U.S. patent application number 14/703996 was filed with the patent office on 2015-08-20 for water resistant wearable medical device.
The applicant listed for this patent is ZOLL MEDICAL CORPORATION. Invention is credited to John G. Clark, Thomas E. Kaib, Shane S. Volpe.
Application Number | 20150231403 14/703996 |
Document ID | / |
Family ID | 46235381 |
Filed Date | 2015-08-20 |
United States Patent
Application |
20150231403 |
Kind Code |
A1 |
Kaib; Thomas E. ; et
al. |
August 20, 2015 |
WATER RESISTANT WEARABLE MEDICAL DEVICE
Abstract
An accessory kit for use with a wearable medical device, such as
a wearable defibrillator, that includes a control unit and a first
plurality of electrodes electrically coupled to the control unit.
The first plurality of electrodes includes a first plurality of ECG
sensing electrodes and a first plurality of therapy electrodes
configured to provide a defibrillating shock to a body of a
patient. The accessory kit includes a waterproof enclosure
configured to receive the control unit and protect the control unit
during operation in a wet environment and a second plurality of
electrodes that are electrically coupled to a connector configured
to removably and electrically couple to the control unit. The
second plurality of electrodes includes a second plurality of ECG
sensing electrodes and a second plurality of therapy electrodes
configured to provide a defibrillating shock to the body of the
patient.
Inventors: |
Kaib; Thomas E.; (Irwin,
PA) ; Volpe; Shane S.; (Saltsburg, PA) ;
Clark; John G.; (Pittsburgh, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ZOLL MEDICAL CORPORATION |
Chelmsford |
MA |
US |
|
|
Family ID: |
46235381 |
Appl. No.: |
14/703996 |
Filed: |
May 5, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13311427 |
Dec 5, 2011 |
|
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14703996 |
|
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61423874 |
Dec 16, 2010 |
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Current U.S.
Class: |
607/7 |
Current CPC
Class: |
A61N 1/0484 20130101;
A61N 1/0476 20130101; A61N 1/3925 20130101; A61N 1/3968 20130101;
A61N 1/3987 20130101; A61N 1/3993 20130101; A61N 1/046
20130101 |
International
Class: |
A61N 1/39 20060101
A61N001/39 |
Claims
1. A wearable medical device, comprising: a water-resistant harness
to be worn by a patient; a plurality of ECG sensing electrodes
disposed on the harness and configured to sense an ECG of the
patient; a plurality of therapy electrodes disposed on the harness
and configured to provide at least one defibrillating shock to the
body of the patient; and a control unit, electrically coupled to
the plurality of ECG sensing electrodes and the plurality of
therapy electrodes, configured to monitor the sensed ECG of the
patient, and responsive to detection of cardiac arrhythmia of the
patient, to provide at least one defibrillating pulse of energy to
at least one of the plurality of therapy electrodes, the control
unit being housed in a waterproof case formed from a waterproof
material that is sealed to prevent ingress of water during
operation of the wearable medical device in a wet environment.
2. The wearable medical device of claim 1, further comprising a
connection pod that electrically couples the plurality of ECG
sensing electrodes and the plurality of therapy electrodes to the
control unit, a body of the connection pod being formed from a
waterproof material, wherein any openings in the body of the
connection pod are sealed with a waterproof sealant.
3. The wearable medical device of claim 2, wherein the connection
pod includes electronic circuitry, and wherein the electronic
circuitry is potted in a waterproof potting compound.
4. The wearable medical device of claim 2, wherein the connection
pod is electrically connected to the plurality of ECG sensing
electrodes and the plurality of therapy electrodes by a removable
connector.
5. The wearable medical device of claim 4, wherein the removable
connector is waterproof.
6. The wearable medical device of claim 2, wherein the connection
pod is electrically connected to the control unit by a removable
and waterproof connector.
7. The wearable medical device of claim 2, wherein the connection
pod is permanently electrically coupled to the control unit in a
waterproof manner.
8. The wearable medical device of claim 2, further comprising a
user interface pod configured to wirelessly communicate with the
control unit, the user interface pod being housed in a waterproof
case that is sealed to prevent the ingress of water during
operation of the wearable medical device in a wet environment,
wherein the user interface pod includes a speaker that is sealed
with a water-resistant and sound permeable material.
9. The wearable medical device of claim 2, further comprising a
user interface pod, the user interface pod being housed in a
waterproof case that is sealed to prevent the ingress of water
during operation of the wearable medical device in a wet
environment.
10. The wearable medical device of claim 9, wherein the user
interface pod includes a speaker that is sealed with a
water-resistant and sound permeable material.
11. The wearable medical device of claim 9, wherein the user
interface pod is configured to wirelessly communicate with the
control unit.
12. The wearable medical device of claim 1, further comprising a
user interface pod, the user interface pod being housed in a
waterproof case that is sealed to prevent the ingress of water
during operation of the wearable medical device in a wet
environment.
13. The wearable medical device of claim 12, wherein the user
interface pod includes a speaker that is sealed with a
water-resistant and sound permeable material.
14. The wearable medical device of claim 12, wherein the user
interface pod is configured to wirelessly communicate with the
control unit.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C.
.sctn.121 as a division of U.S. application Ser. No. 13/311,427,
filed Dec. 5, 2011 and titled "WATER RESISTANT WEARABLE MEDICAL
DEVICE" which is incorporated herein by reference in its entirety.
U.S. application Ser. No. 13/311,427 claims priority under 35
U.S.C. .sctn.119(e) to U.S. Provisional Application Ser. No.
61/423,874 titled "WATER RESISTANT WEARABLE MEDICAL DEVICE," filed
Dec. 16, 2010, which is incorporated herein by reference in its
entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is directed to a water resistant
and/or waterproof wearable medical device, such as a
defibrillator.
[0004] 2. Discussion of Related Art
[0005] Cardiac arrest and other cardiac 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. These efforts are expensive and have a limited
success rate, and cardiac arrest, among other conditions, continues
to claim the lives of victims.
[0006] To protect against cardiac arrest and other cardiac health
ailments, some at-risk patients may use a wearable defibrillator,
such as the LifeVest.RTM. wearable cardioverter defibrillator
available from Zoll Medical Corporation of Chelmsford, Mass. To
remain protected, the patient wears the device nearly continuously
while going about their normal daily activities, while awake, and
while asleep.
SUMMARY OF THE INVENTION
[0007] In accordance with one embodiment, an accessory kit for use
with a wearable medical device is provided. The wearable medical
device includes a control unit and a first plurality of electrodes
electrically coupled to the control unit, the first plurality of
electrodes including a first plurality of ECG sensing electrodes
and a first plurality of therapy electrodes configured to provide a
defibrillating shock to a body of a patient. The accessory kit
comprises a waterproof enclosure configured to receive the control
unit and protect the control unit during operation in a wet
environment and a second plurality of electrodes. The second
plurality of electrodes includes a second plurality of ECG sensing
electrodes and a second plurality of therapy electrodes configured
to provide a defibrillating shock to the body of the patient, the
second plurality of electrodes being electrically coupled to a
connector that is configured to removably and electrically couple
to the control unit of the wearable medial device.
[0008] In accordance with one aspect of this embodiment, the
connector is a first connector, and the wearable medical device
includes a connection pod that is electrically connected to the
control unit, the connection pod being electrically connected to a
second connector that is configured to removably and electrically
connect to the first connector. In accordance with a further aspect
of this embodiment, the waterproof enclosure is further configured
to receive the connection pod and protect the connection pod and
the control unit during operation in the wet environment. In
accordance with yet a further aspect of this embodiment, the
connection pod is electrically connected to the second connector by
a cable, and the waterproof enclosure includes an aperture
configured to form a waterproof seal about the cable.
[0009] In accordance with another embodiment, the second plurality
of electrodes includes a pair of combined ECG/therapy electrodes,
each combined ECG/therapy electrode of the pair of combined
ECG/therapy electrodes including at least one ECG sensing electrode
and a therapy electrode mounted to a common backing. In accordance
with an aspect of this embodiment, each combined ECG/therapy
electrode of the pair of combined ECG/therapy electrodes includes
two ECG sensing electrodes and the therapy electrode mounted to the
common backing.
[0010] In accordance with another embodiment, the second plurality
of electrodes are electrically coupled to the connector via a
waterproof connection pod. In accordance with one aspect of this
embodiment, the waterproof connection pod includes electronic
circuitry that is potted with a waterproof potting compound, and
any openings in the waterproof connection pod are sealed with an
elastomeric sealant. In accordance with another aspect of this
embodiment, the waterproof connection pod is electrically connected
to the connector by a cable, and the waterproof enclosure includes
an aperture configured to form a waterproof seal about the cable.
In accordance with a further aspect of this embodiment, the second
plurality of electrodes includes a pair of combined ECG/therapy
electrodes, each combined ECG/therapy electrode of the pair of
combined ECG/therapy electrodes including at least one ECG sensing
electrode and a therapy electrode mounted to a common backing. In
accordance with yet a further aspect of this embodiment, each
combined ECG/therapy electrode of the pair of combined ECG/therapy
electrodes includes two ECG sensing electrodes and the therapy
electrode mounted to the common backing.
[0011] In accordance with a variety of different embodiments, each
respective electrode of the second plurality of electrodes includes
an adhesive to attach the respective electrode to the body of the
patient.
[0012] In accordance with another embodiment, the first plurality
of electrodes are electrically coupled to a first connection port
of the control unit via a first connection pod, and the second
plurality of electrodes are electrically coupled to the connector
via a waterproof connection pod, wherein the connector is
configured to removably and electrically couple to a second
connection port of the control unit that is distinct from the first
connection port. In accordance with an aspect of this embodiment,
the waterproof connection pod includes electronic circuitry that is
potted with a waterproof potting compound, and any openings in the
waterproof connection pod are sealed with an elastomeric sealant.
In accordance with a further aspect of this embodiment, the second
plurality of electrodes includes a pair of combined ECG/therapy
electrodes, each combined ECG/therapy electrode of the pair of
combined ECG/therapy electrodes including at least one ECG sensing
electrode and a therapy electrode mounted to a common backing. In
accordance with yet a further aspect of this embodiment, each
combined ECG/therapy electrode of the pair of combined ECG/therapy
electrodes includes two ECG sensing electrodes and the therapy
electrode mounted to the common backing, wherein at least one of
the pair of combined ECG/therapy electrodes further includes a
patient responsiveness button by which the patient can indicate to
the control unit that they are conscious.
[0013] In accordance with a further aspect of each of the
above-described embodiments, the wearable medical device includes a
user interface pod electrically coupled to the control unit, and
the accessory kit further comprises a second a waterproof enclosure
configured to receive the user interface pod and protect the user
interface pod during operation in a wet environment.
[0014] In accordance with another embodiment of the present
invention, a wearable medical device is provided. The wearable
medical device comprises a water-resistant harness to be worn by a
patient, a plurality of ECG sensing electrodes disposed on the
harness and configured to sense an ECG of the patient, a plurality
of therapy electrodes disposed on the harness and configured to
provide at least one defibrillating shock to the body of the
patient, and a control unit, electrically coupled to the plurality
of ECG sensing electrodes and the plurality of therapy electrodes,
configured to monitor the sensed ECG of the patient, and responsive
to detection of cardiac arrhythmia of the patient, to provide at
least one defibrillating pulse of energy to at least one of the
plurality of therapy electrodes. The control unit is housed in a
waterproof case formed from a waterproof material that is sealed to
prevent ingress of water during operation of the wearable medical
device in a wet environment.
[0015] In accordance with one aspect of this embodiment, the
wearable medical device further comprises a connection pod that
electrically couples the plurality of ECG sensing electrodes and
the plurality of therapy electrodes to the control unit, wherein a
body of the connection pod is formed from a waterproof material
wherein any openings in the body of the connection pod are sealed
with a waterproof sealant. In accordance with an aspect of this
embodiment, the connection pod includes electronic circuitry, and
the electronic circuitry is potted in a waterproof potting
compound. In accordance with another aspect of this embodiment, the
connection pod is electrically connected to the plurality of ECG
sensing electrodes and the plurality of therapy electrodes by a
removable connector. In accordance with this embodiment, the
removable connector is waterproof. In accordance with another
embodiment, the connection pod is electrically connected to the
control unit by a removable and waterproof connector. In accordance
with another embodiment, the connection pod is permanently
electrically coupled to the control unit in a waterproof
manner.
[0016] In accordance with a further aspect of the present
invention, the wearable medical device can further comprise a user
interface pod configured to wirelessly communicate with the control
unit, the user interface pod being housed in a waterproof case that
is sealed to prevent the ingress of water during operation of the
wearable medical device in a wet environment. In accordance with
this embodiment, the user interface pod includes a speaker that is
sealed with a water-resistant and sound permeable material.
[0017] In accordance with another embodiment of the present
invention, an accessory kit for use with a wearable medical device
is provided. The wearable medical device includes a control unit
and a first plurality of electrodes electrically coupled to the
control unit, the first plurality of electrodes including a first
plurality of ECG sensing electrodes and a first plurality of
therapy electrodes configured to provide a defibrillating shock to
a body of a patient. The accessory kit comprises a second plurality
of electrodes that includes a second plurality of ECG sensing
electrodes and a second plurality of therapy electrodes configured
to provide a defibrillating shock to the body of the patient, and a
waterproof connection pod electrically connected to the each of the
second plurality of electrodes. The waterproof connection pod
includes an elongated cable to electrically couple the waterproof
connection pod and the plurality of second electrodes to the
control unit, wherein the elongated cable has a length sufficient
to allow the control unit to remain in a dry location while also
allowing freedom of movement of the patient in an adjacent wet
environment with the plurality of second electrodes attached to the
body of the patient.
[0018] In accordance with an aspect of this embodiment, the length
of the elongated cable is at least three meters. In accordance with
another aspect of this embodiment, the elongated cable is
electrically coupled to the control unit by a removable connector.
In accordance with yet another aspect of this embodiment, the
second plurality of electrodes includes a pair of combined
ECG/therapy electrodes, each combined ECG/therapy electrode of the
pair of combined ECG/therapy electrodes including at least one ECG
sensing electrode and a therapy electrode mounted to a common
backing. In accordance with a further aspect of this embodiment,
each ECG/therapy electrode of the pair of combined ECG/therapy
electrodes includes two ECG sensing electrodes and the therapy
electrode mounted to the common backing.
[0019] In accordance with at least one embodiment, the wearable
medical device includes a user interface pod electrically coupled
to the control unit, and the accessory kit further comprises a
waterproof enclosure configured to receive the user interface pod
and protect the user interface pod during operation in the wet
environment.
[0020] In accordance with another embodiment, the wearable medical
device further includes a user interface pod configured to
wirelessly communicate with the control unit, the user interface
pod being housed in a waterproof case that is sealed to prevent the
ingress of water during operation in the wet environment.
[0021] In accordance with yet another embodiment, the first
plurality of electrodes are electrically coupled to a first
connection port of the control unit, and the removable connector is
configured to removably and electrically couple to a second
connection port of the control unit that is distinct from the first
connection port. In accordance with an aspect of this embodiment,
the second plurality of electrodes includes a pair of combined
ECG/therapy electrodes, each combined ECG/therapy electrode of the
pair of combined ECG/therapy electrodes including at least one ECG
sensing electrode and a therapy electrode mounted to a common
backing. In accordance with a further aspect of this embodiment,
each combined ECG/therapy electrode of the pair of combined
ECG/therapy electrodes includes two ECG sensing electrodes and the
therapy electrode mounted to the common backing, wherein at least
one of the pair of combined ECG/therapy electrodes further includes
a patient responsiveness button by which the patient can indicate
to the control unit that they are conscious.
[0022] In accordance with another embodiment of the present
invention, a wearable medical device is provided. The wearable
medical device comprises a plurality of ECG sensing electrodes
configured to sense an ECG of a patient, a plurality of therapy
electrodes configured to provide at least one defibrillating shock
to the body of the patient, and a control unit, electrically
coupled to the plurality of ECG sensing electrodes and the
plurality of therapy electrodes. The control unit is configured to
monitor the sensed ECG of the patient, and responsive to detection
of cardiac arrhythmia of the patient, to provide at least one
defibrillating pulse of energy to at least one of the plurality of
therapy electrodes. The control unit includes a master control unit
and a waterproof slave control unit, the master control unit being
physically separable from the waterproof slave control unit. The
waterproof slave control unit includes a plurality of capacitors
configured to store energy to provide the at least one
defibrillating pulse of energy to the at least one of the plurality
of therapy electrodes, and the master control unit is configured to
charge the plurality of capacitors prior to physical separation
from the waterproof slave control unit.
[0023] Still other aspects, embodiments, and advantages of these
exemplary aspects and embodiments are discussed in detail below.
Moreover, it is to be understood that both the foregoing
information and the following detailed description are merely
illustrative examples of various aspects and embodiments of the
present invention, and are intended to provide an overview or
framework for understanding the nature and character of the claimed
aspects and embodiments. Any embodiment disclosed herein may be
combined with any other embodiment in any manner consistent with at
least one of the aspects disclosed herein, and references to "an
embodiment," "some embodiments," "an alternate embodiment,"
"various embodiments," "one embodiment," "at least one embodiment,"
"this and other embodiments" 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. The
appearance of such terms herein is not necessarily all referring to
the same embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] 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:
[0025] FIG. 1a illustrates a wearable medical device, such as a
wearable defibrillator;
[0026] FIG. 1b illustrates a wearable medical device, such as a
wearable defibrillator, in accordance with an embodiment of the
present invention;
[0027] FIG. 2a illustrates a shower kit that may be used with the
wearable medical device of FIG. 1b in accordance with an embodiment
of the present invention;
[0028] FIG. 2b illustrates a shower kit that may be used with the
wearable medical device of FIG. 1b in accordance with another
embodiment of the present invention;
[0029] FIG. 2c illustrates an alternative control unit that may be
used with a wearable medical device in accordance with an
embodiment of the present invention;
[0030] FIG. 3a illustrates a combined ECG/therapy electrode system
for use with the shower kit of FIG. 2a;
[0031] FIG. 3b illustrates a combined ECG/therapy electrode system
for use with the shower kit of FIG. 2b;
[0032] FIG. 3c illustrates the manner in which the ECG/therapy
electrode system of FIGS. 3a and 3b may be worn by a patient;
[0033] FIG. 3d illustrates a combined ECG/therapy electrode system
for use with the shower kit of FIG. 2b in accordance with another
embodiment of the present invention;
[0034] FIGS. 3e and 3f illustrate alternative forms of a
water-resistant enclosure that may be associated with the shower
kits of FIGS. 2a and 2b;
[0035] FIG. 4a illustrates a waterproof wearable medical device in
accordance with an embodiment of the present invention;
[0036] FIG. 4b illustrates a waterproof wearable medical device in
accordance with another embodiment of the present invention;
[0037] FIG. 4c illustrates a waterproof wearable medical device in
accordance with a further embodiment of the present invention;
[0038] FIG. 5a illustrates a shower kit that may be used with the
wearable medical device of FIG. 1b in accordance with another
embodiment of the present invention;
[0039] FIG. 5b illustrates a shower kit that may be used with the
wearable medical device of FIG. 1b in accordance with a further
embodiment of the present invention;
[0040] FIG. 6a illustrates a control unit for use with a wearable
medical device in accordance with another embodiment of the present
invention; and
[0041] FIG. 6b illustrates a shower belt that may be used with the
control unit of FIG. 6a in accordance with another aspect of the
present invention.
DETAILED DESCRIPTION
[0042] This invention is not limited in its application to the
details of construction and the arrangement of components set forth
in the following 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
and equivalents thereof as well as additional items.
[0043] As discussed above, to provide protection against cardiac
arrest, patients that use a wearable medical device, such as a
wearable defibrillator, generally wear the device nearly
continuously while they are awake and while they are asleep.
However, there are periods of time where it may not be possible or
practical for them to wear the device, such as when taking a shower
or bathing. During such times, the patient may remove the device
when they get undressed to take a shower or bath, and may not put
the device back on until they have finished showering or bathing
and drying off. During this period of time, the patient is not
protected. To minimize the amount of time in which they are not
protected, many patients spend a minimal amount of time bathing.
Further, because the patient is not protected when the device is
removed from the patient's body, physicians typically recommend
that someone remain with the patient when the device is removed, to
render assistance in case of a medical emergency.
[0044] Applicants have appreciated there is need to protect
patients at risk of cardiac arrest when they are showering or
bathing, or even when swimming. To address this need, Applicants
have developed a number of different embodiments of a wearable
medical device, such as a wearable defibrillator, that are water
resistant, waterproof, or are designed in a manner in which certain
components of the wearable medical device that can be compromised
by contact with water or another liquid can be placed in a dry
location, yet still protect the patient.
[0045] FIG. 1a illustrates a wearable medical device, such as a
LifeVest.RTM. Wearable Cardioverter Defibrillator available from
Zoll Medical Corporation of Chelmsford, Mass. As shown, the
wearable medical device 100 includes a harness 110 having a pair of
shoulder straps and a belt that is worn about the torso of a
patient. The harness 110 is typically made from a material, such as
cotton, that is breathable, and unlikely to cause skin irritation,
even when worn for prolonged periods of time. The wearable medical
device 100 includes a plurality of ECG sensing electrodes 112 that
are attached to the harness 110 at various positions about the
patient's body and electrically coupled to a control unit 120 via a
connection pod 130. The plurality of ECG sensing electrodes 112,
which may be dry-sensing capacitance electrodes, are used by the
control unit 120 to monitor the cardiac function of the patient and
generally include a front/back pair of ECG sensing electrodes and a
side/side pair of ECG sensing electrodes. It should be appreciated
that additional ECG sensing electrodes may be provided, and the
plurality of ECG sensing electrodes 112 may be disposed at varying
locations about the patient's body.
[0046] The wearable medical device 100 also includes a plurality of
therapy electrodes 114 that are electrically coupled to the control
unit 120 via the connection pod 130 and which are capable of
delivering one or more therapeutic defibrillating shocks to the
body of the patient, if it is determined that such treatment is
warranted. As shown, the plurality of therapy electrodes 114
includes a first therapy electrode 114a that is disposed on the
front of the patient's torso and a second therapy electrode 114b
that is disposed on the back of the patient's torso. The second
therapy electrode 114b includes a pair of therapy electrodes that
are electrically coupled together and act as the second therapy
electrode 114b. The use of two therapy electrodes 114a, 114b
permits a biphasic shock to be delivered to the body of the
patient, such that a first of the two therapy electrodes can
deliver a first phase of the biphasic shock with the other therapy
electrode acting as a return, and the other therapy electrode can
deliver the second phase of the biphasic shock with the first
therapy electrode acting as the return. The connection pod 130
electrically couples the plurality of ECG sensing electrodes 112
and the plurality of therapy electrodes 114 to the control unit
120, and may include electronic circuitry. For example, in one
implementation the connection pod 130 includes signal acquisition
circuitry, such as a plurality of differential amplifiers to
receive ECG signals from different ones of the plurality of ECG
sensing electrodes 112 and to provide a differential ECG signal to
the control unit 120 based on the difference therebetween. The
connection pod 130 may also include other electronic circuitry,
such as a motion sensor or accelerometer by which patient activity
may be monitored.
[0047] As shown in FIG. 1a, the wearable medical device 100 may
also include a user interface pod 140 that is electrically coupled
to the control unit 120. The user interface pod 140 can be attached
to the patient's clothing or to the harness 110, for example, via a
clip (not shown) that is attached to a portion of the interface pod
140. Alternatively, the user interface pod 140 may simply be held
in a person's hand. The user interface pod 140 typically includes
one or more buttons by which the patient, or a bystander can
communicate with the control unit 120, and a speaker by which the
control unit 120 may communicate with the patient or the bystander.
In certain models of the LifeVest.RTM. Wearable Cardioverter
Defibrillator, the functionality of the user interface pod 140 is
incorporated into the control unit 120.
[0048] Where the control unit 120 determines that the patient is
experiencing cardiac arrhythmia, the control unit 120 may issue an
audible alarm via a loudspeaker (not shown) on the control unit 120
and/or the user interface pod 140 alerting the patient and any
bystanders to the patient's medical condition. The control unit 120
may also instruct the patient to press and hold one or more buttons
on the control unit 120 or on the user interface pod 140 to
indicate that the patient is conscious, thereby instructing the
control unit 120 to withhold the delivery of one or more
therapeutic defibrillating shocks. If the patient does not respond,
the device may presume that the patient is unconscious, and proceed
with the treatment sequence, culminating in the delivery of one or
more defibrillating shocks to the body of the patient.
[0049] The control unit 120 generally includes at least one
processor, microprocessor, or controller, such as a processor
commercially available from companies such as Texas Instruments,
Intel, AMD, Sun, IBM, Motorola, Freescale and ARM Holdings. In one
implementation, the at least one processor includes a power
conserving processor arrangement that comprises a general purpose
processor, such as an Intel.RTM. PXA270 processor and a special
purpose processor, such as a Freescale.TM. DSP56311 Digital Signal
Processor. Such a power conserving processor arrangement is
described in co-pending application Ser. No. 12/833,096, entitled
SYSTEM AND METHOD FOR CONSERVING POWER IN A MEDICAL DEVICE, filed
Jul. 9, 2010 (hereinafter the "'096 application") which is
incorporated by reference herein in its entirety. The at least one
processor of the control unit 120 is configured to monitor the
patient's medical condition, to perform medical data logging and
storage, and to provide medical treatment to the patient in
response to a detected medical condition, such as cardiac
arrhythmia.
[0050] Although not shown, the wearable medical device 100 may
include additional sensors, other than the ECG sensing electrodes
112, capable of monitoring the physiological condition or activity
of the patient. For example, sensors capable of measuring blood
pressure, heart rate, heart sounds, thoracic impedance, pulse
oxygen level, respiration rate, and the activity level of the
patient may also be provided.
[0051] FIG. 1b illustrates a wearable medical device, such as a
wearable defibrillator in accordance with an embodiment of the
present invention. The wearable medical device 100' is generally
similar in both form and function to the wearable medical device
100 described with respect to FIG. 1a, and thus only the
differences between the wearable medical device 100' of FIG. 1b and
the wearable medical device 100 of FIG. 1a are described in detail
herein. In accordance with a first embodiment, the user interface
pod 140 is electrically coupled to the control unit 120 via a
removable connector 222 shown more clearly in FIG. 2a (described in
detail further below), and the connection pod 130 is electrically
coupled to the plurality of ECG sensing electrodes 112 and the
plurality of therapy electrodes 114 via a removable and
water-resistant or waterproof connector 232. In this first
embodiment, the removable connector 222 permits the user interface
pod 140 to be disconnected and reconnected to the control unit 120.
The connector 232 includes two mating portions 232a and 232b that
permit the connection pod 130 to be separated from and re-attached
to the harness 110, the plurality of ECG sensing electrodes 112,
and the plurality of therapy electrodes 114. As described more
fully below with respect to FIG. 2a, in this first embodiment,
where the patient desires to shower or bathe, they may disconnect
the user interface pod 140 from the control unit 120, disconnect
the connection pod 130 from the harness 110, the plurality of ECG
sensing electrode 112, and the plurality of therapy electrodes 114,
and remove the harness 110. The patient may then reconnect the user
interface pod 140 to the control unit 120 and reconnect the
connection pod 130 to a plurality of ECG sensing electrodes 212 and
a plurality of therapy electrodes 214 associated with a shower kit
200.
[0052] In accordance with an alternative second embodiment, both
the user interface pod 140 and the connection pod 130 are
electrically coupled to the control unit 120 via removable
connectors 222, 223, respectively. In this second embodiment, the
connector 232 is not present and the plurality of ECG sensing
electrodes 112 and the plurality of therapy electrodes 114 are
directly connected to the connection pod 130. The removable
connectors 222, 223 permit the user interface pod 140 and the
connection pod 130 to be disconnected and reconnected to the
control unit 120. As described more fully below with respect to
FIG. 2b, in this second embodiment, where the patient desires to
shower or bathe, they may disconnect the user interface pod 140 and
the connection pod 130 from the control unit 120, remove the
harness 110, and reconnect the control unit 120 to the user
interface pod 140 and to a connection pod 230 and a plurality of
ECG sensing electrodes 212 and a plurality of therapy electrodes
214 associated with a shower kit 200'.
[0053] FIG. 2a illustrates a shower kit 200 that may be used with a
wearable medical device, such as the wearable medical device 100'
depicted in FIG. 1b to permit a patient to shower or bathe while
remaining protected from possibility of cardiac arrest. As
illustrated in FIG. 2a, the shower kit 200 includes a waterproof or
water-resistant enclosure 250 configured to receive the control
unit 120 and the connection pod 130. The enclosure 250 includes a
water resistant closure 253 which can be opened and sealed and
through which the control unit 120 and the connection pod 130 may
be inserted into and removed from the enclosure 250. The water
resistant closure 253 may be a press and seal closure, similar to
that of a Ziploc.RTM. seal plastic bag, a water-resistant zipper, a
roll-top closure, or even an elastic ring, such as a conventional
elastic band, as the present invention is not limited to any
particular type of closure. Enclosure 250 includes a first aperture
251 through which the removable connector 222 may be inserted to
electrically couple to user interface pod 140 to the control unit
120, and a second aperture 252 though which the mating portion 232a
of the removable connector 232 may be passed through and connected
to mating portion 232b. The first and second apertures 251 and 252
may be surrounded by an elastomeric seal that conforms to the
diameter of the cable passed therethrough to prevent the ingress of
water into the enclosure 250. In one embodiment, the enclosure 250
is formed from a transparent, flexible and water-resistant
material, such as a clear plastic, although other suitable
materials may be used. The use of a transparent flexible material
permits the patient to access any buttons 124 present on the
control unit 120, and permits the patient to view any messages that
may be provided on a display 121 of the control unit 120. The
enclosure 250 may include a strap 260 that is attached to the
enclosure 250 to permit the enclosure (with control unit and
connection pod 130 sealed therein) to be worn on the patient's body
during bathing, or alternatively, to be hung on a hook.
[0054] The shower kit 200 also includes an enclosure 270 in which
the user interface pod 140 can be received and protected from
moisture, where the user interface pod 140 is not itself
water-resistant. The enclosure 270 may be formed from a transparent
flexible material, such as plastic, that permits the patient to
view and access any buttons present on the user interface pod 140.
The enclosure 270 may include a water resistant closure (not shown)
to prevent any ingress of moisture. Alternatively, the enclosure
270 may be sealed with tape or an elastic band. Where the wearable
medical device 100' includes a user interface pod 140' that is
water-resistant or waterproof, the use of the enclosure 270 may be
omitted. Similarly, where the functionality of the user interface
pod 140 is integrated into the control unit 120, such as in the
LifeVest.RTM. model 4000 Wearable Cardioverter Defibrillator, the
enclosure 250 may include only a single aperture (i.e., the second
aperture 252 through which the mating portion 232a of the removable
connector is passed and connected to mating portion 232b).
[0055] As shown in FIG. 2a, the shower kit 200 also includes a
plurality of ECG sensing electrodes 212 and a plurality of therapy
electrodes 214 that are electrically coupled to the mating portion
232b of the waterproof or water-resistant connector 232. In
accordance with an aspect of the present invention, each of the
plurality of ECG sensing electrodes 212 may be conventional ECG
electrodes with an adhesive backing that are simply directly
attached to the body of the patient. Similarly, the plurality of
therapy electrodes 214 may also be conventional adhesively backed
electrodes that are of a sufficient dimension so as to be capable
of delivering one or more defibrillating pulses of energy to the
body of the patient. The plurality of therapy electrodes 214
includes a first therapy electrode 214a that can be adhesively
attached to the front of the patient's torso, and a second therapy
electrode that can be adhesively attached to the back of the
patient's torso 214b. It should be appreciated that because it may
be difficult for the patient themselves to attach the second
therapy electrode 214b to the back of their torso, the plurality of
therapy electrodes 214 may also be placed on the front of the
patient's torso at spaced apart positions, or on opposing lateral
sides of the patient's torso. For example, the first therapy
electrode 214a may be placed so that it is positioned below and
approximately centered on the patient's left breast, and the second
therapy electrode may be placed so that it is positioned above and
approximately centered on the patient's right breast. The plurality
of ECG sensing electrodes 212 could also be placed on the front of
the patient's torso with an ECG sensing electrode positioned on
each side of a respective therapy electrode 214a, 214b. Other
placements of the plurality of ECG sensing electrodes 212 and the
plurality of therapy electrodes 214 may also be used.
[0056] In accordance with an aspect of the present invention,
during those times where the patient is not bathing, the patient
may wear the wearable medical device 100' illustrated in FIG. 1b
while awake and while asleep. When it is necessary or desirable to
bathe, the patient may use the shower kit 200 in the following
manner to minimize the amount of time during which they are not
protected from cardiac arrest.
[0057] When the patient decides to bathe, the patient removes their
clothing, disconnects the connector 222 from the control unit 120
and disconnects the plurality of ECG sensing electrodes 112 and the
plurality of therapy electrodes 114 from the removable connector
232 and removes the connection pod 130 from the harness 110. The
patient may then remove the harness 110, insert the control unit
120 into the enclosure 250, push the connector 222 through the
aperture 251 in the enclosure and electrically couple it to the
control unit 120. The patient may then push the mating portion 232a
through the aperture 252 in the enclosure 250 and connect the
mating portion 232a to the mating portion 232b so that the
connection pod 130 is electrically coupled to the plurality of ECG
sensing electrodes 212 and the plurality of therapy electrodes 214.
The patient would then typically attach the plurality of ECG
sensing electrodes 212 to the front and back and sides of their
body, and then attach the therapy electrodes 214a and 214b to the
front and back of their body. Although the exact location of the
electrodes 212, 214 may vary, they may generally be attached to the
patient's body in locations similar to those of the wearable
medical device 100'. Where placement of electrodes 212, 214 in
locations similar to those of the wearable medical device 100' is
not practical or possible (e.g., due to the dexterity of the
patient, or due to the lack of an available caretaker to assist in
the attachment of the electrodes 212, 214), the electrodes 212, 214
may be placed in other locations about the patient's body. For
example, as discussed previously above the therapy electrodes 214
may be attached to opposing sides of anterior of the patient's body
(e.g., below the patient's left breast and above the patient's
right breast) with an ECG sensing electrode 212 attached on each
side of a therapy electrode. It should be appreciated that in other
embodiments, only two ECG sensing electrodes 212 may be
provided.
[0058] Depending upon whether a water resistant user interface pod
140' or a non-water resistant user interface pod 140 was used, the
patient may place the non-water resistant user interface pod 140
into the enclosure 270 and seal the enclosure. Where the
functionality of the user interface pod 140 is integrated into the
control unit 120, this step may simply be omitted. The enclosure
250 may then be sealed and the patient is now ready to bathe.
Because the patient is now protected, they may shower or bathe for
as long as they would like, or as frequently as desired.
[0059] It should be appreciated that the various steps described
above may be performed in an order different than that described
above. For example, to further reduce the amount of time the
patient is not protected, the patient may get undressed and place
the electrodes 212, 214 on their body while the wearable medical
device 100' and its associated harness 110 are still in position on
the patient's body. It should be appreciated that the shower kit
200 provides the patient with protection against cardiac arrest
while utilizing most of the components of the wearable medical
device 100 of FIG. 1a with minimal modification, and with minimal
added expense.
[0060] FIG. 2b illustrates an alternative shower kit 200' that may
be used with a wearable medical device, such as the wearable
medical device 100' depicted in FIG. 1b, to permit a patient to
shower or bathe while remaining protected from the possibility of
cardiac arrest. As the shower kit 200' is similar to the shower kit
200 illustrated in FIG. 2a, only differences will be described in
detail herein. As in the shower kit 200, the shower kit 200'
includes a waterproof or water-resistant enclosure 250 that is
configured to receive the control unit 120 and which includes a
water resistant closure 253 which can be opened and sealed. The
enclosure 250 may again be formed from a transparent, flexible
material, such as plastic, that permits a patient to view and
access portions of the control unit 120. However, in contrast to
the embodiment of FIG. 2a, the shower kit 200' includes a
connection pod 230 in addition to the plurality of ECG sensing
electrodes and the plurality of therapy electrodes 214. The
connection pod 230 is similar in function to the connection pod
130, and may include many of the same components, such as signal
acquisition circuitry, motion sensors or accelerometers, etc.
However, the connection pod 230 is specifically configured to be
water resistant and/or waterproof. This may be achieved in a well
known manner by sealing all openings in the connection pod 230 with
an elastomeric or other type of waterproof sealant, using
waterproof materials such as plastic or rubber for the body of the
connection pod 230, and by potting any electronic circuitry in the
connection pod 230 with a waterproof potting compound, such that if
any moisture were to penetrate the body of the connection pod 230,
the electronic circuitry inside would not be affected.
[0061] As in the shower kit 200 described above with respect to
FIG. 2a, the enclosure 250 of the shower kit 200' of FIG. 2b again
includes a first aperture 251 through which the removable connector
222 may be inserted to electrically couple the user interface pod
140 to the control unit 120 (where the functionality of the user
interface pod 140 is integrated into the control unit 120, such as
in the LifeVest.RTM. model 4000 Cardioverter Defibrillator,
aperture 251 may be omitted). The enclosure 250 also includes a
second aperture 252. However in this embodiment, the aperture 252
is dimensioned to receive the end of a cable that is electrically
coupled to the connection pod 230 and which includes a removable
connector 223' that is similar to the connector 223 used to
electrically couple connection pod 130 to the control unit 120 in
FIG. 1b. As in the shower kit 200, the first and second apertures
251 and 252 of the enclosure 250 of shower kit 200' may be
surrounded by an elastomeric seal that conforms to the diameter of
the cable passed therethrough to prevent the ingress of water into
the enclosure 250. The enclosure 250 may also include a strap 260
that is attached to the enclosure 250 to permit the enclosure (with
control unit 120 sealed therein) to be worn on the patient's body
during bathing, or alternatively, to be hung on a hook.
[0062] As in the shower kit 200, the shower kit 200' may also
include an enclosure 270 in which the user interface pod 140 can be
received and protected from moisture, where the user interface pod
140 is not itself water-resistant. Where the wearable medical
device 100' includes a user interface pod 140' that is
water-resistant or waterproof, or where the functionality of the
user interface pod 140, 140' is integrated into the control unit
120, the use of the enclosure 270 may be omitted. As in the shower
kit 200, the shower kit 200' includes a plurality of ECG sensing
electrodes 212 and a plurality of therapy electrodes 214 which may
be of the same type as those described with respect to FIG. 2a.
However, in shower kit 200,' these electrodes are directly attached
to the connection pod 230, rather than to a mating portion 232b of
the connector 232 shown in FIG. 2a.
[0063] In accordance with an aspect of the present invention,
during those times where the patient is not bathing, the patient
may wear the wearable medical device 100' illustrated in FIG. 1b
while awake and while asleep. When it is necessary or desirable to
bath, the patient may use the shower kit 200' in the following
manner to minimize the amount of time during which they are not
protected from cardiac arrest.
[0064] When the patient decides to bathe, the patient removes their
clothing, disconnects the connector 222 that is electrically
coupled to the user interface pod 140, 140' from the control unit
120 and disconnects the removable connector 223 that is
electrically coupled to the connection pod 130 from the control
unit 120. The patient may then remove the harness 110 with the
connection pod 130 still attached, insert the control unit 120 into
the enclosure 250, push the connector 222 through the aperture 251
in the enclosure 250 and electrically couple it to the control unit
120. The patient may then push the connector 223' that is attached
to the connection pod 230 through the aperture 252 in the enclosure
250 and connect it to the control unit 120 so that the control unit
120 is electrically coupled to the connection pod 230, the
plurality of ECG sensing electrodes 212, and the plurality of
therapy electrodes 214. The patient would then typically attach the
plurality of ECG sensing electrodes 212 to the front and back and
sides of their body, and then attach the therapy electrodes 214a
and 214 b to the front and back of their body. Although the exact
location of the electrodes 212, 214 may vary, they may generally be
attached to the patient's body in locations similar to those of the
wearable medical device 100'. As described previously with respect
to the embodiment of FIG. 2a, the electrodes 212, 214 may be placed
in alternative locations on the patient's body where assistance is
not available, or where the patient lacks dexterity, and in certain
embodiments, the plurality of ECG sensing electrodes 212 may
include only a single pair of ECG sensing electrodes. Depending
upon whether a water resistant user interface pod 140' or non-water
resistant user interface pod 140 was used, the patient may place
the non-water resistant user interface pod 140 into the enclosure
270 and seal the enclosure. The enclosure 250 may then be sealed
and the patient is now ready to bathe. Because the patient is now
protected, they may shower or bathe for as long as they would like,
or as frequently as desired.
[0065] It should be appreciated that the various steps described
above may be performed in an order different than that described
above. For example, to further reduce the amount of time the
patient is not protected, the patient may get undressed and place
the electrodes 212, 214 on their body while the wearable medical
device 100' and its associated harness 110 are still in position on
the patient's body. As with the first embodiment, the shower kit
200' provides the patient with protection against cardiac arrest
while utilizing most of the components of the wearable medical
device 100 of FIG. 1a with minimal modification, and with minimal
added expense.
[0066] FIG. 2c illustrates a control unit 120' in accordance with
an alternative embodiment of the present invention that may be used
to minimize the amount of time a patient is not protected before
and/or after bathing or showering. As shown, the control unit 120'
is similar to the control unit 120 described previously with
respect to FIG. 1b, in that it includes a display 121, one or more
buttons 124, and connection ports to receive removable connectors
222 and 223 (although it should be appreciated that in some
embodiments, the connection port to receive removable connector 222
may be omitted where the functionality of the user interface pod
140, 140' is integrated into the control unit 120'). In contrast to
previous embodiments, the control unit 120' includes an additional
connection port 224 that is configured to mate with the removable
connector 223' of the shower kit 200' of FIG. 2b. The connection
port 224 permits the removable connector 223' that is connected to
the connection pod 230 to be operatively connected to the control
unit 120' while the connection pod 130 is still operatively
connected to the control unit 120'. While the patient is still
wearing and protected by the wearable medical device 100', the
patient may remove their clothing, and attach the plurality of ECG
sensing electrodes 212 and the plurality of therapy electrodes 214
of the shower kit 200' to their body. The patient can then push the
connector 223' that is attached to connection pod 230 through the
aperture 252 in the enclosure 250 and connect it to the connection
port 224 on the control unit 120'. The patient may then disconnect
the connector 223 from the control unit 120' and remove the harness
110 from their body while protected by the electrodes of the shower
kit 200'.
[0067] In one embodiment, the control unit 120' can include
circuitry to detect the connection of connector 223' and connector
223 to the control unit 120' and to automatically switch between
using the plurality of ECG sensing electrodes 112 and the plurality
of therapy electrodes 114 that are connected to connection pod 130
and using the plurality of ECG sensing electrodes 212 and the
plurality of therapy electrodes 214 that are connected to
connection pod 230. For example, where the connector 223 is
connected to the control unit 120' and the connector 223' is
subsequently connected to connection port 224, the control unit
120' can detect that connection and automatically switch from using
the plurality of ECG sensing electrodes 112 and the plurality of
therapy electrodes 114 that are connected to connection pod 130 to
the plurality of ECG sensing electrodes 212 and the plurality of
therapy electrodes 214 that are connected to connection pod 230.
Where the connector 223 is subsequently disconnected and
reconnected to the control unit 120', the control unit 120' can
detect that connection and automatically switch from using the
plurality of ECG sensing electrodes 212 and the plurality of
therapy electrodes 214 that are connected to connection pod 230 to
using the plurality of ECG sensing electrodes 112 and the plurality
of therapy electrodes 114 that are connected to connection pod
130.
[0068] In an alternative embodiment, the control unit 120' may
include a user interface routine by which a user can manually
select which of the connection ports is active. For example, where
connector 223 and connector 223' are both connected to the control
unit 120', the user may select which one is to be used and then
remove the other connector. After showering or bathing, the patient
may dry themselves off, reconnect the connector 223 to the control
unit 120', and re-attach the harness 110 in position about their
body prior to changing their selection and disconnecting the
connector 223'.
[0069] In yet a further alternative embodiment, the control unit
120' may include a user interface routine that not only permits a
user to select which one of the connection ports is active, but to
also permit each of the connection ports to be active
simultaneously. This would allow the wearable medical device to be
used as a wearable cardioverter defibrillator that is not only
capable of monitoring and protecting the patient wearing the
wearable medical device, but also permitting the wearable medical
device to be used as Automatic External Defibrillator (AED) for
another. For example, where the patient wearing the wearable
medical device happens upon another person that appears to be
suffering a cardiac arrhythmia, the patient may attach the
electrodes 212 and 214 of the shower kit 200' to the body of the
other person, and connect the connector 223' to the connection port
224 of the control unit 120'. For such use, the wearable medical
device may include a pocket or pouch in which the shower kit 200'
may be stored. Upon connection of the connector 223' to the
connection port 224, the control unit 120' may monitor the ECG
signals of both the patient and the other person, and where a
shockable cardiac arrhythmia is detected on either the patient or
the other person, the control unit 120' may apply a defibrillating
shock to that person whose ECG signals correspond to the detected
cardiac arrhythmia. It should be appreciated that this embodiment
is not limited to the use of a shower kit that includes discrete
ECG sensing electrodes 212 and discrete therapy electrodes 214 such
as that shown in FIG. 2b, as combined ECG/therapy electrodes
(described in more detail below with respect to FIGS. 3a-d) could
alternatively be used.
[0070] Various alterations may be made to the shower kits 200 and
200' described with respect to FIGS. 2a and 2b. For example, FIGS.
3a-3c illustrate an alternative arrangement of ECG sensing
electrodes and therapy electrodes that may be used with a wearable
medical device to 100' to provide protection from cardiac arrest
during showering or bathing. As shown, rather than including a
plurality of discrete ECG sensing electrodes 212 and a plurality of
discrete therapy electrodes 214 (FIGS. 2a and 2b), a pair of
combined ECG/therapy electrodes 313a, 313b may be used instead.
Each combined ECG/therapy electrode 313a, 313b of the pair includes
a pair of ECG sensing electrodes 312 and a single therapy electrode
314a or 314b that are disposed on a common adhesive backing 309.
The combined ECG/therapy electrodes 313a and 313b are electrically
compatible with the plurality of ECG sensing electrodes 112, 212,
and the plurality of therapy electrodes 114, 214 of FIGS. 1a, 1b,
2a, and 2b, such that they may be used with the control unit 120 or
120' without modification.
[0071] The electrode system 300 of FIG. 3a includes a waterproof
connector portion 232b that is electrically coupled to each of the
combined ECG/therapy electrodes 313a, 313b and is configured to
mate with the connector portion 232a of FIG. 2a. Thus, the
electrode system 300 of FIG. 3a may be included in the shower kit
200 and used instead of the electrode system shown in FIG. 2a. The
electrode system 301 of FIG. 3b includes a connection pod 230 that
is electrically coupled to each of the combined ECG/therapy
electrodes 313a, 313b and to a removable connector 223' that is
configured to mate with the control unit 120 or 120'. The
connection pod 230 and the removable connector 223' may be
identical in form and function to those same elements described
with respect to FIG. 2b. Thus, the electrode system 301 of FIG. 3b
may be included in the shower kit 200' and used instead of the
electrode system shown in FIG. 2b.
[0072] FIG. 3c illustrates the manner in which the pair of combined
ECG/therapy electrodes 313a, 313b may be worn on a patient's body.
A first of the combined ECG/therapy electrodes 313a may be adhered
to the front of the patient's torso, and the second of the combined
ECG/therapy electrodes 313b (shown in dotted line form) adhered to
the back of the patient's torso so that the pair of combined
ECG/therapy electrodes 313a, 313b provides a front-to-back pair of
ECG sensing electrodes 312a, 312c, a side-to-side pair of ECG
sensing electrodes 312b, 312d, and front and back therapy
electrodes 314a, 314b in a manner similar to that of wearable
medical device 100 and 100'. Although not shown in FIG. 3c, it
should be appreciated that the pair of combined ECG/therapy
electrodes 313a, 313 b may be worn on the patient's body in other
locations. For example, ECG/therapy electrode 313a may be
positioned on one side of the patient's torso with the therapy
electrode 314a approximately centered below one armpit, and the
other ECG/therapy electrode 313b positioned on the other side of
the patient's torso with the therapy electrode 314b approximately
centered below the other armpit. Although each of the combined
ECG/therapy electrodes 313a, 313b illustrated in FIGS. 3a-3c is
shown as including a pair of ECG sensing electrodes 312a, 312b, and
312c, 312d, it should be appreciated that in other embodiments,
only a single ECG electrode may be included in each combined
ECG/therapy electrode 313a, 313b.
[0073] FIG. 3d illustrates yet an alternative arrangement of ECG
sensing electrodes and therapy electrodes that may be used with a
wearable medical device to 100' to provide protection from cardiac
arrest during showering or bathing. As in the embodiments of FIGS.
3a-3c, this embodiment again includes a pair of combined
ECG/therapy electrodes 313a, 313b that may be used instead of the
plurality of discrete ECG sensing electrodes 212 and the plurality
of discrete therapy electrodes 214 of FIGS. 2a and 2b. Each
combined ECG/therapy electrode 313a, 313b of the pair again
includes a pair of ECG sensing electrodes 312 and a single therapy
electrode 314a or 314b that are disposed on a common adhesive
backing 309. However, in this embodiment, at least one of the pair
of combined ECG/therapy electrodes 313a, 313b further includes a
patient responsiveness button 333 by which the patient can indicate
to the control unit 120' that they are conscious in the event of a
detected cardiac arrhythmia. This embodiment is particularly well
suited for those embodiments in which this functionality is
integrated on the control unit 120', rather than on the user
interface pod 140, 140'. In the event that a cardiac arrhythmia is
detected and the control unit 120' issues a warning that
application of a defibrillating shock is imminent, the patient may
press and hold the patient responsiveness button 333 to delay or
withhold the treatment sequence.
[0074] The electrode system 302 of FIG. 3d includes a water
resistant and/or waterproof connection pod 230 that is electrically
coupled to each of the combined ECG/therapy electrodes 313a, 313b
and to a removable connector 223' that is configured to mate with
the connection port 224 on the control unit 120'. The connection
pod 230 and the removable connector 223' may be similar in form and
function to those same elements described with respect to FIG. 2b.
In accordance with an aspect of the present invention, the
electrode system 302 of FIG. 3d is particularly well suited for use
with the control unit 120' described with respect to FIG. 2c, where
the connection port 224 need not be identical and backwards
compatible with the connection pod 130 and the plurality of ECG
sensing electrodes 112 and the plurality of therapy electrodes 114
associated with the harness 110. Thus the connection port 224 may
be configured to include the ability to receive a patient
responsiveness signal from the patient. The manner in which the
pair of combined ECG/therapy electrodes 313a, 313b of the electrode
system 302 may be worn on the patient's body is similar to that
described above with respect to FIGS. 3a-3d, and thus further
discussion is omitted herein.
[0075] FIGS. 3e and 3f illustrate some additional variations that
may be made to the enclosure 250 described with respect to FIGS. 2a
and 2b. For example, FIG. 3e illustrates an enclosure 350 in the
form of a belt or fanny pack that can be worn by the patient when
showering. In this embodiment, the user interface pod 140, 140' may
be attached to the belt of fanny pack for convenient access by the
patient. FIG. 3f illustrates an alternative embodiment in which the
enclosure 350' has the form of a backpack. In this embodiment, the
user interface pod 140, 140' may be attached to a shoulder strap of
the backpack.
[0076] FIG. 4a illustrates a waterproof wearable medical device,
such as a wearable defibrillator in accordance with another
embodiment of the present invention. The waterproof wearable
medical device 400 is generally similar in both form and function
to the wearable medical device 100 described with respect to FIG.
1a and the wearable medical device 100' of FIG. 1b. Accordingly,
only the differences are described in detail herein. As with the
wearable medical devices 100 and 100' of FIGS. 1a and 1b, the
waterproof wearable medical device 400 includes a harness 410
having a pair of shoulder straps and a belt that is worn about the
torso of the patient. The waterproof wearable medical device 400
also includes a plurality of ECG sensing electrodes 412 and a
plurality of therapy electrodes 414 that are electrically coupled
to a control unit 420 via a connection pod 430. In accordance with
an aspect of the present invention, the harness 410 is formed from
a waterproof material such as rubber or Neoprene.RTM., although
other water-resistant or waterproof materials may be used. The
connection pod 430 is similar in construction to the connection pod
230 described with respect to FIG. 2b, in that it is specifically
configured to be waterproof. For example, any openings in the
connection pod 430 are sealed with an elastomeric or other type of
waterproof sealant, the body of the connection pod 430 is formed
from a waterproof material, such as plastic, and any electronic
circuitry within the connection pod 430 is potted in a potting
compound so as to be unaffected by moisture. The plurality of ECG
sensing electrodes 412 and the plurality of therapy electrodes 414
may be similar to those used in the wearable medical device 100'
and described with respect to FIG. 1b (e.g., dry-sensing
capacitance ECG sensing electrodes and gelled therapy electrodes),
or otherwise. Although the plurality of therapy electrodes each
preferably include a gel-pack to release an impedance reducing
(i.e., electrically conductive) gel when it is determined that one
or more defibrillating shocks should be administered to the
patient, it should be appreciated that in certain environments,
such as in the salt water of the ocean or a salt water pool, the
conductivity of the water may itself be sufficient to ensure a low
impedance path between the electrodes and the patient's body.
[0077] Because waterproof materials such as rubber or Neoprene.RTM.
do not breathe as well as other materials, the medical device 400
may include a waterproof connector 432, similar to that described
with respect to connector 232 of FIG. 1b. The presence of the
waterproof connector 432 permits a patient to use the control unit
420 with the harness 410 and associated components of the device
400 when showering, bathing or swimming is desired, and to use the
control unit 420 with the harness 110 and associated components of
the device 100' of FIG. 1b at other times.
[0078] Although the control unit 420 is similar in function to the
control units 120, 120' described previously with respect to FIGS.
1-3, it is constructed to be waterproof. In this regard, the body
or case of the control unit 420 is formed from a waterproof or
water-resistant material, such as plastic and sealed to withstand
water. Joints in the body or case of the control unit 420 are
sealed with an elastomeric sealant or other type of waterproof
sealant, and any openings in the case or body of the control unit
420 (such as the opening in the case where the cable that connects
to connection pod 430 exits, or openings for buttons 124 and
display 121) are sealed with o-rings or an elastomeric sealant. In
further contrast to the wearable medical device described with
respect to FIGS. 1a and 1b, the waterproof wearable medical device
400 includes a wireless user interface pod 440 that wirelessly
communicates with the control unit 420. In this embodiment, both
the wireless user interface pod 440 and the control unit 420
include a wireless RF transceiver that communicate with one another
using a wireless communication standard and protocol that is
optimized for low cost and shorter distance (e.g., 10 meters) RF
communications, such as Bluetooth, Wireless USB, or ZigBee. It
should be appreciated that in other embodiments, the wireless user
interface pod 440 and the control unit 410 may communicate with one
another using communication standards and protocols that are
capable of communicating over greater distances, such as Wireless
Ethernet, or GSM.
[0079] Although the functionality of the wireless user interface
pod 440 is similar to that of the user interface pod 140, the
wireless user interface pod 440 is also constructed to be
waterproof. Thus, for example, the case or body of the wireless
user interface pod 440 is formed from a waterproof material such as
plastic, and any openings in the case or body are sealed with
o-rings or an elastomeric seal. Apertures in the case or body of
the wireless user interface pod 420 for a speaker or alarm may be
sealed with a water-resistant but sound permeable material, such as
GORE-TEX.RTM.. The case or body of the wireless user interface pod
440 may include a clip or hook and loop type fastener to permit the
user interface pod 440 to be attached to the harness 410.
[0080] FIG. 4b illustrates a waterproof wearable medical device,
such as a wearable defibrillator, in accordance with another
embodiment of the present invention. The waterproof wearable
medical device 401 is generally similar to the waterproof wearable
medical device 400 of FIG. 4a with one exception. Rather than
including a removable connector 432 to connect the connection pod
430 to the plurality of ECG sensing electrodes 412 and the
plurality of therapy electrodes 414, the device 401 includes a
removable and waterproof connector 423 that is similar to the
removable connector 223' described with respect to FIG. 2b, but
which forms a water-tight seal with the control unit 420. In this
embodiment, where the patient desires to shower, bathe, swim, or
otherwise immerse themselves in water, they may disconnect the
control unit 420 from the connection pod 130 of the harness 110 of
the wearable medical device 100' and connect it instead to the
connection pod 430.
[0081] FIG. 4c illustrates a waterproof wearable medical device,
such as a wearable defibrillator, in accordance with yet another
embodiment of the present invention. The waterproof wearable
medical device 402 is generally similar to the waterproof wearable
medical devices 400 and 401 of FIGS. 4a and 4b. However, the
waterproof wearable medical device 402 is designed to be worn
continuously by the patient, whether awake, asleep, or while
showering, bathing, or swimming. As a result, the connection pod
430 is permanently coupled to the control unit 420 and permanently
coupled to the plurality of ECG sensing electrodes 412 and the
plurality of therapy electrodes 414 in a waterproof manner.
[0082] FIG. 5a illustrates an alternative shower kit 500 in
accordance with an embodiment of the present invention in which
those elements of the wearable medical device 100' that could be
compromised by contact with water or another liquid, such as
control unit 120, may be placed in a secure and dry location while
the patient is showering or bathing. The shower kit 500 is similar
to the shower kit 200' described with respect to FIG. 2b, in that
it includes a plurality of ECG sensing electrodes 212 and a
plurality of therapy electrodes 214 which may be similar in
construction to the plurality of ECG sensing electrodes 212 and the
plurality of therapy electrodes 214 described with respect to FIG.
2b. The shower kit 500 also includes a connection pod 230 that is
similar to the connection pod 230 of FIG. 2b and which is
constructed to be water resistant and/or waterproof, and a user
interface pod 140, 140'. The user interface pod 140, 140' may be a
water resistant user interface pod 140' or a non-water resistant
user interface pod 140. However, in contrast to the shower kit
200', the cable 525 that electrically couples the connection pod
230 to the control unit 120 and the cable 535 that electrically
couples the user interface pod 140, 140' to the control unit 120
are of a sufficient length (e.g., approximately 3 meters or more)
to permit the control unit 120 to be placed outside of the shower
or bathing area in a dry location, and to remain connected while
allowing free movement of the patient, even in the event that the
patient falls down (e.g., should the patient experience cardiac
arrest). As depicted, the cable 525 has a removable connector 223'
that electrically couples the cable 525 to the control unit 120,
and the cable 535 has a removable connector 222 that electrically
couples the cable 535 to the control unit 120. The connectors 223'
and 222 may be identical to the connectors 223' and 222 of FIG. 2b,
respectively, and need not be water resistant. Where a
non-water-resistant user interface pod 140 is used, enclosure 270
may be used to protect the user interface pod 140 as previously
described. It should be appreciated that if the cable 535 that
electrically couples the user interface pod 140, 140' to the
control unit 120 is not of a sufficient length, a cable extender
may be provided. Although the cable extender would need to be of a
sufficient length to permit the control unit 120 to remain in a
secure and dry location while the patient was showering, this would
enable the control unit 120 and the user interface pod 140, 140' of
FIG. 1b to be used without modification.
[0083] It should be appreciated that the shower kit 500 may also be
used with the control unit 120' described above with respect to
FIG. 2c. For example, the removable connector 223' can be coupled
to the connection port 224 of the control unit 120' while the
connector 223 is still operatively coupled to the control unit 120'
to minimize the amount of time that the patient is not protected.
Although the plurality of ECG sensing electrodes 212 and the
plurality of therapy electrodes 214 shown in FIG. 5a are depicted
as being discrete electrodes, it should be appreciated that a pair
of combined ECG/therapy electrodes, such as those depicted in FIGS.
3a-c, may alternatively be used with an extended length cable 525
and either of control unit 120 or control unit 120'. Where the
control unit 120' includes a connection port 224 that is configured
to receive a patient responsiveness signal, a combined ECG/therapy
electrode system, such as the electrode system 302 of FIG. 3d may
similarly be used with an extended length cable to provide ECG
sensing electrodes, therapy electrodes, and a patient
responsiveness button 333 in a single electrode system.
[0084] FIG. 5b illustrates an alternative shower kit 501 in
accordance with an embodiment of the present invention in which
those elements of the wearable medical device which could be
compromised by contact with water or another liquid, such as
control unit 520, may be placed in a secure and dry location while
the patient is showering or bathing. The shower kit 501 is similar
to the shower kit 500 described above with respect to FIG. 5a, in
that it includes a plurality of ECG sensing electrodes 212 and a
plurality of therapy electrodes 214 which may be similar in
construction to those described with respect to FIG. 2b. In
addition, the shower kit 501 includes a connection pod 230 that is
similar to the connection pod 230 of FIG. 2b and is constructed to
be water resistant and/or waterproof. As in the shower kit 500, the
cable 525 that electrically couples the connection pod 230 to the
control unit 520 is of a sufficient length (e.g., approximately 3
meters or more) to permit the control unit 520 to be placed outside
of the shower or bathing area in a dry location, and to remain
connected while allowing free movement of the patient, even in the
event that the patient falls down (e.g., should the patient
experience cardiac arrest). As depicted, the cable 525 has a
removable connector 523 that electrically couples the cable 525 to
the control unit 520.
[0085] In the embodiment depicted in FIG. 5b, the control unit 520
communicates wirelessly with a wireless user interface pod, such as
the waterproof wireless interface pod 440 described with respect to
FIGS. 4a-c. In other respects, the control unit 520 is similar to
the control unit 120 of FIG. 1b, and like the control unit 120,
need not be waterproof or even water resistant. Although each of
the embodiments shown in FIGS. 5a and 5b is shown as including two
pairs of ECG sensing electrodes 212, it should be appreciated that
other embodiments may include only a single pair of ECG sensing
electrodes 212. Moreover, although the plurality of ECG sensing
electrodes 212 and the plurality of therapy electrodes 214 are
shown in FIG. 5b as being discrete electrodes, it should be
appreciated that a pair of combined ECG/therapy electrodes such as
those depicted in FIGS. 3a-c may alternatively be used.
[0086] FIG. 6a illustrates a control unit in accordance with a
further aspect of the present invention. Although the overall
functionality of the control unit 600 is similar to that of the
control units 120, 120', 420, and 520 described above, that
functionality is divided among different and separable units
including a first master control unit 610 and a second slave
control unit 620. As will be described in further detail below, the
master control unit 610 is not intended for use in wet
environments, such as a shower or bath, whereas the slave control
unit 620 is. For use in a wet environment, the master control unit
610 may be separated from the slave control unit 620 and left in a
secure and dry environment, while the slave control unit 620
remains with the patient to protect them in the event of cardiac
arrest.
[0087] The master control unit 610 includes circuitry 618 that
implements the main user interface for the control unit 600 and
controls such aspects as the touch screen display 621 and the user
interface buttons 624. The circuitry 618 in the master control unit
610 also handles the primary functions of arrhythmia detection and
cardiac event recording for the control unit 600. The master
control unit 610 further includes a main rechargeable battery pack
614 that provides power to the control unit 600, and powers both
the master control unit 610 and the slave control unit 620 when the
two are interconnected. The master control unit 610 includes a
wireless communication interface 601 for wirelessly communicating
with the slave control unit 620 when the two units are physically
separated from one another. The wireless interface 601 may also be
used to communicate with a wireless user interface pod, such as the
wireless user interface pod 440 described above with respect to
FIGS. 4a-c.
[0088] The slave control unit 620 includes capacitors 628 for
generating and storing a defibrillating charge, high voltage
charging circuitry (not shown) for charging the capacitors 628, and
circuitry for controlling the delivery of one or more
defibrillating shocks to the patient. The slave control unit 620
also includes a smaller, rechargeable battery 622 that provides
power to the slave control unit 620 during those periods of time
where the slave control unit 620 is separated from the master
control unit 610. In certain embodiments, the battery 622 may be
capable of charging the capacitors 628 to a voltage sufficient to
provide at least one defibrillating shock. The slave control unit
620 may also include a removable and waterproof connector 623 that
is similar in design and function to the connector 423 described
previously with respect to FIG. 4b. The slave control unit 620 is
purposefully designed to be waterproof and includes a wireless
communication interface 602 for communicating with the master
control unit 610 when the two units are physically separated. The
wireless communication interfaces 601, 602 may support any
bi-directional wireless communication standard and protocol,
including but not limited to wireless USB, wireless Ethernet,
ZigBee, Bluetooth, GSM, etc.
[0089] During operation in generally dry environments, the control
unit 600 would typically be connected to a harness similar to the
harness 110 depicted in FIG. 1b, and both the master control unit
610 and the slave control unit 620 would be coupled together and
operate as a single control unit. However, where the patient
desires to shower or bathe, the patient would remove the harness
110 and don a shower belt, such as the shower belt 690 illustrated
in FIG. 6b. The shower belt 690 is completely waterproof and
contains all the system elements needed to function as a
stand-alone wearable defibrillator. For example, the shower belt
690 includes a plurality of ECG sensing electrodes 612, front and
back therapy electrodes 614a, 614b, a waterproof connection pod 630
which may be similar to the waterproof connection pods 230 and 430
described previously, and a waterproof removable connector 623. The
waterproof removable connector 623 may be similar to the removable
connector 423 described previously with respect to FIG. 4b.
Although not shown, the shower belt 690 may include a simplified
user interface that is integrated into the belt 690 (e.g., to allow
the patient to indicate that they are conscious in response to a
detected cardiac arrhythmia), or alternatively, a wireless user
interface pod such as the wireless user interface pod 440 described
previously with respect to FIGS. 4a-c may be used.
[0090] After disconnecting the connection pod 130, removing the
harness 110, and donning the belt 690, the patient would connect
the connector 623 on the belt 690 to the slave control unit 620 and
separate the master control unit 610 from the slave control unit
620. The slave control unit 620 may then be attached to the belt
690, so that all elements needed to operate as a stand-alone
wearable medical defibrillator system are located on the belt 690
that is attached to the patient's torso. In some embodiments, the
belt 690 may include a pocket to receive the slave control unit 620
to again operate as a stand-alone wearable medical defibrillator.
During operation, the slave control unit 620 wirelessly
communicates with the master control unit 610 which is located in a
dry and secure environment (e.g., outside of the shower). Where the
master control unit 610 detects arrhythmia and determines that a
defibrillating shock should be delivered, the master control unit
610 sends a message to the slave control unit 620 to charge the
capacitors 628 via the battery 622. Once the capacitors 628 are
charged to the appropriate level, the slave control unit 620
controls the delivery of the defibrillating shock.
[0091] It should be appreciated that the slave control unit 620 may
include additional circuitry to allow it to protect the patient in
the event that communication with the master control unit 610 is
not possible. For example, the slave control unit 620 may include
circuitry to perform ECG monitoring and arrhythmia detection, as
well as capacitor charging and defibrillating shock delivery. Such
circuitry may be in addition to the circuitry contained in the
master control unit 610. In an alternative embodiment, and in
accordance with the teachings of the '096 application, the slave
control unit 620 can include circuitry capable of performing all
critical functions of the wearable medical device including the
monitoring of ECG information, the detection of cardiac
abnormalities, and the circuitry for generating and delivering one
or more defibrillating shocks to the body of the patient. In this
embodiment, the master control unit 610 would be responsible for
non-critical functions, such as event recording, storage, and
analysis, remote communication capabilities, full featured user
interface support, etc.
[0092] As discussed above, in the control unit 600, the slave
control unit 620 includes a rechargeable battery 622 that provides
power to the slave control unit 620 during those periods of time in
which it is separated from the master control unit 610. That
rechargeable battery 622 may be capable of charging the capacitors
628 to a voltage sufficient to provide at least one defibrillating
shock. However, the ability to charge the capacitors 628 to such a
voltage level may require a larger and more powerful battery than
would otherwise be needed to simply power the circuitry of the
slave control unit, thereby increasing the weight of the slave
control unit 620.
[0093] In accordance with a further aspect of the present
invention, the control unit 600 may include the ability to charge
the capacitors 628 to a voltage level sufficient to provide at
least one defibrillating shock prior to separation of the master
control unit 610 and the slave control unit 620. Such a `shower`
mode may be selected by the patient via the user interface of the
control unit 600. Once the capacitors 628 are fully charged, the
units may be separated from one another and the slave control unit
620 attached to the belt 690. After the patient has finished
showering or bathing and the master control unit 610 is reattached
to the slave control unit 620, the capacitors can be discharged.
This ability to pre-charge the capacitors 628 permits a smaller,
lighter weight battery to be used in the slave control unit 620,
thereby making it more portable.
[0094] Having thus described several aspects of at least one
embodiment of this invention, it is to be appreciated various
alterations, modifications, and improvements will readily occur to
those skilled in the art. Such alterations, modifications, and
improvements are intended to be part of this disclosure, and are
intended to be within the scope of the invention. Accordingly, the
foregoing description and drawings are by way of example only.
* * * * *