U.S. patent application number 15/865335 was filed with the patent office on 2018-07-12 for systems and methods for wearable emergency drug injection devices.
This patent application is currently assigned to Verily Life Sciences LLC. The applicant listed for this patent is Verily Life Sciences LLC. Invention is credited to Michael Chen, Ethan Glassman, Benjamin Krasnow, Clarissa Lui, Tushar Parlikar, Todd Whitehurst.
Application Number | 20180193563 15/865335 |
Document ID | / |
Family ID | 60942921 |
Filed Date | 2018-07-12 |
United States Patent
Application |
20180193563 |
Kind Code |
A1 |
Krasnow; Benjamin ; et
al. |
July 12, 2018 |
SYSTEMS AND METHODS FOR WEARABLE EMERGENCY DRUG INJECTION
DEVICES
Abstract
One example device includes a housing defining at least a first
chamber and a second chamber; an injector disposed within the
housing and comprising: a hollow needle coupled to a first piston,
the first piston disposed and translatable within the first chamber
towards a first end of the first chamber, the first piston defining
a void intersecting a hollow portion of the hollow needle; a first
propellant disposed within the first chamber and positioned to
force the first piston towards the first end of the first chamber
in response to activation of the first propellant; a dispenser
disposed within the housing and comprising: a second piston
disposed and translatable within the second chamber towards a first
end of the second chamber; a second propellant disposed within the
second chamber and positioned to force the second piston towards
the first end of the second chamber in response to activation of
the second propellant; and wherein translation of the first piston
to the first end of the first chamber exposes the void to the first
end of the second chamber.
Inventors: |
Krasnow; Benjamin; (Redwood
City, CA) ; Whitehurst; Todd; (Redwood City, CA)
; Glassman; Ethan; (Palo Alto, CA) ; Parlikar;
Tushar; (Somerville, CA) ; Chen; Michael;
(Sunnyvale, CA) ; Lui; Clarissa; (Menlo Park,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Verily Life Sciences LLC |
South San Francisco |
CA |
US |
|
|
Assignee: |
Verily Life Sciences LLC
South San Francisco
CA
|
Family ID: |
60942921 |
Appl. No.: |
15/865335 |
Filed: |
January 9, 2018 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
62505457 |
May 12, 2017 |
|
|
|
62444237 |
Jan 9, 2017 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 5/3153 20130101;
A61M 5/19 20130101; A61M 2005/1581 20130101; A61M 5/2066 20130101;
A61M 5/158 20130101; A61M 5/1723 20130101; A61M 2205/3569 20130101;
A61M 37/0069 20130101; A61M 2209/088 20130101; A61M 2205/8206
20130101; A61M 2230/201 20130101; A61M 5/3287 20130101; A61M
2005/206 20130101; A61K 9/0024 20130101; A61M 5/3234 20130101; A61M
2205/123 20130101; A61M 2005/1585 20130101; A61M 5/155 20130101;
A61M 5/24 20130101; A61M 2005/2026 20130101; A61M 2205/0266
20130101; A61M 2005/2086 20130101; A61M 2205/3592 20130101; A61M
5/2046 20130101; A61M 5/14248 20130101; A61M 2205/3303 20130101;
A61M 2005/14256 20130101 |
International
Class: |
A61M 5/20 20060101
A61M005/20; A61M 5/19 20060101 A61M005/19; A61M 5/172 20060101
A61M005/172; A61M 5/315 20060101 A61M005/315; A61M 5/32 20060101
A61M005/32 |
Claims
1. A device for injecting a substance into a patient, comprising: a
housing defining at least a first chamber and a second chamber; an
injector disposed within the housing and comprising: a hollow
needle corresponding to a first piston, the first piston disposed
and translatable within the first chamber towards a first end of
the first chamber, the first piston defining a void intersecting a
hollow portion of the hollow needle; a first propellant disposed
within the first chamber and positioned to force the first piston
towards the first end of the first chamber in response to
activation of the first propellant; a dispenser disposed within the
housing and comprising: a second piston disposed and translatable
within the second chamber towards a first end of the second
chamber; a second propellant disposed within the second chamber and
positioned to force the second piston towards the first end of the
second chamber in response to activation of the second propellant;
and wherein translation of the first piston to the first end of the
first chamber exposes the void to the first end of the second
chamber.
2. The device of claim 1, further comprising a first propellant
activator and a second propellant activator, the first propellant
activator positioned proximate the first propellant and configured
to activate the first propellant, the second propellant activator
positioned proximate the second propellant and configured to
activate the second propellant.
3. The device of claim 2, wherein the first and second propellants
comprise nitrocellulose and the first and second propellant
activators comprise resistors.
4. The device of claim 3, wherein the first propellant comprises
nitrocellulose in a cotton format and the second propellant
comprises nitrocellulose in a paper format.
5. The device of claim 1, wherein the housing is configured to be
worn by a patient.
6. The device of claim 5, further comprising a strap, and wherein
the housing is configured to strapped to a patient's arm or
torso.
7. The device of claim 1, further comprising epinephrine disposed
within the second chamber.
8. The device of claim 7, wherein the epinephrine comprises
approximately 0.3 milliliters of epinephrine.
9. The device of claim 7, wherein the epinephrine comprises
approximately 1 milliliter ("ml") of epinephrine, and further
comprising: a piston stop disposed within the second chamber, the
piston stop configured to halt movement of the second piston
towards the first end of the second chamber after approximately 0.3
mls of epinephrine have been dispensed through the hollow
needle.
10. The device of claim 1, further comprising a glucagon diluting
solution disposed within the second chamber, and a glucagon powder
disposed within the void.
11. The device of claim 10, wherein the glucagon diluting solution
comprises approximately 1 milliliter of glucagon diluting solution
and wherein the glucagon powder comprises approximately 1 milligram
of glucagon powder.
12. The device of claim 1, wherein the hollow needle comprises a
flexible 22-gauge hollow needle and is approximately 1 inch
long.
13. The device of claim 12, wherein the hollow needle is
constructed from Nitinol.
14. The device of claim 1, further comprising a needle retraction
mechanism.
15. The device of claim 14, wherein the needle retraction mechanism
comprises a spring.
16. The device of claim 1, wherein the housing is a first housing,
and further comprising: a second housing releasably couplable to
the first housing; a battery disposed within the second housing; a
first switch electrically coupling the battery and the first
propellant, the first switch arranged to provide an electrical
current to the first propellant when the first switch is closed;
and a second switch electrically coupling the battery and the
second propellant, the second switch arranged to provide an
electrical current to the second propellant when the second switch
is closed.
17. The device of claim 16, wherein: the first switch is coupled to
the battery via a first capacitor, the first capacitor configured
to store a first electrical charge when the first switch is open,
and to discharge the first electrical charge to the first
propellant when the first switch is closed; and the second switch
is coupled to the battery via a second capacitor, the second
capacitor configured to store a second electrical charge when the
second switch is open, and to discharge the second electrical
charge to the second propellant when the second switch is
closed.
18. The device of claim 16, further comprising a manipulandum
coupled to the first and second switches, the manipulandum
configured to initiate a firing sequence in response to an
input.
19. The device of claim 18, wherein the firing sequence comprises:
closing the first switch; and subsequent to closing the first
switch, closing the second switch.
20. The device of claim 16, further comprising a wireless receiver
and an antenna, the wireless receiver in communication with the
first switch and the second switch and configured to initiate a
firing sequence in response to receipt of a firing signal.
21. The device of claim 20, wherein the firing sequence comprises:
closing the first switch; and subsequent to closing the first
switch, closing the second switch.
22. A method comprising: receiving an activation signal; in
response to receiving the activation signal, activating a first
propellant of an injection device to force a first piston towards a
first end of a first chamber, the injection device comprising a
hollow needle corresponding to the first piston, the first piston
disposed and translatable within the first chamber towards the
first end of the first chamber, the first piston defining a void
intersecting a hollow portion of the hollow needle, and a second
piston disposed and translatable within a second chamber towards a
first end of the second chamber; subsequent to activating the first
propellant, activating a second propellant of the injection device
to force the second piston towards the first end of the second
chamber, an injectable substance disposed within the second
chamber; and wherein translation of the first piston to the first
end of the first chamber exposes the void to the first end of the
second chamber.
23. The method of claim 22, further comprising receiving a user
input from a manipulandum coupled to the injection device, wherein
the activation signal is received in response to receiving the user
input.
24. The method of claim 22, further comprising receiving the
activation signal from a remote device.
25. The method of claim 24, wherein the activation signal is
received wirelessly from the remote device.
26. The method of claim 24, wherein the remote device comprises a
continuous glucose monitor or an insulin pump.
27. The method of claim 22, further comprising retracting the
hollow needle.
28. The method of claim 22, wherein the injectable substance
comprises epinephrine.
29. The method of claim 28, wherein the epinephrine comprises
approximately 0.3 milliliters of epinephrine.
30. The method of claim 28, wherein the epinephrine comprises
approximately 1 milliliter ("ml") of epinephrine, and further
comprising: a piston stop disposed within the second chamber, the
piston stop configured to halt movement of the second piston
towards the first end of the second chamber after approximately 0.3
mls of epinephrine have been dispensed through the hollow
needle.
31. The method of claim 22, wherein the injectable substance
comprises a glucagon diluting solution disposed within the second
chamber, and a second injectable substance comprises a glucagon
powder disposed within the void.
32. The method of claim 31, wherein the glucagon diluting solution
comprises approximately 1 milliliter of glucagon diluting solution
and wherein the glucagon powder comprises approximately 1 milligram
of glucagon powder.
33. A device for injecting a substance into a patient, comprising:
a housing defining at least one chamber; and an injector disposed
within the housing and comprising: a hollow needle corresponding to
a piston, the piston disposed and translatable within the chamber
towards a first end of the chamber, the piston defining a void
intersecting a hollow portion of the hollow needle; and a
propellant disposed within the chamber and positioned to force the
piston towards the first end of the chamber in response to
activation of the propellant.
34. The device of claim 33, further comprising a propellant
activator, the propellant activator positioned proximate the
propellant and configured to activate the propellant.
35. The device of claim 34, wherein the housing is configured to be
worn by a patient.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application No. 62/505,457, filed May 12, 2017, entitled "Systems
and Methods for Wearable Emergency Drug Injection Devices," and to
U.S. Provisional Application No. 62/444,237, filed Jan. 9, 2017,
entitled "Electronically-Actuated Drug Delivery System," which are
both hereby incorporated by reference in their entirety herein.
FIELD
[0002] The present application generally relates to drug injection
devices, and more specifically relates to systems and methods for
wearable emergency drug injection devices
BACKGROUND
[0003] People with certain medical conditions may require doses of
medication in response to certain physiological conditions. For
example, a diabetic may monitor her blood sugar and, if it gets too
high, inject insulin to help lower the blood sugar levels.
Conversely, she may eat some food if her blood sugar gets too low.
Another example is a person with an allergy to peanuts or insect
stings that experiences anaphylaxis as a result of contact with the
allergen. To respond to the anaphylaxis, the person may inject
herself with epinephrine, such as with an off-the-shelf epinephrine
injector, e.g., an EpiPen.RTM..
SUMMARY
[0004] Various examples are described for systems and methods for
wearable emergency drug injection devices. For example, one
disclosed example device includes a housing defining at least a
first chamber and a second chamber; an injector disposed within the
housing and comprising: a hollow needle coupled to a first piston,
the first piston disposed and translatable within the first chamber
towards a first end of the first chamber, the first piston defining
a void intersecting a hollow portion of the needle; a first
propellant disposed within the first chamber and positioned to
force the first piston towards the first end of the first chamber
in response to activation of the first propellant; a dispenser
disposed within the housing and comprising: a second piston
disposed and translatable within the second chamber towards a first
end of the second chamber; a second propellant disposed within the
second chamber and positioned to force the second piston towards
the first end of the second chamber in response to activation of
the second propellant; and wherein translation of the first piston
to the first end of the first chamber exposes the void to the first
end of the second chamber.
[0005] One disclosed example method includes receiving an
activation signal; in response to receiving the activation signal,
activating a first propellant of an injection device to force a
first piston towards a first end of a first chamber, the injection
device comprising a hollow needle coupled to the first piston, the
first piston disposed and translatable within the first chamber
towards the first end of the first chamber, the first piston
defining a void intersecting a hollow portion of the needle;
subsequent to activating the first propellant, activating a second
propellant of the injection device to force the second piston
towards the first end of the second chamber, an injectable
substance disposed within the second chamber; and wherein
translation of the first piston to the first end of the first
chamber exposes the void to the first end of the second
chamber.
[0006] These illustrative examples are mentioned not to limit or
define the scope of this disclosure, but rather to provide examples
to aid understanding thereof. Illustrative examples are discussed
in the Detailed Description, which provides further description.
Advantages offered by various examples may be further understood by
examining this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The accompanying drawings, which are incorporated into and
constitute a part of this specification, illustrate one or more
certain examples and, together with the description of the example,
serve to explain the principles and implementations of the certain
examples.
[0008] FIGS. 1A-1D show an example wearable emergency drug
injection device according to this disclosure;
[0009] FIG. 2 shows an example system for wearable emergency drug
injection devices according to this disclosure;
[0010] FIGS. 3A-3G show an example wearable emergency drug
injection device according to this disclosure;
[0011] FIGS. 4A-4B and show example wearable emergency drug
injection device according to this disclosure;
[0012] FIGS. 5A-5B show an example wearable emergency drug
injection device according to this disclosure;
[0013] FIGS. 6A-6D show an example wearable emergency drug
injection device according to this disclosure;
[0014] FIGS. 7A-7B show an example wearable emergency drug
injection device according to this disclosure;
[0015] FIG. 8 shows an example wearable emergency drug injection
device according to this disclosure; and
[0016] FIG. 9 shows an example method for using a wearable
emergency drug injection device according to this disclosure.
DETAILED DESCRIPTION
[0017] Examples are described herein in the context of systems and
methods for wearable emergency drug injection devices. Those of
ordinary skill in the art will realize that the following
description is illustrative only and is not intended to be in any
way limiting. Reference will now be made in detail to
implementations of examples as illustrated in the accompanying
drawings. The same reference indicators will be used throughout the
drawings and the following description to refer to the same or like
items.
[0018] In the interest of clarity, not all of the routine features
of the examples described herein are shown and described. It will,
of course, be appreciated that in the development of any such
actual implementation, numerous implementation-specific decisions
must be made in order to achieve the developer's specific goals,
such as compliance with application- and business-related
constraints, and that these specific goals will vary from one
implementation to another and from one developer to another.
[0019] A person with a medical condition, such as diabetes or a
severe allergy to a substance, may use a wearable emergency drug
injection device according to this disclosure. In this example, the
person (also the "wearer") obtains the device, which is
approximately an inch wide, one and a half inches long, and half an
inch tall. The example device has two halves that clip together to
form the completed device.
[0020] One half, the disposable half, has components to store and
deliver a dose of an injectable substance, e.g., 1 milligram ("mg")
of glucagon powder and 1 milliliter ("ml") of an activation
solution that when mixed with the glucagon, activates the glucagon
to enable it to be metabolized by the wearer. Specifically, the
disposable half has two chambers. Each chamber has a piston that
initially is at one of the chamber. Within each chamber is one of
the two substances--the glucagon powder or the activation solution.
In addition, one of the two chambers has a component with a hollow
needle attached to it, which enables injection of the substances
into the wearer. Behind each of the pistons is a small charge that,
when activated, generates pressure behind the piston to force the
piston to the opposite end of the chamber, thereby expelling the
contents of the respective chamber.
[0021] The second half of the device, the reusable half in this
example, includes circuitry to receive a command to inject the
injectable substance and to activate the two small charges in
response to the command. For example, the wearer could press a
button on the reusable half to trigger the circuitry to activate
the charges. Alternatively, the circuitry could receive the command
wirelessly from another device, such as the wearer's smartphone,
CGM, insulin pump, etc.
[0022] In this example, the circuitry is configured to activate the
two charges in sequence. The first charge forces the piston towards
the end of the chamber that has the needle, which forces the needle
to extend out of the device and bend towards and into the wearer's
skin. As mentioned above, the needle is hollow and is exposed to a
small void or cavity within the piston, in which the glucagon has
been deposited. Thus, after the first charge is activated, the
needle is inserted into the patient, but the glucagon powder
remains within the void in the piston.
[0023] After the first charge has activated, the second charge is
activated, which forces the piston in the second chamber towards to
opposite end of the chamber. The piston's movement forces the
activation solution out of the second chamber, through the void in
the first piston, where it mixes with the glucagon powder, and then
into the hollow needle and ultimately into the patient. Thus, a
dose of glucagon is delivered to the patient in response to, for
example, a continuous glucose monitor ("CGM") detecting a low
glucose level and transmitting a signal to the device.
[0024] This illustrative example is given to introduce the reader
to the general subject matter discussed herein and the disclosure
is not limited to this example. The following sections describe
various additional non-limiting examples and examples of systems
and methods for wearable emergency drug injection devices.
[0025] Referring now to FIG. 1A, FIG. 1A shows an example wearable
emergency drug injection device 100. As can be seen in FIG. 1A, the
example device 100 has two portions 110, 120 that are connected,
but are separable from each other. The first portion 110 has
electronic components within it, which are described in more detail
with respect to FIGS. 1B and 1C, and an antenna 118 to receive
wireless signals. The first portion 110 in this example is
separable from the second portion 120 to allow for re-use of the
electronics, while the second portion can be discarded after it has
been used.
[0026] The second portion 120 has two chambers that can be used to
store injectable material(s), as well as a hollow needle 152 and a
needle cap 150 that can be used to drive the needle 152 through the
needle guide 154 and into a person's skin. In this example, because
the needle 152 is hollow, injectable material(s) can be forced out
of one or both chambers, through the needle, and into the
wearer.
[0027] The example device shown in FIG. 1A is designed to be worn
flush against a wearer's body, such as on an upper arm or torso.
The needle 152, as shown in FIG. 1A, is oriented to extend parallel
to the wearer's skin; however, the needle guide 154 defines a
curved path that forces the needle 152 to bend towards the wearer's
skin at an angle departing from its initial orientation by
approximately 30 degrees in this example. Thus, the needle 150, in
this example, is formed of a flexible materials, such as a
nickel-titanium alloy (e.g., Nitinol), to allow the needle 152 to
bend at angles of up to 30 degrees (or more) without breaking or
obstructing the fluid path through the interior of the needle 152.
In addition, the needle 152 in this example is a 22-gauge needle.
Such a needle size may provide a diameter suitable for injecting
fluid into the wearer while having a diameter that causes a
tolerable amount of discomfort to the wearer; however, other
suitable needle diameters may be employed.
[0028] With respect to description of length, width, and height,
the height of the device 100 shown in FIG. 1A refers to how far the
device extends above the wearer's skin when worn as described
above. The length and width, by contrast, refer to the dimensions
of the perimeter of the device 100 shown in FIG. 1A.
[0029] Referring now to FIG. 1B, FIG. 1B shows a more detailed view
of the interior of the first and second portions 110, 120 of the
device 100. As discussed above, the second portion 120 defines two
chambers 122, 124. Within each chamber 122, 124 is a piston 132,
134 which are initially positioned at one end of the respective
chamber opposite an opening. Thus, when the pistons 132, 134 move,
the contents of the corresponding chamber 122, 124 are expelled
through their respective opening.
[0030] The pistons 132, 134 are sized to have approximately the
same cross-sectional area as the corresponding chamber 122, 124 to
prevent the contents of the chamber 122, 124 from sliding around
the piston or, as will be described above, gas pressure generated
behind the piston from being dissipated by escaping around the
piston 132, 134. In addition, in some examples, one or more of the
pistons 132, 134 may have one or more ring seals attached around
the perimeter of the piston 132, 134 to prevent such leakage of
material or gasses past the piston 132, 134.
[0031] A propellant 142, 144 is disposed behind each piston 132,
134. When one of the propellants 142, 144 is activated, it
generates pressure within the portion of the chamber behind the
piston 132, 134, thereby forcing the piston 132, 134 towards the
opposite end of the chamber.
[0032] In this example, each propellant 142, 144 comprises a
nitrocellulose material, and propellant 1 (142) has a
faster-burning nitrocellulose material than propellant 2 (144). For
example, propellant 1 (142) in this example is a nitrocellulose in
a cotton-based format, while propellant 2 (144) in this example is
a nitrocellulose in a paper-based format. Selection of an
appropriate propellant may be made based on the contents of the
chamber.
[0033] For example, chamber 1 may have no injectable material in
it, or may have an amount of an injectable powder or liquid, and
thus may provide a mechanism for forcing the needle cap 150 and
needle 152 downwards, thereby injecting the needle into the
wearer's skin. In such an example, a faster-burning propellant may
be used as concerns about over-pressurizing the chamber 122 may be
reduced. In contrast, in this example, chamber 2 has an injectable
fluid. Thus, a slower-burning or slower-acting propellant may be
desired to allow time for the fluid to be expelled from the chamber
122 without over-pressurizing the chamber walls. In addition,
selection of propellants may be made based on a desired firing
sequence, a time to deliver a full dose of material to the wearer,
or a time between insertion and retraction of the needle 152.
[0034] In some examples, a quantity of propellant for a chamber may
be made up of multiple discrete propellant elements, each of which
may be individually activatable. Thus, to activate the propellant,
each individual propellant element may be activated separately or
in combination. In examples where the individual propellant element
is activated separately, a firing sequence may be employed to
activate the propellant elements to create a desired pressure curve
over time. For example, the propellant elements may be activated at
regular intervals, e.g., one ever half-second, or several may be
activated initially to create a high pressure, e.g., to drive a
needle into the wearer's skin, followed by successive activation of
the remaining propellant elements to slowly and steadily inject a
substance into the wearer.
[0035] To enable the injectable material to move from the
chamber(s) into the wearer, as discussed above, the needle 152 is
hollow. In addition, a fluid path 126 is defined between the two
chambers to allow injectable material to move from chamber 2 (124)
through the fluid path 126 over the needle cap 150 and into the
needle 150. And while it is referred to as a "fluid" path 126, it
can allow solid (e.g., powders) or gaseous materials to flow as
well. In addition, piston 1 (132) also defines a void that, after
piston 1 (132) has been driven to the opposite end of the chamber
122, the void is exposed to the fluid path as well as the hollow
portion of the needle. Thus, the combination of the fluid path 126,
the void within piston 1 (132), and the hollow needle 152 provide a
path for an injectable material to be expelled from the chamber(s)
122, 124 and into the wearer.
[0036] In addition, in this example, a pair of springs 156a-b is
coupled to the needle cap to enable retraction of the needle 152.
Thus, after the injectable substance has been expelled out of the
chamber(s) and in to the wearer, the device 100 may retract the
needle 152, via the springs 156a-b in this example. For example,
the pressure generated by propellant 1 (142) may initially overcome
the spring force, but as the pressure dissipates, e.g., via an
exhaust port, the springs 156a-b may ultimately overcome the
pressure and retract the needle 152. In other examples, other
needle retraction mechanisms may be employed, such as another
propellant charge located beneath the needle cap.
[0037] While the second portion 120 includes the injectable
material(s) and the mechanisms for inserting the needle 152 into
the wearer and for storing and expelling the injectable
material(s), the first portion 110 includes components to receive a
command (or commands) to activate the propellant and inject the
injectable material(s). In this example, the first portion 110
includes a firing circuit 112, a battery 114 or other electrical
power source or connection, a wireless receiver 116, and an antenna
118. To activate the propellants 142, 144 and inject the injectable
material into the wearer, in this example, a command is received
via the antenna 118 and the receiver 116 from a remote device, such
as the wearer's smartphone or a biosensor (e.g., a CGM), and is
provided to the firing circuit 112. In response to receiving the
command, the firing circuit 112 activates the propellants 142, 144
using power supplied by the battery 114.
[0038] In this example, the propellants 142, 144 are activated by
an electrical discharge. To supply the electrical discharge, the
firing circuit 112, prior to receiving the command in this example,
charges two capacitors using the battery 114. Upon receiving the
command from the receiver 116, the firing circuit 112 couples the
capacitors, in sequence, to electrical leads in contact with the
respective propellant 142, 144, thereby allowing them to discharge
and activate the corresponding propellant 142, 144.
[0039] An example of the firing circuit 112 is shown in FIG. 1C. As
described above, the firing circuit 112 in this example includes
capacitors selectably connected to a corresponding propellant
charge. By closing a corresponding switch, e.g., a transistor, the
capacitor's charge is delivered to the propellant 142, 144,
activating it. For example, the charge may be applied to a resistor
in contact with the propellant. The charge may cause the resistor
to generate heat, which ignites the propellant.
[0040] In addition to the firing circuit 112, other electronic
components may be provided within the first portion 110 as well,
such as battery charging circuitry 113, which may a wired
connection or a wireless power antenna and rectifier, power and
filtering circuitry 115, and a microcontroller 117, e.g., an ASIC
defined on a field-programmable gate array ("FPGA"). Still further
electronic components may be included within the first portion 110
to enable various features according to this disclosure.
[0041] While this example employs a wireless command to activate
the firing circuit 112, in some examples, the device 100 may
instead have a wired connection to another device, e.g., a
biosensor, or may have a button or other wearer manipulatable
device ("manipulandum") to activate the firing circuit 112.
[0042] Further, while the example shown in FIG. 1A-1B has two
portions 110, 120 that may be decoupled from each other, in some
examples, the device 100 may be formed from a single portion that
includes the components described above, or other components
according to this disclosure. Thus, rather than providing a second
portion 120 that is disposable and first portion 110 that is
reusable, the entire device may be discarded.
[0043] Referring now to FIG. 1D, FIG. 1D shows the device 100 after
the propellants 142, 144 have been activated and the pistons 132,
134 driven to the opposite end of the chambers 122, 124. Piston 1
(132) has driven needle cap 150 and needle 152 away from the bottom
of the first chamber 122. The needle 152 has travelled through the
needle guide 154, where it was bent towards the wearer's skin. The
second piston 134 has expelled the contents of chamber 2 through
the fluid path 126, the void in piston 1 (132), and the needle 152
into the wearer.
[0044] While in this example, piston 2 (134) has been driven the
full length of chamber 2, in some examples, the piston 134 may only
be driven part of the length of the chamber. For example,
propellant sufficient to only drive the piston partway through a
chamber, or one or more physical obstructions may be disposed
within the chamber 124, or formed in the walls of the chamber 124
to prevent the piston from travelling the full length of the
chamber. Such a feature may be desirable to allow for a greater
quantity of injectable material to be disposed within the chamber
124 than is to be dispensed in a single dose. For example the
chamber 124 may store 1 ml of epinephrine, but one or more
obstructions may permit the piston to expel only, for example, 0.3
ml of epinephrine. Such features may enable a more uniform
manufacturing process or help ensure sufficient injectable material
is injected, even in the event of a partial failure of the device,
e.g., the propellant 144 only partially activates.
[0045] While the example device 100 shown in FIGS. 1A-1D has two
chambers, any suitable number of chambers may be employed. For
example, an example wearable emergency drug injection device may
only have a single chamber, such as chamber 1 shown in FIG. 1B. Or
a second portion 120 may have more than two chambers, each
configured with a piston and propellant. Further, the device may
include multiple needles to enable delivery of multiple doses, or
doses of different types of injectable materials based on a
received command.
[0046] Referring now to FIG. 2, FIG. 2 shows an example system for
a wearable emergency drug injection device. In this example, the
device 100 shown in FIGS. 1A-1D receives a wireless command from
remote device 200. The remote device 200, as described above, may
be any suitable device with a wireless transmitter, such as a
smartphone, smartwatch, blood pressure sensor, CGM, etc. Such
remote devices may be handheld or wearable devices or larger
devices, such one or more sensing systems as may be found in a
hospital or other medical office. Suitable wireless communication
mechanisms include Bluetooth.RTM., Bluetooth.RTM. low-energy
("BLE"), WiFi, near-field communications ("NFC"), etc.
[0047] In one example, the remote device 200 is a CGM 200 that
senses and stores glucose levels over time for the wearer. The
glucose levels may be accessed wirelessly by various devices, such
as the wearer's smartphone, an insulin pump, or example wearable
emergency drug injection devices according to this disclosure. In
this example, the CGM 200 is configured with a glucose level
threshold, below which the wearer is experiencing a hypoglycemic
event. The CGM 200 may periodically measure the wearer's glucose
levels and compare them to the glucose level threshold. If a
measured glucose level (or several consecutive measured glucose
levels) falls below the glucose level threshold, the CGM 200 may
determine a hypoglycemic event. In this example, the CGM 200 may
issue an alert to the wearer, such as by transmitting a signal to
the wearer's insulin pump to trigger an audible alarm. The CGM 200
may also transmit a signal to the device 100 to cause it to deliver
a dose of glucagon to the wearer.
[0048] In this example, the CGM 200 first transmits a signal to the
wearer's insulin pump, if the wearer has one, and continues to
monitor the wearer's glucose levels to detect whether they rise
above the glucose level threshold. If the glucose levels rise above
the glucose level threshold, it may indicate that the wearer has
eaten some food and the hypoglycemic event has passed. However, if
after a predetermined period of time, e.g., 5 minutes, the
hypoglycemic event continues or worsens, the CGM 200 may then
determine intervention is needed and transmit the signal to the
device 100 to cause a dose of glucagon to be injected into the
wearer. Such an example may be desirable as it may allow the wearer
to raise their glucose levels, even if they are unresponsive, e.g.,
due to being asleep or unconscious. And while this example relates
to a hypoglycemic event and a CGM, other biosensors may be employed
as well or instead.
[0049] For example, blood pressure, ECG, blood oxygen, etc.
biosensors may be employed in some examples to detect medical
events, such as anaphylaxis, etc., which may then trigger the
biosensor, or another device such as a smartphone, to transmit a
signal to the device 100 to cause an injectable material, e.g.,
epinephrine, naloxone, etc., to be injected into the wearer. Thus,
different medical events may be addressed or mitigated
automatically via the combination of the remote device 200 and the
example wearable emergency drug injection device 100, which may
address an emergency condition or may allow time for a full medical
response to occur, if needed.
[0050] Referring now to FIGS. 3A-3G, these figures show different
views of an example wearable emergency drug injection device 300.
Referring to FIG. 3A, the wearable emergency drug injection device
300 (or device 300) includes two portions, an electronics portion
310 and an injection portion 320. As can be seen, the electronics
portion 310 is releasably coupled to the injection portion 320 by
two clips 311a-b. The clips 311a-b engage with the injection
portion 320 to releasably secure the two portions 310, 320
together.
[0051] With respect to the injection portion 320, it defines two
chambers 322, 324, within each of which is a corresponding piston
332, 334. In addition, the injection portion 320 defines a fluid
path 326 that can provide a fluid coupling between chamber 2 (324)
and a void (shown in FIG. 3D (329)) defined in piston 1 (332) after
piston 1 (332) has been driven to the opposite end of the chamber
322. FIG. 3A shows the device 300 prior to injecting injectable
material, thus, the pistons 332, 334 are positioned at one end of
the chamber. Each chamber also includes propellant 342 positioned
behind the corresponding piston 332, 334, though note that
propellant 344 behind piston 2 (334) is not visible in this
figure.
[0052] As discussed above, one or both of the chambers may have an
injectable substance contained within it. For example, suitable
injectable substances may include epinephrine, naloxone, glucagon
or a glucagon activation solution, or other drugs or chemicals.
[0053] Each of the chambers 322, 324 has an exhaust vent 328a-b to
allow gasses generated by the propellant 342, 344 to escape from
the respective chamber 322, 324. And while in this example, the
exhaust vents 328a-b vent gasses directly into the wearer's
environment, in some examples, one or more exhaust vents 328a-b may
vent exhaust gasses into a needle retraction mechanism.
[0054] The injection portion also includes a needle cap 350 and a
hollow needle 352 that are arranged within the fluid path 326, and
a needle guide 354. The needle cap 350 provides two functions in
this example device. First, the needle cap 350 provides a coupling
surface and way to transfer force from piston 1 (332) to the needle
350 to drive the needle 350 through a path in the needle guide 354
and into the wearer's skin. The needle cap 350 also provides a
fluid barrier between the fluid path 326 and chamber 1 (322) prior
to activation of the propellant 342 behind piston 1 (332).
[0055] The needle 352 in this example is hollow to allow injectable
material to flow through the needle 352 and into the wearer. In
addition, the needle 352 is constructed from a flexible material,
such as a suitable plastic or metallic material, such as Nitinol.
The needle 352 in this example is sufficiently flexible that it can
bend at an angle of between 30 to 45 degrees without permanently
deforming and while maintaining a fluid path through the
needle.
[0056] The needle guide 354 is formed in or coupled to the
injection portion 320 to provide a path through which the needle
352 is forced to bend at an angle towards the wearer's skin Thus,
as the needle 352 is driven by the piston 332, it moves into and
through the path formed in the needle guide 354 and bends towards
the wearer's skin.
[0057] As discussed above with respect to FIGS. 1A-1D, while
example devices according to this disclosure may include needle
retraction mechanisms, this example device 100 does not include
such a feature. However, as discussed above, any suitable needle
retraction mechanism, including springs or an exhaust gas
retraction arrangement may be employed according to various
examples.
[0058] Referring now to the electronics portion 310, the
electronics portion 310 houses one or more electronic circuits to
receive an activation signal, such as wirelessly as described above
with respect to FIGS. 1A-1D and 2, or from a wearer interaction
with a manipulandum. In this example, the electronics portion 310
includes the example electronic circuits discussed above with
respect to FIGS. 1C and 1D, which may be used to activate the
device's propellant 342,344.
[0059] Referring now to FIG. 3B, FIG. 3B shows a view of the device
300 of FIG. 3A after the propellant 342, 344 has been activated and
the pistons 332, 334 have been driven to the opposite end of their
respective chambers 322, 324. In this example, propellant 342 was
activated first, which forced piston 1 (332) to the opposite end of
chamber 1 (322) and against the needle cap 350, thereby forcing the
needle cap 350 and needle 352 away from the chamber 322 and the
needle 352 through the needle guide 354 and into the wearer's
skin.
[0060] After piston 1 (332) completed its movement, the second
propellant 344 was activated, driving piston 2 (334) to the
opposite end of chamber 2 (324), thereby forcing any injectable
substance in chamber 2 (324) through the fluid path 326, the void
329 in piston 1 (332), and the needle 352 into the wearer. In this
example, as discussed above, piston 1 (332) also defines a void
through which the injectable substance from chamber 2 flows,
thereby enabling the injectable substance to mix with another
injectable substance prior to flowing through the needle 352 and
into the wearer. Such a configuration may enable the use of
substances that may be activated by mixing them prior to injection
into the wearer.
[0061] Referring now to FIGS. 3C and 3D, FIGS. 3C and 3D show
perspective views of the device 300 of FIGS. 3A-3B. These
perspectives show the shape of the needle guide and the bend formed
in the needle 352 as it travels through the needle guide 354.
[0062] Referring now to FIG. 3E, FIG. 3E shows the components
corresponding to chamber 1 (322) discussed above with respect to
FIG. 3A. As can be seen, the piston defines a void 329 with a small
hole to provide a fluid path through the void 329 and into the
needle 352. In this example, the needle 352 extends into the
chamber 322 and couples to the piston 332 such that the piston 332
directly drives the needle 352. However, in some examples, the
needle 352 may not extend into the chamber 322. In some such
examples, the hole formed in the piston 332 may be aligned with the
needle 352 to create a fluid path through the void 329 to the
needle 352 after piston 1 (332) has been driven into contact with
the needle cap 150. Further, this figure illustrates piston seals
333a-b that create a seal between the piston 332 and the chamber
wall to help prevent exhaust gasses from the propellant 342 from
passing around the piston 332 and into the chamber 322. Similar
seals may be provided on piston 2 (334) as well.
[0063] FIG. 3F shows a perspective view of the device 300 of FIGS.
3A-3B after piston 1 (332) has been driven to the opposite end of
the chamber 322 following activation of the propellant 342. As can
be seen, the void 329 in piston 1 (332) is exposed to the fluid
path 326 and allows injectable material to be expelled from chamber
2 (324) through the fluid path 326 and void 329 into the needle
352, and subsequently into the wearer.
[0064] FIG. 3G shows a close-up perspective view of the clips
311a-b used to secure the electronics portion 310 to the injection
portion 320.
[0065] Referring now to FIGS. 4A-4B, these figures show a further
example wearable emergency drug injection device according to this
disclosure. In this example, only the injection portion 420 of the
device is shown. The injection portion 420 shown in FIG. 4A
illustrates the device before the propellant has been activated,
while FIG. 4B shows the device after the propellant behind piston 1
(432) has been activated.
[0066] The injection portion 420 defines two chambers 422, 424,
each of which has a piston 432, 434 generally as described above,
and each chamber has an exhaust vent 428a-b defined in the chamber
wall to allow combustion gasses to escape the respective chamber
422, 424. In addition, the injection portion 420 defines a fluid
path 426 that provides a fluid coupling between chamber 2 (424) and
the needle 452 after the first piston 432 has been driven to the
opposite end of the chamber 422. The injection portion 420 also
includes a needle guide 454, which as discussed above, causes the
needle 452 to bend as it traverses the needle guide 454.
[0067] Referring now to FIGS. 5A-5B, FIG. 5A shows another example
of an injection portion 500 of an example wearable emergency drug
injection device. In this example, the injection portion 500
includes a needle assembly 510 and a fluid cartridge 520 that are
formed separately, but may be coupled together via one or more tabs
512 or one or more clasps 530a-b The example 500 shown in FIGS.
5A-5B includes both tabs 512 and clasps 530a-b. The tabs 512 engage
with corresponding slots 514 to couple the fluid cartridge 520 with
the needle assembly 510. The clasps 530a-b then engage with each of
the fluid cartridge 520 and needle assembly 510 to create the
injection portion of an example wearable emergency drug injection
device. FIG. 5B shows the injection portion 500 after it has been
fully assembled.
[0068] It should be appreciated that in some examples, the needle
assembly 510 may not be coupled to a separate fluid cartridge.
Instead, the example needle assembly 510 may be a stand-alone
injection portion with only a single chamber in which an injectable
material may be disposed. In one such example, activation of the
propellant behind a piston in the needle assembly 510 may both
force a needle into a wearer of the device, but may also force the
injectable material through the needle and into the wearer, thereby
obviating the need for a separate fluid cartridge 520.
[0069] Referring now to FIGS. 6A-6D, these figures show an example
injection portion 600 at different times during activation. FIG. 6A
shows the injection portion before it has been activated. The two
pistons 632, 634 are at rest at one end of the respective chamber
622, 624. The needle cap 650 seals a fluid port between the two
chambers 622, 624, and the needle 652 is entirely contained within
the injection portion 600.
[0070] Referring now to FIG. 6B, propellant behind piston 1 (632)
has been activated, which as driven piston 1 (632) across chamber 1
(622) into contact with the needle cap 650. This movement has
forced the needle 652 through the needle guide 654, which bends the
needle 652. The propellant behind piston 2 (634) has not yet been
activated at this point.
[0071] Referring now to FIG. 6C, piston 1 (632) has continued to
traverse chamber 1 and has driven needle cap 650 against the needle
guide 654, thereby unsealing the fluid port between the two
chambers 622, 624. An opening in piston 1 (632) aligns with the
fluid port, providing a fluid path from chamber 2 (624) through the
fluid port, the void in piston 1 (632) and into the needle 652. At
this time, however, the propellant behind piston 2 (634) has not
yet been activated, thus the contents of chamber 2 (624) have not
yet been forced through the fluid port by piston 2 (634).
[0072] Referring now to FIG. 6D, the propellant behind piston 2
(634) has been activated, which drove piston 2 (634) to the
opposite end of chamber 2 (624), thereby forcing the contents of
chamber 2 (624) through the fluid port and ultimately into and
through the needle 652. Once piston 2 (634) has reached the far end
of chamber 2 (624), the injection portion 600 has completed its
operation, absent the use of a needle retraction mechanism, such as
a spring or other biasing material or element.
[0073] Referring now to FIGS. 7A-7B, FIG. 7A shows an example
wearable emergency drug injection device 700. In this example, the
device 700 includes five separate chambers 722a-e, each having its
own respective piston 732a-e and a corresponding propellant 742a-e.
Each chamber 722a-e is coupled to a fluid path 726 which enables
material from the respective chambers to be expelled from the
chamber, through an opening in the third piston 732c and the hollow
needle 752, thereby injecting the substance into the wearer. FIG.
7B shows an alternate perspective of the device 700. Example
devices having more than two chambers may be employed to dispense
larger amounts of material, or may allow doses to be dispensed over
time. For example, the third propellant 742c may be activated to
drive the third piston 732c across its chamber 722c, thereby
driving the needle 752 through the needle guide 754 and into the
wearer. One or more of the other propellant charges 742a,b,d,e may
be activated to expel a substance through the fluid path and the
needle into the wearer. Such charges may be activated in sequence
or only when a respective dose of material is needed. And while
this example includes five chambers, any suitable number of
chambers may be employed according to various examples.
[0074] Referring now to FIG. 8, FIG. 8 shows an example application
of a wearable emergency drug injection device 800 (or device 800)
according to this disclosure. As discussed above, the device 800
may be worn by a person to enable on-demand injection of an
injectable material in to the wearer. In this example, the device
800 is attached to an armband 810, which the wearer has wrapped
around their upper arm. Thus, if the device 800 is activated, such
as by a wireless signal from a remote device or based on wearer
interaction with a manipulandum on the device 800 or armband 810,
the device 800 may inject a needle into the wearer's arm and inject
the injectable material through the needle, thereby delivering a
dose of the injectable material.
[0075] While the example shown in FIG. 8 is of an armband
embodiment, other example wearable configurations are within the
scope of this disclosure. For example, the device 800 may be
attached to a wristband, or adhered to the wearer by a tape or an
adhesive applied to one side of the device 800. In some examples,
the features of the device may be incorporated into another
wearable device, such as an insulin pump, smartwatch, etc. Still
further configurations to enable wearing of the device 800 against
the wearer's skin are within the scope of this disclosure.
[0076] Referring now to FIG. 9, FIG. 9 shows an example method 900
for use of a wearable emergency drug injection device. The method
900 will be described with respect to the device 100 shown in FIG.
1 and the system shown in FIG. 2; however, any suitable device or
system according to this disclosure may be employed, such as the
example devices shown in FIGS. 3A-3G and 4A-4B.
[0077] At block 910, the device 100 receives an activation signal.
In this example, the device 100 receives a wireless signal from the
remote device 200 via a BLE wireless signal. To send the activation
signal, the remote device 200 may first establish a communications
connection with the device 100, such as by pairing with the device
using the BLE protocol and then authenticating itself to the device
100, e.g., by providing an encrypted communication comprising a
digital signature or certificate. After establishing communications
and authenticating itself to the device 100, the remote device 200
transmits an activation signal, which may comprise a command. And
while in this example, the remote device 200 authenticates itself
to the device 100, such a feature is not required. Instead, the
remote device 200 may simply transmit an activation signal, such as
by broadcasting an activation signal.
[0078] At block 920, in response to receiving the activation
signal, the device 100 activates propellant 1 (142) to force piston
1 (132) towards the opposite end of chamber 1 (122). In this
example, the firing circuit 112 closes a switch to discharge a
capacitor onto an electrical contact coupled to propellant 1 (142).
The electrical discharge from the capacitor ignites the propellant
142, which then burns or explodes. The piston 132 then traverses a
portion of the chamber 122 and forces the needle through the needle
guide 154. If a patient is wearing the device 100, the needle is
also injected into the wearer's skin.
[0079] In some examples, a series of activation signals may be
transmitted to propellant 1 (142). For example, propellant 1 (142)
may include multiple propellant components, each of which may be
individually activatable. By activating these propellant components
in sequence, a suitable pressure curve may be generated over
time.
[0080] At block 930, subsequent to activating the first propellant,
the device 100 activates propellant 2 (144) to force piston 2 (134)
towards the opposite end of the chamber 2 (124). In this example,
the firing circuit 112 closes a switch to discharge another
capacitor onto an electrical contact coupled to propellant 2 (144).
The electrical discharge from the capacitor ignites the propellant
144, which then burns or explodes, generally as described above
with respect to block 920. The piston 134 then traverses a portion
of the chamber 122 and forces the needle through the needle guide
154. If a patient is wearing the device 100, injectable material in
chambers 1 or 2 (122, 124) is dispensed into the wearer. As
discussed above with respect to block 920, in examples where
propellant 2 (144) includes multiple individually-activatable
propellant components, multiple actuation signals maybe transmitted
to activate the propellant components in sequence to create a
suitable pressure curve for driving the piston.
[0081] At block 940, the device 100 retracts the needle 152. In
this example, the springs 156a-b are compressed by the movement of
the needle cap 150. After sufficient gasses have been exhausted
from chamber 1 (122) and the chamber pressure drops below the force
exerted by the springs 156a-b, the needle 152 is retracted. Still
further needle retraction mechanisms may be employed in various
examples. It should be appreciated that block 940 is optional.
Thus, the needle 152 may not be automatically retracted by the
device 100. Instead, the wearer may manually retract the needle
152, or may remove the device 100 to withdraw the needle 152 from
their skin.
[0082] The foregoing description of some examples has been
presented only for the purpose of illustration and description and
is not intended to be exhaustive or to limit the disclosure to the
precise forms disclosed. Numerous modifications and adaptations
thereof will be apparent to those skilled in the art without
departing from the spirit and scope of the disclosure.
[0083] Reference herein to an example or implementation means that
a particular feature, structure, operation, or other characteristic
described in connection with the example may be included in at
least one implementation of the disclosure. The disclosure is not
restricted to the particular examples or implementations described
as such. The appearance of the phrases "in one example," "in an
example," "in one implementation," or "in an implementation," or
variations of the same in various places in the specification does
not necessarily refer to the same example or implementation. Any
particular feature, structure, operation, or other characteristic
described in this specification in relation to one example or
implementation may be combined with other features, structures,
operations, or other characteristics described in respect of any
other example or implementation.
[0084] Use herein of the word "or" is intended to cover inclusive
and exclusive OR conditions. In other words, A or B or C includes
any or all of the following alternative combinations as appropriate
for a particular usage: A alone; B alone; C alone; A and B only; A
and C only; B and C only; and A and B and C.
* * * * *