the distance the plunger has
moved with respect to the syringe barrel/syringe). Infusion pump
assembly 100 may include primary power supply 420 (e.g. a battery)
configured to be removable installable within power supply cavity
118 and to provide electrical power to at least a portion of
processing logic 400 and one or more of the subsystems (e.g.,
memory system 402, input system 404, display system 406, vibration
system 408, audio system 410, motor assembly 416, force sensor 412,
and displacement detection device 418).
[0057] Infusion pump assembly 100 may include reservoir assembly
430 configured to contain infusible fluid 422. In some embodiments,
reservoir assembly 430 may be a reservoir assembly similar to that
described in U.S. Pat. No. 7,498,563, issued Mar. 3, 2009 and
entitled Optical Displacement Sensor for Infusion Devices (Attorney
Docket No. D78), which is herein incorporated by reference in its
entirety, and/or as described in U.S. Pat. No. 7,306,578, issued
Dec. 11, 2007 and entitled Loading Mechanism for Infusion Pump
(Attorney Docket No. C54); PCT Application Serial No.
PCT/US2009/060158, filed Oct. 9, 2009 and entitled Infusion Pump
Assembly, now Publication No. WO 2010/042814, published Apr. 15,
2010 (Attorney Docket No. F51WO); and U.S. patent application Ser.
No. 12/249,882, filed Oct. 10, 2008 and entitled Infusion Pump
Assembly, now U.S. Publication No. US-2010-0094222, published Apr.
15, 2010 (Attorney Docket No. F51), all of which are hereby
incorporated herein in their entireties. In other embodiments, the
reservoir assembly may be any assembly in which fluid may be acted
upon such that at least a portion of the fluid may flow out of the
reservoir assembly, for example, the reservoir assembly, in various
embodiments, may include but is not limited to: a barrel with a
plunger, a barrel with a plunger connected to a plunger rod, a
cassette and/or a container at least partially constructed of a
flexible membrane.
[0058] Plunger assembly 424 may be configured to displace infusible
fluid 422 from reservoir assembly 430 through cannula assembly 450
(which may be coupled to infusion pump assembly 100 via infusion
port assembly 424) so that infusible fluid 422 may be delivered to
user 454. In this particular embodiment, plunger assembly 424 is
shown to be displaceable by partial nut assembly 426, which may
engage lead screw assembly 428 that may be rotatable by motor
assembly 416 in response to signals received from processing logic
400. In this particular embodiment, the combination of motor
assembly 416, plunger assembly 424, partial nut assembly 426, and
lead screw assembly 428 may form a pump assembly that effectuates
the dispensing of infusible fluid 422 contained within reservoir
assembly 430. An example of partial nut assembly 426 may include
but is not limited to a nut assembly that is configured to wrap
around lead screw assembly 426 by e.g., 30 degrees. In some
embodiments, the pump assembly may be similar to one described in
U.S. Pat. No. 7,306,578, issued Dec. 11, 2007 and entitled Loading
Mechanism for Infusion Pump (Attorney Docket No. C54); U.S. patent
application Ser. No. 12/249,882, filed Oct. 10, 2008 and entitled
Infusion Pump Assembly, now U.S. Publication No. US-2010-0094222,
published Apr. 15, 2010 (Attorney Docket No. F51); and U.S. patent
application Ser. No. 12/249,891, filed Oct. 10, 2008 and entitled
Infusion Pump Assembly, now U.S. Publication No. US-2009-0099523
published Apr. 16, 2009 (Attorney Docket No. G46), all of which are
herein incorporated by reference in their entireties.
User Interface
[0059] Throughout this description, screens may be referenced with
respect to the "pump" or "Companion" or "Controller". However, in
various embodiments, a similar screen or a similar method may be
accomplished on another device. For example, where the screen or
method is referenced with respect to the "pump", a similarly
functional screen or method may be used on the "Companion" or
"Controller" in other embodiments. As this description includes
embodiments related to both pumps having displays and pumps having
no displays, it should be evident that where the embodiment
includes an infusion pump without a display, any screens will be
visible on a Companion or Controller. Similarly, where a method
requires an interaction between the user and the pump, the
interaction may be accomplished via a switch assembly on the pump
where the pump is an infusion pump without a display.
[0060] Processing logic which in some embodiments, includes at
least one element as shown in described with respect to FIG. 3, is
used to receive inputs from a user or caregiver. The user or
caregiver uses one or more input devices or assemblies, including
but not limited to, one or more of the following: button/switch
assembly, slider assemblies, including, but not limited to,
capacitive sliders (which may include, for example, including but
not limited to any slider described in U.S. patent application Ser.
No. 11/999,268, filed Dec. 4, 2007 and entitled Medical Device
Including a Slider Assembly, now U.S. Publication No.
US-2008-0177900, published Jul. 24, 2008 (Attorney Docket No. F14),
which is hereby incorporated herein by reference in its entirety,
jog wheel and/or touch screen. The infusion device additionally
received inputs from internal systems, including but not limited to
occlusion detection process 438, confirmation process 440, volume
measurement technology (e.g., acoustic volume sensing). Using these
inputs, the infusion device produces outputs, for example
including, but not limited to, infusion fluid delivery to the user
or comments, alerts, alarms or warnings to the user. The inputs are
thus either directly from the user to the pump, directly from the
pump systems to the processing logic, or from another device, e.g.,
a remote controller device (described in more detail below), to the
pump. The user or caregiver interaction experience thus includes,
but is not limited to, one or more of the following: interaction
with a display (either on the infusion pump device itself or a
remote controller device or both), which includes but is not
limited to, reading/seeing text and/or graphics on a display,
direct interaction with a display, for example, through a touch
screen, interaction with one or more buttons, sliders, jog wheels,
one or more glucose strip readers, and sensing either through touch
sensation or audio, one or more vibration motors, and/or an audio
system. Thus, the term "user interface" is used to encompass all of
the systems and methods a user or caregiver interacts with the
infusion pump, to control the infusion pump.
[0061] Referring now to FIG. 2, in some embodiments of the infusion
pump system, the infusion pump may be remotely controlled using a
remote controller assembly 300, also referred to as a controller or
a companion. Remote control assembly 300 may include all, or a
portion of, the functionality of the infusion pump assembly shown
in FIGS. 1A-1F, itself. Thus, in some exemplary embodiments of the
above-described infusion pump assembly, the infusion pump assembly
(not shown, see FIGS. 1A-1F, amongst other FIGS.) may be configured
via remote control assembly 300. In these particular embodiments,
the infusion pump assembly may include telemetry circuitry (not
shown) that allows for communication (e.g., wired or wireless)
between the infusion pump assembly and e.g., remote control
assembly 300, thus allowing remote control assembly 300 to remotely
control infusion pump assembly 100. Remote control assembly 300
(which may also include telemetry circuitry (not shown) and may be
capable of communicating with infusion pump assembly) may include
display assembly 302 and an input assembly, which may include one
or more of the following: an input control device (such as jog
wheel 306, slider assembly 310, or another conventional mode for
input into a device), and switch assemblies 304, 308. Thus,
although remote control assembly 300 as shown in FIG. 2 includes
jog wheel 306 and slider assembly 310, some embodiments may include
only one of either jog wheel 306 or slider assembly 310, or another
conventional mode for input into a device. In embodiments having
jog wheel 306, jog wheel 306 may include a wheel, ring, knob, or
the like, that may be coupled to a rotary encoder, or other rotary
transducer, for providing a control signal based upon, at least in
part, movement of the wheel, ring, knob, or the like.
[0062] Remote control assembly 300 may include the ability to
pre-program basal rates, bolus alarms, delivery limitations, and
allow the user to view history and to establish user preferences.
Remote control assembly 300 may also include a glucose strip reader
312.
[0063] During use, remote control assembly 300 may provide
instructions to the infusion pump assembly via a wireless
communication channel established between remote control assembly
300 and the infusion pump assembly. Accordingly, the user may use
remote control assembly 300 to program/configure the infusion pump
assembly. Some or all of the communication between remote control
assembly 300 and the infusion pump assembly may be encrypted to
provide an enhanced level of security.
[0064] In the exemplary embodiments of the user interface, the user
interface may require user confirmation and user input. The
exemplary embodiments of the user interface are centered on
ensuring the user knows the effect of various interactions on the
pump. Many examples will be presented throughout this description
of the pump communicating the result of the user's actions to the
user. These features ensure the user understands their actions and
therefore, imparts greater safety onto the user. One such example
is throughout the exemplary embodiment of the user interface, where
the user presses the back button on a screen after a value has been
changed, the user interface displays the Cancel Changes
confirmation screen. If the user selects "Yes", the user interface
discards any pending changes, closes the confirmation screen and
goes back to the previous screen (i.e., the screen previous to the
screen where the user pressed the Back button). When the action
selection is "No", on the "Cancel Changes?" confirmation screen,
the user presses the enter button or other depending on the
embodiment, and the user interface closes the confirmation screen
and returns to the screen with pending changes. This feature
prevents the outcome where the user assumes the changes have been
implemented, but in fact, they have not been. Thus, this feature
prevents that circumstance and ensures the user understands that
the changes have not been implemented.
Temperature
[0065] In various embodiments of the infusion pump, the user may
wear the infusion pump either attached to a belt, attached to
another article or clothing or a garment such that the device is
worn on the body, or, in some embodiments, attached to an
undergarment, in a pocket or, in some embodiments, attached to the
skin of the user. The user generally wears the infusion pump as
close to twenty-four (24) hours a day as possible, and in some
cases, removing the device for short periods of time, for example,
but not limited to, during an MRI or other treatment that may
effect the device and/or while showering/bathing. Thus, during the
normal course of the user's wearing the infusion pump, the infusion
pump may be exposed to various temperatures, including, temperature
swings, which may include positive temperature swings and/or
negative temperature swings. These temperature swings may be the
result of the user stepping out of doors, into a cold room, into a
hot room and/or under a blanket or other warming agent.
[0066] The fluid contained in the reservoir while in the pump,
which, as discussed above, may include, but is not limited to
insulin, has a thermal expansion coefficient which may be referred
to as a general volumetric thermal expansion coefficient. Thus,
during a temperature swing/differential/change, whether positive or
negative, the fluid, or insulin, will expand or contract. Various
factors may contribute to the expansion or contraction of the fluid
including but not limited to the rate of change of the temperature.
Thus, in some embodiments, the amount of expansion or contraction
may be a function of the temperature.
[0067] Additionally, in various embodiments of the various
embodiments of the devices described, the components of the pumps
also have thermal expansion coefficients. These thermal expansion
coefficients may vary depending on the material. Thus, where the
various components are made from different materials, the thermal
expansion coefficients may vary.
[0068] In some embodiments, a change in temperature may affect a
thermal expansion or thermal contraction of the fluid and/or one or
more components of the infusion pump. For example, but not limited
to, an increase in temperature may cause an increase in the
diameter of the reservoir/syringe 430 (for illustration only,
please refer to FIG. 3). This may be because the relative thermal
expansion of the syringe compared with the fluid governs whether
fluid is delivered or pulled back. Thus, this in turn may cause any
fluid/insulin in the cannula 450 to flow backwards, towards the
reservoir 430. In this case, a volume of fluid/insulin is pulled
back into the reservoir. Thus, a subsequent request for a delivery
by processing logic 400 may only result in this retracted volume
being delivered to the user. Thus, a volume of fluid/insulin (the
retracted volume) has not been delivered to the user without
request or knowledge by the user. Another example includes
temperature decrease. In some embodiments, a temperature decrease
may cause the reservoir 430 to decrease in diameter, causing
fluid/insulin to flow to the cannula 450. Thus, an unintended bolus
volume is delivered to this user. In this case, fluid/insulin has
been delivered to the user without request or knowledge by the
user.
[0069] Thus, in the first example, the user may receive less
fluid/insulin than is required or requested and thus, may
experience hyperglycemia. In the second example, the user may
receive more fluid/insulin than is required or requested and thus,
may experience hypoglycemia. In either example, the user receives a
fluid/insulin volume that is not the same as the requested or
programmed therapy and is not notified of the disparity.
[0070] In these examples, the reservoir is assumed to be a
cylinder. Below is a mathematical model of the change in volume of
a cylinder (assuming a constant coefficient of linear expansion,
a). This is a model for explanation purposes. Additional
mathematical models may be determined to accommodate additional
assumptions, for example, a shape other than a cylinder, or a
syringe with a movable plunger.
.DELTA.V=V(3.alpha..DELTA.T+3.alpha..sup.2.DELTA.T.sup.2+.alpha..sup.3.D-
ELTA.T.sup.3) [EQ#1] [0071] Which may be simplified assuming
.alpha..DELTA.T<<1 to:
[0071] .DELTA. V V .apprxeq. 3 .alpha..DELTA. T [ EQ #2 ]
##EQU00001##
[0072] Thus, the volume change of a cylinder made from
polypropylene where the temperature changes from 30 C to 10 C for
polypropylene, which is a material with linear coefficient of
linear expansion
.alpha. = 86 .times. 10 - 6 cm cm K , ##EQU00002##
would be:
.DELTA. V V .apprxeq. 3 ( 86 .times. 10 - 6 cm cm K ) ( 20 K ) =
0.52 % [ EQ #3 ] ##EQU00003##
[0073] The change in specific volume for water between 30 C and 10
C is about 0.40%. The difference between the two (about 0.12%)
applied to a 3 cc syringe or reservoir would be about 3.6 .mu.L.
However, in addition, the syringe plunger may move in response to
the thermal expansion depending on the plunger material and the
relationship of the syringe in the pump (e.g., the design of the
syringe retention in the pump).
[0074] Therefore, there may be a desire to minimize the effect of
temperature on the delivery of fluid. Thus, it may be desired to
limit or minimize, and/or characterize, the thermal expansion of
the fluid and/or one or more of the components of the infusion
pump. The systems, methods and apparatus described to minimize the
effect of temperature on the thermal expansion of the fluid and/or
one of more of the components of the infusion pump may include one
or more of the following exemplary embodiments.
[0075] In some embodiments, selection of materials with predictable
and favorable thermal expansion coefficients may minimize the
potential under and over delivery of fluids as discussed above. In
some embodiments, the syringe material, for example, may be
selected to match the thermal expansion of the fluid. For example,
the linear expansion coefficient for water at about 20 C is
about:
68.9 .times. 10 - 6 cm cm K [ EQ #4 ] ##EQU00004##
[0076] Thus, the syringe material may be selected to have an
expansion coefficient close to this value. For example, a blend of
polycarbonate and acrylonitrile butadiene styrene (also referred to
as "ABS") could be used to match the thermal expansion coefficient
of the fluid. In some embodiments, other plastics, for example, but
not limited to, polycarbonate, may be close to the correct
expansion coefficient such that the volume delivered by the syringe
pump due to the expected temperature change is minimal and/or
acceptable. In some embodiments, the plastic or material selected
may be tailored to the slope of the thermal expansion of the
fluid.
[0077] In some embodiments, the material of the plunger and/or the
plunger rod may be selected to thermally differentially compensate
for the change in temperature. In some embodiments, the materials
for the syringe, plunger and plunger rod may be selected to
thermally differentially compensate for the change in temperature.
Also, or in addition to, in some embodiments, the material of one
or more components of the drive train, or any other component of
the infusion pump, may be selected to thermally differentially
compensate for the change in temperature.
[0078] In some embodiments, the materials for any one or more
infusion pump components may be selected to have an opposite
thermal coefficient, or a thermally compensating material to
minimize the thermal expansion effects of the temperature. For
example, in higher temperatures, where the infusion pumps syringe
expands, the flow of fluid may be negative. In some embodiments, at
least one component of the drive train may have a negative thermal
constant, thus, having the opposite thermal coefficient. Thus, upon
a temperature increase, the syringe does not experience a change in
volume.
[0079] In some embodiments, the use of a material which may undergo
a phase change during a temperature change event may minimize the
effect of the temperature differential/change on the infusion pump.
For example, in some embodiments, the plunger may include a
predetermined volume of wax, thus, as the temperature increases,
the length or position may increase due to the phase change of the
wax. Additional wax features may be added in some embodiments to
prevent flow. In some embodiments, a wax feature may be added to
move the plunger forward a (predetermined) distance such that the
resulting change in the volume is equal to the square root of the
diameter of the plunger. Thus, in some embodiments, the use of a
material which undergoes a phase change in response to
temperature/temperature change/differential may be used to
compensate for the change of volume of the syringe due to a
temperature change. In some embodiments, the material which
undergoes a phase change in response to a temperature change may
absorb the energy of the thermal differential, thus, for example,
where the temperature is increasing, rather than rising the
temperature of the infusion pump, the wax, or other phase change
material, may melt the wax/phase change material, thus, acting as
an energy sink and absorbing the heat.
[0080] In some embodiments, the syringe may be constrained in such
a way that a change in temperature may cause the plunger to be
advanced or withdrawn to compensate for the volume change of the
syringe. For example, in some embodiments, the syringe may be held
in a metal case, the metals that may be used include but are not
limited to, steel, aluminum, and/or any metal with a low
coefficient of thermal expansion, which may include, but is not
limited to, FeNi36, also known as INVAR.RTM.. The plunger may be
made from a material that has a high coefficient of thermal
expansion. Thus, in this example, a decrease in temperature may
cause the syringe plunger to be withdrawn as the diameter of the
syringe barrel is decreasing. Thus, balancing these effects, the
change in the total volume may be minimized.
Characterization and Controls Compensation
[0081] In some embodiments, characterizing the effect of a change
in temperature on the volume of fluid pumped by the infusion device
may be completed. In this embodiment, the pump may be subjected to
temperature variation (i.e., both positive and negative) and the
corresponding response by the infusion pump may be recorded. The
characterization may include, but is not limited to, varying rates
of change (i.e., 1 degree Celsius per minute, and whether positive
and negative, etc), total temperature variation (e.g., 10 degrees
Celsius, 5 degrees Celsius, etc), and/or position of syringe
plunger.
[0082] The infusion pump may include one or more devices and/or
components and/or systems to determine the temperature. In some
embodiments, the infusion pump may include one or more thermistors
or other temperature sensors to determine the temperature. However,
in other embodiments, various methods and/or devices and/or systems
to determine the temperature, either directly or indirectly, may be
used, including, but not limited to, one or more of the following:
at least one resistance temperature device (RTD) and/or at least
one non-contact infrared device (non-contact IR). The location of
the one or more thermistors and/or temperature determination
devices may vary. The locations of one of more of the thermistors
and/or temperature determination devices may include, but is not
limited to, the drive screw, any location on the drive train, on
the syringe barrel, including but not limited to, printed on the
syringe barrel, the plunger and/or, the printed circuit board. In
various embodiments, the one or more thermistor(s) and/or
temperature determination devices location may be any where away
from the heat sources that would render a potentially false
reading. In some embodiments, the one or more thermistors may
determine the temperature of one or more locations, including, but
not limited to, inside of the syringe, the outside of the syringe,
the inside of the pump, and/or the outside of the pump. Various
controls may be determined based on a temperature model in any one
or more of these locations. Thus, in some embodiments, the
characterization may be made by taking temperature readings both
within the syringe and outside of the syringe. In other
embodiments, the characterization may be performed by taking
temperature readings from outside the pump and inside the pump. In
the various embodiments, the one or more thermistors and/or
temperature determination devices are preferably placed in the same
location on the pump for use by the user as they were during the
characterization.
[0083] In some embodiments, the characterization may be completed
by measuring the volume of fluid delivered as a function of
temperature. In some embodiments, this may be accomplished by using
a thermal chamber and an infusion set/cannula connected to the
reservoir/syringe delivering fluid to a precision scale. However,
in other embodiments, this may completed by using a thermal chamber
and an infusion set/cannula connected to the reservoir/syringe
delivering fluid, and following, determining the position of the
plunger inside the reservoir to determine the total volume of fluid
delivered.
[0084] In some embodiments, in practice, the temperature of the
pump (in one or more locations and/or taken by one or more
thermistors) may be measured and the target position of the plunger
may vary as a function of temperature to compensate for the thermal
expansion of the syringe and/or the plunger. The thermal expansion
reading may be determined by referencing the characterization data,
as discussed above. Thus, in some embodiments, the target position
may be modified based on a look-up table or function approximation
of the volume change of the syringe with temperature.
[0085] In some embodiments, the infusion pump delivers fluid either
as a basal or a bolus delivery, and/or a variety thereof. The basal
delivery is a programmed rate or volume per hour. The infusion pump
delivers a volume of fluid at preset intervals for preset durations
of time. The infusion pump may also deliver bolus volumes. A bolus
is a requested volume of fluid delivered immediately, i.e., at the
time the request is made. One embodiment of the bolus and basal
delivery methods is described in PCT Application Serial No.
PCT/US2009/060158, filed Oct. 9, 2009 and entitled Infusion Pump
Assembly, now Publication No. WO 2010/042814, published Apr. 15,
2010 (Attorney Docket No. F51WO); and U.S. patent application Ser.
No. 12/249,882, filed Oct. 10, 2008 and entitled Infusion Pump
Assembly, now U.S. Publication No. US-2010-0094222, published Apr.
15, 2010 and entitled Infusion Pump Assembly (Attorney Docket No.
F51), both of which are hereby incorporated herein by reference in
their entireties. Further, in some embodiments, for example, in the
embodiment described in U.S. Pat. No. 7,498,563, issued Mar. 3,
2009 and entitled Optical Displacement Sensor for Infusion Devices
(Attorney Docket No. D78), which is herein incorporated by
reference in its entirety, the infusion pump may determine the
distance the plunger must move to deliver a volume of fluid, e.g.,
a basal volume or a bolus volume. Thus, in some embodiments of the
infusion pump system, the infusion pump may confirm the distance
the plunger moved during a delivery using an optical displacement
sensor. In some embodiments, the infusion pump determines the
number of motor encoder counts per delivery and confirms movements
of the plunger.
[0086] However, in various embodiments, the delivery method
includes a determination of the distance the plunger should move
(which may be referred to as the target plunger position) to
deliver the desired/target volume. As discussed above, this may be
done by determining the number of motor encoder steps, and in other
embodiments, may be another method. Regardless, the infusion pump
makes a determination of plunger distance movement.
[0087] One example of the characterization and controls
compensation method is as follows. The first step may be to
characterize the volume delivered as the temperature changes. This
volume may be a function of the amount of fluid contained in the
syringe, call this V, and, due to variations in the thermal
expansion properties of plastics and liquids/fluids, also, a
function of the temperature, call this T. A function, .beta.(T),
may be found empirically that related the volume change to the
temperature change.
.beta. ( T ) = 1 V .DELTA. V .DELTA. T [ EQ #5 ] ##EQU00005##
[0088] The coefficient .beta.(T) may be approximated as a constant,
found as a function of temperature (as shown above) or possible
found as a function of both temperature and plunger position
.beta.(T,x).
[0089] Next, the target plunger position may be determined and
adjusted. The target position, x, may be adjusted based on the
following formula:
.DELTA. x = .beta. ( T ) V .pi. 4 D 2 .DELTA. T [ EQ #6 ]
##EQU00006##
[0090] Where D is the plunger diameter. If we substitute in
V = .pi. 4 D 2 x ##EQU00007##
(assuming that x=0 where the plunger has reached the end of travel
and displaced all of the fluid in the syringe) then the
relationship may be simplified to:
.DELTA.x=.beta.(T).times..DELTA.T [EQ#7]
[0091] In various embodiments, this correction may be performed in
different ways, including, but not limited to, the following. In
some embodiments, the correction may be done by delivering on an
interval which may be more frequent than the basal delivery
interval, which may be, but is not limited to, one delivery every
e.g., 3 minutes, but in other embodiments, may be more frequent or
less frequent. Further, the position of the syringe may be adjusted
based on the temperature change, maintaining a zero net volume
delivered between regular deliveries, e.g., basal and/or bolus
deliveries. In some embodiments, this may be used for low basal
rates, where the thermally driven volume may exceed the regularly
scheduled basal delivery. This may, however, in some embodiments,
require reversing the syringe direction to prevent delivery.
[0092] Another embodiment may include applying the correction when
the fluid/insulin is scheduled for delivery. Thus, the target
plunger position may be corrected based on the measured temperature
change and estimated thermally-driven volume delivery. In some of
these embodiments, the correction may be limited such that the
plunger may only be driven in one direction.
[0093] In some embodiments, modeling may vary, and an assumption
may be made with respect to both length and diameter of the
syringe. In addition, assumption may be made regarding the effect
of temperature on the thermal expansion coefficient of one or more
components of the infusion pump, including, but not limited to, the
drive train, plunger, plunger rod, infusion pump housing, and
cannula.
[0094] In some embodiments, adjusting the plunger target may
include adjusting the target so that it is closer to the exit of
the syringe, or further away from the exit of the syringe. In some
embodiments, the plunger advancement may be modified. In other
embodiments, the plunger may be driven backwards to compensate for
temperature. However, in some embodiments, depending on the
infusion pump, it may be desired to limit adjustment to closer to
the exit of the syringe. This may be due to the potential for
backlash.
[0095] In some embodiments, a temperature dependant basal rate may
be preprogrammed to the pump for temperature compensation. In these
examples, the pump processor receives data from at least one
temperature sensor. If the temperature data indicates that the
temperature is such, or that the rate of change of temperature is
such, that an adjustment should be made, the processor may signal
to alter the preprogrammed basal rate. In some embodiments, this
alteration may be either an additional or a decrease of the basal
rate by a preset percentage, for example, an increase of 30% or a
decrease of 15%. Of course, these are only examples, and in these
embodiments, the preset alterations may be determined to be
different from those stated.
[0096] In some embodiments, the infusion pump may include at least
one temperature sensor and at least one optical sensor. In some
embodiments, the optical sensor may be used to determine that the
plunger advanced. In some embodiments, the distance of advancement
may also be determined. In some embodiments, a small reflective
optical sensor (hereinafter "optical sensor") that fits into the
form factor of the infusion pump hardware is used. The optical
sensor has a sensing range that overlaps with the plunger
displacements. In the exemplary embodiment any optical sensor may
be used, including, but not limited to a Sharp GP2S60, manufactured
by Sharp Electronics Corporation which is a U.S. subsidiary of
Sharp Corporation of Osaka, Japan. This optical sensor contains an
infra red emitting diode and infra red sensing detector in a single
package. Light from the emitter is unfocused and bounces off the
sensing surface, some of which makes it back to the detector
resulting in the sensed intensity of light that varies as a
function of distance/angle to the reflector. In some embodiments,
the sensor is placed such that the reflective surface is the
plunger.
[0097] In some embodiments, an optical sensor may be used to
determine the level of fluid in the syringe/reservoir. This
information may be used to determine whether the plunger rod has
advanced. Together with the temperature sensor information, this
may provide added data/information to determine a temperature
dependant change.
[0098] In some embodiments of the infusion pump system, including
those embodiments disclosed and described in U.S. Pat. No.
7,498,563, issued Mar. 3, 2009 and entitled Optical Displacement
Sensor for Infusion Devices (Attorney Docket No. D78); PCT
Application Serial No. PCT/US2009/060158, filed Oct. 9, 2009 and
entitled Infusion Pump Assembly, now Publication No. WO
2010/042814, published Apr. 15, 2010 (Attorney Docket No. F51WO);
and U.S. patent application Ser. No. 12/249,882, filed Oct. 10,
2008 and entitled Infusion Pump Assembly, now U.S. Publication No.
US-2010-0094222, published Apr. 15, 2010 and entitled Infusion Pump
Assembly (Attorney Docket No. F51), all of which are hereby
incorporated herein by reference in their entireties, the infusion
pump may include an optical displacement sensor. This sensor may be
used to determine whether the plunger rod has advanced, either
forward or backwards, and the distance of the advancement. Using
this displacement information, together with the information from
the one or more temperature sensors, the effect of the temperature
change on the plunger may be determined. In turn, this
determination may increase the accuracy of controls used to
compensate for a temperature change. This may include, but is not
limited to, decreasing the amount of fluid delivered due to a
sensed forward movement and/or increasing the amount of fluid
delivered due to a sensed backwards movement. In either case, the
increase and/or decease of the basal rate and/or amount and/or the
amount of bolus (for example, by a percentage of the amount
intended) is by a predetermined amount and for a predetermined
time.
[0099] In some embodiments, the infusion pump system may include a
system and/or method for adjusting the basal rate and/or bolus
amount based on a temperature change. Thus, in various embodiments,
where the system determines that a threshold temperature change,
either up or down, has occurred, the system may automatically,
and/or by request and/or confirmation by the user, enter a mode
having a limited period, e.g., a flat pre-set limited time period,
e.g., 20 minutes, and/or in some embodiments, the mode may continue
until the temperature change threshold is not longer applicable. In
some embodiments, where, for example, a decreasing temperature
gradient is a primary concern, the infusion pump processor may be
pre-programmed with a "decreasing gradient" mode, and the infusion
pump may purposefully under deliver in this mode, i.e., an
automatic percentage decrease in the basal rate, and, in some
embodiments, also, the bolus, may be instituted to compensate for a
predicated additional delivery of fluid. As discussed above,
determining the percentage change of insulin delivery may depend on
the characterization of the infusion pump.
[0100] Following, in some embodiments, where, for example,
increasing temperature gradient is the primary concern, the
infusion pump processor may be pre-programmed with a "increasing
temperature gradient" mode, and the infusion pump may purposefully
over deliver, i.e., an automatic percentage increase in the basal
rate, and, in some embodiments, also the bolus, may be instituted
to compensate for the predicated decrease in delivery of fluid. As
discussed above, determining the percentage change may depend on
the characterization of the infusion pump.
Closed Loop Temperature Compensation
[0101] For the purposes of this description, the term "advanced"
refers to the movement of a plunger within a syringe or reservoir
body. Advancement is not limited to movement in a particular
direction. The syringe has an exit end, which is the end of the
syringe in which fluid moves outward from the syringe.
[0102] In some embodiments, the system may include one or more
devices and/or sensors to determine the effect of the temperature
on the syringe/plunger and/or the pumping of fluid, either towards
the user/cannula or away from the user/cannula. These devices
and/or sensors may include, but are not limited to, one or more
flow sensors, one more occlusion devices and/or one or more binary
valves, and/or one or more strain beams or sensors and/or one or
more optical sensors and/or one or more temperature sensors and/or
one or more ultrasonic range sensors and/or one or more
potentiometers and/or one or more rotor encoders and/or one or more
linear encoders.
[0103] With respect to optical sensors, in some embodiments, the
infusion pump may include at least one temperature sensor and at
least one optical sensor. In some embodiments, the optical sensor
may be used to determine that the plunger advanced. In some
embodiments, the distance of advancement may also be determined. In
some embodiments, a small reflective optical sensor (hereinafter
"optical sensor") that fits into the form factor of the infusion
pump hardware is used. In various embodiments, the optical sensor
has a sensing range that overlaps with the plunger displacements.
In various embodiments any optical sensor may be used, including,
but not limited to one or more of the following: Sharp GP2S60,
Sharp GP2S700 and Sharp GP2A240LC, all of which are manufactured by
Sharp Electronics Corporation which is a U.S. subsidiary of Sharp
Corporation of Osaka, Japan. This optical sensor contains an infra
red emitting diode and infra red sensing detector in a single
package. Light from the emitter is unfocused and bounces off the
sensing surface, some of which makes it back to the detector
resulting in the sensed intensity of light that varies as a
function of distance/angle to the reflector. In some embodiments,
the sensor is placed such that the reflective surface is the
plunger.
[0104] In some embodiments, an optical sensor may be used to
determine the level of fluid in the syringe/reservoir. This
information may be used to determine whether the plunger rod has
advanced. Together with the temperature sensor information, this
may provide added data/information to determine a temperature
dependant change.
[0105] In some embodiments of the infusion pump system, the
infusion pump may include an optical displacement sensor. This
sensor may be used to determine whether the plunger rod has
advanced, either forward (towards the syringe exit) or backwards
(away from the syringe exit), and the distance of the advancement.
Using this displacement information, together with the information
from the one or more temperature sensors, the effect of the
temperature change on the plunger may be determined. In turn, this
determination may increase the accuracy of controls used to
compensate for a temperature change. This may include, but is not
limited to, decreasing the amount of fluid delivered (i.e.,
decreasing the volume of fluid that was scheduled to be delivered,
i.e., basal rate, or requested to be delivered, i.e., bolus amount)
to a sensed forward movement and/or increasing the amount of fluid
delivered due to a sensed backwards movement.
[0106] In some embodiments, the infusion pump may include an exit
valve and/or an occluder. Thus, in these embodiments, the infusion
pump includes at least one device to prevent the delivery of fluid
either from the syringe to the cannula and/or from the cannula to
the user. In some embodiments, the device is activated when the at
least one temperature sensor sends a signal to the processor and
the processor determines that the temperature change meets a
threshold, i.e., that the temperature change is large enough to
effect a change in delivery due to temperature. In some
embodiments, this may activate the occluder and/or exit valve,
preventing fluid from flowing into or out of the syringe and/or the
cannula. In some embodiments, the occluder and/or exit valve device
is deactivated when the at least one temperature sensor sends a
signal to the processor and the processor determines that the
temperature change no longer meets a threshold, i.e., that the
temperature change is no longer large enough to effect a change in
delivery due to temperature. In some embodiments, this may
deactivate the occluder and/or exit valve, allowing fluid to flow
out of the syringe and/or to the cannula and/or to the user. Again,
as discussed above, in some embodiments, the plunger target may be
adjusted in response to the information from one or more
temperature sensors.
[0107] In some embodiments, the occluder/exit valve may be closed
during the interval when the infusion pump is not actively
delivering fluid so as to prevent inadvertent fluid flow in or out
of the syringe/reservoir due to a change in temperature. During the
time when the infusion pump is not actively delivering fluid, the
at least one temperature sensor may continue to send signals to the
processor indicating temperature. This information may be used by
the control system to determine whether and how to modify the "next
delivery" of fluid, i.e., the next plunger target. Thus, when the
"next delivery" is made, the occluder/exit valve may open and the
fluid is delivered.
[0108] Thus, in these embodiments, the occluder/exit valve may act
primarily to prevent spontaneous unintended fluid flow that may be
caused by temperature change. The control system may adjust the
volume delivery, i.e., plunger target, based on the temperature
change such that the volume of delivered fluid compensates for the
temperature change.
[0109] In some embodiments, the infusion pump may include a
compliant component. In some embodiments, the compliant component
may allow the difference in volume change in the syringe/reservoir
while maintaining a pressure constant. Thus, in these embodiments,
controller compensation may not be necessary to compensate for
temperature change when the occluder/exit valve is open as there
would not be a pressure build up from a change in temperature.
[0110] In some embodiments, once a threshold temperature change has
been determined, the occluder/exit valve may be closed and the
plunger rod may be allowed to float, i.e., the plunger rod may
become disengaged with the drive train. A change in pressure would
thus allow the plunger to float and find equilibrium, thus
adjusting without the need for controller compensation in response
to a temperature change.
[0111] In some embodiments, the infusion pump may include at least
one flow sensor, including, but not limited to, a flow sensor
positioned in the exit fluid path. The flow sensor may detect the
flow of fluid. This information may be correlated with delivery
instructions and a determination may be made whether the fluid
delivered was requested and/or a proper delivery. In some
embodiments, where flow is detected and it is determined that the
fluid delivered was not requested and/or not a proper delivery, the
occluder and/or exit valve may be closed. Thus, in some
embodiments, a flow sensor may determine fluid flow, either inward
or outward, and where this is not an expect event, the infusion
pump may activate at least one mechanism, including, but not
limited to, an occluder and/or a valve to prevent the continued
flow of fluid. Additionally, the flow information may be used to
determine the amount or volume of fluid that has been delivered or
has flowed inward and this information may be used to alter the
plunger target during the next scheduled or requested delivery
(e.g., basal or bolus), or, in some embodiments, may be used to
alter the delivery schedule. In some embodiments, this may be
completed without user interaction. In some embodiments, an alert
may be sent to the user and the user must accept the proposed
course or action to alleviate the under or over delivery of
fluid.
[0112] In some embodiments, the infusion pump may include one or
more optical sensors. These sensors may be placed in the infusion
pump to determine the level of fluid in the syringe/reservoir. The
one or more optical sensors may determine the level of fluid before
the processor signals the drive train to advance the plunger and
after. Thus, the volume difference may be determined before and
after the plunger is advanced. However, the at least one optical
sensor may, in some embodiments, collect data a preset intervals,
regardless or whether the drive train has been activated. Thus, the
at least one optical sensor may collect information to determine
when and whether the plunger has advances and/or when and whether
fluid has been delivered or pulled in. Thus, the at least one
optical sensor may collect data for the processor to determine when
a non-requested delivery event may have occurred. The processor may
correlate this information with the at least one temperature sensor
and thereby determine whether the infusion pump is experiencing a
temperature related effect. In some embodiments, the processor may
alert the user. In some embodiments, the information may be used to
instigate a control algorithm to compensate for the temperature
change effect using, for example, but not limited to, the various
embodiments discussed herein.
[0113] In some embodiments, a strain beam may be used to identify a
plunger moving away from the exit of the syringe. In these
embodiments, the strain beam may be positioned relative to the
plunger rod such that where the plunger rod begins to move away
from the syringe exit, the strain beam will sense the strain. In
some embodiments of the infusion pump system, the infusion pump
includes a strain beam that may be used to detect and/or identify
occlusions. The strain beam and methods may be, in some
embodiments, similar to those described in U.S. patent application
Ser. No. 12/249,882, filed Oct. 10, 2008 and entitled Infusion Pump
Assembly, now U.S. Publication No. US-2010-0094222, published Apr.
15, 2010 (Attorney Docket No. F51); and PCT Application Serial No.
PCT/US2009/060158, filed Oct. 9, 2009 and entitled Infusion Pump
Assembly, now Publication No. WO 2010/042814, published Apr. 15,
2010 (Attorney Docket No. F51 WO), which are hereby incorporated
herein by reference in their entireties. However, together with the
at least one temperature sensor, a strain beam may determine
whether a particular temperature change has resulted in plunger
movement. Where plunger movement is detected due to a temperature
change, the infusion pump may alert the user. In some embodiments,
the system may correlate a change in strain with a change in
temperature.
Temperature Maintenance
[0114] As discussed above, there may be a desire to maintain the
temperature of an infusion pump to avoid any consequences from a
temperature change. In some embodiments, to minimize or prevent the
above-described effects of temperature changes on the infusion pump
and delivery of fluid, one or more various apparatus and/or systems
may be employed to maintain the temperature of the infusion
pump.
[0115] In some embodiments, the infusion pump includes a heater
device. The heater device may receive instructions from the
processor. The heater device may be located anywhere in or on the
infusion pump, however, in some embodiments, the heater device is
located within the infusion pump housing. In some embodiments, the
heater device is powered by a power source or battery inside the
infusion pump. However, in some embodiments, the power source may
be outside the infusion pump.
[0116] The heater source may be any heating source desired,
however, in the exemplary embodiment, the heating source may be a
KAPTON.RTM. (Polyimide Film) Heater kit, part number
KH-KIT-EFH-15001 and available from Omega.com.RTM.. In some
embodiments, at least one temperature sensor is located in or on
the infusion pump. The at least one temperature sensor communicates
information to the processor. Based on the temperature sensor data,
the processor may act as a thermostat and power the heater source
to maintain the temperature in the infusion pump at a desired
temperature. In some embodiments, the desired temperature may be
between 15 and 30 degrees Celsius, but in other embodiments, the
maintenance temperature may be different. In some embodiments, it
may be desirable to maintain the temperature at the higher end.
[0117] In some embodiments the syringe/reservoir may be contained
in a metal case in the infusion pump. The metal case may increase
the conduction of heat between the heater element and the
syringe/reservoir.
[0118] In some embodiments, the at least one heater element may be
located in one or more locations inside the infusion pump and one
or more of these locations may be selected to maintain the
temperature of one or more components of the infusion pump,
including, but not limited to, the syringe, fluid, plunger,
housing, plunger rod and/or the drive train.
[0119] In some embodiments, the at least one heater elements may
additionally increase the power source and/or battery life in the
infusion pump. Maintaining the temperature at or about 35 degrees
Celsius may be beneficial to battery life and/or performance.
[0120] In some embodiments, it may be desirable to utilize the
user's body as a heat sink, wearing the infusion pump close to the
user's skin. This may be accomplished using various devices and
apparatus, including but not limited to one or more of the
following.
[0121] A hook and loop system fastener system, for example, but not
limited to one offered by VELCRO.RTM. USA Inc. of Manchester, N.H.,
may be utilized to allow for easy attachment/removal of an infusion
pump from the user. Accordingly, an adhesive patch may be attached
to the skin of the user and may include an outward facing hook or
loop surface. Additionally, a surface of infusion pump 114 may
include a complementary hook or loop surface. Depending upon the
separation resistance of the particular type of hook and loop
fastener system employed, it may be possible for the strength of
the hook and loop connection to be stronger than the strength of
the adhesive to skin connection. Accordingly, various hook and loop
surface patterns may be utilized to regulate the strength of the
hook and loop connection.
[0122] Referring also to FIGS. 4A-4E, five examples of such hook
and loop surface patterns are shown. Assume for illustrative
purposes that one surface of infusion pump housing is covered in a
"loop" material. Accordingly, the strength of the hook and loop
connection may be regulated by varying the pattern (i.e., amount)
of the "hook" material present on the surface of adhesive patch.
Examples of such patterns may include but are not limited to: a
singular outer circle 220 of "hook" material (as shown in FIG. 4A);
a plurality of concentric circles 222, 224 of "hook" material (as
shown in FIG. 4B); a plurality of radial spokes 226 of "hook"
material (as shown in FIG. 4C); a plurality of radial spokes 228 of
"hook" material in combination with a single outer circle 230 of
"hook" material (as shown in FIG. 4D); and a plurality of radial
spokes 232 of "hook" material in combination with a plurality of
concentric circles 234, 236 of "hook" material (as shown in FIG.
4E).
[0123] In another embodiment, a holder, pouch, sack, container or
other type of housing (generally referred to as a "holder") may be
sized to accommodate an infusion pump. In some embodiments, the
holder may be constructed to include multiple layers including but
not limited to, one or more insulating layers. In some embodiments,
one or more of the layers may include a fabric that when wetted and
refrigerated or frozen, the layer provides a cooling effect. This
layer may be desired in warmer climates or in situations where the
user's infusion pump may be exposed to the sun or a warm
environment. In some embodiments, the one or more layers of
material may be highly absorbent material. In some embodiments, the
holder may include one or more canisters of isopropyl alcohol which
may, when deployed, be absorbed into the highly absorbent material
of the holder and provide evaporative cooling to the infusion pump.
In various embodiments, the holder may include alternative and/or
additional methods, systems and/or devices for cooling the infusion
pump.
[0124] In some embodiments, the holder may include one or more
temperature measurement devices and/or temperature sensors that may
transmit information to the infusion pump and/or a controller. The
one or more temperature sensors may communicate the temperature of
the holder and either deploy the one or more canisters of alcohol
and or alert the infusion pump/user/controller and/or turn o the
heating source, based on the temperature sensor. In some
embodiments, the heating and/or cooling may be triggered by
reaching a threshold change in temperature. Thus, in some
embodiments, the holder may provide for a closed-loop system for
maintaining the temperature for the infusion pump.
[0125] Referring now to FIG. 5, some embodiments of the holder 500
include an outside layer 502, an inside layer 504 and an inner
pocket 506. The pocket 506 may include additional cushion or
insulation to both protect the infusion pump from outside forces
and/or temperature change. The holder 500 may include a fastener
along the front, top or the side. In some embodiments, the holder
500 may include the holder may include a pull down flap (not shown)
on the front to expose the screen and/or input assemblies (e.g.,
including but not limited to buttons, sliders, and/or jog wheels).
In some embodiments, the flap may be secured closed using a
hook-and-loop system. In other embodiments, the flap may be secured
using any other fastener system including, but not limited to,
snaps, buttons, magnetic closures and zippers.
[0126] In some embodiments, the holder 500 may be attached to a
strap 508 designed to be attached to the user (see FIG. 6 for
example). However, in various embodiments, the strap 508 may be
elastic and/or adjustable and may include at least one closure
device. Although shown in FIG. 6 as being worn about the mid
section of a user 510, the holder 500 may be worn anywhere the user
desires.
[0127] Referring now to FIG. 7, an embodiment of the back of the
holder 500 is shown. In some embodiments, the holder may include a
clip 512 which may be referred to as a "belt-clip" or another type
of clip configured such that it securely and removably fits over a
belt, handle, piece of clothing or other. In some embodiments, the
holder 500 may additionally include an opening 514 for tubing 516
to fit through. In some embodiments, the infusion pump (not shown)
may be contained inside the holder 500 and the holder worn close to
the insertion site (not shown) on the user such that minimal tubing
516 is exposed to the outside temperature. Thus, embodiments of the
holder 500 including an opening 514 for tubing may be beneficial
for maintaining the temperature of the tubing 516 and/or the fluid
in the tubing.
[0128] In some embodiments, a plastic material for example, a Press
n' Seal, or another material of similar behavior, may be used to
attach and maintain the infusion pump against the user's body. In
other embodiments, a cuff or band fitted against the leg,
midsection or arm, for example, of a user may include a pouch for
the infusion pump. In other embodiments, the infusion pump may be
maintained in position against the skin through inner pockets, bra
pockets, etc.
[0129] Various embodiments are described herein for both utilizing
the user's body heat and/or a heating element to maintain the
temperature of the infusion pump. However, additional devices and
apparatus are within the scope of the invention. Further, various
methods, systems and apparatus for maintaining the temperature of
an infusion pump may include at least one temperature sensor.
Insulin Temperature
[0130] Described herein are various methods, systems, devices
and/or apparatus for maintaining the temperature of an infusion
pump. Inherent in at least some of these embodiments is the
maintenance of the infusible fluid/insulin temperature. It is well
know that manufacturers of insulin recommend that the temperature
of insulin not exceed a high and a low temperature. Additionally,
it may be beneficial to maintain fast-acting (e.g., HUMALOG.RTM.,
NOVOLOG.RTM.) at room/ambient temperature (e.g., between 59 and 86
degrees Fahrenheit) once the vial has been used, i.e., the
manufacturer recommends storing insulin in a refrigerated area,
e.g., between 36 and 46 degrees Fahrenheit, until the vial is used.
From that point on, it is recommended that the vial be stored at
room temperature.
[0131] As insulin may be less effective or not effective once it
has reached a non-recommended temperature, it may be beneficial for
a user to know whether the insulin has been properly stored,
whether while in transit, in the refrigerator or while in use.
[0132] Referring to FIG. 8, in one embodiment, a stick-on
temperature gauge 520 may be placed on a vial 522 of fluid, and in
some embodiments, on a vial of insulin. The gauge may tell the user
the current temperature of the vial. In some embodiments, the
temperature may be indicated as various shades of red and blue,
indicating various temperatures towards the high and low range. In
some embodiments, once the temperature has reached either the
maximum or minimum temperature (which is predetermined and may, in
some embodiments, be 35 and 87 Fahrenheit respectively), the gauge
becomes non-reversible, thus indicating instantly to the user that
the insulin has reached either a maximum or minimum
temperature.
[0133] Any stick-on temperature gauge may be used including a
non-reversible temperature label such as a Non-Reversible
Temperature Labels, 3 Temperature Ranges, part number TL-3
available from Omega.com.RTM., or another similar temperature
label. As discussed above, in some embodiments, a Reversible
Temperature Label may be used or a label with both reversible and
non-reversible components
Atmospheric Pressure
[0134] A decrease in atmospheric pressure may result in
unintentional and/or unscheduled and/or non-requested delivery of
fluid from a reservoir in an infusion pump to a user. A decrease in
pressure effects air that may be in the reservoir and/or may be
dissolved in the fluid in the reservoir. Some embodiments of
infusion pumps which may be affected are syringe infusion pumps and
those similar to a syringe infusion pump, which may include, but is
not limited to, various embodiments shown and described in U.S.
Pat. No. 7,498,563 issued Mar. 3, 2009 and entitled Optical
Displacement Sensor for Infusion Devices (Attorney Docket No. D78);
U.S. Pat. No. 7,306,578 issued Dec. 11, 2007 and entitled Loading
Mechanism for Infusion Pump (Attorney Docket No. C54); and PCT
Application Serial No. PCT/US09/060158 filed Oct. 9, 2009 and
entitled Infusion Pump Assembly, now Publication No. WO2010/042814,
published Apr. 15, 2010 (Attorney Docket No. F51WO) which are all
hereby incorporated herein by reference in their entireties, and
shown in FIGS. 1A-3. Thus, in operation, where the syringe infusion
pump experiences an atmospheric pressure decrease, an unintended
bolus may be delivered to a user. This presents a safety concern as
the unintended bolus may also be unknown to the user. Thus, the
user may experience an over delivery event which, in the
embodiments including an insulin pump, may result in a hypoglycemic
event.
[0135] An increase in atmospheric pressure may result in an
unintentional and/or unscheduled siphoning of fluid from the
tubing/cannula towards the reservoir in an infusion pump. Some
embodiments of infusion pumps which may be affected are those
similar to a syringe infusion pump, which may include, but is not
limited to, various embodiments shown and described in U.S. Pat.
No. 7,498,563 issued Mar. 3, 2009 and entitled Optical Displacement
Sensor for Infusion Devices (Attorney Docket No. D78); U.S. Pat.
No. 7,306,578 issued Dec. 11, 2007 and entitled Loading Mechanism
for Infusion Pump (Attorney Docket No. C54); and PCT Application
Serial No. PCT/US09/060158 filed Oct. 9, 2009 and entitled Infusion
Pump Assembly, now Publication No. WO2010/042814, published Apr.
15, 2010 (Attorney Docket No. F51WO), and 1A-3. Thus, in operation,
where the syringe infusion pump experiences an atmospheric pressure
increase, an unintended siphoning of fluid from the tubing/cannula
may occur which may result in a less than intended volume delivered
to a user. This presents a safety concern as the siphoning volume
may also be unknown to the user. Thus, the user may experience an
under delivery event which, in the embodiments including an insulin
pump, may result in a hyperglycemic event.
[0136] In some embodiments, the syringe infusion pump and/or the
remote controller for the syringe infusion pump may include a
pressure sensor, which in some embodiments may be an altimeter,
similar to those known in the art. The terms "pressure sensor" and
altimeter" may be used interchangeably herein. The altimeter may be
in communication with the pump processor and therefore, the data
from the altimeter may be used by the pump processor. In some
embodiments, the processor may include predetermined rate of change
and/or atmospheric pressure thresholds (either increases or
decreases) that trigger at least one response from the infusion
pump.
[0137] In some embodiments, the response may include notification
to the user. Thus, the infusion pump and/or a remote controller may
notify and/or alarm and/or alert the user where the altimeter sends
data indicating an increase and/or a decrease in atmospheric
pressure which has triggered a threshold. In some embodiments, the
processor may recognize, from the altimeter data, potential events,
e.g., airplane take-off, airplane decent, traveling to/from high
altitudes to low altitudes. These recognized events may, in some
embodiments, trigger at least one comment to the user, for example,
the pump and/or controller may alert and/or alarm the user with a
question, which may include, for example, but is not limited to,
"airplane take-off?" and/or "airplane decent?". Upon confirmation
by the user, the pump may suggest, e.g., by an alert and/or an
alarm e.g., either by an audio and/or visual signal to the user,
that the user disconnect from the cannula. Following, when
altimeter data indicates that a threshold "safe" altitude has been
reached and/or the user is at an appropriate altitude for a
predetermined period of time, the pump/controller may alert and or
alarm the user to reconnect to the cannula. Thus, in some
embodiments, any potential adverse effects caused by atmospheric
pressure changes may be minimized and/or mitigated and/or avoided
by notification to the user followed by user disconnect and/or
reconnect as appropriate.
[0138] Referring now also to FIG. 9, a method for atmospheric
pressure mitigation 600 is shown. In some embodiments, the pressure
sensor/altimeter sends data to a processor at predetermined
intervals 602. If the altimeter data indicates a predetermined
alert and/or alarm threshold 604, the processor may alert and/or
alarm the user to disconnect from the cannula 606. When the
altimeter indicates a predetermined appropriate/safe threshold has
been met 608, the processor may alert and/or alarm the user to
re-connect to the cannula 610. However, until the predetermined
appropriate threshold has been met 608, the altimeter continues to
send data to the processor at predetermined intervals 612.
[0139] In some embodiments, the altimeter may send data to the
processor at predetermined intervals which may be, but is not
limited to, every minute. In some embodiments, the frequency may
increase or decreased based on altimeter data. For example, in some
embodiments, where airplane take-off is confirmed by the user, the
altimeter may send data to the processor more frequently. In some
embodiments, once the user has reconnected, the altimeter may send
data to the processor based on entered events by the user. For
example, in some embodiments, where the user foresees airplane
travel, (airplane travel is used merely as an example, in other
embodiments, the event may be any event which may result in a
change in atmospheric pressure) the user may select either on the
pump and/or the controller, a menu option in the user interface to
indicate to the pump to be placed in "airplane mode". This mode may
also request the user to enter additional information, for example,
scheduled take-off time, and/or scheduled landing time. Thus, the
pump and/or controller may modify the frequency of the altimeter
data communication based on user input information. The user input
information may additionally be used by the pump and/or controller
to recognize changes in the events through readings from the
altimeter. For example, the processor may recognize that where a
decrease in atmospheric pressure may be anticipated based on a user
entered take-off time is not realized, the pump/controller may
request further information from the user regarding changed
take-off time. The user entered event information may additionally
be used by the processor to confirm and altimeter function and/or
accuracy. For example, where a reading during take-off is not as
expected, even within a preprogrammed margin of error, the
pump/controller may alarm/alert as this may indicate a malfunction
of the altimeter. In some embodiments, the pump/controller may then
alert the user to disconnect during take-off and decent.
[0140] In some embodiments, the data from the altimeter and/or data
from a pressure sensor may be used to modify the scheduled delivery
of fluid. Thus, the altimeter and/or pressure sensor may be in
communication with the infusion pump processor. A sensed changed in
pressure, either in a positive or negative direction, may be
communicated to the processor. In response, the processor may
communicate to the controller to either decrease or increase the
rate of delivery of the infusible fluid. For example, the
controller may increase or decrease any scheduled delivery for a
predetermined period of time by a predetermined percentage. In some
embodiments, the infusion pump may include a mode or other
preprogrammed delivery schedule modifier to address situations
where the infusion pump may experience an increase or decrease in
pressure which may effect the delivery of fluid. The mode may be
selected by a user when the user is experiencing or plans to
experience a change in pressure event, for example, but not limited
to, flying in an airplane. The user may select the mode which may
be termed an "airplane mode" in some embodiments (however, this is
merely an example of a name and also, the term may be used to
identify any change in pressure event in various embodiments and in
various embodiments is not limited to airplane events), and may
additionally specify whether taking off or landing, for example. In
response, the infusion pump may increase or decrease the rate of
delivery.
[0141] In some embodiments, where the altimeter data indicates a
change in pressure event which may result in an
unintentional/unintended increase or decrease in fluid delivery,
and/or where the user has indicated same to the pump and/or
controller, for example, but not limited to, one or more of the
following, through menu selection and/or manual entry and/voice
recognized command, the pump may enter an "airplane mode" which
may, in some embodiments, include a modification of the frequency
of determination of the location of the plunger. In some
embodiments, for example, as described above and/or in U.S. Pat.
No. 7,498,563 issued Mar. 3, 2009 and entitled Optical Displacement
Sensor for Infusion Devices (Attorney Docket No. D78), the infusion
pump may include at least one sensor for determining the location
of the plunger. Although, in some embodiments, this may be
accomplished by using the methods, apparatus and systems described
above, and/or in U.S. Pat. No. 7,498,563 issued Mar. 3, 2009 and
entitled Optical Displacement Sensor for Infusion Devices (Attorney
Docket No. D78), in other embodiments, other sensors for
determining plunger movement or plunger location may be used.
However, in the various embodiments, the frequency at which the
sensor determines the position of the plunger may vary in "airplane
mode". For example, in some embodiments, during normal operation,
the infusion pump may determine the position of the plunger before
and after a scheduled and/or requested delivery. However, in some
embodiments, in airplane mode, to determine a movement of the
plunger which may not be due to a scheduled and/or requested
delivery, the infusion pump may modify the frequency of the sensor
readings to determine the volume of fluid either siphoned or
delivered due to a change in pressure event. Thus, upon entering
airplane mode and/or upon the altimeter data triggering the mode,
the sensor may take readings at predetermined intervals, e.g.,
every 1 minute. In some embodiments, where the sensor readings
indicate a movement either towards delivery or siphoning, an
estimated volume of fluid either delivered or siphoned may be
presented to the user. Thus, the user may make appropriate changes
in therapy based on this information. In some embodiments, however,
the sensed volume of fluid either delivered and/or siphoned may be
used by the processor to modify the scheduled deliveries for a
predetermined period of time. In some embodiments, the
predetermined period of time may be dependant on many factors,
including, but not limited to, the volume of fluid for which the
infusion pump is correcting.
[0142] Referring to the description above with respect to
temperature changes and mitigation, in some embodiments, a similar
mode regarding sensing the position of the plunger may be entered
into automatically and/or manually upon a change of pressure
threshold being met. Thus, the various methods described regarding
the various embodiments pertaining to sensor frequency modification
and downstream modification of delivery may be used for pressure
mitigation.
[0143] In some embodiments, the infusion pump may include at least
one valve located downstream from the reservoir. In various
embodiments, the valve may be located anywhere between the distal
side of the reservoir to the cannula site, including, but not
limited to, built into the infusion set itself, including but not
limited to one or more of the following: in the tubing, in the
cannula, and/or on the distal end of the reservoir. In some
embodiments, the at least one valve may be a pressure/atmospheric
compensation valve. In some embodiments, the valve may be a micro
check valve similar to the one shown in Appendix A (Lee 250 Zero
Leak Chek.RTM. available from The Lee Company, Westbrook, Conn.,
USA), configured such that the valve remains fully closed with any
pressure differential that is higher on the cannula side of the
valve compared with the reservoir side of the valve (which may also
be referred to as "downstream from the valve" and "upstream of the
valve" respectively), i.e., when the valve is closed, no fluid may
flow back to the reservoir. In some embodiments, the outflow
cracking pressure may be selected such that a differential pressure
related to the change in altitude would not cause the valve to
open. For example, in some embodiments, the cracking pressure may
be set to 5 PSI. Thus, in this embodiment, at sea level, the
infusion pump may be required to generate 5 PSI to induce flow.
During, for example, pressure decreases, such as those experienced
during airplane flight, the infusion pump may be required to induce
1 PSI, for example, to induce flow due to the negative pressure
bias of the altitude change. In some embodiments, fluid flow based
on altitude changes alone may be eliminated and/or decreased and/or
mitigated. Thus, in embodiments such as these, the effect of
pressure changes may be mitigated while the user receives the
intended and/or scheduled and/or requested therapy deliveries.
Air Bubble Management
[0144] Air bubbles and/or air dissolved in the fluid in a syringe
reservoir similar to the ones shown and described in U.S. Pat. No.
7,498,563, issued Mar. 3, 2009 and entitled Optical Displacement
Sensor for Infusion Devices (Attorney Docket No. D78); U.S. Pat.
No. 7,306,578, issued Dec. 11, 2007 and entitled Loading Mechanism
for Infusion Pump (Attorney Docket No. C54); and PCT Application
Serial No. PCT/US2009/060158, filed Oct. 9, 2009 and entitled
Infusion Pump Assembly, now Publication No. WO 2010/042814,
published Apr. 15, 2010 (Attorney Docket No. F51WO), may affect
fluid delivery. Air bubbles and/or dissolved air in the fluid
de-gassing, displaces fluid, and may expand and/or be compressed,
which may effect delivery. Additionally, air bubbles may affect
occlusion detection in some embodiments of infusion pumps. For
example, with many infusion pump systems, occlusion detection is
performed using a strain beam/strain gauge to detect the upstream
pressure exerted from the plunger towards the strain beam. When the
pressure reaches a threshold, an occlusion is determined and/or
assumed by the system and generally, an occlusion alarm and/or
alert is given to the user. However, this occlusion detection
system relies on the fluid in the reservoir being
non-compressible.
[0145] When the fluid in the reservoir includes at least one air
bubble, as air is compressible, additional force within the
reservoir, due to an occlusion, must first compress the air bubbles
prior to the force being exerted onto the strain gauge. This may
ultimately require more force be present to detect an occlusion.
Thus, air bubbles in the reservoir may contribute to a delay in
occlusion detection. Therefore, for many reasons, including
occlusion detection, it may be desirable to minimize, mitigate
and/or eliminate air bubbles and/or dissolved air in the fluid in
the reservoir.
[0146] Additionally, as air bubbles increase in size, they may
increase the fluid pressure within the reservoir. Increased fluid
pressure within the reservoir may cause unintentional and/or
unscheduled delivery of a volume of fluid (which, in some
embodiments, is insulin).
Mitigation of Over-Delivery Caused by Air
[0147] With respect to mitigation of air bubbles to minimize and/or
eliminate unintentional and/or unscheduled fluid delivery, in some
embodiments, a three-way valve may be located downstream from the
reservoir. Referring now to FIG. 10, in some embodiments, both an
active check valve 650 and a passive check valve 652 may be located
downstream from the reservoir 654. In some embodiments, the active
check valve 650 may be opened for intended and/or scheduled and/or
requested therapy deliveries but otherwise, remain closed. The
passive check valve 652 may be cracked only when sufficient
pressure is exerted on the valve to overcome the valve. Thus, in
some embodiments, when there are no intended and/or scheduled
and/or requested therapy deliveries, the active valve 650 remains
closed. This continues unless and until the fluid pressure is
sufficient to overcome the passive check valve 652, thus, no fluid
will pass through either valve. However, in some cases, increased
fluid pressure, e.g., from an air bubble, may overcome the passive
check valve 652 (i.e., may overcome the cracking pressure of the
passive check valve 652) and flow outside of the pump (and in
various embodiments, the fluid flowing through the passive check
valve 652 may flow anywhere desired except to the user). Thus, in
this embodiment, only intended and/or scheduled and/or requested
therapy deliveries will be made, otherwise, increased fluid
pressure may be mitigated (and unintended and/or unscheduled fluid
deliveries avoided and/or mitigated and/or decreased) through use
of a passive check valve 652.
Air Bubble Minimization
[0148] Air bubbles may be introduced into the reservoir by various
methods and due to various circumstances, including, but not
limited to, fluid out-gassing. In some cases, the fluid may out-gas
after being introduced into the reservoir. This may occur as a
result of temperature. In some cases, for example, where insulin is
used as the fluid, insulin that is below room temperature may
experience a certain amount of out-gassing while coming to room
temperature. Comparatively, insulin that is and has been at room
temperature for a period of time may not experience as much
out-gassing, thus, insulin in this state may undergo minimal or
less out-gassing in the reservoir as compared with insulin that was
below room temperature when loaded into the reservoir.
[0149] Therefore, a method, system and apparatus for increasing the
out-gassing of insulin and/or a fluid prior to loading into the
reservoir may be desired. This may minimize the effects of
out-gassing, that is, minimize the effects of air bubbles in the
reservoir.
[0150] Referring now to FIG. 11, in some embodiments, a fill
adapter device 700 may be used to minimize the effects of
out-gassing. In some embodiments, the fill adapter 700 may be a
reusable fill adapter, however, in other embodiments; the fill
adapter 700 may be disposable. In some embodiments, the fill
adapter 700 device may be connected to the vial 702 (i.e.,
configured to be connected and/or removably attached to a vial) of
infusible fluid to be used while filling and/or partially filling a
reservoir/syringe 704 with infusible fluid which in some
embodiments is insulin. In some embodiments, the fill adapter 700
may be attached and/or removably attached to the vial 702 at
manufacture and in some embodiments; a user may attach the fill
adapter 700 at the time of use (and in some of these embodiments,
the fill adapter 700 may be removably attached). In some
embodiments, therefore, a vial 702 may be provided together with
the fill adapter 700 and in some embodiments, the reservoir 704 may
be provided to a user together with the fill adapter 700. In other
embodiments, the fill adapter 700 may be a separate device from the
vial 702 and/or reservoir 704. In some embodiments, the fill
adapter 700 may additionally include a needle (not shown)
connecting the fluid from the vial to the fluid pathway 712. In
some embodiments, as the fill adapter 700 is being attached to the
vial 702, the needle
[0151] The device may include a heat exchanger which may include a
heating element 706 and a fluid pathway 712, for example, but not
limited to, a length of tubing/fluid pathway (which may be made
from glass and/or plastic or any fluid compatible material). The
fluid pathway 712 may be fluidly connected to a septum and/or a
filling needle input 714. In some embodiments the length of tubing
may be any length and/or diameter to most efficiently and
effectively induce out-gassing. While filling the reservoir/syringe
704 (which may, in some embodiments, include at least one plunger
708), the fluid enters and passes through the heat exchanger
including the fluid pathway 712 which is heated by the heating
element 706 where it may be heated to a predetermined temperature.
While being heated to the predetermined temperature, out-gassing
may occur.
[0152] Some embodiments of the fill adapter 700 include a heat
source and/or heating element 706. In various embodiments, the
heating element 706 may be any heating element known in the art
which may include, but is not limited to the following, inductive,
optical, RF, microwave, electrical or other.
[0153] In some embodiments, the fluid path 712 and/or the fill
adapter 700 may be designed to heat the fluid at a desired and/or
predetermined rate. Thus, in some embodiments, there may be
additional features on the fill adapter 700 to control the rate of
heating of the fluid and or the flow rate of the fluid through the
heating element 706. These may include, but are not limited to, a
pump and/or an active valve.
[0154] In some embodiments, the fluid may be heated to room
temperature. In other embodiments, the fluid may be heated to less
than room temperature and in still other embodiments; the fluid may
be heated to above room temperature. In some embodiments, the fill
adapter 700 may include a processor (not shown) which may control
the heating of the fluid according to one or more preprogrammed
profiles. The one or more profiles may be designed for various
situations and/or various types of fluids. Depending on the desired
temperature, the heat exchanger and/or the fill adapter 700 may be
designed accordingly.
[0155] Thus, in various embodiments, use of an embodiment of the
fill adapter 700 may act to accomplish at least, but not limited
to, one or more of the following: minimize, decrease and/or
eliminate downstream effects of out-gassing; minimize, decrease
and/or eliminate the subjective amount of out-gassing such that the
amount of out-gassing is controlled and/or predictable and
therefore may be mitigated through other means; decrease, minimize,
eliminate and/or lessen the occurrence of out-gassing; stabilize
the temperature of the fluid to minimize potential effects of the
temperature increase between, for example, refrigerated temperature
and room temperature; decrease, eliminate, and/or minimize and/or
lesson the effects of out-gassing in the reservoir 704, including
but not limited to, volume changes in the reservoir 704.
[0156] In some embodiments, there may be an air trap and/or a
hydrophobic filter (not shown) or other to allow the escape of the
air from the heat exchanger. Thus, while the fluid is heated to the
predetermined temperature out-gassing occurs and therefore may
minimize out-gassing which may otherwise have occurred after
filling a reservoir and/or syringe 704.
[0157] In some embodiments, a heating apparatus (not shown) may be
used to heat the reservoir 704 following fill and/or partial fill
(the term "fill" may be used to refer to the transfer of any volume
of fluid into the syringe/reservoir, regardless or whether the
volume of fluid reaches maximum capacity or partial capacity) of
the reservoir 704. The heating apparatus may be a
nondisposable/reusable type apparatus which may include a heating
element, e.g., inductive, optical, RF, microwave, electrical or
other. The heating apparatus may be configured such that the filled
reservoir is accommodated in heating communication with the heating
element. The heating element may be located such that heat may be
communicated to the reservoir and the heat may heat the fluid
within the reservoir to a desired temperature. In some embodiments,
the heating apparatus may be designed to heat the fluid at a
desired rate. Thus, in some embodiments, there may be additional
features on the heating apparatus to control the rate of heating of
the fluid.
[0158] In some embodiments, the fluid may be heated to room
temperature. In other embodiments, the fluid may be heated to less
than room temperature and in still other embodiments; the fluid may
be heated to above room temperature. In some embodiments, the
heating apparatus may heat the fluid according to one or more
preprogrammed profiles. The one or more profiles may be designed
for various situations and/or various types of fluids. Depending on
the desired temperature, the heating apparatus may be designed
accordingly.
[0159] Thus, in various embodiments, use of an embodiment of the
heating apparatus may act to accomplish at least, but not limited
to, one or more of the following: decrease, minimize and/or
eliminate downstream effects of out-gassing; decrease, minimize
and/or eliminate the subjective amount of out-gassing such that the
amount of out-gassing is controlled and/or predictable and
therefore may be mitigated through other means; decrease, minimize
and/or eliminate and/or lessen the occurrence of out-gassing;
stabilize the temperature of the fluid to minimize potential
effects of the temperature increase between, for example,
refrigerated temperature and room temperature; decrease, minimize
and/or eliminate and/or lesson the effects of out-gassing in the
reservoir, including but not limited to, volume changes in the
reservoir.
[0160] During the heating, the fluid may out-gas. Thus, following
heating, the reservoir may be removed from the heating apparatus
and air may be pushed out of the syringe/reservoir through, for
example, but not limited to, a filling needle 710, prior to loading
the reservoir 704 into the infusion pump. Thus, the heating
apparatus may minimize and/or eliminate thermally produced fluid
delivery errors.
[0161] In some embodiments, degassing of the fluid may be
accomplished prior to loading fluid into a reservoir or prior to
loading a filled reservoir into an infusion pump by subjecting the
fluid to a partial vacuum. This may be accomplished through a
number of embodiments, including, but not limited to, the
following.
[0162] In some embodiments, once fluid is filled into the
reservoir, the filling needle may then be removed from the
reservoir and the reservoir may be capped with a cap that does not
allow the movement of fluid in or out of the reservoir. The plunger
may be pulled back to apply a vacuum to the fluid within the
reservoir. Out-gassing may occur. Released air may then be pushed
out of the reservoir prior to loading into an infusion pump.
[0163] In some embodiments, following filling of the reservoir, the
reservoir may be placed into a device or other where the reservoir
is put under a partial vacuum. The fluid may out-gas. Next, the
reservoir may be loaded into the infusion pump.
[0164] In some embodiments, in addition to heating to out-gas, a
system may also combine a vacuum with an elevated
temperature/heating element, which may result in heating the fluid
to a higher temperature. In some embodiments, the temperature
increase may be minimized when applied together with a vacuum.
Additionally, the vacuum applied may be minimized when applied
together with a temperature increase. Thus, in some embodiments,
where the fluid is heated and a vacuum is applied to the fluid, the
temperature increase and/or the level of vacuum applied may be
minimized. Thus, in some embodiments, it may be desirable to apply
as low a vacuum as possible, thereby decreasing the amount of
turbulence and/or rate of flow through a heat exchanger and/or
minimizing the contact area over a heat exchange surface, and
therefore minimize and or prevent extreme temperature and/or
extreme pressure change. This may be desirable for many reasons,
including, but not limited to, maintaining the viability of the
fluid.
[0165] In some embodiments, while under pressure, the fluid may be
removed from a vial into a reservoir and/or syringe or other, and
once the desired volume of fluid has been loaded into the
reservoir/syringe or other, the fluid path between the
reservoir/syringe and the vial may be closed and the syringe
plunger may continue to be pulled back, i.e., applying a vacuum
onto the fluid. Following, the syringe or other may be vibrated
and/or shocked and/or a force may be provided at a predetermined
point for a predetermined time, i.e., a force pulse. This may
enhance/amplify air bubble formation i.e., fluid de-gas, and thus,
in some embodiments, following vibration/force application, the
air/gas may be pressed out of the reservoir/syringe.
[0166] In some embodiments, an automated filling device may be used
which may connect a reservoir/syringe to a vial of fluid by a fluid
line, which, in some embodiments, may be a filling needle. In some
embodiments, the device may automate the filling of the
reservoir/syringe. Following, in some embodiments, the device may
close/occlude the fluid line and provide the vibration and/or force
to the reservoir/syringe (i.e., pulling a vacuum into the
reservoir/syringe). In some embodiments, this method may be
completed more than once, e.g., 2 or more times and/or until, in
some embodiments, based on the volume of fluid in the
reservoir/syringe and the amount of air extracted on any given
attempt, the device may determine whether a threshold volume of air
has been removed from the fluid, i.e., there may be a predetermined
threshold goal amount of air to be extracted. In some embodiments a
syringe having a volume, for example, of 1.5-5 cc, may be used and
filled to half or a portion of the volume, followed by a vacuum
being applied. In some embodiments, the device may include a camera
and/or other sensor to determine the volume of fluid before and
after air extraction/de-gas to determine if the threshold goal has
been met. In some embodiments, the device may communicate with the
controller for the infusion pump and/or the pump to input the
amount of fluid in the reservoir prior to the reservoir being
loaded into the infusion pump. In some embodiments, this system may
be beneficial for many reasons, including but not limited to,
improving air mitigation and increasing the accuracy of the volume
of fluid filled into a syringe/reservoir. In some embodiments, the
above-described system and method may include an optical sensor or
other sensor to determine the plunger's displacement.
[0167] In some embodiments, the automated filling device may
measure the temperature of the fluid and this may be input into a
control system 728 that determines the amount of effort that is
exerted onto the filled reservoir/syringe, i.e., how much force is
applied onto the syringe to extract the air. For example, in colder
temperatures it may be more difficult to remove the air and
therefore, may require more or longer application of vacuum and/or
more or longer application of vibration and/or force or both. In
some embodiments, the temperature of the fluid may be input into a
control system 728 and the amount of heating of the fluid may be
determined using the temperature readings. In some embodiments, the
temperature readings may be used to determine both the amount of
force applies to the syringe and the amount of heating applied to
the fluid.
[0168] In some embodiments, to minimize the vacuum applied to the
reservoir/syringe, for example, where it may be desirable to
protect the fluid, the device, in some embodiments, may measure the
force (e.g., may include a pressure sensor) being pulled on the
syringe to correlate the force with the pressure being exerted onto
the fluid and therefore, it may be determined when the vacuum has
been depleted such that the vacuum no longer is working. Thus, the
force or pull on the reservoir/syringe may be an output to
determine when to stop/cease the force or pull and also, to
determine when a sufficient amount of air has likely been pulled
from the fluid, based on the force.
[0169] In some embodiments, using an optical sensor, for example,
an optical displacement sensor, to determine the displacement of
the plunger, together with the pressure sensor to determine the
pressure being exerted onto the fluid, the control system 728 may
calculate the volume of air removed as well as correlate pressure
with displacement.
[0170] Referring now to FIG. 12 one embodiment of a system for
maintaining a lower positive pressure within a fluid vial 702 is
shown. It may be desirable to maintain the fluid which will
eventually be used in a reservoir at or near atmospheric pressure
rather than at a pressure which may result in a greater volume of
dissolved gas in the fluid. Thus, in some embodiments, maintaining
the fluid at or near atmospheric pressure may minimize post
reservoir fill fluid out-gassing as the amount/volume of dissolved
gas in the fluid is limited compared to embodiments where the
pressure inside the vial is higher or increases. As shown in the
FIG. 12, in some embodiments, a needle 716 is inserted through the
septum 718 of the vial 702. The needle 716 may include two ends
which are each open to the atmosphere. However, in some
embodiments, the end exposed to the outside of the vial 702 may
include a filter, which, in some embodiments, may be a hydrophobic
filter (not shown), to maintain sterility and/or to maintain the
needle as dry.
[0171] In some embodiments, the needle 716 may include a one-way
check valve 720 on one end of the needle 716. In some embodiments,
the one-way check valve 720 may have a 1 or 2, for example, PSI
cracking pressure. When the pressure within the vial 702 is high
enough, the vial 702 will vent. This may lower the positive
pressure in the vial. In some embodiments, the check valve 720 may
limit the internal vial 702 pressure so that it is no greater than
atmospheric pressure plus 1 or 2, for example, additional PSI.
Thus, in these embodiments, the apparatus/system shown in FIG. 12
may be beneficial for many reasons, including, but not limited to,
limiting the pressure due to atmospheric pressure change.
[0172] Referring now also to FIG. 13, in some embodiments, the
device/system shown in FIG. 12 may additionally include a vial
manager apparatus 722 that may be sized and shaped to accommodate
the vial 702 such that the vial manager apparatus 722 may be
removably attached to the vial 702. In some embodiments, the vial
manager apparatus 722 may include a pump 724, which may also be
termed an air pump, in fluid connection with the inside of the vial
702 through a needle 716. The pump may be used for pumping air out
of the vial 702, which may be, in some embodiments, an
electromechanical pump and/or a pump that may be manually operated.
The pump 724 may be used to apply a low vacuum on the inside of the
vial 702. In some embodiments, the pump 724 may be a diaphragm pump
that may be battery operated and works to pull, e.g., a PSI less
than atmospheric pressure, which, in various embodiments, may
include pulling at PSI from less than 1 to 12, for example, vacuum
on the inside of the vial 702. In some embodiments, the vial
manager apparatus 722 may include a power source, i.e., a battery
726, to provide power to at least the pump and/or the processor. In
some embodiments, the vial manager apparatus 722 may additionally
include a processor 726 and/or a timer that may be preprogrammed to
turn the pump 724 on and off to limit the vacuum, e.g., the pump
724 may pump for 30 seconds every 5 minutes. However, in some
embodiments, the duration that the pump is on and/or the frequency
of the durations may depend on the leak rate of the vial 702. In
some embodiments, the pump 724 may run constantly.
[0173] In some embodiments, the vial manager apparatus 722 may
additionally include a pressure sensor (not shown) located within
the path of the needle 716. In various embodiments, the pressure
sensor may communication with the processor/control system 728 and
the pump 724 may be activated based on the pressure data from the
pressure sensor. In some embodiments, where a pressure sensor is
included in the needle 716, the device may determine if the vial
702 has tipped using the pressure sensor reading. In some
embodiments, where a tip is determined, the vial manager apparatus
722 may alarm using any type of alarm including but not limited to,
blinking or one or more lights, audio alarm and/or vibratory alarm.
Determining when the vial 702 has tipped may be beneficial for many
reasons, including but not limited to, once the vial 702 has
tipped, the air pump 724 may not be able to pump air since fluid
may be in contact with the needle 716. Thus, the vial manager
apparatus 722 may not be able to pull a vacuum on the vial 702.
Thus, it may be desirable to alarm/alert once the vial 702 has
tipped. This alarm/alert may, in some embodiments, be triggered by
the pressure sensor.
[0174] In some embodiments, the vial manager apparatus 722 may
include one or more lights to indicate conditions, for example, one
or more green lights and one or more red lights, indicating the
status of the vial manager apparatus 722 and/or the vial 702. In
some embodiments, the vial manager apparatus 722 may include one
light which may, by, e.g., blinking, indicate various status
conditions.
[0175] In some embodiments, the vial manager apparatus 722 may
include at least one accelerometer that may be connected to a
processor 728. This may be used to determine when/if the vial has
tipped while in storage. In some embodiments, the vial manager
apparatus 722 may additionally include at least one alarm (for
example, vibratory and/or audio and/or visual) to alert the
user/care giver that the device has tipped. In some embodiments,
the needle 716 may include a filter, which, in some embodiments,
may be a hydrophobic filter (not shown). The hydrophobic filter may
be beneficial for many reasons, including, but not limited to,
protecting the air pump 724 from pumping fluid
[0176] In some embodiments, the vial manager apparatus 722
processor 728 may include a vial manager control system. The system
may include at least one temperature sensor which may be located
inside the vial manager apparatus 722 and may be in communication
with the processor 728. The at least one temperature sensor may
provide temperature data on a predetermined frequency, e.g., every
5 minutes, and at a threshold high or low temperature reading, the
apparatus 702 may alarm/alert. In some embodiments, the vial
manager apparatus 722 may include a time keeper which, when, for
example, the vial manager apparatus 722 is connected to a vial 702,
the timer may be initiated, and at a predetermined time, e.g., 28
days, the vial manager apparatus 722 may alarm/alert the user that
the vial should be replaced and/or has been in use for the
predetermined amount of time. This may be beneficial for many
reasons, including, but not limited to, alerting the user when the
fluid inside the vial 702 may be passed the expiration date thereby
ensuring the user does not use expired fluid and/or medication for
therapy.
[0177] The vial manager apparatus 722, in some embodiments, may be
made from any material, including, but not limited to, any type of
plastic and/or metal. In some embodiments, the vial manager
apparatus 722 is placed over the top of the vial 702 and once the
needle 716 pierces the septum 718, the timer may initiate a
countdown. Thus, the vial manager apparatus 722 provides a system
for maintaining the pressure in a vial 702 and also, for ensuring
providing a method for determining when the vial 702 was first
used, i.e., when the needle 716 is first inserted into the vial
702. In some embodiments, the vial manager apparatus 722 may be
used while a vial 702 is "in use", e.g., while a user is using the
vial 702 for therapy.
[0178] In some embodiments, the vial manager apparatus 722 may
include a disposable portion and a reusable portion. For example,
in some embodiments, the portion of the vial manager apparatus 722
that connects with the vial 702, including the needle 716, may be
contained in the disposable portion. Thus, the reusable portion may
include, but is not limited to, the processor, power source, and
pump, etc. This may be beneficial for many reasons, including, but
not limited to, reusability of many elements of the vial manager
apparatus 722.
[0179] In some embodiments, a stick-on pressure and/or force gauge
may be placed on a vial of fluid, and in some embodiments, on a
vial of insulin. The gauge may tell the user the current pressure
of the vial. In some embodiments, the pressure may be indicated as
various color shades. Any stick-on pressure gauge may be used
including a non-reversible pressure label. In some embodiments, a
Reversible Pressure Label may be used or a label with both
reversible and non-reversible components may be used.
[0180] In some embodiments, a pressure and/or force label may be
included on the vial. It may be desirable to include a pressure
and/or force label for many reasons, including, but not limited to,
determining whether a pressure/force was exerted onto the vial that
may be indicative of an elevated volume of air saturation in the
fluid, i.e, may indicate that there may have been an increase in
the volume of dissolved air in the fluid which may lead to
additional out-gassing of the air. This may, in some embodiments,
be indicative that the vial of fluid may be compromised and
therefore, it may be desirable for a user/caregiver to know whether
the vial has been compromised.
[0181] In various infusion device, for example, including those
shown and described herein as well as in U.S. Pat. No. 7,498,563,
issued Mar. 3, 2009 and entitled Optical Displacement Sensor for
Infusion Devices (Attorney Docket No. D78); U.S. Pat. No.
7,306,578, issued Dec. 11, 2007 and entitled Loading Mechanism for
Infusion Pump (Attorney Docket No. C54); PCT Application Serial No.
PCT/US2009/060158, filed Oct. 9, 2009 and entitled Infusion Pump
Assembly, now Publication No. WO 2010/042814, published Apr. 15,
2010 (Attorney Docket No. F51WO); U.S. patent application Ser. No.
11/704,899, filed Feb. 9, 2007 and entitled Fluid Delivery Systems
and Methods, now U.S. Publication No. US-2007-0228071-A1 published
Oct. 4, 2007 (Attorney Docket No. E70); U.S. patent application
Ser. No. 12/347,985, filed Dec. 31, 2008 and entitled Infusion Pump
Assembly, now U.S. Publication No. US-2009-0299277-A1 published
Dec. 3, 2009 (Attorney Docket No. G75); and U.S. patent application
Ser. No. 12/560,106 filed Sep. 15, 2009 and entitled Systems and
Methods for Fluid Delivery, now U.S. Publication No.
US-2010-0185142-A1, published Jul. 22, 2010 (Attorney Docket No.
G47), which are all hereby incorporated herein by reference in
their entireties, in some embodiments, the disposable/reservoir
portion of the infusion pump may include one or more coatings to
mitigate air bubbles. The coatings may be applied to the fluid
pathways within the disposable/reservoir portion and/or to the
outside of the reservoir. With respect to coatings applied to the
fluid pathways, in some embodiments, a coating may be applied to
change the surface tension properties such that the surface is more
hydrophilic. Increasing the hydrophilic properties of the fluid
path may alter the angle of contact between an air bubble and the
fluid path surface, thus enabling mitigation of the air bubble by
priming or pumping. In some embodiments, the coating may be applied
to the hard plastic portion and/or the membrane portion.
[0182] With respect to the reservoir, in some embodiments, a
coating may be applied to the outside of the reservoir. The coating
may be selected to decrease the permeability of the reservoir thus,
may decrease the incidence of air permeating the reservoir and
therefore, may minimize and/or decrease and/or lessen the incidence
the air bubbles in the reservoir. As the coating may be applied to
the outside of the reservoir, the coating used may be anything
desired and is not limited to fluid compatible materials. In some
embodiments, the coating may include, but is not limited to, one or
more of the following: parylene and/or oil. In some embodiments,
the reservoir may be coated on the outside and the coating may
prevent air diffusion inward and water vapor diffusion outward. In
some embodiments, the inside of the reservoir may be coated with a
material, including, but not limited to, a parylene and/or oil
and/or a hydrophilic coating material made by SurModics, Inc. of
Eden Prairie, Minn., U.S.A., or other hydrophilic coatings that may
be compatible with the fluid in the reservoir. In some embodiments,
this may be desirable to allow for air to move through the
reservoir material.
Altimeter
[0183] Referring now to the various embodiments of infusion pumps
including those described in U.S. Pat. No. 7,498,563, issued Mar.
3, 2009 and entitled Optical Displacement Sensor for Infusion
Devices (Attorney Docket No. D78); U.S. Pat. No. 7,306,578, issued
Dec. 11, 2007 and entitled Loading Mechanism for Infusion Pump
(Attorney Docket No. C54); and PCT Application Serial No.
PCT/US2009/060158, filed Oct. 9, 2009 and entitled Infusion Pump
Assembly, now Publication No. WO 2010/042814, published Apr. 15,
2010 (Attorney Docket No. F51WO), and those infusion pumps known in
the art, in some embodiments, an altimeter may be introduced to the
infusion pump.
[0184] Referring to U.S. patent application Ser. No. 11/704,899,
filed Feb. 9, 2007 and entitled Fluid Delivery Systems and Methods,
now U.S. Publication No. US-2007-0228071-A1 published Oct. 4, 2007
(Attorney Docket No. E70); and U.S. patent application Ser. No.
12/347,985, filed Dec. 31, 2008 and entitled Infusion Pump
Assembly, now U.S. Publication No. US-2009-0299277-A1 published
Dec. 3, 2009 (Attorney Docket No. G75), which are both hereby
incorporated herein by reference in their entireties, in some
embodiments, the altimeter may be used in Acoustic Volume
Measurements, for example, for changing the dampening based on
ambient pressure. Still referring to U.S. patent application Ser.
No. 11/704,899, filed Feb. 9, 2007 and entitled Fluid Delivery
Systems and Methods, now U.S. Publication No. US-2007-0228071-A1
published Oct. 4, 2007 (Attorney Docket No. E70); and U.S. patent
application Ser. No. 12/347,985, filed Dec. 31, 2008 and entitled
Infusion Pump Assembly, now U.S. Publication No. US-2009-0299277-A1
published Dec. 3, 2009 (Attorney Docket No. G75), in some
embodiments, the disposable/reservoir portion of the infusion pump
may include an intravenous needle connected to the tubing, rather
than an infusion set, as discussed in various embodiments. Thus, in
some embodiments, the infusion pump may be used to administer
intravenously and is not limited to subcutaneous infusion. In some
of these embodiments, the fluids infused may be those used to
minimize bleeding, for example, but not limited to, morphine and/or
blood pressure lowering medications and/or other similar
therapeutics.
Cannula Detection
[0185] In some embodiments of some infusion pumps, the cannula may
be inserted into the user such that the cannula may be located
directly between the user's skin and the infusion pump. This
presents some challenges including, but not limited to, determining
when the cannula has become dislodged and determining an occlusion
in the cannula.
[0186] In some embodiments, two electrode contracts may be used.
One electrode contact may be in located between the infusion pump
and the user's skin and is in contact with the user's skin, the
other that is in electrical contact with the infusion pump. An
electrical path between the two electrodes is established. Using
high impedance/low voltage, the impendence between the two
electrodes is determined and tracked. If the impedance reaches a
very high value, for example, "infinity", an occlusion and/or
cannula dislodgement may be inferred. The user may be alerted. This
may be desirable because if there is cannula dislodgement, the user
is no longer receiving their fluid therapy. In the case of an
insulin pump, the user may experience an hyperglycemic event. Early
detection and alerting of the user may increase the safety of these
types of infusion pumps.
[0187] While the principles of the invention have been described
herein, it is to be understood by those skilled in the art that
this description is made only by way of example and not as a
limitation as to the scope of the invention. Other embodiments are
contemplated within the scope of the present invention in addition
to the exemplary embodiments shown and described herein.
Modifications and substitutions by one of ordinary skill in the art
are considered to be within the scope of the present invention.
* * * * *