U.S. patent application number 15/601386 was filed with the patent office on 2017-09-07 for novel biphasic or multiphasic pulse generator and method.
This patent application is currently assigned to Cardio Thrive, Inc.. The applicant listed for this patent is CardioThrive, Inc.. Invention is credited to Peter D. Gray, Douglas M. Raymond, Shelley J. Savage, Walter T. Savage.
Application Number | 20170252572 15/601386 |
Document ID | / |
Family ID | 56407032 |
Filed Date | 2017-09-07 |
United States Patent
Application |
20170252572 |
Kind Code |
A1 |
Raymond; Douglas M. ; et
al. |
September 7, 2017 |
NOVEL BIPHASIC OR MULTIPHASIC PULSE GENERATOR AND METHOD
Abstract
A dynamically adjustable biphasic or multiphasic pulse
generation system and method are provided. The dynamically
adjustable biphasic or multiphasic pulse generator system may be
used as a pulse generation system for a defibrillator or other type
of electrical stimulation medical device.
Inventors: |
Raymond; Douglas M.;
(Livermore, CA) ; Gray; Peter D.; (Vallejo,
CA) ; Savage; Walter T.; (Concord, CA) ;
Savage; Shelley J.; (Concord, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CardioThrive, Inc. |
Concord |
CA |
US |
|
|
Assignee: |
Cardio Thrive, Inc.
|
Family ID: |
56407032 |
Appl. No.: |
15/601386 |
Filed: |
May 22, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14661949 |
Mar 18, 2015 |
9656094 |
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15601386 |
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14303541 |
Jun 12, 2014 |
9616243 |
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14661949 |
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61835443 |
Jun 14, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61N 1/36146 20130101;
A61N 1/36128 20130101; A61N 1/3906 20130101; A61N 1/3912 20130101;
A61N 1/3975 20130101; A61N 1/3625 20130101; A61N 1/39 20130101 |
International
Class: |
A61N 1/39 20060101
A61N001/39; A61N 1/36 20060101 A61N001/36 |
Claims
1. A multiphasic pulse generator, comprising: a pulse waveform
generator that generates a pulse waveform having at least one first
phase of the pulse waveform and at least one second phase of the
pulse waveform, wherein the first phase has an amplitude whose
value is less than an amplitude of the second phase and wherein the
first phase has a polarity and the second phase has an opposite
polarity to the first phase; a power source; a first subsystem,
coupled to the power source to draw power from the power source,
that generates at least the first phase of the pulse waveform, the
subsystem having an energy reservoir and a high voltage switch; a
second subsystem, coupled to the power source to draw power from
the power source, that generates at least the second phase of the
pulse waveform, the second subsystem having a second energy
reservoir and a second high voltage switch; and a control logic
unit that includes the high voltage switch and the second high
voltage switch and controls the first and second subsystems to
generate the pulse waveform having the at least one first phase and
the at least one second phase.
2. The generator of claim 1, wherein the first subsystem further
comprises a high voltage generator and the energy reservoir of the
first subsystem further comprises one or more capacitors.
3. The generator of claim 2, wherein the second subsystem further
comprises a high voltage generator and the energy reservoir of the
second subsystem further comprises one or more capacitors.
4. The generator of claim 1, wherein the first subsystem further
comprises a high voltage generator and wherein the second subsystem
further comprises a high voltage generator.
5. The generator of claim 4, wherein the energy reservoir of the
first subsystem further comprises one or more capacitors and the
energy reservoir of the second subsystem further comprises one or
more capacitors.
6. The generator of claim 1, wherein the power source further
comprises a high voltage generator.
7. The generator of claim 6, wherein the energy reservoir of the
first subsystem further comprises one or more capacitors.
8. The generator of claim 7, wherein the energy reservoir of the
second subsystem further comprises one or more capacitors.
9. The generator of claim 1, wherein the generated pulse waveform
has a plurality of first phases and a plurality of second phases to
generate a multiphasic pulse waveform.
10. The generator of claim 1, wherein the generated pulse waveform
has a single first phase and a single second phase to generate a
biphasic pulse waveform.
11. The generator of claim 1, wherein the generated pulse waveform
has the first phase that has a positive polarity and the second
phase that has a negative polarity.
12. The generator of claim 1, wherein the generated pulse waveform
has the first phase that has a negative polarity and the second
phase that has a positive polarity.
13. The generator of claim 1, wherein the generated pulse waveform
has an energy of between 0.1 to 200 joules of energy delivered to a
patient during the first phase and second phase of the generated
pulse waveform and an inter-pulse period between the first and
second phases.
14. The generator of claim 13, wherein the energy of the generated
pulse waveform is delivered to the patient during a 2 ms to 20 ms
time period.
15. The generator of claim 1 further comprising an adjustment
component that adjusts a slope of at least one phase of the pulse
waveform or an amplitude of at least one phase of the pulse
waveform.
16. The generator of claim 15, wherein the adjustment component is
an array of capacitors wherein one or more capacitors are selected
to adjust a slope of at least one phase of the pulse waveform or an
amplitude of at least one phase of the pulse waveform.
17. The generator of claim 16, wherein the array of capacitors is
one of capacitors connected in series, capacitors connected in
parallel and capacitors connected in series and parallel.
18. The generator of claim 15, wherein the adjustment component is
an array of resistors wherein one or more resistors are selected to
adjust a slope of at least one phase of the pulse waveform or an
amplitude of at least one phase of the pulse waveform.
19. The generator of claim 1, wherein the power source is one of a
battery and a AC power source.
20. The generator of claim 1 further comprising an H-bridge circuit
that delivers the pulse waveform to a patient.
21. A method for generating a multiphasic pulse, comprising:
providing a power source; generating at least a first phase of a
pulse waveform using a first subsystem coupled to the power source
to draw power from the power source and having an energy reservoir
and a high voltage switch; generating at least a second phase of
the pulse waveform using a second subsystem coupled to the power
source to draw power from the power source, that generates at least
the second phase of the pulse waveform, the second subsystem and
having a second energy reservoir and a second high voltage switch;
controlling, using control logic including the high voltage switch
and the second high voltage switch, the first and second subsystems
to generate the pulse waveform having the at least one first phase
and the at least one second phase; and wherein the first phase has
an amplitude whose value is less than an amplitude of the second
phase and wherein the first phase has a polarity and the second
phase has an opposite polarity to the first phase.
22. The method of claim 21, wherein controlling the first and
second subsystems further comprises generating a plurality of first
phases and a plurality of second phases to generate a multiphasic
pulse waveform.
23. The method of claim 21, wherein controlling the first and
second subsystems further comprises generating a single first phase
and a single second phase to generate a biphasic pulse
waveform.
24. The method of claim 21, wherein the generated pulse waveform
has the first phase that has a positive polarity and the second
phase that has a negative polarity.
25. The method of claim 21, wherein the generated pulse waveform
has the first phase that has a negative polarity and the second
phase that has a positive polarity.
26. The method of claim 21, wherein the generated pulse waveform
has an energy of between 0.1 to 200 joules of energy delivered to a
patient during the first phase and second phase of the generated
pulse waveform and an inter-pulse period between the first and
second phases.
27. The method of claim 26, wherein the energy of the generated
pulse waveform is delivered to the patient during a 2 ms to 20 ms
time period.
28. The method of claim 21 further comprising adjusting a slope of
at least one phase of the pulse waveform or an amplitude of at
least one phase of the pulse waveform.
29. The method of claim 21 further comprising delivering the pulse
waveform to a patient using an H-bridge circuit.
Description
PRIORITY CLAIMS/RELATED APPLICATIONS
[0001] This application is a continuation and claims priority under
35 USC 120 to U.S. patent application Ser. No. 14/661,949 filed on
Mar. 18, 2015 that in turn is a continuation in part of and claims
priority under 35 USC 120 to U.S. patent application Ser. No.
14/303,541, filed on Jun. 12, 2014 and entitled "Dynamically
Adjustable Multiphasic Defibrillator Pulse System And Method" which
in turn claims priority under 35 USC 120 and claims the benefit
under 35 USC 119(e) to U.S. Provisional Patent Application Ser. No.
61/835,443 filed Jun. 14, 2013 and titled "Dynamically Adjustable
Multiphasic Defibrillator Pulse System and Method", the entirety of
all of which are incorporated herein by reference.
FIELD
[0002] The disclosure relates to medical devices and in particular
to devices and methods that generate and deliver therapeutic
treatment pulses used in medical devices, such as cardioverters and
defibrillators, neuro-stimulators, musculo-skeletal stimulators,
organ stimulators and nerve stimulators. More specifically the
disclosure relates to the generation by such medical devices of a
new and innovatively shaped biphasic or multiphasic pulse
waveform.
BACKGROUND
[0003] It is well known that a signal having a waveform may have a
therapeutic benefit when the signal is applied to a patient. For
example, the therapeutic benefit to a patient may be a treatment
that is provided to the patient. The therapeutic benefit or
therapeutic treatment may include stimulation of a part of the body
of the patient or treatment of a sudden cardiac arrest of the
patient. Existing systems that apply a signal with a waveform to
the patient often generate and apply a well-known signal waveform
and do not provide much, or any, adjustability or variability of
the signal waveform.
[0004] In the context of defibrillators or cardioverters, today's
manual defibrillators deliver either an older style Monophasic
Pulse (a single high energy single polarity pulse) or the now more
common Biphasic Pulse (consisting of an initial positive high
energy pulse followed by a smaller inverted negative pulse).
Today's implantable cardioverter defibrillators (ICDs), automated
external defibrillators (AEDs) and wearable cardioverter
defibrillators (WCDs) all deliver Biphasic Pulses with various
pulse phase lengths, high initial starting pulse amplitude and
various pulse slopes. Each manufacturer of a particular
defibrillator, for commercial reasons, has their own unique and
slightly different exact timing and shape of the biphasic pulse for
their devices' pulses, although they are all based off of the
standard biphasic waveform design. Multiple clinical studies over
the last couple of decades have indicated that use of these
variants of the biphasic waveform has greater therapeutic value
than the older monophasic waveform does to a patient requiring
defibrillation therapy and that these standard biphasic waveforms
are efficacious at appreciably lower levels of energy delivery than
the original monophasic waveforms, and with a higher rate of
resuscitation success on first shock delivery.
[0005] Thus, almost all of the current defibrillator products that
use a biphasic waveform pulse have a single high-energy reservoir,
which, while simple and convenient, results in severe limitation on
the range of viable pulse shapes that can be delivered.
Specifically, the second (or Negative) phase of the Biphasic
waveform is currently characterized by a lower amplitude starting
point than the first (or Positive) phase of the Biphasic waveform,
as shown in FIG. 4. This is due to the partial draining of the
high-energy reservoir during delivery of the initial Positive phase
and then, after inverting the polarity of the waveform so that the
Negative phase is able to be delivered, there is only the same
partially drained amount of energy remaining in the energy
reservoir. This lower amplitude starting point constrains and
causes the lower initial amplitude of the Negative phase of the
waveform. The typical exponential decay discharge is shown by the
Positive phase of the waveform shown in FIG. 4.
[0006] The standard biphasic pulse waveform has been in common
usage in manual defibrillators and in AEDs since the mid-1990s, and
still results in energy levels of anywhere from 120 to 200 joules
or more being delivered to the patient in order to be efficacious.
This results in a very high level of electrical current passing
through the patient for a short period of time which can lead to
skin and flesh damage in the form of burns at the site of the
electrode pads or paddles in addition to the possibility of damage
to organs deeper within the patient's body, including the heart
itself. The significant amounts of energy used for each shock and
the large number of shocks that these AED devices are designed to
be able to deliver over their lifespan, has also limited the
ability to further shrink the size of the devices.
[0007] WCDs generally need to deliver shocks of 150-200 joules in
order to be efficacious, and this creates a lower limit on the size
of the electrical components and the batteries required, and hence
impacts the overall size of the device and the comfort levels for
the patient wearing it.
[0008] ICDs, given that they are implanted within the body of
patients, have to be able to last for as many years as possible
before their batteries are exhausted and they have to be surgically
replaced with a new unit. Typically ICDs deliver biphasic shocks of
up to a maximum of 30-45 joules, lower than is needed for effective
external defibrillation as the devices are in direct contact with
the heart tissue of the patient. Subcutaneous ICDs, differ slightly
in that they are not in direct contact with the heart of the
patient, and these generally deliver biphasic shocks of 65-80
joules in order to be efficacious. Even at these lower energy
levels there is significant pain caused to the patient if a shock
is delivered in error by the device. Most existing devices are
designed to last for between 5-10 years before their batteries are
depleted and they need to be replaced.
[0009] Another, equally common type of defibrillator is the
Automated External Defibrillator (AED). Rather than being
implanted, the AED is an external device used by a third party to
resuscitate a person who has suffered from sudden cardiac arrest.
FIG. 9 illustrates a conventional AED 800, which includes a base
unit 802 and two pads 804. Sometimes paddles with handles are used
instead of the pads 804. The pads 804 are connected to the base
unit 802 using electrical cables 806.
[0010] A typical protocol for using the AED 800 is as follows.
Initially, the person who has suffered from sudden cardiac arrest
is placed on the floor. Clothing is removed to reveal the person's
chest 808. The pads 804 are applied to appropriate locations on the
chest 808, as illustrated in FIG. 9. The electrical system within
the base unit 802 generates a high voltage between the two pads
804, which delivers an electrical shock to the person. Ideally, the
shock restores a normal cardiac rhythm. In some cases, multiple
shocks are required.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 illustrates a medical device having a biphasic or
multiphasic waveform generator;
[0012] FIG. 2 illustrates a defibrillator medical device with a
multiphasic waveform generator with a plurality of independent
subsystems each with its own energy reservoir and energy
source;
[0013] FIG. 3 illustrates a defibrillator medical device with a
biphasic waveform generator with two independent subsystems each
with its own energy reservoir and energy source;
[0014] FIG. 4 illustrates a standard biphasic pulse waveform where
the second (negative) phase of the waveform is smaller in amplitude
than that of the first (positive) phase of the waveform;
[0015] FIGS. 5A, 5B and 5C illustrate different examples of a novel
biphasic or multiphasic pulse waveform generated by the biphasic or
multiphasic waveform generator where the second (negative) phase of
the waveform is larger in amplitude than the amplitude of the first
(positive) phase of the waveform;
[0016] FIG. 6 illustrates an embodiment of a biphasic/multiphasic
waveform generator with a single circuit containing multiple energy
reservoirs which can be dynamically charged separately from a
single energy source and then discharged through the H-bridge;
[0017] FIG. 7 illustrates a biphasic/multiphasic waveform generator
with a single circuit containing multiple energy reservoirs which
can be dynamically charged separately and then discharged through
an H-bridge;
[0018] FIG. 8 illustrates a circuit for adjusting the biphasic or
multiphasic waveform generator system's capacitance;
[0019] FIG. 9 diagrammatically illustrates an example of a
conventional external defibrillator; and
[0020] FIG. 10 illustrates a circuit for adjusting the waveform
generator system's resistance/impedance.
DETAILED DESCRIPTION OF ONE OR MORE EMBODIMENTS
[0021] The disclosure is applicable to various medical devices
including all defibrillator types: external (manual,
semi-automated, and fully automated), wearable, implantable and
subcutaneous implantable. In addition to defibrillators, the
medical device may also be cardioverters and external/internal
pacers, as well as other types of electrical stimulation medical
devices, such as: neuro-stimulators, musculo-skeletal stimulators,
organ stimulators and nerve/peripheral nerve stimulators, whether
the devices are external or implantable. The novel biphasic or
multiphasic waveform generator may be particularly useful for any
type of defibrillator and examples of the novel biphasic or
multiphasic waveform generator system will be described in the
context of a defibrillator for illustration purposes. It will be
appreciated, however, that the novel biphasic or multiphasic
waveform generator may generate and deliver a much wider range of
waveforms than has previously been possible in the art (or as shown
in the examples) including a new generation/family of novel
biphasic or multiphasic waveforms, as shown in FIG. 5A, FIG. 5B and
FIG. 5C. Thus, the novel biphasic or multiphasic waveform generator
has greater utility to existing devices since it may be used to
generate one or more of this family of novel lower energy biphasic
pulses. For example, the novel biphasic or multiphasic waveform
generator may be configured to generate and deliver a wide range of
the new low energy biphasic or multiphasic waveforms with varying
pulse timings, phase tilts and amplitudes. Such waveforms can be
used in the various medical devices described above. In these
devices the pulse generator system may be used to generate
therapeutic treatment pulses and then provide the pulses to a
patient using paddles or pads or other suitable forms of
electrodes.
[0022] The novel biphasic or multiphasic waveform generator can be
embodied in a number of different ways, constituting a range of
different potential circuit designs all of which are within the
scope of this disclosure since any of the circuit designs would be
able to generate and deliver a wide range of biphasic and/or
multiphasic waveforms including the new family/generation of low
energy biphasic and/or multiphasic waveforms where the first phase
of the waveform has a lower amplitude than the second phase of the
waveform.
[0023] FIG. 1 illustrates a medical device system 100 having a
novel biphasic or multiphasic waveform generator 104. As described
above, the medical device system may be any type of defibrillator
system or any of the other types of medical devices described
above. The medical device system 100 may include a medical device
102 that generates and delivers a novel biphasic or multiphasic
pulse waveform 110 to a patient 112. The novel biphasic or
multiphasic pulse waveform 110 may be a therapeutic pulse, a
defibrillation pulse and the like. As shown in FIG. 1, the medical
device 102 may include a novel multiphasic or biphasic waveform
generator 104, an energy source 106 and a control logic 108. The
novel multiphasic or biphasic waveform generator 104 may generate a
novel biphasic or multiphasic pulse waveform 110 using the energy
stored/generated by the energy source 106.
[0024] The novel biphasic or multiphasic pulse waveform 110 may
have one or more first phases and one or more second phases wherein
the first and second phases may be opposite polarities. In one
biphasic waveform example, the first phase may be a positive phase,
the second phase may be a negative phase and the second phase of
the waveform may be larger in amplitude than the amplitude of the
first phase of the waveform as shown in FIGS. 5A and 5B. Further,
as shown in FIG. 5C, a novel multiphasic pulse waveform that may be
generated by the multiphasic or biphasic waveform generator 104 is
shown in which the biphasic or multiphasic pulse waveform 110 has
more than one first phases and more than one second phases of the
pulse waveform. In the example in FIG. 5C, each first phase has a
positive polarity and each second phase has a negative polarity.
For example, the amplitude of the second phase may be less than
2500 volts and the first phase would be smaller than the second
phase. The multiphasic or biphasic waveform generator 104 may
deliver an energy of between 0.1 to 200 joules of energy to a
patient during the first phase and second phase of the generated
pulse waveform and an inter-pulse period between the first and
second phases. The multiphasic or biphasic waveform generator 104
may deliver the waveform to the patient during a 2 ms to 20 ms time
period.
[0025] The control logic unit 108 may be coupled to and/or
electrically connected to the multiphasic or biphasic waveform
generator 104 and the energy source 106 to control each of those
components to generate various version of the biphasic or
multiphasic pulse waveform 110. The energy source 106 may be one or
more power sources and one or more energy reservoirs. The control
logic unit 108 may be implemented in hardware. For example, the
control logic unit 108 may be a plurality of lines of computer code
that may be executed by a processor that is part of the medical
device. The plurality of lines of computer code may be executed by
the processor so that the processor is configured to control the
multiphasic or biphasic waveform generator 104 and the energy
source 106 to generate the biphasic or multiphasic pulse waveform
110. In another embodiment, the control logic unit 108 may be a
programmable logic device, application specific integrated circuit,
a state machine, a microcontroller that then controls the
multiphasic or biphasic waveform generator 104 and the energy
source 106 to generate the biphasic or multiphasic pulse waveform
110. The control logic unit may also include analog or digital
switching circuitry when the high voltage switching component 109
is part of the control logic unit 108.
[0026] As shown in FIG. 1, the biphasic or multiphasic pulse
waveform 110 may be delivered to the patient 112 using one or more
patient contact devices. The one or more patient contact devices
may be, for example, an electrode, a wire, a paddle, a pad or
anything else that is capable of delivering the biphasic or
multiphasic pulse waveform 110 to the patient 112. To further
illustrate a medical device that has the multiphasic or biphasic
waveform generator 104 and the energy source 106, an example of a
defibrillator that has the multiphasic or biphasic waveform
generator 104 and the energy source 106 is now described in further
detail.
[0027] FIG. 2 illustrates a defibrillator medical device 10 with a
multiphasic waveform generator with a plurality of independent
subsystems each with its own energy reservoir and energy source and
FIG. 3 illustrates a defibrillator medical device 10 with a
biphasic waveform generator with two independent subsystems each
with its own energy reservoir and energy source. In an embodiment
of the novel multiphasic or biphasic waveform generator 104 and the
energy source 106, the components may use two or more physically
and electrically distinct subsytems 12, 14 in which each subsystem
has the waveform generator 104, the energy source 106 and the
control logic 108 as shown in FIGS. 2-3. The reservoirs of stored
electrical energy may be in two or more different circuits (see
FIG. 2 and FIG. 3) that function together in a coordinated fashion
in order to generate and deliver the pulse waveform where each
phase of the waveform is produced from a separate reservoir of the
stored energy. The reservoirs of energy may be of the same
size/quantity or else of widely different sizes and may be supplied
by one or more energy sources.
[0028] The energy source 106 is not limited to any particular
number of energy reservoirs (such as capacitors) or energy sources
(such as batteries). Thus, the medical device system 10 may have a
plurality or "n" number (as many as wanted) of subsystems 12, 14
that together can be utilized to generate the various multiphasic
or biphasic waveforms. In the example embodiments shown in FIG. 2
and FIG. 3, there may be two sides, such as side A and side B as
shown, and each side may have one or more of the subsystems 12, 14
and each subsystem may generate a phase of the pulse waveform to
generate the biphasic or multiphasic waveform with one or more
first phases and one or more second phases. The two or more
subsystems 12, 14 permit the system to shape the various
characteristics of first and second phases separately from each
other. For example, in one example, the first phase may have a
positive polarity and its characteristics may be shaped
independently of the second phase that may have a negative polarity
and its characteristics. The above described functions may be
accomplished through the use of a fast switching
high-energy/voltage switch system as described below. The fast
switching high-energy/voltage switch system 109 may be part of the
control logic unit 108 or the generator 104.
[0029] Each subsystem 12, 14 of each side, as shown in FIG. 2 and
FIG. 3, may have the control logic and heart rhythm sense component
108 (that is connected to a similar component on the other side by
a digital control link 30 as shown in FIG. 2 and FIG. 3) that may
be also coupled to a high voltage switching system component 109.
The high voltage switching system component 109 may be implemented
using either analog circuits or digital circuits or even some
hybrid of the two approaches. Furthermore, the high voltage
switching system component 109 may be implemented through the use
of mechanical or solid-state switches or a combination of the two.
The energy reservoir may also be coupled, by a high voltage return
line 32 to the other side of the system as shown in FIG. 2 and FIG.
3. The high voltage return 32 electrically completes the circuit
and is present in existing defibrillators, but in a slightly
different form since in the existing style of devices it is split
into two parts in the form of the two leads which go from the main
defibrillator device to the internal or external surface of the
patient.
[0030] FIGS. 5A-5C illustrate examples of the biphasic or
multiphasic waveforms that may be generated by the systems shown in
FIGS. 2-3 as well as the systems shown in FIGS. 6-8. In the
examples in FIGS. 5A-5B a first phase may be a positive polarity
and the second phase may be a negative polarity. However, the
biphasic or multiphasic waveforms also may have a negative polarity
first pulse and a positive polarity second pulse. As shown in FIGS.
5A and 5B, the first phase pulse amplitude may be smaller than the
second phase amplitude. FIG. 5C illustrates a multiphasic waveform
in which the waveform has two or more positive polarity phases and
two or more negative polarity phases.
[0031] In another embodiment (see FIG. 6) the system 10 makes use
of two or more reservoirs of stored electrical energy 501 (such as
high voltage generator and reservoir 1061, high voltage generator
and reservoir 1062 and high voltage generator and reservoir 106n)
that are either statically or dynamically allocated from within a
single circuit 502 and that function together in a coordinated
fashion in order to generate and deliver the final waveform where
each phase of the waveform is produced from a separate reservoir of
the stored energy. The reservoirs of energy 501 may be of the same
size/quantity or else of widely different sizes and may be supplied
by one or more energy sources. The system 10 may also have the high
voltage switch 109 for each reservoir 501 and an H-bridge switch
110 that may be part of the control logic unit 108 or the generator
104. The H-bridge circuit is a known electronic circuit that
enables a voltage to be applied across a load, M, in either
direction using one or more switches (see
http://cp.literature.agilent.com/litweb/pdf/5989-6288EN.pdf that is
incorporated by reference herein for additional details about the
H-bridge circuit.)
[0032] In another embodiment (see FIG. 7) the system makes use of
at least one reservoir of stored electrical energy 601 in a
configuration that is divided up and either statically or
dynamically allocated into two or more portions of stored energy
602 from within a single circuit and that generates and delivers
the final waveform in a coordinated fashion where each phase of the
waveform is produced from a separate portion of the stored energy.
The portions of energy 602 may be of the same size/quantity or else
of widely different sizes and may be supplied by the one or more
energy sources. Essentially, this involves charging one or more
group(s)/array(s) of capacitors (the number of capacitors in a
statically or dynamically created group is based on the voltage and
energy requirements for the phase of the waveform or waveform that
is to be generated and delivered) and then discharging a select
number of capacitors in a group that is configured as required to
provide the desired waveform or phase of a waveform. The charging
and discharging of capacitors in parallel and in series is well
known in the art. Through a configuration of switches (mechanical
or solid state) one can disconnect a certain number of capacitors
from the original group/array of capacitors, thus separating the
stored energy into two (or more) portions/reservoirs that feed an
H-bridge switch 110, allowing the creation of a wide range of
waveform phases with different amplitudes, shapes and timings.
[0033] Another embodiment of the system makes use of a direct
current generation source in order to generate the initial phase of
the waveform and then uses one or more reservoirs of stored
electrical energy in order to generate the second phase of the
waveform and any additional phases of the waveform. The energy
reservoirs used may be supplied by one or more energy sources.
[0034] Another embodiment of the system makes use of a direct
current generation source in order to generate the initial phase of
the waveform and then uses one or more additional direct current
generation sources, configured alone, together, or else in
combination with reservoirs of stored electrical energy, in order
to generate the second phase of the waveform and any additional
phases of the waveform. The energy reservoirs used may be supplied
by one or more energy sources.
[0035] In additional embodiments, the pulse generator may be
configured with the circuitry, processors, programming and other
control mechanisms necessary to separately and individually vary
the phase timings, the inter-phase pulse timing(s), the phase tilts
and the phase amplitudes necessary to customize and optimize the
waveform for the patient at hand and for the specific therapeutic
purpose for which the waveform is being used.
[0036] The above described functions may be accomplished through
the use of a fast switching high-energy/voltage switch system 109
which can be either analog or digital in nature or even some hybrid
of the two approaches as shown in FIG. 2 and FIG. 3. The switching
can be accomplished through the use of mechanical or solid-state
switches or a combination of the two.
[0037] Other embodiments of the system discharge part of the
waveform's initial phase energy through the use of a statically or
dynamically allocated group of resistive power splitters (see FIG.
10), which steps the waveform's initial phase amplitude down across
the group of resistors, and in this manner delivers a smaller
remaining amplitude of the waveform's initial phase to the patient,
while still delivering a full amplitude of the second phase (and
any additional phases) to the patient.
[0038] Many embodiments of the system can make use of one or more
additional circuitry modules or subsystems intended to alter the RC
constant of the pulse delivery circuitry for one or more of the
pulse phases, and hence alter the tilt of the phase of the pulse
waveform involved. These modules or subsystems can consist of an
array of capacitors or an array of resistors, or of a combination
of the two (see FIG. 8 and FIG. 10).
[0039] In some embodiments of the system, the system may provide
for the recharging of individual energy reservoirs by the energy
sources during times (including inter-phase pulse times) that an
individual energy reservoir is not selected for discharge. This
provides the opportunity to interlace equivalent amplitude initial
multiphasic pulses utilizing several different high energy
reservoirs.
[0040] While the foregoing has been with reference to a particular
embodiment of the disclosure, it will be appreciated by those
skilled in the art that changes in this embodiment may be made
without departing from the principles and spirit of the disclosure,
the scope of which is defined by the appended claims.
* * * * *
References