U.S. patent application number 13/608958 was filed with the patent office on 2013-01-03 for electromuscular incapacitation device and methods.
Invention is credited to Robert Randolph Bernard, Casey Hathcock, James Lee, Bruno D.V. Marino, Anita Mehta, Viet Thinh Pho, Kenneth J. Stethem.
Application Number | 20130003247 13/608958 |
Document ID | / |
Family ID | 46325946 |
Filed Date | 2013-01-03 |
United States Patent
Application |
20130003247 |
Kind Code |
A1 |
Stethem; Kenneth J. ; et
al. |
January 3, 2013 |
ELECTROMUSCULAR INCAPACITATION DEVICE AND METHODS
Abstract
Incapacitation of a mammalian subject results from the
application of a pulsed, low-power electric waveform. The waveform
is applied to the subject at a frequency and over a time period
sufficient to induce involuntary muscular contraction.
Additionally, the contraction causes limited lactic acid production
and is non- or minimally-injurious to the subject's tissues. A
device utilizing such a waveform is designed to control or
otherwise subdue an individual.
Inventors: |
Stethem; Kenneth J.;
(Bellevue, ID) ; Hathcock; Casey; (Lisle, IL)
; Marino; Bruno D.V.; (Brunswick, ME) ; Mehta;
Anita; (Plainfield, IL) ; Bernard; Robert
Randolph; (Marion, ID) ; Lee; James; (Monterey
Park, CA) ; Pho; Viet Thinh; (Anaheim, CA) |
Family ID: |
46325946 |
Appl. No.: |
13/608958 |
Filed: |
September 10, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12773304 |
May 4, 2010 |
8277328 |
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13608958 |
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11509086 |
Aug 23, 2006 |
7736237 |
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12773304 |
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11208762 |
Aug 23, 2005 |
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11509086 |
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10938553 |
Sep 13, 2004 |
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11208762 |
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10375075 |
Feb 28, 2003 |
6791816 |
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10938553 |
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10084972 |
Mar 1, 2002 |
6643114 |
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10375075 |
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Current U.S.
Class: |
361/232 |
Current CPC
Class: |
F41H 13/0025 20130101;
A22B 3/06 20130101; F41B 15/04 20130101; F41H 9/10 20130101; A01K
15/02 20130101; F41H 13/0087 20130101; F41H 13/0018 20130101 |
Class at
Publication: |
361/232 |
International
Class: |
F41B 15/04 20060101
F41B015/04 |
Claims
1. An apparatus for temporarily incapacitating a subject, the
apparatus comprising: a circuit for generating a pulsed, low-power
electric waveform having a frequency and over a time period
sufficient to induce involuntary muscular contraction with
non-injurious muscle effects; a plurality of electrical contacts
for delivering the waveform to a subject; and a switch to
selectively activate the circuit.
2.-37. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and incorporates by
reference herein in their entireties, the following: U.S.
Provisional Patent Application Ser. No. 60/794,919, filed on Apr.
24, 2006; U.S. Provisional Patent Application Ser. No. 60/794,325,
filed on Apr. 21, 2006; U.S. Provisional Patent Application Ser.
No. 60/764,787, filed on Feb. 2, 2006; U.S. Provisional Patent
Application Ser. No. 60/764,785, filed on Feb. 2, 2006; U.S.
Provisional Patent Application Ser. No. 60/736,603, filed on Nov.
14, 2005; and U.S. Provisional Patent Application Ser. No.
60/736,132, filed on Nov. 11, 2005.
[0002] This application also claims priority to and is a
continuation-in-part of U.S. patent application Ser. No.
11/208,762, filed on Aug. 23, 2005. U.S. patent application Ser.
No. 11/208,762 is a continuation-in-part of U.S. patent application
Ser. No. 10/938,553, filed on Sep. 13, 2004, now abandoned; which
is a continuation of U.S. patent application Ser. No. 10/375,075,
filed on Feb. 28, 2003, which issued Sep. 14, 2004, as U.S. Pat.
No. 6,791,816; which is a continuation-in-part of U.S. patent
application Ser. No. 10/084,972, filed on Mar. 1, 2002, which
issued Nov. 4, 2003, as U.S. Pat. No. 6,643,114; all of which are
incorporated by reference herein in their entireties.
FIELD OF THE INVENTION
[0003] The present invention relates generally to devices used to
control and subdue a subject and, more specifically, to devices
that deliver an electric waveform to a subject to induce
electromuscular incapacitation (EMI).
BACKGROUND OF THE INVENTION
[0004] A number of non-lethal devices exist to subdue and control
an individual, a group of individuals, or a crowd. The devices are
varied in type and application, and have increased in use
throughout the last decade. Common devices include the bean bag
projectile, various types of pepper sprays, water cannons, rubber
bullets and a variety of materials fired from conventional
firearms. More recently, the use of conducted electric current to
incapacitate an individual has become widely used, but has been
confined generally to pistol trigger-based platforms that project
puncturing barbs or needles as the delivery medium of the EMI
stimulus. While the effectiveness and safety of the devices vary,
this stun device or "stun gun" genre has received widespread
acceptance and use.
[0005] Notwithstanding the history of stun devices, there has been
little improvement or change in the EMI approach. There have been
few reports of biologically-based studies that characterize
specific responses to stun device stimuli or to health effects of a
given stun device output with reference to nerves and muscle, both
of which mediate the EMI response. Very little objective laboratory
data is available describing the physiological effects of stun
devices. As a result of the increased usage and deployment of EMI
devices, a growing number of individuals are presenting electrical
injuries related to the use of such devices and a growing number of
morbidities and mortalities are being observed. Understanding the
physiologic effects of high voltage, variable DC current electrical
injuries will allow the mechanisms contributing to the observed
morbidity and mortality to be understood and devices properly
evaluated for potentially injurious side effects.
[0006] Electrical discharge produces a complex set of injuries
including thermal burns, cell membrane damage and rupture, and
macromolecule (protein and glycosaminoglycans) denaturation or
alteration. The nature and extent of the injuries appears to be
related, at least in part, to the strength and duration of the
discharge, its anatomic location and path through the tissues of
the body, and the characteristics of the current applied (i.e., AC,
DC, mixed). The organ- and organism-level effects may include skin
burns, skeletal muscle death, cardiac dysrhythmia, osteocyte and
osteoblast death, blood vessel endothelium dysfunction, etc.
Moreover, the application of electric currents to a live subject
may cause acidosis, due to incomplete or inconsistent muscular
contraction. Acidosis occurs when the body is incapable of properly
clearing lactic acid build-up within areas of the body, a condition
that may lead to death in extreme cases. Some types of current
(e.g., direct current, DC) can cause little or no injury at low
levels and increasing amounts of damage and disruption of muscle
control at higher levels.
[0007] One feature of typical stun devices is the expectation of
instantaneous and full incapacitation upon completion of the
circuit. In the prior art, the EMI stimulus was designed to elicit
a fast target response, typically above the "let-go response,"
after which no further increases in incapacitation are possible,
other than lengthening the duration of the incapacitation while the
circuit is maintained by repeated trigger pulls. In many cases,
instantaneous full incapacitation may not be required or warranted,
particularly in cases with vulnerable populations in which short
and/or repeated periods of contact with an EMI stimulus may be
preferable, or in cases where full incapacitation would put the
victim at danger of falling and sustaining an injury.
SUMMARY OF THE INVENTION
[0008] It is contemplated by the inventors that studies of the
physiologic effects of EMI stimuli may be crucial to developing an
improved EMI device with non-injurious features for both healthy
and vulnerable populations. Certain biologically-based studies may
be used, for example, to improve the actual hardware-delivered EMI
stimulus leading to more effective and enhanced incapacitation with
less chance of permanent nerve and muscle injury to a subject. This
would be particularly useful information, especially regarding
subjects who may be at risk for adverse reaction to a full stun
incident including the elderly, mentally disturbed, pregnant, very
young, intoxicated, and otherwise health-compromised individuals.
It would be highly desirable to have an optimized,
non-subcutaneous, point-of-contact EMI capacity suitable for use on
a wide variety of persons and in various circumstances.
[0009] The present invention offers improvements over typical stun
gun systems by offering a locationally precise point-of-contact
capability of variable duration and incapacitation effect using an
improved EMI stimulus based on biologically relevant studies.
[0010] An optimized electrical output signal is based on a
frequency cycle from greater than about 50 to 1000 Hz, a voltage of
from about 100V to 100 kV, and total charge output of from about 20
to 1,500 .mu.Coulombs affording effective and non-injurious
incapacitation relative to systems operating with typical
parameters. Experimental indications of the improved EMI stimulus
are provided hereinbelow. Due, however, to the beneficial results
associated with the optimized electrical output signal, the signal
and associated signal-generating circuitry can be used in any
delivery device or apparatus including, but not limited to,
projectile firing stun guns, batons, and similar devices.
[0011] The improved device utilizes electrical current waveforms to
maximize neuromuscular mechanisms responsible for EMI and minimize
local tissue damage or deleterious and non-reversible general
responses which result from local tissue damage.
[0012] Objects of the invention include delivery of optimum
electrical waveforms and amplitudes for EMI that elicit the desired
response with minimal or complete absence of permanent nerve and
muscle injury. Because skeletal muscle, cardiac muscle, and nerve
tissues are most sensitive to electrical forces used to determine
the effect of EMI, the survival and function of these tissues is
important over a range of time after electrical shock to provide
assurances for measures of safety and health effects.
[0013] In one aspect, the invention relates to an EMI device for
providing an electrical stimulus signal with an optimum electric
waveform and amplitude to produce selectively an electric charge of
stunning capability. Embodiments of the above aspect may include
the following, individually and in various combinations: (a) any of
the series of pulses having different frequencies out of which at
least one pulse has a repetition rate in the range of about 5-1000
pulses per second (i.e., Hz); (b) pulse duration that ranges from
about 3-1000 microseconds; (c) pulse ionization potential that
delivers charge in the range of about 20 microcoulomb to 1500
microcoulomb; (d) pulses which vary in shape such as sinusoidal,
square, triangular or sawtooth; (e) energy content which ranges
from about 0.001-0.5 joule/pulse; RMS current in ranges smaller
than about 400 mA; (g) duty cycle of about 0.005% to 5%; (h)
circuitry that utilizes solid state semiconductors for pulse power
switching for improved switching speed, high reliability, low
degradation, lengthened life, low cost, high repetition rate, low
losses, and high voltage and current rating over conventional
capacitor discharge topologies (e.g. thyratron, ignitron, or spark
gap); (i) at least two electrodes; and (j) voltage in the range of
about 100 V-100 kV.
[0014] In another aspect, the invention relates to a method of
temporarily incapacitating a subject, the method having the steps
of generating a pulsed, lower power electric waveform, and applying
the pulsed, low-power electric waveform to a subject at a frequency
and over a time period sufficient to induce involuntary muscular
contraction with non-injurious muscle effects. In embodiments of
the above aspect, due to application of the waveform, the
non-injurious muscle effect is a myoglobin concentration value
substantially unchanged relative to a control. In other
embodiments, the non-injurious muscle effect is a CK-MB
concentration value substantially unchanged relative to a control,
and/or a troponin I concentration value substantially unchanged
relative to a control. In other embodiments, due to application of
the waveform, the involuntary muscular contraction results in
limited lactic acid production, which may be a lactic acid
concentration of a subject that is substantially unchanged relative
to a control.
[0015] Certain embodiments utilize a waveform frequency in a range
of about 40 Hz to about 80 Hz, more specifically, about 50 Hz to
about 70 Hz, and even more specifically 67 Hz and/or 60 Hz. In
other embodiments of the above aspect, the involuntary muscular
contraction is characterized by substantially complete tetany or
partial tetany. In certain embodiments, the waveform utilizes a
peak voltage of less than about 1 kV and/or a peak current of less
than about 1 A. In other embodiments, the time period of the
waveform is about 5 ms, and its duty cycle may be between about
0.005% to about 5%.
[0016] In another aspect, the invention relates to an apparatus for
temporarily incapacitating a subject, the apparatus including a
circuit for generating a pulsed, low-power electric waveform having
a frequency and over a time period sufficient to induce involuntary
muscular contraction with non-injurious muscle effects, a plurality
of electrical contacts for delivering the waveform to a subject,
and a switch to selectively activate the circuit. In certain
embodiments of the above aspect, each contact may be at least one
of a pad, a button, a nub, a prong, a needle, and a hook. Other
embodiments include a release mechanism for releasing the plurality
of contacts from the apparatus. In still other embodiments of the
above aspect, the contacts deliver the waveform to a subject
subcutaneously, or deliver the waveform to an outer surface of a
subject. Other embodiments include an elongate body having a first
end and a second end, wherein the contacts are located proximate
the first end and the switch is located proximate the second
end.
[0017] In yet another aspect, the invention relates to a pulsed,
low-power electric waveform adapted for temporarily incapacitating
a subject, the waveform including a substantially square shape
profile, a frequency having a value in a range of about 40 Hz to
about 80 Hz, and a peak voltage of about less than about 1 kV,
wherein applying the waveform to a subject over a time period
induces involuntary muscular contraction with non-injurious muscle
effects. In certain embodiments of the above aspect, due to
application of the waveform to a subject, the non-injurious muscle
effect includes a myoglobin concentration value substantially
unchanged relative to a control, a CK-MB concentration value
substantially unchanged relative to a control, and/or a troponin I
concentration value substantially unchanged relative to a control.
In other embodiments, due to application of the waveform to a
subject, the involuntary muscular contraction results in limited
lactic acid production, and/or a lactic acid concentration of a
subject that is substantially unchanged relative to a control.
[0018] In other embodiments of the above aspect, the waveform
frequency may be a value in a range of about 50 Hz to about 70 Hz,
or may be about 67 Hz, or about 60 Hz. In other embodiments, the
involuntary muscular contraction may be characterized by
substantially complete tetany or partial tetany. In certain
embodiments, the waveform utilizes a peak voltage of less than
about 1 kV and/or a peak current of less than about 1 A. In other
embodiments, the time period of the waveform is about 5 ms, and its
duty cycle may be between about 0.005% to about 5%.
BRIEF DESCRIPTION OF THE FIGURES
[0019] The foregoing and other objects, features, and advantages of
the present invention, as well as the invention itself, will be
more fully understood from the following description of various
embodiments, when read together with the accompanying drawings, in
which:
[0020] FIG. 1A is a schematic perspective view of an EMI device in
accordance with one embodiment of the present invention;
[0021] FIG. 1B is an exploded schematic perspective view of the EMI
device of FIG. 1A;
[0022] FIG. 1C is a partial schematic side view of an EMI device in
accordance with one embodiment of the present invention;
[0023] FIGS. 2A-2D are schematic side views of EMI device
electrodes in accordance with several embodiments of the present
invention;
[0024] FIG. 3A-3B are electrical schematic diagrams of an electric
waveform generator in accordance with one embodiment of the present
invention;
[0025] FIG. 3C is a schematic side and end view of a high voltage
bobbin for use in an electric waveform generator circuit in
accordance with one embodiment of the present invention;
[0026] FIGS. 4A-4I are plots of test results of a signal generated
by an EMI device utilizing the circuit of FIGS. 3A-3B;
[0027] FIGS. 5A-5C are plots of stimulation frequencies for an EMI
device manufactured in accordance with one embodiment of the
present invention;
[0028] FIGS. 6A-6D are graphs of the acute effects on a stimulated
limb of a subject, wherein the subject is stimulated by an
electrical waveform generated by the circuit of FIGS. 3A-3B;
[0029] FIGS. 7A-7D are graphs of the acute effects on a
non-stimulated limb of a subject, wherein the subject is stimulated
by an electrical waveform generated by the circuit of FIGS.
3A-3B;
[0030] FIGS. 8A-8D are graphs of the acute effects on various blood
parameters of a subject stimulated by an electrical waveform
generated by the circuit of FIGS. 3A-3B;
[0031] FIGS. 9A-9D are graphs of the long-term effects on a
stimulated limb of a subject wherein the subject is stimulated by
an electrical waveform generated by the circuit of FIGS. 3A-3B;
[0032] FIGS. 10A-10D are graphs of the long-term effects on a
non-stimulated limb of a subject, wherein the subject is stimulated
by an electrical waveform generated by the circuit of FIGS. 3A-3B;
and
[0033] FIGS. 11A-11D are graphs of the long-term effects on various
blood parameters of a subject stimulated by an electrical waveform
generated by the circuit of FIGS. 3A-3B.
DETAILED DESCRIPTION
[0034] One embodiment of a hand-held EMI device 10 in a baton
configuration is depicted in FIG. 1A. The device 10 is constructed
of an elongate, generally hollow shaft 12 having a discharge end
cap 14, with two electrodes E mounted thereon. Extending from the
discharge end cap 14 is an impact portion 16, which allows the
device 10 to be used for close-quarters offensive or defensive
maneuvers. The impact portion 16 is generally hollow to contain the
EMI device's electronic components, and also may include impact
ribs 18 extending lengthwise along the outer circumference of the
impact portion 16. The impact ribs 18 provide additional structural
reinforcement along the length of the impact portion 16, and may be
integrally formed with the impact portion 16. Alternatively, the
impact ribs 18 may be constructed of a different material and
secured to the impact portion 16 by any mechanical or chemical
means.
[0035] A button or switch 20 that controls the internal EMI
circuitry is located on the device 10, usually near a handle
portion 22, such that the switch 20 may be activated by a user's
thumb or finger, while the device 10 is being grasped. A butt end
portion 24 is located at the end of the device 10 opposite the
discharge end cap 14. The butt end portion 24 may include screw
threads (FIG. 1B) or other structure for securing a butt end cap
26. The butt end cap 26 may be removed to allow access to, for
example, batteries or other internal electronic components. The
butt end cap 26 may also function as a weighted counterbalance to
allow the device 10 to be held and controlled with ease. For
example, a longer device would allow a user to apply an EMI
waveform (via the electrodes E) at a further distance from a
target, but may make the device more awkward to control. A weighted
butt end cap would offset the weight of such an elongated
device.
[0036] FIG. 1B depicts an exploded perspective view of the device
10 of FIG. 1A. The device 10 is constructed of two substantially
identical main outer components 12a, 12b joined lengthwise to form
a solid shaft 12, though other suitable configurations and
constructions are contemplated. An electric stun module 28 is
contained within the shaft 12. The stun module 28 may be replaced
with alternate modules 30, e.g., high intensity light-emitting
devices, sound-emitting devices, irritant spray discharge devices,
etc. Such optional modules, and other optional components (exterior
shaft cutting or abrading surfaces, lights, etc.) may be
incorporated in embodiments of the device described herein. Such
optional elements are described in more detail in U.S. patent
application Ser. No. 11/208,762; U.S. patent application Ser. No.
10/938,553; U.S. Pat. No. 6,791,816; and U.S. Pat. No. 6,643,114,
the disclosures of all of which are incorporated by reference
herein in their entireties.
[0037] A battery pack 26 provides the power to operate the electric
stun module 28, or any alternate modules 30, as required. If
required or desired, an internal heat sink 32 may also located
within the shaft 12. One or more lights or LEDs 34 may be visible
through the wall of the shaft 12, and may be wired to operate as
desired for a particular application. For example, the LED 34 may
be constant-on, flashing, multi-colored, etc., as desired to
provide visual indication of the status of the device ("low-power,"
"operating," "service required," "circuit failure," "ready," etc.).
An additional button or switch 36 may also be located on the device
10 and may be used as a safety, requiring both buttons 20, 36 to be
pressed for the electric stun module 28 to be activated.
Alternatively or additionally, one of the buttons may function as
an ON switch, with the second button functioning as an OFF switch.
Either or both of the buttons may be used to increase the
intensity, duration, etc., of the electric output of the device 10.
Other uses and functionality are apparent to one of ordinary skill
in the art.
[0038] More specifically, and with respect to a particular
embodiment, depressing and releasing the button 20 turns the
electrical circuit on, and the waveform is generated. Depressing
and releasing the button 20 a second time turns the device off.
When the device is on and the waveform is being generated, the
button 36 operates as a momentary switch, temporarily breaking the
circuit while the button 36 is depressed. Releasing the button 36
turns the device back on.
[0039] Although a baton-type stun device is depicted in FIG. 1A,
other stun device platforms are also contemplated. For example, the
circuit depicted in FIGS. 3A-3B may also be utilized in the "stun
gun" platform, wherein tethered darts are launched or otherwise
shot from a usually hand-held, pistol-type deployment device. FIG.
1C depicts such an embodiment of a releasable stun device 50. The
device 50 consists of a shaft 52, which may be hollow to contain
the desired electrical components, as depicted in FIG. 1B. Impact
ribs 54 may be located on the outer surface of the shaft 52, if
desired, or the shaft may define a portion of the "barrel" of a
stun gun. A releasable end cap 56, or electrodes E' themselves may
be releasable from the end of the shaft 52. The electrodes E' are
connected via conducting tethers 60 to the internal circuitry of
the device 50, allowing the EMI device 50 to be utilized at a
distance from a subject. The releasable end cap 56 or electrodes E'
may be forcibly expelled 62 from the shaft 52 by some launching
mechanism, such as a spring or pneumatic charge, or may be
passively released once the barbed electrodes E' attach to the skin
or clothing of a subject. Additional details regarding types of
electrodes are described with regard to FIGS. 2A-2D, below. Other
devices for launching tethered electrodes are known in the art.
[0040] Additionally, the circuit of FIGS. 3A-3B may be utilized in
other implements that appear less "offensive" in nature than a gun
or baton. Such applications include belts worn by inmates in
environments that require them to appear in public (e.g.,
courthouses, transport vehicles, etc.) while securing the public
against any harmful or threatening actions by the inmate. hi such
applications, the stun belt could be worn under clothing to prevent
it from being visible by persons who may be influenced by its
presence (a jury pool, for example). Such a device could be
operated remotely to safeguard the public from the individual.
Additionally, electrodes may be located on the fingertips or palm
of an electrically insulated glove to provide for more discreet
deployment by a user. In such a case, the battery pack and
circuitry may be located remote from the electrodes (e.g., on a
belt or in a pocket), and connected thereto with wires routed
through clothing. The user could simply activate the circuit while
touching a subject to achieve the desired incapacitation response.
In the belt and glove embodiments, the low profile electrode
embodiments depicted in FIGS. 2A and 2D (described below) may be
useful to allow the device to be used without prolonged penetration
of the skin of a wearer (in the case of the belt) or accidental
penetration of the skin of a user (in the case of the glove).
[0041] FIGS. 2A-2D depict various embodiments of the electrodes
that may be utilized with an EMI device of the present invention.
FIG. 2A depicts electrodes 100, 102 having a generally convex outer
shape and low overall profile. The electrodes 100, 102 may be
round, oblong, or any other shape desired for a particular
application. The radius of curvature of the outer surface of the
electrodes 100, 102 may vary depending on application, but
generally may have a curvature that prevents penetration of the
skin. The electrodes 100, 102 are depicted in this figure located
on a discharge end cap 14', but, as noted above, these low profile
electrodes may be utilized in other devices where penetration of
the skin by electrodes is neither required nor desired. FIG. 2B
depicts electrodes 104, 106 having a generally barbed or hooked
shape. In certain applications, especially those that require the
electrodes to remain fixed to the subject, electrodes that
penetrate skin or clothing may be required. Such electrodes may be
barbed or otherwise hooked to prevent inadvertent or deliberate
removal by a subject. During use, the barbs or hooks penetrate the
clothing and/or skin of a subject and are retained thereon,
allowing a user to continue to deliver incapacitating waveforms,
should the subject attempt to move away from the device. The barbed
electrodes 104, 106 are also useful for embodiments of the stun
device that utilize a releasable end cap 56' and fire the
electrodes at a subject or otherwise release the electrodes from
the body of the device, as described with regard to FIG. 1C.
Moreover, although the barbed electrodes are described above as
used in conjunction with releasable discharge heads, or as being
themselves releasable, barbed electrodes may also be used with
non-releasable embodiments of a stun device.
[0042] FIG. 2C depicts blunt-tipped electrodes that may contact the
skin or clothing of a subject without a substantial risk of
penetration the surface. The electrodes 108, 110 may be mounted on
springs within the discharge end cap 14', so as to retract when
pressed against a subject, thus limiting or preventing penetration.
FIG. 2D depicts another embodiment of low-profile electrodes 112,
114, similar to the electrodes of FIG. 2A, but with a larger
surface area, such that penetration of the skin surface of a
subject is mitigated or eliminated. The electrodes 112, 114 are
depicted in this FIG. located on a discharge end cap 14', but, as
noted above, these low profile electrodes may be utilized in other
devices where penetration of the skin by electrodes is neither
required nor desired.
[0043] An exemplary electrical system utilized in the stun module
28 is depicted in FIGS. 3A-3B. The circuit of FIGS. 3A-3B employs
silicon controlled rectifier (SCR) technology, rather than using
the spark gap principle as in other devices, although circuits
utilizing spark gap principle may be used in certain embodiments of
the device. It will be understood that the circuit of FIGS. 3A-3B
may be used without a replaceable module, e.g., to replace stun
circuits in conventional, permanently-wired stun devices.
[0044] The circuit of FIG. 3A receives power from the two contacts
E1 and E2, which provide power from the battery pack 26, which may
be a 12-volt lithium ion battery, an equivalent, or other power
source. Electrical power passes through a fuse Fl and filtering
circuit C1, C2, and R1 to a bridge driver controller integrated
circuit U1, which contains an oscillator and a pair of metal oxide
semiconductor field effect transistor (MOSFET) drivers. R4 and C3
set a switching frequency for a high-voltage switching converter.
Two MOSFET devices Q1 and Q2 are switches, which alternately charge
and discharge the capacitor group C5A through C5D to drive the high
voltage transformer T1. Coil L2 limits the charging current. The
transformer steps up the voltage to a desired level, e.g., a 290:1
ratio. The alternating current from the transformer T1 is rectified
by high voltage diodes CR101 through CR108, employed in a
bridge-type circuit. Output from the diode bridge CR101 through
CR108 charges the capacitor C103.
[0045] Primary voltage from the transformer T1 is sensed by U201
and C201. When voltage at the primary of the transformer T1 exceeds
a predetermined limit, a fast gate driver circuit built around Q201
provides a pulse of current to the gate of SCR CR201, turning the
SCR on. This circuit provides a rapid turn-on for the SCR for
minimal losses between the capacitor C103 and the step-up side of
the transformer T1. Once triggered, the SCR stays on until the
output capacitor C103 discharges to a low voltage. Primary input
leads of a high voltage transformer T2 are soldered to E3 and E4.
The use of an SCR to control the rapid switching of the circuit,
rather than a conventional spark gap switch, results in a device
having a much longer lifespan than the conventional spark gap
driven device. The above-described circuit as shown in FIG. 3A of
the drawings is preferably "potted" or encapsulated in a plastic
resin or other suitable material for greater durability when the
device 10 is used as an impact weapon. In addition to ON/OFF
control provided by the switches, the circuit may also include a
time delay function, which allows the circuit to maintain the
generated waveform for a predetermined period each time a switch is
pressed. This time period may be factory- or user-configurable, as
desired.
[0046] More specifically, and with respect to a particular
embodiment, the unit is a high-voltage switching converter, which
produces an output voltage high enough to cause an arc across a
pair of electrodes. The converter operates from a 12 VDC lithium
ion battery. It produces a 50 kV pulsed output, limited by the
breakdown of air across a pair of electrodes. The arc, or breakdown
of air, occurs at about 60 Hz and creates a continuous stream of
bright intense light and a loud audible noise. In this embodiment,
capacitors C101 and C102, and resistor R4 are not present in the
circuit of FIG. 3A.
[0047] The input consists of a resettable fuse, F1, followed by a
2200 .mu.F electrolytic capacitor, C1, The resettable fuse performs
two functions: it limits inrush current during application of input
power and provides protection from reverse battery polarity. The
capacitor provides a low impedance source and filters the converter
switching current. With a fully-charged battery, the input current
is 0.8 A and draws less than 10 W of input power. As the battery
drains, the arc rate reduces, which results in reduction of input
power. See Table 1, below, for the arc rate as a function of
battery voltage. A fully charged battery will last one hour with
continuous operation. Alternatively, feedback circuitry may be
utilized to govern the repetition rate of the oscillator and,
therefore, regulate the frequency of the generated signal to a
constant level.
TABLE-US-00001 TABLE 1 Arc Rate vs. Battery Voltage Battery Voltage
Battery Current Arc Rate Arc Rate (V) (A) (mS) (Hz) 12.0 0.81 16 63
11.0 0.78 18 56 10.5 0.76 20.5 49 10.0 0.74 23.5 43 9.75 0.72 25 40
9.50 0.70 26 39 9.25 0.68 27 37 9.00 0.65 29 35 8.75 0.53 44 23
8.55 0.44 54 19
[0048] The converter is a half bridge, series loaded configuration.
This topology efficiently charges the output capacitor, C103. The
series inductor, L2, limits the charging current. The inductance
value and the switching frequency determine the rate of charging
current. A bridge driver controller integrated circuit, U1,
contains an oscillator and a pair of MOSFET drivers. R4 and C3 set
the switching frequency to 30 kHz. Q1 and Q2 are MOSFET switches
which drive the high voltage transformer, T1. The switches are
configured in series across the input source. They switch
alternately at a near 50% constant duty cycle. When Q1 switches on,
the input source delivers power to the transformer and charges
C5A-D. When Q2 switches on, C5A-D discharges to the transformer.
The transformer is thus driven alternately in both directions,
producing a 30 kHz AC output. The transformer has a step up ratio
of 290. The output of the transformer is rectified by high voltage
diodes configured in a bridge arrangement, which charges a 0.15
.mu.F 1600V capacitor, C103, to 1500 V. The primary voltage of the
T1 transformer is sensed and is set to trigger SCR, CR201 when the
voltage reaches 5.2V. A fast gate driver circuit provides a pulse
of current to the gate of the SCR causing a fast turn on. This
rapid turn on is necessary for a low loss energy transfer from
capacitor, C103, to the step-up (1:63) high voltage transformer.
This ratio will produce a pulse output of greater than 50 kV. The
electrodes are spaced to arc at a voltage below 50 kV.
[0049] FIG. 3B depicts the waveform generator circuit from
transformer T2 to the output electrodes E. The secondary output
leads of T2 are soldered to eight 390 pF, 3 kV capacitors
configured in series. The secondary leads are also soldered to the
output electrodes E, which deliver the final output waveform to a
subject. The amount of output capacitance determines the intensity
and duration of the arc. When the output capacitors discharge to a
low voltage, the arc extinguishes, the SCR resets to an off state,
allowing the charge cycle to repeat. The charge period is about 60
Hz for a fully charged battery.
[0050] Some existing stun devices utilize a spark gap as the switch
to drive the high voltage transformer; some such spark gaps are
rated to operate reliably for a minimum of 3,000,000 cycles. At 60
Hz, this would equate to less than 14 hours of continuous
operation. The SCR switch described herein may be more reliable
than the existing spark gap designs, even though there are more
components required to drive the SCR. Unlike the spark gap, the SCR
does not have a wear out mechanism and may operate for more than 10
years of continuous operation. Another advantage using the SCR is
the arc rate can be increased to greater than 100 Hz and maintain
thermal stability.
[0051] FIG. 3C depicts a bobbin 150 utilized in the circuit
depicted in FIG. 3B. This bobbin 150 is configured to maintain a
known minimum physical separation S between windings of transformer
wire 152, which is wrapped around the bobbin 150. This has the
effect of limiting the maximum voltage between any two adjacent
wires to a value less than that which may cause an electrical short
inside the transformer. This minimum physical separation S between
wires 152 combined with the use of a high dielectric encapsulating
polymer ensures a reliable high power output transformer.
[0052] FIGS. 4A-4I are plots of an output signal waveform of an
actual circuit manufactured in accordance with the schematic
depicted in FIGS. 3A-3B. FIG. 4A shows the amplitude of the output
voltage, and indicates a peak measurement of 19.8 kV (a 1000.times.
probe was used during measurement). FIG. 4B shows the frequency of
the output voltage; the time between pulses measures 15 ms, which
converts to a frequency of 66.7 Hz. FIG. 4C shows a more detailed
view of the voltage amplitude by concentrating on a single pulse,
again using a 1000.times. probe. The peak of the pulse measures
19.5 kV and, as in FIG. 4A, the full 50 kV output is not reflected
due to the arcing across the output terminals. FIG. 4D shows the
width of the voltage pulse, measuring 3.12 .mu.s. FIG. 4E shoes the
amplitude of the current. The maximum peak current measured was
6.13 amps. FIG. 4F shows the frequency of the output current. The
time between pulses measures 15 ms, which again converts to a
frequency of 66.7 Hz. FIG. 4G shows the amplitude of a single
current pulse, measuring 6.76 amps. FIG. 4H shows the rise time of
the current pulse, measuring 2.8 .mu.s. FIG. 4I shows the decay
time of the current pulse measuring 45.4 .mu.s. The waveform is
generally square in shape, but other pulsed or repeating waveforms,
such as sinusoidal, triangular, and/or sawtooth, are also
contemplated.
[0053] Testing has demonstrated that the application of waveforms
having certain characteristics to live mammals (e.g., mini-pigs)
produces muscular contraction and, in some cases, partial or
complete tetany without discernible detrimental short- or long-term
effects. A number of examples related to these findings follow.
Methods of testing the waveforms to achieve the desired muscular
response included some or all of the following procedures and
protocols.
EXAMPLE 1
Determination of Optimized Frequency to Achieve Tetany in a
Mammal
[0054] This experiment shows that the optimized frequency of a
waveform to produce tetany in a subject mammal is in a range from
about 50 Hz to about 70 Hz.
[0055] Voltage was maintained while the frequency of the waveform
was varied between 1 Hz-1000 Hz, and electromyogram (EMG) data from
the mammals was recorded for each stimulus frequency (i.e., 1, 2,
5, 10, 20, 50, 60, 70, 100, 200, 500, 1000 Hz). Stimulating needle
electrodes were placed on either side of a femoral nerve of a
subject approximately 1 cm apart, while recording electrodes were
placed about 8 cm apart, one on a knee and the other in a middle
part of the rectus femorus muscle. Recordings were taken from both
ipsi- and contralateral sides of the body. The stimulus pulse
amplitudes were maintained at 60 V for each frequency tested and
duration of the waveform pulse was 0.1 ms in all cases. The
waveforms tested comprised a generally square shape pulsed profile.
Recorded signals were amplified 2300.times. and were bandpass
filtered at 10 and 5000 Hz. Data were digitized and stored to a
hard disk at 10,000 samples/second for 5 seconds in all cases.
[0056] Time and frequency spectra were analyzed to determine the
waveform frequency corresponding to maximal muscle contraction.
Data means were subtracted from each sample to eliminate the DC
component. Time series of each stimulation frequency are plotted
and detail of the EMG waveform just following the stimulus pulse is
presented in FIGS. 5A-5C. Power spectra were calculated using the
discrete Fourier transform in MATLAB.
[0057] Application of the stimuli caused various responses in the
subjects, from no response to total muscular contraction (i.e.,
tetany). It was noted that, at low frequencies (less than about 40
Hz), the muscle was able to relax between applications of the
stimulus, thus tetany could not be achieved. At higher frequencies
(over about 80 Hz), muscles would contract, but were unable to
sustain tetany for a prolonged period of time.
[0058] The test data was analyzed to determine what waveform
characteristics resulted in muscle contraction, and time and
frequency spectra were analyzed to determine the frequency
corresponding to maximal muscle contraction. Time series of the
stimulation frequencies that achieved the greatest degree of
muscular contraction are presented in FIGS. 5A-5C.
[0059] In FIGS. 5A-5C, stimulus frequencies of 50 Hz (FIG. 5A), 60
Hz (FIG. 5B), and 70 Hz (FIG. 5C) are shown. At these frequencies,
EMG amplitudes are diminished after the second and subsequent
stimuli are applied. Visually, the leg to which the waveform was
applied remained tetanic during the entire 5 second signal
discharge, indicating maximal incapacitation. The time series was
shortened to show detail of the response that lasted about 5
seconds. The responses are inverted due to recording electrode
polarity. Stimuli are applied at time points corresponding to the
stimulus over the time series shown as sharp voltage transients.
EMG waveforms arise from the rectus femorus muscle shortly after
the stimulus is applied (about 5 ms). The response shows the muscle
does not have time to relax before subsequent stimuli are applied
and is in complete tetanic contraction for the duration of the
waveform application. This is shown by the EMG never settling at
baseline before the next stimulus. Also, the amplitude of each
response varies over the duration of the stun, but does not fall
below 3.5 mV. Any response above 2 mV indicates strong muscle
contraction. Thus, the testing procedures confirm that an optimized
EMI waveform with a frequency in a range of about 50 Hz to about 70
Hz achieves tetany in mammals.
EXAMPLE 2
EMI Produced by Waveform Generated by the Circuit of FIGS.
3A-3B
[0060] This example demonstrates that the waveform generated by the
circuit depicted in FIGS. 3A-3B produces EMI in a mammal.
[0061] Stimulating electrodes were fabricated out of 3 mm diameter
stainless steel. Care was taken in the design and fabrication
process to promote uniform charge distribution during stimulation.
Two planar and two hemispherical electrodes were fabricated. The
hemispherical electrodes were filed while turning in a drill press
until a ball shape was achieved. Layers of primer and enamel paint
were applied to all surfaces. The paint was allowed to cure at
about 40.degree. C. for 1 hour. To create the planar electrodes,
paint was removed from one end with 600 grit sandpaper and the
surface was polished with 4-0 emery paper until the surface was
shiny. Paint was removed and surfaces were polished on the
hemispherical electrodes in the same manner. An additional 2 mm of
paint was removed from the base of the hemisphere to expose more
surface area. The surface area of the planar electrodes was 0.071
cm.sup.2 and hemispherical electrode was 0.33 cm.sup.2.
[0062] Hemispherical electrodes were chosen for the experiment due
to their larger surface area and ease with which they could be
positioned. The subject mammal was anesthetized and the ulnar nerve
was dissected out of the left wrist. Connective tissue surrounding
the nerve was removed and electrodes were positioned under the
nerve. Electrodes were oriented parallel with the nerve such that
the current path runs from one electrode to another through the
nerve, assuming charges penetrate the nerve sheath. Tags made out
of surgical tape were used to hold the electrodes in place with
haemostatic forceps during stimulation. A Weitlaner was used to
hold the surrounding tissue open during stimulation. Care was taken
so that the electrodes or alligator clips did not touch the
surgical instruments.
[0063] The subject was grounded with five salt-bridge electrodes
distributed evenly along between the lower neck and hip along the
dorsal surface. The stratum corneum was removed with abrasive pads
before electrodes were applied. Leads were stripped, wound
together, and connected to earth ground. In this round of testing,
conductive electrodes 4 cm long and 0.3 cm in diameter were
connected to the electrode terminals of the circuit and placed at
various locations on the body of the subject. One electrode was
placed subcutaneously in the thorax just left of the midline, and
the other subcutaneously in the abdomen, just right of the midline.
The distance between the two electrodes was about 15 cm. The
waveform was generated and full body EMI was observed.
[0064] The frequency of the signal generated by the circuit (about
66.7 Hz) in accordance with that depicted in FIGS. 3A-3B falls
within the frequency range of the optimized signal, as noted with
regard to FIGS. 4B and 4F. It is noted that this frequency is
within the optimized frequency range determined in Example 1 and
EMI was achieved, as expected. Example 1, above, also indicates
that EMG waveforms arose from the stimulated muscle about 5 ms
after the stimulus was applied: Such a time delay may be adjusted
in a commercial embodiment of the stun device of the present
invention. Depending on the characteristics of the waveform, the
time period from application to EMI could be greater than or less
than about 5 ms. Variation of the time period above this 5 ms datum
should be balanced against the reaction time of a subject. A
commercial embodiment of the stun device of the present invention
could advantageously produce an EMI in a subject before the subject
could withdraw or recoil from the device.
EXAMPLE 3
Acute Study of Effects of a Waveform on Subject
[0065] The purpose of the experiment was to characterize the acute
effects of damped pulsed DC electric fields as produced by the
circuit of FIGS. 3A-3B on living tissue.
[0066] Several experiments were performed in vivo on mammals, using
the circuit in accordance with that depicted in FIGS. 3A-3B. An EMI
test device utilizing the circuit in accordance with that depicted
in FIGS. 3A-3B was used to deliver electrical signals to the
subjects comprising 0.15 .mu.F capacitance. The device was held in
a vertical orientation by clamping a 2'' PVC pipe to the stand and
was assembled such that the device was sheathed in the pipe to
permit a uniform downward force on the device resulting from a
total mass of 1.5 kg. A 12.0 VDC, 800 mA power supply was used as
the power source. The subjects were anesthetized during all
electrical discharges and all subsequent monitoring sessions.
[0067] Compound muscle action potential (CMAP) recordings were
obtained using EMG using pediatric Ag/AgCl surface electrodes as
sensing and reference electrodes. These electrodes were placed over
the middle of the muscle belly (recording electrode) and on the
common tendon (reference electrode) at the knee (8 cm distal to the
recording electrode). Stimulatory signals were delivered
cutaneously over the femoral nerve using gold plated electrodes
separated by 1 cm. The amplitude of the CMAP was maximized by
adjusting the position of the trigger electrodes and the amperage
of the stimulating current. The positions of the trigger
electrodes, reference, and sensing electrodes were marked using
indelible marker so that electrodes could be placed in the same
positions at each subsequent monitoring session. A grounding
electrode was placed nearby and the stimulation current used was 20
mA, which exceeded the amperage needed to achieve a maximal CMAP by
approximately 50%. Pumice alcohol pads were used to mildly abrade
the skin surface to reduce the impedance and electrode gel was
placed under each electrode. Four or five sequential stimulations
and recordings were performed at each time point and the measured
values averaged to yield the values reported in FIGS. 6A-6D, 7A-7D,
and 8A-8D. In these figures, the results depicted are averaged
values for each timed signal dosage. In addition, positive controls
(provided by defibrillator discharges, as noted below) are
identified by the designator "Avg Defib." Untreated (unstimulated)
controls are identified by the designator "Avg Control."
[0068] The electrodes were placed in contact with the subject's
skin and the waveform was applied for different durations to
confirm that damage to the subject is minimal or non-existent. Only
one discharge or set of discharges was administered at each dose.
Discharges for the acute study were administered in 5 second
increments followed by 5 second rests until the total amount of
discharge duration added up to the values shown in the figures
(i.e., 5, 10, 20, 40, 80, and 160 sec). During these discharges,
the respirator was allowed to continue delivering air to the
subject at the same rate as mentioned above. The acute (i.e.,
within 72 hours after administration) electrophysiological
responses and effects on nerve, skeletal muscle, and skin survival
and tissue morphology were assessed.
[0069] Positive control was provided by defibrillator discharges
over the ventral thigh. Each positive control subject was exposed
to four separate DC discharges over the ventral thigh from a
defibrillator set at 360 Joules. These discharges were delivered
with one paddle on the left lower abdomen and the other about 10 cm
therefrom on the left thigh just above the knee over the muscle and
tendons of the quadratus femoris muscle group. Each of these
discharges occurred at approximately 200-1500 VDC, 20-65 Amperes,
for 5-7 ms. A 2-inch layer of expanded polystyrene was placed under
the subject to isolate it electrically from the underlying
stainless steel table. As a result, the only current path present
was through the paddles of the defibrillator. Blood chemistry
samples were drawn at the times indicated and analyzed. The results
of these studies allow assessment of health effects of
cutaneously-applied DC current derived from the circuit on
physiology at several levels.
[0070] Specifically, FIGS. 6A-6C depict measured parameters of an
M-Wave generated by the various dosages of the electrical stimulus
generated by the circuit of FIGS. 3A-3B. These measurements were
taken in the limb to which the electrical stimulus was applied. The
M-wave is indicative of muscular contraction. FIG. 6D depicts the
F-Wave latency, again in the limb to which the stimulus is applied.
The F-Wave represents the time between the stimulation to the onset
of the impulse. FIGS. 7A-7D depict the same parameters as FIGS.
6A-6D, as measured in the non-shocked, contralateral leg.
[0071] FIG. 8A depicts lactic acid concentrations present in the
blood as a result of the EMI waveform application. Several
indications of a mild but significant respiratory or metabolic
acidosis were seen, but these conditions were transient, and
indicate that the lactic acid present in the subject remains
substantially unchanged, as compared to that parameter measured in
the untreated control. Some of these effects can probably be
attributed to additional stress associated with multiple, prolonged
(e.g., uninterrupted 40 second) discharges without ventilatory
support.
[0072] Related blood analytes reflecting acid-base balance were
observed and are within acceptable ranges, including pH and
pCO.sub.2.
[0073] The effects of the discharges on cardiac troponin I
concentrations are presented in FIG. 8B. The effects of the
discharges on myoglobin concentrations are presented in FIG. 8C.
The effects of the discharges on CK-MB concentrations are presented
in FIG. 8D. The results indicate that strong muscle responses are
possible with minimal damage attendant therewith, as the values of
each parameter are substantially unchanged relative to the
parameters measured from the control subjects. Discharges from the
circuit disclosed in FIGS. 3A-3B caused strong muscle contractions
primarily in extensor muscle groups. During the discharge, this
occurred initially near the discharge site and then moved to the
contralateral limb followed by the upper trunk and appendages. The
device discharges had either no effect or only minor effects on
blood chemistry values, tissue structure and viability local to the
discharge site, skeletal muscle function, and cardiac rhythm during
the 72 hour post-discharge time period. Any effects from the EMI
discharges seen on the physiological parameters studied were
relatively small and transient. This was the case even at high
discharge doses, i.e., after 40, 80, or even 160 second discharges
into the ventral thigh muscles or directly over the femoral nerve
at the inguinal ligament.
[0074] In sharp contrast to the effects of the EMI device,
defibrillator discharges had marked effects on skeletal muscle
function and on numerous blood chemistry values. They also caused
clear skeletal muscle and peripheral nerve damage and necrosis and
may also have caused some cardiac muscle injury. Myoglobin and
CK-MB were unaffected in EMI exposure groups, but strong elevations
in myoglobin were observed in the defibrillator group. This is
consistent with the severe skeletal muscle damage seen in this
group. Notably, no significant increases in troponin I were seen in
any of the mammals exposed to EMI discharges from the device
described herein. All of the EMG tests showed no significant
results, confirming the safety to nerve and muscle tissue. All
histological examinations of affected tissues revealed no damage as
discerned by histological preparations.
[0075] Recurring muscular contraction is accompanied by an increase
in lactic acid in the body. If too much lactic acid is generated,
and the body is unable to clear the acid, acidosis may occur. The
incidence of acidosis increases if a subject is already under
exertion or stress due, for example, to exercise, running,
fighting, substance ingestion, etc. Accordingly, muscular
contraction attendant with limited lactic acid production is
desirable in a stun device. Notably, as muscular incapacitation
approaches complete tetany, lactic acid production is reduced,
making the state of complete tetany substantially safer (from the
standpoint of lactic acid production), than incomplete muscle
contraction. The low levels of lactate observed were slightly above
normal but clearly indicate that lactate levels did not increase as
a function of EMI duration. This result is important, as many
circumstances of stun device use potentially involve persons with
pre-existing high lactate levels, due to exertion and/or drug
consumption and/or restraint due to police action.
[0076] A number of blood parameters were evaluated, including
plasma or serum myoglobin, troponin I, and CK-MB, all of which have
been shown to be useful in evaluating possible cardiac muscle
damage, usually due to myocardial infarction. Cardiac troponin I
has been shown to be the most specific marker for myocardial
damage, as this isoform of troponin is located only in the heart
and differs from troponin I found in skeletal muscle. Cardiac
troponin I levels in blood are usually almost undetectable, but
within 4-6 hours post-myocardial infarction, levels change
considerably and peak at 12-24 hours. These levels may remain
altered for several days.
[0077] Myoglobin and CK-MB concentrations can change from
non-cardiac related injuries. Serum myoglobin concentrations change
within 2-4 hours of myocardial injury, but this marker will also
typically change as a result of skeletal muscle damage. CK-MB is
found in cardiac and skeletal muscle but is present in much higher
amounts in cardiac muscle. CK-MB levels can change within 3-4 hours
of cardiac injury and remain so for 60-70 hours. A disadvantage of
using the CK-MB marker is that chronic muscle disease, skeletal
muscle trauma, and renal failure may also cause serum
concentrations to vary. As a result, it is desirable to evaluate
for troponin I, myoglobin, and CK-MB to determine the extent of
cardiac and skeletal muscle injury.
EXAMPLE 4
Long-Term Study of Effects of Waveform on Subject
[0078] The purpose of the experiment was to characterize the
long-term effects of pulsed DC electric fields as produced by the
circuit of FIGS. 3A-3B on living tissue.
[0079] The protocols utilized for Example 4 were essentially the
same as those utilized in Example 3, with the following exceptions.
A total of 21 subjects were stimulated for 40 second continuous
increments with the respirator turned off. At the end of each 40
second discharge, the respirator was turned on to allow 2 breaths
and then shut off again. This sequence was repeated twice for an 80
second discharge and 4 times for the 160 second discharge, after
the final discharge the respirator was restarted at the previous
rate. Since some effects of electrical discharge are delayed for
days or weeks after the initial exposure, the long-term (i.e., up
to 30 days after administration) effects on these parameters were
assessed.
[0080] The M-Wave and F-Wave characteristics measured in the acute
experiment, above, are depicted in FIGS. 9A-9D (for the shocked
leg) and 10A-10D (for the unshocked leg). Specifically, FIGS. 9A-9C
depict measured parameters of an M-Wave generated by the average 80
second dosage of the electrical stimulus and the untreated control
generated by the circuit of FIGS. 3A-3B. These measurements were
taken in the limb to which the electrical stimulus was applied. The
M-wave is indicative of muscular contraction. FIG. 9D depicts the
F-Wave latency, again in the limb to which the stimulus is applied.
The F-Wave represents the time between the stimulation to the onset
of the impulse. FIGS. 10A-10D depict the same parameters as FIGS.
9A-9D, as measured in the non-shocked, contralateral leg.
[0081] FIG. 11A also indicates that, long after application of the
waveform, the lactic acid production in the subject is limited, and
remains substantially unchanged relative to the untreated control.
As can be seen in FIGS. 11C-11D, the values indicate that no
significant changes in serum myoglobin, cardiac troponin I, and
serum CK-MB concentrations were present, indicating little or no
damage to the subjects observed. All of the parameters studied
returned to normal levels during the long-term experiment, or
remained unchanged from the parameters measured from the control
subjects, offering additional evidence of the safety of the EMI
device and waveform described herein. The untreated control is
designated in the FIGS. as "Avg Control." These results are similar
to those of the acute study, and are indicative of little or no
muscular damage in the subjects.
[0082] The invention has been described in detail in connection
with various embodiments. These embodiments, however, are merely
for example only and the invention is not limited thereto. It will
be appreciated by those skilled in the art that other variations
and modifications can be easily made within the scope of the
invention as defined by the appended claims.
* * * * *