WEARABLE THERAPEUTIC DEVICE
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional
Application Serial No. 61/421,970 entitled "Wearable Therapeutic Device," filed
December 10, 2010 and to U.S. Provisional Application Serial No. 61/530,585
entitled "Wearable Therapeutic Device," filed September 2, 2011, each of which is
incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
At least one embodiment of the present invention relates generally to a
wearable therapeutic device, and more specifically, to a wearable therapeutic device
having electrodes configured to monitor or treat a subject.
2. DISCUSSION OF THE RELATED ART
Cardiac arrest and other health ailments are a major cause of death worldwide.
Various resuscitation efforts aim to maintain the body's circulatory and respiratory
systems during cardiac arrest in an attempt to save the life of the victim. The sooner
these resuscitation efforts begin, the better the victim's chances of survival. Health
care professionals also attempt to detect and prevent conditions conducive to cardiac
ailments by treating patients with drugs or by suggesting lifestyle changes. These
efforts are expensive and have a limited success rate, and cardiac arrest, among other
conditions, continues to claim the lives of victims.
SUMMARY OF THE INVENTION
Aspects and embodiments of the present invention are directed to a wearable
therapeutic device that is configured to be worn by a subject. The wearable
therapeutic device includes at least one electrode in, for example, a pocket of the
wearable therapeutic device. When properly positioned, a conductive surface of the
electrode can be disposed in the pocket to face the subject, proximate to the subject's
skin so that information (e.g., cardiac information) can be sensed or treatment (e.g., a
defibrillation shock) can be applied to the subject. A conductive thread can be sewn
into parts of the wearable therapeutic device, including parts of the pocket that are not
proximate to the subject's skin. A circuit can be formed when the conductive surface
of the electrode couples with the conductive thread. When this circuit is formed, the
conductive surface of the electrode is generally not proximate to the subject's skin,
and not in position to apply treatment. Based on the coupling of the conductive
surface of the electrode and the conductive thread, an alarm module can indicate that
the electrode is or is not properly positioned.
At least one aspect is directed to a wearable therapeutic device. The wearable
therapeutic device includes a garment, and the garment includes an electrode and a
conductive thread. A control unit is coupled to the conductive thread and identifies an
electrical connection between a conductive surface of the electrode and the
conductive thread, and an alarm module indicates infonnation about the positioning of
the electrode in the garment based on the electrical connection.
At least one other aspect is directed to a method of facilitating care of a
subject. The method provides a wearable therapeutic device that includes an
electrode and a conductive thread. The method also identifies an electrical connection
between a conductive surface of the electrode and the conductive thread. The method
provides a notification to indicate positioning infonnation of the electrode based on
the electrical connection.
At least one other aspect is directed to and method that includes providing a
wearable therapeutic device including a garment. The garment houses an electrode
and includes conductive thread. The wearable therapeutic device includes a control
unit coupled to the conductive thread. The control unit identifies an electrical
connection between the electrode and the conductive thread. An alarm module
indicates positioning information of the electrode in the garment based on the
electrical connection.
The electrode can be a therapy electrode or a sensing electrode. In some
embodiments, the garment includes a pocket that houses the electrode. The pocket
can have a first lateral side and a second lateral side, with the conductive thread sewn
into the first lateral side or into the second lateral side. In one embodiment, one
lateral side includes a conductive mesh and the other includes the conductive thread.
The first lateral side can be proximate to a subject, and the second lateral side can be
distal to the subject, with the conductive thread disposed in the second lateral side of
the pocket.
In one embodiment, a conductive element can be included in the garment. A
connector can couple the conductive thread with the conductive element. The control
unit is further can detect a current path that includes the conductive thread, the
conductive surface of the electrode, and the conductive element. In one embodiment,
the garment includes a belt, with a conductive element included in the belt. A
connector can couple the conductive thread with the conductive element to form
electrical connection between the conductive surface of the electrode and the
conductive element. The connector may include a snap. The conductive element can
connect with the conductive thread at one or more points of the conductive thread.
In one embodiment, the conductive thread forms a stitched pattern in the
garment. The conductive thread can also form a stitched pattern including at least two
substantially parallel stitched lines, or a pattern in at least one of a quadrilateral shape,
a polygonal shape, an oblong shape, a circular shape, an oval shape, a round shape,
and a triangular shape. In one embodiment, the conductive thread forms part of an
electrical connection with the electrode.
In one embodiment, the alarm module can notify a subject wearing the
wearable therapeutic device, or a health care provider, that the electrode is properly or
improperly positioned. A monitor can display an indication that the electrode is
properly or improperly positioned.
In some embodiments, the electrode can be housed in a pocket of the garment,
and the conductive thread can be woven into the pocket. The electrode can be
determined to be positioned with a conductive surface facing away from a subject. A
closed circuit that includes a conductive surface of the electrode and the conductive
thread can be detected, and improper positioning of the electrode can be determined.
In one embodiment, the wearable therapeutic device includes a conductive element,
and a current path that includes the conductive thread, the conductive surface of the
electrode, and the conductive element can be detected. In one embodiment, the
conductive thread can be coupled with the conductive element.
In one embodiment, instructions can be provided to operate the wearable
therapeutic device. The instructions can include at least one instruction directing a
subject to position a conductive surface of the electrode proximate to the subject. The
wearable therapeutic device can include a garment with a pocket to house the
electrode. The pocket can be formed at least in part from a conductive mesh, and
instructions can be provided to position a conductive surface of the electrode facing
the conductive mesh. Instructions can also be provided to position a conductive
surface of the electrode facing away from the conductive thread.
Other aspects and embodiments are discussed in detail below. The foregoing
information and the following detailed description include illustrative examples of
various aspects and embodiments, and are intended to provide an overview or
framework for understanding the nature and character of the claimed aspects and
embodiments. The drawings provide illustration and a further understanding of the
various aspects and embodiments, and are incorporated in and constitute a part of this
specification. The drawings, together with the remainder of the specification, serve to
describe and explain the claimed aspects and embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are not intended to be drawn to scale. In the
drawings, each identical or nearly identical component that is illustrated in various
figures is represented by a like numeral. For purposes of clarity, not every component
may be labeled in every drawing. In the drawings:
Figure 1 is a block diagram depicting a wearable therapeutic device in
accordance with an embodiment;
Figure 2 is a schematic diagram depicting a wearable therapeutic device in
accordance with an embodiment;
Figure 3 is a diagram depicting a portion of a wearable therapeutic device with
conductive thread sewn into a pocket in accordance with an embodiment;
Figure 4 is a diagram depicting a portion of a wearable therapeutic device with
conductive thread sewn into a pocket in accordance with an embodiment;
Figure 5 is a diagram depicting a portion of a wearable therapeutic device with
conductive thread sewn into a pocket in accordance with an embodiment;
Figure 6 is a cross sectional view of a wearable therapeutic device with an
electrode disposed in a pocket of the wearable therapeutic device in accordance with
an embodiment;
Figure 7 is a cross sectional view of a wearable therapeutic device with an
electrode disposed in a pocket of the wearable therapeutic device in accordance with
an embodiment; and
Figure 8 is a flowchart depicting a method of facilitating care of a subject in
accordance with an embodiment.
DETAILED DESCRIPTION
The systems and methods described herein are not limited in their application
to the details of construction and the arrangement of components set forth in the
description or illustrated in the drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in various ways. Also,
the phraseology and terminology used herein is for the purpose of description and
should not be regarded as limiting. The use of "including" "comprising" "having"
"containing" "involving" and variations thereof herein, is meant to encompass the
items listed thereafter, equivalents thereof, and additional items, as well as alternate
embodiments consisting of the items listed thereafter exclusively.
Various aspects and embodiments are directed to a wearable therapeutic
device that can be worn by a subject. The wearable therapeutic device can include a
garment with at least one pocket to house at least one electrode. When the electrode
is properly positioned, a conductive surface of the electrode faces the subject and
directly or indirectly contacts the subject's skin. When properly positioned, the
electrode can apply therapy, such as a defibrillation shock, to the subject. Due, for
example, to subject motion or improper installation by the subject, a health care
provider or manufacturer, the electrode can become improperly positioned, so that its
conductive surface does not face the subject. When the electrode is improperly
positioned, its conductive surface can contact a conductive thread included in the
garment. This can form an electrical connection, and detection of this electrical
connection can indicate that the electrode is improperly positioned to sense
information about or apply therapy to the subject. An alarm module can provide a
notification that the electrode is properly or improperly positioned. Corrective action
can be taken to properly position the electrode.
Figure 1 is a block diagram of wearable therapeutic device 100 in accordance
with an embodiment. In one embodiment, wearable therapeutic device 100 includes
the wearable therapeutic device described in commonly owned U.S. Patent
Application Serial No. 13/109,079, titled "Wearable Therapeutic Device," filed on
May 17, 2011, which is incorporated by reference herein in its entirety. The
referenced application generally describes a wearable therapeutic device.
Wearable therapeutic device 100 can include at least one garment 105 in the
shape of a vest or shirt. Garment 105 may also include at least one belt 110. Belt 110
may be worn about a subject's waist, at a higher location about or across the subject's
chest, or at other locations between the subject's waist and shoulders. Components of
wearable therapeutic device 100, including garment 105, can be worn under, over, or
partially under and partially over a subject's clothes. In one embodiment, garment
105 is formed from breathable fabric. Garment 105 may also be stretchable.
In one embodiment, wearable therapeutic device 100 includes at least one of
the following elements: garment 105, belt 110, external defibrillator 115, alarm
module 120, monitor 125, control unit 130, sensing electrode 135, therapy electrode
140, strap 145, conductive thread 150, conductive element 155, and pocket 160. In
one embodiment, at least one of external defibrillator 115, alarm module 120, monitor
125, control unit 130, sensing electrode 135, therapy electrode 140, conductive thread
150, conductive element 155, and pocket 160 are included in or attached to garment
105, belt 110 or strap 145. For example, wearable therapeutic device 100 components
can be fitted into open or closed pockets 160, or otherwise attached to garment 105
via buckles, hook and loop fasteners, holsters, loops, pouches or sleeves that form
part of belt 110 or strap 145. These elements may also be integrated into belt 110 or
strap 145, and these elements may be a permanent part of belt 110 or strap 145, or
releasable from belt 110 or strap 145. Garment 105 may include a series of belts 110
or straps 145, and need not constitute an article of clothing. Wearable therapeutic
device 100 may include one, more than one, or all of the above mentioned elements,
as well as additional elements such as at least one power supply to provide power to
control unit 130, external defibrillator 115, alarm module 120, monitor 125, sensing
electrodes 135, or therapy electrodes 140.
External defibrillator 115 can be included as part of wearable therapeutic
device 100. For example, external defibrillator 115 can be included in garment 105,
pocket 160, attached to strap 145, or disposed in belt 110. In one embodiment,
external defibrillator 115 is electrically coupled to therapy electrode 140. Wearable
therapeutic device 100 may include at least one receptacle having a conductive fluid
encapsulated therein and housed in garment 105. For example, the receptacle can be
disposed in belt 110 or strap 145, proximate to at least one of sensing electrode 135
and therapy electrode 140. In one embodiment, electrodes 135 and 140 are dry
electrodes. Control unit 130 can release the conductive fluid from the receptacles to
enhance an electrical connection between sensing electrode 135 or therapy electrode
140 and a subject wearing wearable therapeutic device 100 to, for example, sense
electrocardiograph information about the subject or to apply treatment to the subject.
The receptacles can be replaced after their conductive fluid has been released, or upon
their expiration. When a shock is applied, therapy electrodes 140, the subject's body,
and external defibrillator 115 form at least part of a current path. One embodiment
includes at least one sensing electrode 135, one therapy electrode 140 disposed in
front of the subject, e.g., proximate to the subject's chest, and two therapy electrodes
140 disposed in back of the subject, e.g. proximate to the subject's back.
Garment 105 can hold electrodes 135 and 140 in position, for example against
the subject's skin around the subject's torso. Clothes or other material may be present
between garment 105 and the subject's skin. When positioned against the subject,
sensing electrodes 135 can sense electrocardiogram signals used be control unit 130 to
monitor the subject's cardiac activity. When control unit 130 identifies an arrhythmia
or other cardiac event, therapy electrodes 140, when positioned with a conductive
surface facing the subject can deliver defibrillating energy to the subject to convert
the arrhythmia to a normal sinus rhythm.
In one embodiment, sensing electrodes 135 and therapy electrodes 140 are
securely positioned facing the subject's body in order for sensing electrodes 135 to
sense cardiac, respiratory, or other information about the subject; and for therapy
electrodes 140 to apply treatment to the subject. For example, sensing electrode 135
can include electrocardiogram electrodes that directly or indirectly (e.g., via clothes, a
conductive protective barrier, or a conductive fluid) contact the subject's skin to sense
an electrocardiogram signal with minimal artifacts. Further, a conductive surface of
therapy electrode 140 can directly or indirectly contact the subject's skin to reduce
impedance between therapy electrode 140 and the subject's skin and to efficiently
deliver defibrillating energy to the subject, without causing burns, blisters,
inflammation, or other damage to the subject's skin. In one embodiment, conductive
fluid is released from replaceable receptacles that are disposed in wearable therapeutic
device 100 to contact the subject's skin and surfaces of sensing electrode 135 or
therapy electrode 140 to reduce impedance and improve the quality of sensed
electrocardiogram signals.
In one embodiment wearable therapeutic device 100 includes at least one
conductive thread 150. Conductive thread 150 can include a metallic or other
conductive material, such as a conductive wire that is configured in a stitched (e.g.,
zig-zag) pattern. Conductive thread 150 can stretch or expand together with garment
105. Conductive thread 150 may be at least partially shielded, jacketed, or insulated,
and may include contact surfaces that are broader than the rest of conductive thread
150 and configured to contact conductive surfaces of sensing electrode 135 or therapy
electrode 140. Conductive thread 150 can connect to a power supply of wearable
therapeutic device 100 directly or via intervening elements such as conductive
element 155 or wires. The power supply can also be associated with external
defibrillator 115, control unit 130, alarm module 120, or monitor 125.
Control unit 130 can detect open or closed circuits that include conductive
thread 150 and at least one of sensing electrode 135 and therapy electrode 140 to
determine that electrode 135 or 140 is improperly positioned, e.g., facing away from
the subject, or properly positioned, e.g., facing toward the subject, (or the area the
subject occupies when the subject is wearing wearable therapeutic device 100). For
example, conductive thread 150 can be located in a lateral side of pocket 160 distal
from the subject. When a conductive surface of electrodes 135 or 140 contacts the
conductive thread, that conductive surface is facing away from the subject, and in this
example is improperly positioned to sense cardiac information or to apply therapy.
Control unit 130 can detect this contact, for example by detecting current due to the
closed circuit formed by the contact, to determine that electrode 135 or 140 is
improperly positioned. In another example, conductive thread 150 can be located in a
lateral side of pocket 160 that is proximate to the subject. When a conductive surface
of electrodes 135 or 140 contacts the conductive thread, that conductive surface in this
example is facing toward the subject, and properly positioned to sense cardiac
information or to apply therapy. The formation of this circuit through which current
may flow can be identified by control unit 130 to determine that electrode 135 or 140
is properly positioned.
In other examples, when conductive thread 150 is proximate to the subject,
e.g., in a lateral side of pocket 160 closest to the subject, an open circuit can indicate
that electrodes 135 or 140 are absent or improperly positioned with their conductive
surfaces facing away from the subject. When conductive thread 150 is distal to the
subject, e.g., in a lateral side of pocket 160 furthest from the subject, an open circuit
can indicate that electrodes 135 or 140 are properly positioned with conductive
surfaces facing toward the subject, and away from conductive thread 150 in this
example.
In one embodiment, garment 105 or its components (e.g., belt 110 or strap
145) include at least one pocket 160 to house at least one electrode (e.g., sensing
electrode 135 or therapy electrode 140). At least one pocket 160 can also house
control unit 130, external defibrillator 115, alarm module 120, monitor 125, and
power supplies and other electronic equipment such as memory storage units. Pocket
160 can have the form of a pouch, sleeve, slit, or flap with an opening on at least one
side for entry or removal of sensing electrode 135 or therapy electrode 140. At least
one button, snap, or zipper, can secure openings of pocket 160 so that, for example,
therapy electrode 140 does not fall out of pocket 160 due to subject movement. In
one embodiment, the opening of pocket 160 is not secured by an additional element
(e.g., button, snap, hook and loop fastener, fastener, latch, or zipper) and is formed to
accommodate sensing electrode 135 or therapy electrode 140. For example, at least
part of pocket 160 can have elastic characteristics so that at least a portion expands to
accommodate entry of sensing electrode 135 or therapy electrode 140, and contracts
to secure any electrode housed in pocket 160.
In one embodiment, pocket 160 has first and second lateral sides, seams
around three edges, and a fourth edge open to accommodate entry and removal of
sensing electrode 135 or therapy electrode 140 into pocket 160. The seams need not
be continuous, and need not be stitched. For example, a series of buttons, hook and
loop fasteners, zippers or snaps can attach the first and second lateral sides of pocket
160 to each other. The seams can have openings to accommodate wires or other
electrical components connected to sensing electrode 135 or therapy electrode 140
and, for example, control unit 130.
In one embodiment, at least one of the first and second lateral sides of pocket
160 is formed at least in part from a conductive mesh material. For example, the
mesh material can be a conductive (e.g., metallic) fabric in a fine grid or mesh pattern
included in the lateral side of pocket 160 that is facing the subject. The mesh material
can facilitate an electrical connection between sensing electrode 135 or therapy
electrode 140 and the subject's skin. In one embodiment, conductive thread 150 is
included in at least one lateral side of pocket 160. For example, a first lateral side of
pocket 160 that faces away from the subject (when wearing wearable therapeutic
device 100) can include conductive thread 150, and a second lateral side that faces
toward the subject can include the conductive mesh material. Conductive thread 150
can be included in both lateral sides of pocket 160. In one embodiment, control unit
130 detects electrical connections, (e.g., current) between conductive thread 150 and
sensing electrode 135 or therapy electrode 140 to determine proper or improper
positioning of electrodes 135, 140.
In one embodiment, prior to sensing cardiac information or applying therapy, a
conductive fluid is released from capsules proximate to the mesh fabric. The capsules
may be located in or proximate to pocket 160. The conductive fluid can cover at least
part of the mesh fabric and the subject's skin, and a conductive surface of sensing
electrode 135 or therapy electrode 140 to reduce impedance. This can reduce artifacts
in the signal from sensing electrode 135 and causes a more efficient and comfortable
application of therapy from therapy electrode 140.
In one embodiment, control unit 130 includes at least one processor as
described in commonly owned U.S. Patent Application Serial No. 12/833,096, titled
"System and Method for Conserving Power in a Medical Device," filed on July 9,
2010, which is incorporated by reference herein in its entirety. The referenced
application generally describes a processing architecture configured to conserve
energy. Control unit 130 can monitor a subject's condition and control wearable
therapeutic device 100 operations. For example, sensing electrode 135 can sense
electrical activity of the subject's heart signals. These signals can be displayed as an
electrocardiograph on monitor 125. When an arrhythmic event or other form of
cardiac distress is detected, alarm module 120 can provide a warning that the subject
wearing wearable therapeutic device 100 is in danger of, or is experiencing, for
example, cardiac arrest. This warning may be audio, visual, haptic (e.g., vibrating
alarm module 120) or combinations thereof. This and other information can be stored
in memory units associated with control unit 130 for analysis by a doctor, rescuer, the
subject, or a health care provider.
In one embodiment, alarm module 120 provides an alarm that indicates that
the subject will receive an electric shock from external defibrillator 115 and at least
one therapy electrode 140 when the subject is wearing wearable therapeutic device
100, with therapy electrode 140 disposed proximate to the subject's body. Treatment
in the form of an electric shock can be applied to the subject wearing wearable
therapeutic device 100 unless the subject takes some action to prevent external
defibrillator 115 from applying the shock. For example, alarm module 120 or monitor
125 may include an interface having at least one button or touch screen. In this
example, the subject can depress a button. This indicates that the subject is conscious.
In this example, the shock will not be applied while the subject depresses the button
for a sufficient amount of time, or until control unit 130 determines that the electrical
heart activity of the subject, detected for example by sensing electrode 135, has
returned to normal. Continuing with this example, if the subject looses
consciousness, the subject may release the buttons and external defibrillator 115 can
apply a shock via at least one therapy electrode 140.
Alarm module 120 can be part of monitor 125 or a separate element of
wearable therapeutic device 100. In one embodiment, alarm module 120 alerts and
instructs the subject to take corrective action to position or reposition sensing
electrode 135 or therapy electrode 140. In one embodiment, alarm module 120
provides a notification that sensing electrode 135 or therapy electrode 140 is
improperly positioned. For example, an improperly positioned conductive surface of
electrode 135 or 140 can be facing away from the subject, (e.g., not facing towards or
not contacting the subject's skin so that information cannot be sensed or therapy
cannot be applied) and can contact conductive thread 150. This improper positioning
may be due to the subject, manufacturer, or health care provider accidentally inserting
electrode 135 or 140 backwards, with its conductive surface facing away from the
subject; or due to movement of the subject while wearing wearable therapeutic device
100. The contact between conductive thread 150 and a conductive surface of sensing
electrode 135 or therapy electrode 140 can complete or close an electrical circuit,
causing current to follow a path that includes conductive thread 150 and a conductive
surface of electrode 135 or 140. Control unit 130 can identify the closed circuit,
which indicates an improperly positioned electrode 135 or 140, and instruct alarm
module 120 to notify the subject of the improper positioning.
Alarm module 120 can also provide a notification that sensing electrode 135
or therapy electrode 140 is properly positioned. For example, conductive thread 150
can be located between the subject and a conductive surface of sensing electrode 135
or therapy electrode 140. In this example, contact between conductive thread 150 and
electrode 135 or 140 indicates that electrodes 135 or 140 are properly positioned, with
their conductive surfaces facing toward the subject. Control unit 130 can detect this
contact and instruct alarm module 120 to notify the subject of the proper electrode
135, 140 positioning.
Alarm module 120 can instruct the subject to tighten belt 110 to position or
reposition sensing electrode 135 or therapy electrode 140. This can reduce, for
example, signal interference at sensing electrode 135 by positioning this electrode
proximate to the subject's skin, or proximate to a desired portion of the subject's body
where a stronger electrocardiogram signal can be sensed. This can also reduce
impedance between therapy electrode 140 and the subject, or between a plurality of
therapy electrodes 140, allowing for more efficient and effective application of
therapy to the subject.
Sensing electrode 135 and therapy electrode 140 can be temporary or
permanent components of wearable therapeutic device 100. Electrodes 135 and 140
can be housed anywhere in garment 105. For example, at least one sensing electrode
135 can be integral to garment 105 and disposed in pocket 160 proximate to the
subject's chest or abdomen when the subject is wearing wearable therapeutic device
100. At least one therapy electrode 140 can be integral to garment 105 and disposed
in pocket 160 proximate to the subject's back when the subject is wearing wearable
therapeutic device 100. Sensing electrode 135 and therapy electrode 140 may include
conductive surfaces such as a metal plate, foil, mesh, wires, thread, or conductive
material in a generally circular, ovoid, or quadrilateral shape.
In one embodiment, sensing electrode 135 and therapy electrode 140 include
conductive material woven, sewn, or embroidered into wearable treatment device 100.
The conductive material can provide connections between any of electrodes 135 and
140, conductive thread 150, conductive element 155, and a battery powered external
defibrillator 5. In one embodiment, sensing electrode 135 senses the subject's
electrocardiogram signals and provides the sensed information to control unit 130 or
external defibrillator 115.
The conductive material that may form at least part of sensing electrode 135
and therapy electrode 140 can have various patterns to achieve proper
electrocardiogram sensing and to administer therapy. In one embodiment, sensing
electrode 135 or therapy electrode 140 includes only conductive stitching. Sensing
electrode 135 or therapy electrode 140 may also include conductive stitching that
holds a metal foil or other conductive component in place in garment 105, so that
sensing electrode 135 or therapy electrode 140 includes both conductive thread and a
conductive foil.
The conductive material can be sewn into garment 105 (e.g., belt 110) in a
zigzag pattern that can stretch as part of garment 105. This stretchable conductive
stitching connects sensing electrode 135 and therapy electrode 140 with control unit
130 or other garment 105 components (e.g., external defibrillator 115) in the absence
of additional wires. In one embodiment, the conductive material (e.g., conductive
wiring) can face toward or away from the subject's skin.
In one embodiment, garment 105 includes breathable fabric, or a material that
wicks heat away from the subject's body. This can reduce heat buildup between the
subject's skin and sensing electrode 135 or therapy electrode 140. Using conductive
stitching for electrodes 135 or 140 reduces heat buildup in one embodiment when
electrodes 135 or 140 are formed from stitched conductive material in the absence of
any further metallic or conductive foil. In one embodiment, sensing electrode 135 or
therapy electrode 140 are made of perforated conductive materials that allow air flow
proximate to the subject's skin. This air flow can dry sweat or other fluid from the
skin to avoid rashes and other skin problems as a result of heat buildup and irritation.
Garment 105 can be adjusted to snugly fit the subject. For example, portions
of garment 105 that include sensing electrode 135 and therapy electrode 140 can be
substantially flush against the subject, e.g., electrodes 135 and 140 remain
substantially in a fixed position against the subject when the subject is moving about
as part of a daily routine, or undertaking moderate physical activity. Clothing may be
present between garment 105 and the subject. Alarm module 120 can alert the subject
when wearable therapeutic device 100 is not sufficiently tight and snug about the
subject. For example, alarm module 120 can notify the subject when the portion of
garment 105 (e.g., pocket 160) that includes sensing electrode 135 or therapy
electrode 140 is not flush with or fairly tightly pressed against the patient in a
substantially fixed position.
Garment 105 or its components such as belt 110 or strap 145 can expand or
stretch with time or repeated use, which can loosen the fit and positioning of sensing
electrode 135 and therapy electrode 140 proximate to the subject. Further, the
subject's respiration will typically result in periodic expansion of garment 105.
Control unit 130 can detect this expansion and where appropriate, instruct the subject
to reposition sensing electrode 135 or therapy electrode 140, for example by
tightening garment 105.
Wearable therapeutic device 100 can include at least one conductive element
155, located for example in garment 105, belt 110, or strap 145. In one embodiment,
conductive element 155 connects conductive thread 150 with control unit 130. For
example, conductive element 155 can be part of the circuit formed when conductive
thread 150 and a conductive surface of sensing electrode 135 or therapy electrode 140
make electrical contact with one another. In one embodiment, a connector such as a
snap or male-female connector makes the connection between conductive element
155 and conductive thread 150.
Figure 2 is a schematic diagram depicting wearable therapeutic device 100 in
accordance with an embodiment. In the example of Figure 2, garment 105 includes
two pockets 160 proximate to the back of subject 200. Each of these pockets 160
includes one therapy electrode 140. While not directly illustrated in Figure 2, pockets
160 can include conductive thread 150, for example sewn into the inner lateral side of
pocket 160 nearest to subject 200, or the outer lateral side of pocket 160, farthest from
subject 200. Sensing electrode 135 is also disposed in pocket 160 proximate to the
chest of subject 200, in the general vicinity of the heart. Conductive element 155
connects control unit 130 with therapy electrodes 140. Wearable therapeutic device
100 can include more than one conductive element 155. For example, the same or a
second conductive element 155 can connect control unit 130 with at least one sensing
electrode 135. Wearable therapeutic device 100 can include other elements not
illustrated in Figure 2, such as power supplies, additional electrodes, and additional
straps across the chest of subject 200 that can include conductive element 155. In one
embodiment, at least one therapy electrode 140 is located in a pocket 160 in front of
subject 200, proximate to the chest.
In one embodiment, control unit 130 determines the orientation of sensing
electrodes 135 or therapy electrodes 140 to determine if they are properly positioned
with a conductive surface of electrodes 135, 140 facing toward subject 200 or
improperly positioned with a conductive surface of electrodes 135, 140 facing away
from subject 200. Control unit 130 can instruct alarm module 120 to provide a
notification to subject 200. The notification can instruct subject 200 to position or
reposition sensing electrode 135 or therapy electrode 140. The notification can also
indicate that an arrhythmic cardiac event has been detected, based on information
from sensing electrode 135, and provide a warning that therapy has been or will be
applied within a time period of, for example, a few seconds.
Figure 3 depicts a portion of garment 105 where pocket 160 includes
conductive thread 150 in accordance with an embodiment. With reference to Figure
3, conductive thread 150 can be sewn into the fabric of lateral side 305 of pocket 160.
Lateral side 305 can be the interior lateral side of pocket 160 that faces inward toward
the subject when the subject is wearing wearable therapeutic device 100, or can be the
exterior lateral side of pocket 160 that faces outward away from the subject when the
subject is wearing wearable therapeutic device 100. In one embodiment, the second
lateral side of pocket 160, not visible in Figure 3, includes a conductive mesh that
lowers impedance of the electrical connection between, for example, therapy
electrode 140 and the subject.
In one embodiment, opening 310 of pocket 160 receives sensing electrode 135
or therapy electrode 140. One or more flaps, buttons, snaps, fasteners, latches, hook
and loop fasteners, or zippers may close opening 310 when electrode 135 or 140 is
disposed in pocket 160. Electrodes 135 or 140 can be removed from pocket 160 to be
replaced, recharged, repaired, or repositioned. One or more connectors 315 such as
conductive snaps 320 can couple conductive thread 150 with conductive element 155.
Control unit 130 can receive as input information from conductive element 155 to
determine that conductive thread 150 is or is not in contact with a conductive surface
of electrode 135 or 140.
At least one therapy electrode 140 can be disposed in pocket 160, as depicted
in Figure 3. Sensing electrodes 135 may also be disposed in pockets 160. In one
embodiment, conductive surface 325 of therapy electrode 140 contacts conductive
thread 150 sewn into lateral side 305 of pocket 160. Control unit 130 can determine
that this contact has been made, for example by sensing current in conductive element
155, to identify the direction in which conductive surface 325 is facing, e.g., inward
toward the subject or outward away from the subject. Control unit 130 can then
instruct therapy electrode 140 and defibrillator 115 to apply treatment (e.g., when
therapy electrode 140 is properly positioned) or to withhold treatment (e.g., when
therapy electrode 140 is improperly positioned). Control unit 130 with alarm module
120 or monitor 125 can also can notify the subject of proper of improper positioning,
or instruct the subject to reposition therapy electrode 140 or garment 105.
Figure 4 depicts a portion of garment 105 where pocket 160 includes
conductive thread 150 in accordance with an embodiment. Conductive thread 150
can form various patterns in lateral side wall 305 of pocket 160. For example,
conductive thread 150 can be woven into the fabric of pocket 160 to form a series of
lines, each line substantially parallel to an edge of lateral side 305, with a conductive
patch 405 disposed in each of the four corners of lateral side 305. An additional
conductive patch 405 may be located substantially in the center of lateral side 305,
with conductive thread 150 connecting the central conductive patch 405 with the rest
of the pattern. Conductive patches 405 can include conductive thread 150 around
their edges, with central portion 410 being made of the same material as the rest of
lateral side wall 305, or central portion 410 can include conductive material, such as a
mesh, connected to conductive thread 150. One or more conductive elements 155 can
connect with conductive thread 150 at one or at a plurality of different points of
conductive thread 150, such as at one or more conductive patches 405, or at the corner
areas of lateral side wall 305. In one embodiment, a plurality of conductive elements
155 connects with a plurality of conductive threads 150 at lateral side 305.
Figure 5 depicts a portion of garment 105 where pocket 160 includes
conductive thread 150 in accordance with an embodiment. Conductive thread 150
can be woven around the edges of lateral side 305 with a plurality of substantially
parallel lines of conductive thread 150 running diagonally across lateral side 305. The
substantially parallel lines may or may not be evenly spaced. Other configurations are
possible. For example, conductive thread 150 may form serpentine, circular, oval,
quadrilateral, coiled, or triangular shapes on lateral side 305. In one embodiment,
conductive thread 150 is woven into lateral side 305 sufficiently spaced so that
conductive surface 325 contacts conductive thread 150 when sensing electrode 135 or
therapy electrode 140 is disposed in pocket 160 with conductive surface 325 facing
lateral side 305. Conductive elements 155 can connect with conductive thread 150 at
multiple points of conductive thread 150.
Figure 6 depicts a cross sectional view of garment 105 with therapy electrode
140 disposed in pocket 160. Conductive surface 325 is facing toward conductive
mesh 605 and subject 200, away from conductive thread 150, and in this example is
properly positioned to apply treatment to subject 200 because conductive surface 325
is in contact with subject 200 via conductive mesh 605. Intervening elements such as
conductive fluid or clothes can be present. Conductive thread 150 is woven into
lateral side 305 of pocket 160 and not in electrical contact with conductive surface
325. In one embodiment, control unit 130 can determine that therapy electrode 140 is
properly positioned in pocket 160 based on the absence of an electrical connection
between conductive surface 325 and conductive thread 150. In one embodiment,
sensing electrodes are disposed in pocket 160.
In one embodiment, sensing electrode 135 or therapy electrode 140 includes a
plurality of conductive surfaces 325. For example, rather than a single continuous
conductive surface 325, therapy electrode 140 can have two separate conductive
surfaces 325 with an insulating or non-conductive gap between them. In this
example, a closed circuit forms when conductive thread 150 bridges the gap and
contacts each of the two (or other plurality) of conductive surfaces 325. Control unit
130 can determine that therapy electrode 140 is improperly positioned in pocket 160
based on the electrical connection between both conductive surfaces 325 and
conductive thread 150, or that therapy electrode 140 is properly positioned in pocket
160 based on an absence of an electrical connection.
Figure 7 depicts a cross sectional view of garment 105 with therapy electrode
140 disposed in pocket 160. Conductive surface 325 is facing toward conductive
thread 150, away from conductive mesh 605 and subject 200, and in this example is
improperly positioned to apply treatment to the subject because conductive surface
325 is not directly or indirectly in contact with subject 200. Conductive thread 150 is
woven into lateral side 305 of pocket 160 and is in electrical contact with conductive
surface 325. In one embodiment, control unit 130 can detect this electrical connection
and based on this connection determine that therapy electrode 140 is improperly
positioned in pocket 160. It should be appreciated that the therapy electrode 140
could have a plurality of conductive surfaces 325 separated by an insulating or nonconductive
gap, with the presence of an electrical connection between the conductive
surfaces 325 (due to the presence of the conductive thread) being indicative of
improper positioning. In one embodiment, sensing electrodes may also be disposed in
a pocket similar to that of pocket 160.
In one embodiment, surfaces of pocket 160 can include a pressure sensor such
as a spring loaded sensor or piezoelectric sensor to detect contact with conductive
thread 150, as an alternative or complement to conductive surface 325. Sensing
electrodes 135 and therapy electrodes 140 can also include pressure sensors to detect
contact with surfaces of pocket 160. These pressure sensors can include conductive
elements to detect electrical connections with garment 105 components such as
conductive surface 325 or conductive thread 150. These pressure sensors can also
determine that garment 105 is properly fitted on the subject with the appropriate
amount of tension to hold garment components such as therapy electrodes 140 in
position suitable to deliver treatment to the subject.
Figure 8 is a flowchart depicting a method 800 of facilitating care of a subject.
In one embodiment, method 800 includes an act of providing a wearable therapeutic
device (ACT 805). In one embodiment, providing the wearable therapeutic device
(ACT 805) includes providing a device that includes at least one electrode, such as a
therapy electrode or sensing electrode, and at least one length of conductive thread.
The electrode may be housed in a garment of the wearable therapeutic device, and
providing the wearable therapeutic device (ACT 805) may include providing a device
with the conductive thread included in at least part of the garment, such as a lateral
side of a pocket where the electrode is included.
Providing the wearable therapeutic device (ACT 805) may also include
providing a device having a control unit configured to identify electrical connections
between conductive surfaces of electrodes and conductive thread, to determine, based
on the identified connections or lack thereof, positioning of an electrode, and to notify
the subject of proper or improper electrode positioning. Providing the wearable
therapeutic device (ACT 805) may also include providing a device with an alarm
module coupled with a control unit to notify the subject of events, conditions, or
information about the subject's condition or about the condition of the wearable
therapeutic device, including positioning of its components.
Method 800 can include an act of identifying an electrical connection (ACT
810). In one embodiment, this includes identifying an electrical connection between a
conductive surface of the therapy electrode and the conductive thread. For example,
contact between the conductive surface and the conductive thread may form a circuit,
and a control unit can sense current that follows a path between the conductive
surface and the conductive thread to identify (ACT 810) an electrical connection
between these components. Other elements can be included in the circuit, such as a
conductive element, e.g., a wire that connects the conductive thread with, for
example, a power supply or control unit.
Method 800 can include an act of determining electrode positioning (ACT
815). In one embodiment, determining electrode positioning (ACT 815) is based on
the identified electrical connection (ACT 810). For example, when the conductive
thread is woven into a lateral side pocket distal from a subject, or distal from the area
that a subject occupies when the subject is wearing the device, electrode positioning
can be determined (ACT 815) to be improperly facing away from the subject when an
electrical connection is identified (ACT 810).
In one embodiment, electrode positioning can be determined (ACT 815) to be
proper when an electrical connection is not identified (ACT 810). For example, an
open circuit can be detected, the open circuit including at least portions of the
conductive surface of the electrode and the conductive thread. When the conductive
thread is located between the subject and the conductive surface of the electrode, the
electrode can be determined (ACT 815) to be properly positioned when there is
contact between the conductive surface of the electrode and the conductive thread.
Method 800 may include an act of providing a notification (ACT 820). In one
embodiment, an alarm module provides notification (ACT 820) that an electrode is
properly or improperly positioned. The notification may be provided (ACT 820)
audibly, visually, or haptically by an alarm module included in the wearable
therapeutic device. The notification can be provided (ACT 820) to the subject
wearing the device or to a health care provider remote from the subject via a network
connection. In one embodiment, providing the notification (ACT 820) includes
providing instructions to adjust positioning of an electrode. For example, notification
can be provided (ACT 820) that an electrode is improperly positioned in a pocket of
the device, and the notification can include instructions to position the electrode with
its conductive surface facing inward, toward the subject. In one embodiment,
providing a notification (ACT 820) confirms proper placement of an electrode.
Notification can also be provided indicating that a cardiac event or other information
has been sensed by a sensing electrode, that therapy will be applied by a treatment
electrode, or that therapy has been applied by a treatment electrode. In one
embodiment, providing a notification (ACT 820) alerts bystanders or health care
providers to stay away from and not touch the subject due to past application of
therapy (e.g., a defibrillation shock) or imminent future application of therapy.
In one embodiment, method 800 includes an act of providing instructions
(ACT 825). For example, providing instructions (ACT 825) can include providing
instructions to operate the wearable therapeutic device, or providing instructions on
how to wear the wearable therapeutic device. In one embodiment, the instructions
include instructions to the subject regarding positioning of wearable therapeutic
device components, such as sensing or therapy electrodes. For example, due to an
identified (ACT 810) electrical connection between an electrode and conductive
thread of the garment, instructions can be provided (ACT 825) to the subject to
position an electrode proximate to an area of the subject's body, such as the center of
the back, or proximate to the chest and heart of the subject, so that the electrodes are
positioned to provide therapy to the subject or to sense cardiac or respiratory function
of the subject.
Having now described some illustrative embodiments, it is apparent that the
foregoing is illustrative and not limiting, having been presented by way of example.
In particular, although many of the examples presented herein involve specific
combinations of method acts or system elements, it is understood that those acts and
those elements may be combined in other ways to accomplish the same objectives.
Acts, elements and features discussed only in connection with one embodiment are
not intended to be excluded from a similar role in other embodiments.
Note that in Figures 1 through 8, the enumerated items are shown as individual
elements. In actual implementations of the systems and methods described herein,
however, they may be inseparable components of other electronic devices such as a
digital computer. Thus, actions described above may be implemented at least in part
in software that may be embodied in an article of manufacture that includes a program
storage medium. In one embodiment, the program storage medium is non-transitory.
The program storage medium includes data signals embodied in one or more of a
carrier wave, a computer disk (magnetic, or optical (e.g., CD or DVD, or both)), non
volatile memory, tape, a system memory, and a computer hard drive.
From the foregoing, it is appreciated that embodiments of the wearable
therapeutic device described herein afford an effective way to verify proper electrode
positioning. The wearable therapeutic device according to various embodiments is
able to determine electrode positioning based on electrical connections between the
electrode and conductive thread woven into the garment so that information may be
sensed accurately and so that therapy may be applied when appropriate. This
increases efficiency and effectiveness of the wearable therapeutic device.
Any references to front and back, left and right, top and bottom, inner and
outer, toward and away, or upper and lower and the like are intended for convenience
of description, not to limit the present systems and methods or their components to
any one positional or spatial orientation.
Any references to embodiments or elements or acts of the systems and
methods herein referred to in the singular may also embrace embodiments including a
plurality of these elements, and any references in plural to any embodiment or
element or act herein may also embrace embodiments including only a single element.
References in the singular or plural form are not intended to limit the presently
disclosed systems or methods, their components, acts, or elements to single or plural
configurations. References to any act or element being based on any information, act
or element may include embodiments where the act or element is based at least in part
on any information, act, or element.
Any embodiment disclosed herein may be combined with any other
embodiment, and references to "an embodiment," "some embodiments," "an alternate
embodiment," "various embodiments," "one embodiment" or the like are not
necessarily mutually exclusive and are intended to indicate that a particular feature,
structure, or characteristic described in connection with the embodiment may be
included in at least one embodiment. Such terms as used herein are not necessarily all
referring to the same embodiment. Any embodiment may be combined with any
other embodiment in any manner consistent with the aspects and embodiments
disclosed herein.
References to "or" may be construed as inclusive so that any terms described
using "or" may indicate any of a single, more than one, and all of the described terms.
Intervening embodiments, acts, or elements are not essential unless recited as such.
Where technical features in the drawings, detailed description or any claim are
followed by reference signs, the reference signs have been included for the sole
purpose of increasing the intelligibility of the drawings, detailed description, and
claims. Accordingly, neither the reference signs nor their absence have any limiting
effect on the scope of any claim elements.
One skilled in the art will realize the systems and methods described herein
may be embodied in other specific forms without departing from the characteristics
thereof. For example, references to electrodes facing toward or away from the subject
include references to where the subject would be positioned when wearing the
wearable therapeutic device. Electrode positioning can be determined in the absence
of the subject wearing the device. Further, conductive thread, conductive elements,
electrodes, and other components can be at least partially insulated, jacketed, or
sleeved. Electrode positioning can be determined to be proper or improper based on
detection of electrical connections or the absence of electrical connections. For
example, either an electrical connection indicating an outward facing electrode, or the
absence of an electrical connection indicating an inward facing electrode, can indicate
an improperly positioned electrode. In some embodiments, an electrical connection
indicating an inward facing electrode, or the absence of an electrical connection
indicating an outward facing electrode, can indicate a properly positioned electrode.
The foregoing embodiments are illustrative rather than limiting. Scope of the systems
and methods described herein is thus indicated by the appended claims, rather than the
foregoing description, and changes that come within the meaning and range of
equivalency of the claims are embraced therein.
CLAIMS
1. A wearable therapeutic device, comprising:
a garment configured to include an electrode;
a conductive thread included in at least part of the garment; and
a control unit coupled to the conductive thread and configured to identify an
electrical connection between a conductive surface of the electrode and the
conductive thread; and
an alarm module configured to indicate positioning information of the
electrode in the garment based on the electrical connection.
2. The wearable therapeutic device of claim 1, wherein the garment includes a pocket
configured to house the electrode, the pocket having a first lateral side and a second
lateral side; and
wherein the conductive thread is integrated into one of the first lateral side and
the second lateral side of the pocket.
3. The wearable therapeutic device of claim 1, wherein the alarm module indicates
improper positioning of the electrode, and wherein the garment includes a pocket
configured to house the electrode, the pocket having a first lateral side that includes a
conductive mesh and a second lateral side that includes the conductive thread.
4. The wearable therapeutic device of claim 3, further comprising:
a conductive element included in the garment;
wherein the control unit is further configured to detect a current path that
includes the conductive thread, the conductive surface of the electrode, and the
conductive element.
5. The wearable therapeutic device of claim 4, wherein the alarm module is
configured to notify at least one of a subject wearing the wearable therapeutic device
and a health care provider that the electrode is improperly positioned.
6. The wearable therapeutic device of claim 4, further comprising:
a monitor configured to display an indication that the electrode is improperly
positioned.
7. The wearable therapeutic device of claim 1, wherein the alarm module is
configured to notify at least one of a subject wearing the wearable therapeutic device
and a health care provider that the electrode is improperly positioned.
8. The wearable therapeutic device of claim 1, further comprising:
a monitor configured to display an indication that the electrode is improperly
positioned.
9 . The wearable therapeutic device of claim 1, wherein the garment includes a pocket
configured to house the electrode, the pocket having a first lateral side proximate to a
subject and a second lateral side distal to the subject, and wherein the conductive
thread is disposed in the second lateral side of the pocket.
10. The wearable therapeutic device of claim 1, further comprising:
a conductive element included in the garment; and
a connector configured to couple the conductive thread with the conductive
element.
11. The wearable therapeutic device of claim 1, wherein the garment includes a belt,
the wearable therapeutic device further comprising:
a conductive element included in the belt; and
a connector configured to couple the conductive thread with the conductive
element to form electrical connection between the conductive surface of the electrode
and the conductive element.
12. The wearable therapeutic device of claim 11, wherein the connector includes a
snap.
13. The wearable therapeutic device of claim 1, wherein the conductive thread forms
a stitched pattern in the garment.
14. The wearable therapeutic device of claim 1, wherein the conductive thread forms
a stitched pattern including at least two substantially parallel stitched lines.
15. The wearable therapeutic device of claim 1, wherein the conductive thread forms
a pattern including at least one of a quadrilateral shape, a polygonal shape, an oblong
shape, a circular shape, an oval shape, a round shape, and a triangular shape.
16. The wearable therapeutic device of claim 1, wherein the conductive thread forms
part of an electrical connection with the electrode.
17. The wearable therapeutic device of claim 1, wherein the conductive surface of the
electrode includes a first portion and a second portion separated by an insulating gap.
18. A method of facilitating care of a subject, comprising:
providing a wearable therapeutic device that includes an electrode and a
conductive thread;
identifying an electrical connection between a conductive surface of the
electrode and the conductive thread; and
providing a notification to indicate positioning information of the electrode
based on the electrical connection.
19. The method of claim 18, wherein the wearable therapeutic device includes a
garment, the method further comprising:
removably housing the electrode in a pocket of the garment and proximate to
the conductive thread.
20. The method of claim 18, further comprising:
determining that the electrode is positioned with a conductive surface of the
electrode facing away from a subject.
21. The method of claim 20, further comprising:
detecting a closed circuit that includes a conductive surface of the electrode
and the conductive thread; and
determining that the electrode is improperly positioned.
22. The method of claim 18, wherein the wearable therapeutic device includes a
garment having a conductive element, the method further comprising:
detecting a current path between the conductive thread, the conductive surface
of the electrode, and the conductive element.
23. The method of claim 22, further comprising:
electrically coupling the conductive thread with the conductive element.
24. The method of claim 22, further comprising:
coupling the conductive thread with the conductive element to form an
electrical connection between the conductive surface of the electrode and the
conductive element.
25. The method of claim 18, wherein the conductive surface of the electrode includes
a first portion and a second portion that are electrically separated by an insulating gap,
and wherein the act of identifying the electrical connection includes an act of:
detecting that the first portion and the second portion are electrically
connected; and
identifying the electrical connection between the first portion and the second
portion, and the gap that is formed by the conductive thread.