Automated External Defibrillator

Abstract

An automated external defibrillator (AED) is described. The AED comprises two pads for placement on a patient, each pad including an energy storage system. The energy storage system includes at least two energy storage blocks, a switching circuit and a shock generation circuit connected to the two pads, and a controller connected to the switching circuit and the shock generation circuit. The controller is configured to perform electrical switching operations to provide defibrillation shocks in the two phases such that the voltage and peak current in each of the two phases are substantially the same. Each energy storage block includes at least one or more capacitors. In some embodiments, at least one of the energy storage blocks includes two or more capacitors connected in series, and at least two energy storage blocks are connected in parallel such that the capacitor system includes capacitors connected both in series and in parallel with each other.

Description

[Technical field]

[0001] The present invention is directed to an automatic external defibrillator having a small form factor that is still capable of delivering defibrillation shocks in two phases such that the voltage and peak current in each of the two phases are substantially the same.

[0002] The present invention further relates to an automatic external defibrillator having an energy storage system that includes capacitors connected in both series and parallel. [Background technology]

[0003] Automated external defibrillators (AEDs) automatically diagnose the presence of shockable arrhythmias and deliver an electric shock to restore normal heart rhythm.

[0004] Most AEDs available on the market are bulky devices typically stored in wall cabinets and are expensive. These AEDs have large form factors to accommodate the electrical components required to operate the AED to deliver a large voltage charge in a fraction of a second. In most cases, such AEDs are few in number and difficult to quickly locate and use in an emergency. Thus, AEDs remain unavailable to victims or bystanders in the vast majority of cases of sudden cardiac arrest.

[0005] Conversely, an implantable cardioverter-defibrillator (ICD) is a small, battery-powered device placed in the chest to detect and stop irregular heartbeats (arrhythmias). ICDs continuously monitor the heartbeat and deliver an electric shock if necessary to restore a regular heart rhythm. Because ICDs connect directly to the heart, compared to the resistance provided by the skin and tissues over the heart when using an AED, ICDs deliver a lower voltage to the heart compared to AEDs.

[0006] It is an object of the present disclosure to provide an improved energy storage system and artificial external defibrillator having the same that addresses or ameliorates one or more shortcomings or limitations associated with the prior art, or at least provides the public with a useful option. Summary of the Invention

[0007] In a first aspect, the present disclosure provides an automated external defibrillator (AED), comprising: two pads for placement on a patient, each pad including an energy storage system, the energy storage system including at least two energy storage blocks; a switching circuit and a shock generating circuit connected to the two pads; An automated external defibrillator (AED) may be provided that includes: a controller connected to the switching circuit and the shock generation circuit, the controller configured to perform electrical switching operations to provide defibrillation shocks in the two phases such that the voltage and peak current in each of the two phases are substantially the same.

[0008] In another aspect, the present disclosure may provide a method of operating an AED having two pads for placement on a patient, the method comprising: performing the functions of electrical measurement and stimulation of the patient's heart; Operate the controller to perform electrical switching operations to provide a defibrillation shock in two phases, the voltage and peak current in each of the two phases being substantially the same.

[0009] In another aspect, the present disclosure provides a defibrillator comprising: Two pads for placement on the patient; a capacitor system having at least two energy storage blocks, each energy storage block including a capacitor, the at least two energy storage blocks being connected in parallel; a switching circuit and a shock generating circuit connected to the two pads; A defibrillator may be provided that includes a controller connected to the switching circuit and the shock generation circuit, the controller configured to perform electrical switching operations to provide defibrillation shocks in the two phases such that the voltage and peak current in each of the two phases are substantially the same.

[0010] In another aspect, the disclosure may provide a defibrillator including a capacitor system having at least two energy storage blocks, each energy storage block including a capacitor, at least one of the energy storage blocks including two or more capacitors connected in series, and the at least two energy storage blocks connected in parallel such that the capacitor system includes capacitors connected both in series and in parallel with each other, and the series and parallel arrangements of the capacitors of the capacitor system are the same both during charging of the capacitor system and during discharging of the energy system to provide a defibrillation shock.

[0011] In another aspect, the present disclosure provides a defibrillator including a capacitor system having a plurality of energy storage blocks secured in parallel with one another, each energy storage block including a capacitor, and at least one of the energy storage blocks including two or more capacitors secured in series.

[0012] In another aspect, the disclosure provides a defibrillator including an energy storage system having at least two energy storage blocks electrically connected in parallel, each of the energy storage blocks including a capacitor, at least one of the energy storage blocks including two or more capacitors electrically connected in series such that the energy storage system includes capacitors arranged in both series and parallel, and the series and parallel arrangements of the capacitors of the energy storage system are the same both during charging of the energy system and during discharging of the energy system to provide a defibrillation shock.

[0013] In another aspect, the present disclosure provides a defibrillator including an energy storage system having at least two capacitor blocks electrically connected in parallel, at least one of the capacitor blocks including two or more capacitors electrically connected in series, and wherein the series and parallel arrangements of the capacitors of the energy storage system are the same both during charging of the energy system and during discharging of the energy system to provide a defibrillation shock.

[0014] In another aspect, the present disclosure provides an energy storage system for a defibrillator, the energy storage system being associated with a battery for charging the energy storage system and a pair of electrode pads capable of delivering stored energy as a defibrillation shock, the energy storage system including a plurality of energy storage blocks connected together in parallel, each energy storage block including a plurality of capacitors connected together in series.

[0015] In another aspect, the present disclosure provides a charge storage assembly for an automatic external defibrillator, the charge storage assembly comprising: A plurality of charge storage blocks fixedly connected in parallel; Each charge storage block includes a number of capacitors fixedly connected in series.

[0016] In another aspect, the present disclosure provides an artificial external defibrillator having a first bank and a second bank of capacitors, at least one bank including at least three capacitors, at least one capacitor connected in series to another of the capacitors and at least one capacitor connected in parallel to another of the capacitors, and the series and parallel arrangements of the capacitors are fixed.

[0017] In another aspect, the present disclosure provides a method of operating an automated external defibrillator, the method comprising: charging the capacitor system from a battery, the capacitor system including a first capacitor bank and a second capacitor bank each including at least three capacitors, at least one capacitor of each capacitor bank being connected in series with another one of the capacitors of the same capacitor bank, and at least one capacitor of each capacitor bank being connected in parallel with at least another one of the capacitors of the same capacitor bank; discharging a first capacitor bank to provide a first defibrillation phase; discharging the second capacitor bank to provide a second defibrillation phase; The series and parallel arrangement of the capacitors of the first and second capacitor banks is the same for both the charging and discharging steps.

[0018] In another aspect, the present disclosure provides a method of charging an automated external defibrillator, the method comprising: The method includes a step of charging a capacitor system from a battery, the capacitor system including at least two capacitors fixedly connected in series and at least one capacitor fixedly connected in parallel to the at least two capacitors fixedly connected in series.

[0019] In another aspect, the present disclosure provides a method of manufacturing a capacitor system for an automatic external defibrillator, the method comprising: Fixedly connecting a plurality of capacitors in series to form an energy storage block; providing a plurality of said energy storage blocks; and fixedly connecting a plurality of energy storage blocks together in parallel to form a capacitor system.

[0020] In another aspect, the present disclosure provides a defibrillator including a plurality of capacitors for storing energy for defibrillation, the capacitors being cylindrical and having longitudinal axes, the capacitors being disposed within the defibrillator such that the longitudinal axes of each capacitor lie in a common plane.

[0021] The following configurations may be relevant to any of the above aspects.

[0022] In one configuration, the at least two energy storage blocks are independent of each other for each of the two phases of the defibrillation shock.

[0023] In one configuration, at least two energy storage blocks are connected in parallel, each energy storage block including at least one capacitor, and at least one of the energy storage blocks includes two or more capacitors in series.

[0024] In one configuration, the series and parallel arrangement of the capacitors is the same both during charging of the energy storage block and during discharging of the energy storage block to provide a defibrillation shock.

[0025] In one configuration, each pad is approximately 100 cm 3 ~200cm 3 and a volume of about 50 cm 2 ~100cm 2 and a suitable range may be selected between any of these values.

[0026] In one configuration, the controller is further configured to generate equal leading edge waveforms for each of the two phases.

[0027] In one configuration, the controller is further configured to generate a dose of current for a defibrillation shock at a dose of power.

[0028] In one configuration, the controller is further configured to maintain a peak current in each phase such that a polarizing effect is observed in a first phase and a depolarizing effect is achieved in a second phase.

[0029] In one configuration, the controller is further configured to generate a full gradient waveform for each of the two phases.

[0030] In one configuration, the switching circuitry is configured to perform electrical switching operations such that one of the energy storage blocks is configured to charge, store, and discharge to provide energy to one of two phases, and the other of the energy storage blocks is configured to charge, store, and discharge to provide energy to the other of the two phases of a defibrillation shock.

[0031] In one configuration, the switching circuitry is configured to perform electrical switching operations such that the direction of current flow is maintained between each of the two phases during a defibrillation shock.

[0032] In one configuration, each of the capacitors of at least one of the energy storage blocks has the same or substantially the same nominal capacitance and operating voltage.

[0033] In one configuration, each energy storage block further includes one or more of a balancing resistor, a diode, or an operational amplifier connected in series and / or parallel connection with the at least one capacitor in each of the energy storage blocks.

[0034] In one configuration, the AED further comprises any one or more of a transformer, an electrical switch, a battery, and an inductor, each of the transformer, the electrical switch, the battery, and the inductor configured to be operable in a low voltage mode or a low power mode.

[0035] In one configuration, the shock generation circuit includes a charging circuit and / or a discharging circuit configured to charge and / or discharge one or more capacitors of the energy storage block.

[0036] In one configuration, the controller is configured to operate the shock generation circuitry and the switching circuitry to automatically perform the electrical measurement and stimulation of the patient's heart switching between two phases.

[0037] In one configuration, each of the two pads includes one or more electrodes, and at least one electrode of each pad is configured to perform at least one of electrical measurement and stimulation of the patient's heart.

[0038] In one configuration, the peak current and voltage in a first of the two phases of the defibrillation shock is maintained until a first time interval tp1 during which the polarization effect is observed in the patient.

[0039] In one configuration, the first time interval is the time it takes for a defibrillation shock to reach all cells of the patient's myocardium.

[0040] In one configuration, the multiple functions of electrical measurement and stimulation of a patient's heart performed by one or more electrodes in multiple directions include: measuring cardiac electrical signals to detect the positions of the two pads; measuring an ECG signal to detect a shockable cardiac rhythm; and if a shockable cardiac rhythm is detected, delivering, with the two pads, a defibrillation shock with a dosage based on the detected location of the pads.

[0041] In one configuration, the measured cardiac electrical signals used to detect the position of the two pads include voltage, current, impedance, or any combination thereof.

[0042] In one configuration, the capacitors of each energy storage block are fixed in series.

[0043] In one configuration, the series and parallel arrangements of the capacitors in the energy storage system are non-switchable.

[0044] In one configuration, the electrical connections between the capacitors of the capacitor system are not switched.

[0045] In one configuration, the capacitors of the energy storage system have a fixed, unswitched connection between them.

[0046] In one configuration, each of the energy storage blocks has at least two capacitors connected in series.

[0047] In one configuration, each of the energy storage blocks has a number of equal capacitors connected in series.

[0048] In one configuration, the first capacitor bank and the second capacitor bank each have the same total operating voltage.

[0049] In one configuration, each of the capacitors of at least one of the energy storage blocks has the same or substantially the same nominal capacitance and operating voltage.

[0050] In one configuration, each of the capacitors in each of the energy storage blocks has the same, or substantially the same, nominal capacitance and operating voltage.

[0051] In one configuration, each of the capacitors in at least one of the energy storage blocks are identical.

[0052] In one configuration, each of the capacitors in each of the energy storage blocks are identical.

[0053] In one configuration, each energy storage block includes a balancing resistor connected in parallel with the capacitor or capacitors of each respective energy storage block.

[0054] In one configuration, the balancing resistors are configured to maintain a uniform voltage across each capacitor of each respective energy storage block.

[0055] In one configuration, the capacitors of the capacitor system are cylindrical and have longitudinal axes, and the capacitors are arranged such that each of the longitudinal axes lies in a plane.

[0056] In one configuration, the capacitors of the capacitor system are cylindrical and have a longitudinal axis, and the capacitors are arranged such that the longitudinal axis of each capacitor is a) parallel or b) coaxial with the longitudinal axis of another capacitor.

[0057] In one configuration, the capacitor system includes a first capacitor bank and a second capacitor bank, each capacitor bank including at least two energy storage blocks, and at least one of the energy storage blocks of each capacitor bank includes two or more capacitors connected in series.

[0058] In one configuration, the first and second capacitor banks are configured to store and discharge charge, respectively, to provide energy for the first and second phases of a biphasic defibrillation shock.

[0059] In one configuration, the defibrillator includes four discharge switches, one between each of the first and second capacitor banks.

[0060] In one configuration, a first capacitor bank provides charge for a first phase of a biphasic defibrillation shock and a second capacitor bank provides charge for a second phase of the biphasic defibrillation shock.

[0061] In one configuration, no charge is transferred between the first and second capacitor banks.

[0062] In one configuration, the first capacitor bank and the second capacitor bank have different total capacitances.

[0063] In one configuration, the first capacitor bank again has approximately half the total capacitance of the second capacitor bank.

[0064] In one configuration, the first capacitor bank includes a greater number of energy storage blocks than the second capacitor bank.

[0065] In one configuration, each of the energy storage blocks includes four capacitors connected in series.

[0066] In one configuration, the second capacitor bank comprises four energy storage blocks connected in parallel.

[0067] In one configuration, each of the energy storage blocks includes four capacitors connected in series.

[0068] In one configuration, the capacitors in the energy storage block have a nominal capacitance of approximately 6.8 μF.

[0069] In one configuration, the capacitors of each energy storage block of one or both of the first and second capacitor banks have a nominal capacitance of approximately 6.8 μF.

[0070] In one configuration, each capacitor of each energy storage block of one or both of the first capacitor bank and the second capacitor bank has a nominal capacitance of approximately 6.8 μF.

[0071] In one configuration, the capacitors in the energy storage block have an operating voltage of approximately 450V.

[0072] In one configuration, the capacitors of each energy storage block of one or both of the first and second capacitor banks have an operating voltage of approximately 450V.

[0073] In one configuration, each capacitor of each energy storage block of one or both of the first capacitor bank and the second capacitor bank has an operating voltage of approximately 450V.

[0074] In one configuration, the defibrillator further comprises a battery for charging the capacitor system and a pair of electrode pads for delivering the stored energy as a defibrillation shock to the patient.

[0075] In one configuration, the defibrillator further comprises a charging circuit configured to charge the capacitor system from a battery.

[0076] In one configuration, the third capacitor is connected in parallel with both the first capacitor and the second capacitor.

[0077] In one configuration, each of the capacitors of at least one of the energy storage blocks has the same or substantially the same nominal capacitance and operating voltage.

[0078] In one configuration, the multiple charge storage blocks are arranged in a first charge storage bank and a second charge storage bank, the banks being for separated sequential discharge.

[0079] In one configuration, during each of the discharging steps, the capacitors of the first capacitor bank and the second capacitor bank are electrically isolated from each other.

[0080] In one configuration, the number of capacitors in each energy storage block is selected based on the operating voltage of the capacitors and the desired operating voltage of the capacitor system.

[0081] In one configuration, the number of energy storage blocks is selected based on the nominal capacitance of the capacitors and the desired total nominal capacitance of the capacitor system.

[0082] In one configuration, at least some of the capacitors are aligned axially parallel to one or more of the other ones of the capacitors.

[0083] In one configuration, each of the capacitors is aligned axially parallel to one or more of the other capacitors.

[0084] As used herein, the term "axis" refers to an axis of rotation about which a line or plane can be rotated to form a symmetrical shape. For example, a line rotated about an axis of rotation forms a surface, and a plane rotated about an axis of rotation forms a solid.

[0085] As used herein, the term "and / or" means "and" or "or," or both.

[0086] As used herein, "(s)" following a noun refers to the plural and / or the singular form of the noun.

[0087] For purposes of this specification, when method steps are listed in a sequence, the sequence does not necessarily imply that the steps are chronologically ordered in that sequence, unless there is another logical way to interpret the sequence.

[0088] The term "comprising" as used in this specification and the claims means "consisting at least in part of." When interpreting each statement in this specification that contains the term "comprising," there may be other features present than the feature preceded by that term. The related terms "comprise" and "comprises" should be interpreted in the same manner.

[0089] The invention may also be broadly described as consisting in any or all combinations of the parts, elements and features, and any two or more of the parts, elements or features, either individually or collectively, referred to or indicated in the specification of this application, and where a specific integer having a known equivalent in the art to which the invention pertains is referred to herein, such known equivalent is deemed to be incorporated herein as if individually set forth.

[0090] Numerous modifications of the structure and widely different embodiments and applications of the present invention will be suggested to those skilled in the art to which the present invention pertains without departing from the scope of the invention, which is defined in the appended claims. The disclosures and descriptions herein are purely illustrative and are not intended to be in any sense limiting.

[0091] Other aspects of the invention will become apparent from the following description, given by way of example only and referring to the accompanying drawings, in which: [Brief description of the drawings]

[0092] Preferred embodiments of the present invention will now be described, by way of example only, with reference to the drawings in which: [Figure 1] FIG. 1 is a circuit diagram of a capacitor system or portion thereof for a defibrillator showing two energy storage blocks of the capacitor system. [Diagram 2] FIG. 1 is a simplified circuit diagram of a defibrillator with a capacitor storage system. [Diagram 3] FIG. 1 is a circuit diagram of a capacitor storage system or a portion thereof. [Figure 4] FIG. 1 is a partial view of a simplified circuit diagram of a defibrillator with a capacitor storage system. [Diagram 5] FIG. 1 is a simplified circuit diagram of a defibrillator with a capacitor storage system having two banks of capacitors. [Figure 6A] FIG. 1 is a circuit diagram of a capacitor bank of a capacitor system for a defibrillator. [Figure 6B] FIG. 9B is a diagram of the circuit diagram of FIG. 9A showing the capacitor bank energy storage block. [Figure 7] FIG. 2 is a partial view of a simplified circuit diagram of a defibrillator with a capacitor storage system having two banks of capacitors. [Figure 8] FIG. 2 is a partial view of a simplified circuit diagram of a defibrillator with a capacitor system having two banks of capacitors. [Figure 9A] FIG. 1 is a diagram of a defibrillator or a portion of a defibrillator showing the internal components. [Figure 9B] FIG. 1 is a diagram of a defibrillator or a portion of a defibrillator showing various internal components. [Figure 10A] FIG. 2 is another view of the defibrillator or a portion of the defibrillator showing various internal components. [Figure 10B] FIG. 2 is another view of the defibrillator or a portion of the defibrillator showing various internal components. [Figure 10C] FIG. 2 is another view of the defibrillator or a portion of the defibrillator showing various internal components. [Figure 11] FIG. 1 is a diagram of a defibrillator mounted on a patient's torso. [Figure 12] FIG. 1 is a diagram of a defibrillator. [Figure 13A] FIG. 1 is a schematic diagram showing the placement of a capacitor system in a defibrillator. [Figure 13B] FIG. 1 is a schematic diagram showing the placement of a capacitor system in a defibrillator. [Figure 13C] FIG. 1 is a schematic diagram showing the placement of a capacitor system in a defibrillator. [Figure 14]FIG. 13 illustrates an exemplary embodiment of the capacitor configurations for each energy storage bank. [Figure 15] 1 is a graph of overall peak-to-peak current of different AEDs compared to current AEDs as described. [Figure 16] FIG. 2 is an alternative simplified circuit diagram of a defibrillator. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0093] An automated external defibrillator (AED) is described. The AED comprises two pads for placement on a patient, each pad including an energy storage system. The energy storage system includes at least two energy storage blocks, a switching circuit and a shock generation circuit connected to the two pads, and a controller connected to the switching circuit and the shock generation circuit. The controller is configured to perform electrical switching operations to provide defibrillation shocks in the two phases such that the voltage and peak current in each of the two phases are substantially the same. Each energy storage block includes at least one or more capacitors. In some embodiments, at least one of the energy storage blocks includes two or more capacitors connected in series, and at least two energy storage blocks are connected in parallel such that the capacitor system includes capacitors connected both in series and in parallel with each other.

[0094] The inventors have developed an AED with a reduced form factor that has a miniaturized yet effective waveform. Thus, the AED as described has a compact form factor with a low pad footprint relative to the component layout and packaging. At the same time, the pads are able to acquire ECG signals with high quality and deliver defibrillation shocks with high efficacy.

[0095] Thus, the inventors have created and described small form factor AEDs and capacitor configurations within AEDs that provide optimal and / or efficient solutions for generating waveforms within the size constraints and limitations of current capacitor technology and regulatory standards.

[0096] The above-mentioned AED has the following features: a) Low-energy defibrillation, or b) Equal leading edge waveforms, or c) A full gradient waveform, or d) Separate capacitor banks for each phase, or e) Small form factor, or f) Any combination of two or more of (a) to (e).

[0097] An AED (referred to herein as a defibrillator) as shown in Fig. 12 according to an embodiment of the present disclosure may generally include two defibrillation pads 11 and 12. Pads 11 and 12 may be initially joined together, but may also be separable from one another, and may be placed on a patient in, for example, an adult front-to-front position as shown in Fig. 11.

[0098] The AED 10 may have a compact device form factor with a small pad footprint. The two pads 11 and 12 of the AED are configured to perform multiple functions of electrical measurement and stimulation of the patient's heart. A suitable compact AED is described in further detail in Applicant's International Publication No. WO 2018 / 232450, which is incorporated herein by reference in its entirety.

[0099] The defibrillator includes circuitry that allows for the delivery of a pulse of energy to the patient for defibrillation through the electrodes. To provide a sufficient energy pulse to cause defibrillation, the defibrillator circuitry may include one or more capacitors that can store energy and then rapidly discharge it. The capacitors are charged for defibrillation by a power source. In particular in the case of an automated external defibrillator (AED), the power source may be provided as part of the device, for example, by a battery that is part of the AED. In other forms, the power source may be provided external to the AED, for example, via a battery in a mobile device.

[0100] An electronics module (not shown) may be packaged in the enclosure of each of the two pads. The electronics module may include switching circuitry and shock generation circuitry connected to the multiple electrode pairs. The electronics module may further include a controller, such as one or more processors, connected to the switching circuitry and the shock generation circuitry.

[0101] The electronics module may further include other electronic components, such as one or more batteries, transformers, inductors, etc., also packaged in the enclosures of one or both of the two pads. The electronic components of the AED 100 are described in further detail in the applicant's WO 2018 / 232450, referenced above.

[0102] In one embodiment, the energy storage system of the present disclosure includes at least an energy storage system (also referred to as a capacitor system). The energy storage system includes an energy storage bank (also referred to as a capacitor bank). The capacitor bank further includes at least two energy storage blocks. In one embodiment, each of the energy storage blocks includes at least one capacitor. In an alternative embodiment, each of the energy storage blocks according to the present disclosure may include at least three capacitors. The at least three capacitors may include two capacitors connected in series and a third capacitor connected in parallel to one or both of the series connected capacitors.

[0103] The capacitors of the defibrillators according to the present disclosure may be of any suitable type, for example, the capacitors include one or more of a film capacitor or a power film capacitor, a ceramic capacitor, a supercapacitor, or an electrolytic capacitor, or combinations thereof.

[0104] In one embodiment, the energy storage system includes two balancing resistors 101, as shown in Figure 4. In an alternative embodiment, the energy storage system may include diodes (as shown in Figure 5) and / or operational amplifiers connected in series and / or parallel with at least one capacitor in each of the energy storage blocks in addition to the balancing resistors.

[0105] Thus, in a capacitor system including three or more capacitors, the capacitor system may include a series connection between at least two capacitors and a parallel connection between at least two capacitors, i.e., in the case of a three-capacitor system including two capacitors connected in series and another capacitor connected in parallel with one or both of the two series connected capacitors.

[0106] A capacitor system may include one or more banks of capacitors configured in this manner. In at least some configurations, a given capacitor bank may be configured to store and discharge a charge to provide energy for a single phase of a defibrillation waveform.

[0107] The parallel connected elements of the capacitor system may be referred to as parallel energy storage blocks. Each of the parallel energy storage blocks may include one or more capacitors. If it includes more than one capacitor, the capacitors of the energy storage block are connected in series.

[0108] Multiple energy storage blocks may work together as a capacitor bank in a capacitor system to store energy for discharging as a defibrillation shock.

[0109] Because a capacitor bank of a capacitor system includes two or more energy storage blocks, the energy storage blocks of a given capacitor bank may be charged and discharged together.

[0110] 1 illustrates an example of a capacitor system 100 for a defibrillator according to the present disclosure. As can be seen in FIG. 1, the capacitor system 100 is composed of a single capacitor bank 110.

[0111] The energy storage system (or capacitor system) 100 and the energy storage bank (capacitor bank) 110 are composed of a number of energy storage blocks, a first energy storage block 121 and a second energy storage block 122 .

[0112] The first energy storage block 121 has a first capacitor 131 and a second capacitor 132 connected in series with each other. The second energy storage block 122 has a third capacitor 133. The first energy storage block 121 and the second energy storage block 122 are connected in parallel with each other. The series and parallel connections between the capacitors constituting the capacitor system are fixed.

[0113] By configuring a capacitor system according to the present disclosure, an AED may be assembled using individual capacitors of lower operating voltage and / or rated capacitance than would be possible using either individual capacitors or multiple capacitors connected other than in both series and parallel. The configuration described provides a balance of the effects of series and parallel connections on both the overall operating voltage and the overall nominal capacitance.

[0114] When connected in series, a set of capacitors provides a total operating voltage equal to the sum of the individual operating voltages. However, series connection also results in a reduction in the total capacitance relative to the nominal capacitance of the individual capacitors. The total capacitance of capacitors in series is equal to the reciprocal of the sum of the reciprocals of the individual capacitor capacitances. This is expressed by the formula C T =1 / (1 / C 1 +1 / C 2 +1 / C 3 +...), where C T is the total capacitance of the series set, and C 1 is the capacitance of the first capacitor, C 2 is the capacitance of the second capacitor, C 3 is the capacitance of the third capacitor.

[0115] The use of a dual capacitor selection of 30 μF to 60 μF may be selected to provide optimal defibrillation in humans. However, starting with these parameters, there are limitations to producing that capacitance in a small form factor due to current limitations in capacitor technology.

[0116] To generate the required voltage and capacitance, the layout needs to be optimized with respect to the size constraints of the electrical components used in the AED.

[0117]

number

[0118] FIG. 14 illustrates an exemplary embodiment of the capacitor configuration and total capacitance of an AED.

[0119] When connected in parallel, capacitors have an effective capacitance equal to the sum of their individual capacitances and an operating voltage equal to the lowest operating voltage of the capacitor or set of capacitors connected in parallel. Thus, when energy storage blocks having one or more series-connected capacitors are connected in parallel, they will present a composite nominal capacitance that is the sum of the capacitance of each of the energy storage blocks.

[0120] A defibrillator may have a required operating voltage and total capacitance to deliver a desired defibrillation shock to a patient. In accordance with the present disclosure, a given required operating voltage and total nominal capacitance may be provided by using multiple capacitors connected to include capacitors in series with each other and capacitors in parallel with each other.

[0121] The capacitors of the energy storage block may have a nominal capacitance of about 45, 46, 47, 48, 49, 50, 51, 52, 53, 54 or 55 μF, and a useful range may be selected from any of these values ​​(e.g., about 35 to about 55, about 45 to about 53, about 45 to about 50, about 46 to about 55, about 46 to about 52, about 46 to about 50, about 47 to about 55, about 47 to about 53, about 47 to about 50, about 48 to about 55, about 48 to about 53, about 49 to about 55, or about 49 to about 50 μF).

[0122] The capacitors of the energy storage block may have a voltage of about 400, 425, 450, 475, 500, 525, 550, 570 or 600 V, and a useful range may be selected from any of these values ​​(e.g., about 400 to about 600, about 400 to about 550, about 400 to about 450, about 425 to about 600, about 425 to about 500, about 425 to about 450, about 450 to about 600, about 450 to about 550, or about 450 to about 525 V).

[0123] The capacitor of the energy storage block may have a nominal capacitance of about 50 μF and a voltage of about 450 V. The nominal capacitance may be in the range of 6.8 μF to 60 μF and the voltage may be 50 V to 600 V. The capacitance may have requirements to achieve the desired waveform in an available form factor leading to a particular configuration while still achieving the desired waveform.

[0124] In one embodiment, the first bank may be constructed from four parallel sets of three capacitors in series for a total rating of 67 μF and 1350 V. The second bank is two parallel sets of three capacitors in series for a total rating of 33 μF and 1350 V.

[0125] Due to the reduced form factor of the present biphasic defibrillator, one of the challenges of this configuration relates to the overall amount of energy that can be generated by the defibrillator. However, to arrive at the optimal energy required for successful defibrillation, the AED of the present invention is configured such that the optimal dose of the defibrillation shock is derived from determining the appropriate flow of defibrillation current (as seen in Table 1). As a result, the defibrillator of the present invention successfully defibrillates the heart at a lower energy dose. This is not possible with conventional defibrillators, where the focus is on determining the optimal dose.

[0126] Furthermore, the pre-set energy levels vary across different AEDs on the market, ranging from 120J (Zoll AED Pro / Plus) to 360J (Shinglic Heart Save). Figure 15 shows an overall peak-to-peak current graph of different AEDs often used on the market. The graph maps the amount of current in amperes on the X-axis versus the amount of impedance in ohms on the Y-axis. As is evident, the current device (identified as CellAED in the red legend) achieves higher peak current and impedance values ​​compared to other devices on the market, demonstrating the effectiveness of the defibrillator in terms of achieving successful defibrillation outcomes within the patient.

[0127] The electronic components of the present AED may be configured to be operable in a low power and low voltage mode, with the interaction between each of the capacitors being similar to the high power and high voltage components used in conventional defibrillators, which are otherwise several orders of magnitude larger in size than the AED of the present invention.

[0128] An advantage of the present dual bank capacitor configuration is that it can maintain low power mode compatibility and still emulate higher power (and larger) capacitor systems available in conventional defibrillators. Low power mode compatibility can be achieved by performing several adjustments to the components of the charging circuit to account for the smaller battery. For example, adjustments to the circuit may include (a) minimizing the current drawn by the circuit, particularly the continuous "quiescent current", (b) maintaining the voltage supplied during discharge at a constant level by using a regulation circuit, and / or (c) deploying additional components such as a comparator and a generator.

[0129] As shown in Figure 15, the respective component values ​​of the capacitor circuit are shown. In some embodiments, the capacitors include all 50μF, 450V capacitors. The first bank may be constructed from four parallel sets of three capacitors in series for a total rating of 67μF, 1350V. The second bank may include two parallel sets of three capacitors in series for a total rating of 33μF, 1350V.

[0130] The peak current and voltage may be determined based on the transthoracic impedance of a particular patient. A typical reported impedance value is about 50 ohms. Tabular data for peak current and voltage for adults and infants at various impedance values ​​can be found in Tables 1 and 2.

[0131] [Table 1]

[0132] [Table 2]

[0133] As can be seen from Tables 1 and 2, the actual voltage achieved by the defibrillator of the present invention is lower than that of the conventional defibrillator.

[0134] It will be appreciated that the energy storage system and individual energy storage banks may be constructed in accordance with the above principles to provide a capacitor system that matches a desired set of defibrillation waveform characteristics.

[0135] The shock waveform may be of the type that has equal leading edges for peak current in both phases of a biphasic defibrillator. The waveform may be a full ramp waveform that allows for efficient energy application during defibrillation shock, ultimately resulting in lower overall energy.

[0136] The waveform may have several important parameters toward successful defibrillation, including any one or more of the following: Phase 1 Peak Current Phase 1 Duration Phase 2 Peak Current Phase 2 Duration

[0137] The duration of the first phase may have a minimum time (tp1) that must be achieved to ensure that the defibrillation shock reaches all cells of the myocardium to achieve a polarizing effect. The duration of the second phase is not essential and is secondary to the first phase. The total duration of the shock is also adjusted, as shocks observed for longer periods can lead to arrhythmias.

[0138] The magnitude of the shock (peak current) must be sufficient to polarize the cardiac cells in the first phase and depolarize them in the second phase. The optimal peak currents observed are shown in Table 1 for adults and Table 2 for infants.

[0139] It will also be appreciated that current and time (not energy) are the most important factors for defibrillation efficiency. The energy of a shock may be calculated as energy = current x voltage x time. It is therefore clear that energy output is not a measure of favorable outcome, but rather a by-product of current and time.

[0140] Referring to Figure 15, a comparison of the claimed defibrillator against several existing conventional biphasic defibrillators is shown. The results demonstrate that the peak-to-peak currents are similar between all devices, highlighting the importance of current to defibrillation effectiveness. Finally, the claimed defibrillation waveform has a peak-to-peak current comparable to other devices, but the full ramp waveform allows the present defibrillator to apply energy more efficiently, resulting in lower overall energy.

[0141] Furthermore, conventional biphasic waveform-based defibrillators use a partial ramp truncation waveform to achieve a defibrillation shock in both phases, i.e., midway through the shock, a switch is used to change the direction of the current and therefore the phase of the shock, but the current is sourced from the same capacitor.

[0142] The difference in this design of the energy storage system is the use of two independent energy storage banks. A controller may be configured to operate the switching circuitry and the shock generation circuitry such that an electrical switching operation is performed, with each of the energy storage banks (including storage blocks) being used for a specific phase to achieve a full slope and equal leading edge waveform that cannot be produced without that separation.

[0143] The use of two capacitor banks to achieve a biphasic waveform in this configuration may reduce the complexity of the electrical circuitry and the number of switches compared to a single capacitor bank, making the design more efficient and therefore resulting in a smaller form factor for the defibrillator.

[0144] It is further understood that modern conventional biphasic waveforms use a partially ramped truncated waveform to achieve both phases, i.e., mid-shock, a switch is used to change the direction of the current, thus changing the phase of the shock, however, the current is delivered from the same capacitor.

[0145] In contrast, by using the two energy storage bank configuration of the present device, the controller is configured to control the switching circuitry and the shock generation circuitry such that each of the energy storage banks (including the energy storage blocks) is used for a particular one of the two phases (i.e., either the first phase or the second phase). For example, the two energy storage banks are independent of each other for each of the two phases of the defibrillation shock.

[0146] In this embodiment, the switching circuitry is configured to perform electrical switching operations such that one of the energy storage blocks is configured to charge, store, and discharge to provide energy to one of the two phases, and the other of the energy storage blocks is configured to charge, store, and discharge to provide energy to the other of the two phases of a defibrillation shock.

[0147] In addition, the switching circuitry is also configured to perform electrical switching operations such that the direction of current flow is maintained to be the same during each of the two phases during a defibrillation shock, i.e., in this configuration, the shock direction of current flow does not change midway, so that the original direction in which the current began in each of the two phases remains the same (or is maintained to be the same).

[0148] This configuration therefore results in perfectly tilted, equal leading edge waveforms that can be generated necessarily with separation of the two phases (ie, independent blocks for each phase).

[0149] Equal leading edge waveforms are generally associated with equal peak currents between the first and second phases. In the present defibrillator, since the phases are processed with separate energy storage banks, the defibrillator has equal current (peak current) and voltage parameters for each phase, even with different capacitance values. However, in conventional AEDs, the voltage of the second phase is usually lower than the first phase, since the capacitor(s) are partially discharged and lose voltage before the start of the second phase. This effect is not observed here.

[0150] In this embodiment, the controller may be configured to perform electrical switching operations to provide defibrillation shocks in the two phases such that the voltage and peak current in each of the two phases are substantially the same.

[0151] The controller may be further configured to operate the shock generation circuitry and the switching circuitry to automatically perform electrical measurements and stimulation of the patient's heart switching between the two phases.

[0152] Furthermore, in this configuration, by selecting the operating voltage and nominal capacitance of the capacitors used, placing the capacitors in series sets to provide the desired overall operating voltage, and connecting these sets in parallel to increase the overall capacitance, an energy storage system according to the present disclosure can be matched to the desired operating voltage and nominal capacitance of a defibrillator.

[0153] The controller may be further configured to generate a predetermined dose of current for a defibrillation shock at a predetermined dose of power, the determination being based on pre-set / pre-defined values ​​for an adult or an infant as reported in Tables 1 and 2, respectively.

[0154] Capacitors having a lower operating voltage and / or rated capacitance may be of reduced size in at least one dimension for the same capacitor type. Capacitors having a lower operating voltage and / or rated capacitance may also be of reduced cost for the same capacitor type. In particular, the total cost of three or more lower rated capacitors may be less than or significantly less than the price of a fewer number of higher rated capacitors.

[0155] Thus, an AED having a capacitor system constructed in accordance with the present disclosure may be able to provide either or both a reduced overall cost of the capacitor system and a capacitor system that can be constructed in a form that is smaller in at least one dimension than would otherwise be possible. Efficient design of electrical circuits using low power components is the basis for reducing the form factor of the present defibrillators, since low power electrical components are smaller in size.

[0156] A reduction in complexity and number of switches may be achieved using two separate capacitor banks to achieve a biphasic waveform, as compared to a single capacitor bank, making the designs described herein more practical and efficient.

[0157] Each pad of the defibrillator is approximately 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200 cm 3 and a useful range may be selected from any of these values ​​(e.g., about 100 to about 200, about 100 to about 180, about 100 to about 160, about 100 to about 150, about 110 to about 200, about 110 to about 190, about 110 to about 170, about 110 to about 150, about 120 to about 200, about 120 to about 180, about 120 to about 150, about 130 to about 200, about 130 to about 180, about 130 to about 150, about 140 to about 200, about 140 to about 180, about 140 to about 160, or about 140 to about 150 cm). 3 ).

[0158] Each pad of this defibrillator is approximately 50, 60, 70, 80, 90 or 100 cm 2 and a useful range may be selected from any of these values ​​(e.g., about 50 to about 100, about 50 to about 80, about 50 to about 70, about 50 to about 60, about 60 to about 100, about 60 to about 80, about 60 to about 70, or about 50 to about 60 cm). 2 ).

[0159] For example, the volume of each pad is approximately 9.7 cm x 9.3 cm x 1.7 cm, or 153 cm 3 The total volume may be given as 8.2 cm x 8.6 cm, and the surface area is 70.5 cm 2 may be given a total surface area of

[0160] The series and parallel connections between the capacitors of the capacitor system, or at least a given capacitor bank, may be fixed. In such a configuration, the connections between the capacitors have non-switching connections therebetween. This may provide simplicity and reliability compared to configurations in which switches are included to change the series and parallel configuration of one or more capacitors.

[0161] When the connections between the capacitors are fixed, the capacitors are arranged in the same series and parallel relationships for both capacitor charging and capacitor discharging. Although increased charging efficiency may be obtained by charging capacitors in parallel, the use of fixed connections in a capacitor system that includes capacitors connected in both series and parallel may result in a relative decrease in charging efficiency. However, any such reduced charging efficiency may be offset by the increased simplicity and reliability offered by the fixed connections.

[0162] The capacitors may, at least in some configurations, be cylindrical or at least notionally cylindrical in shape having a diameter and a longitudinal axis. The capacitors may be arranged in a planar configuration. Alternatively, the capacitors may have a mixed configuration, with some planar and some vertical.

[0163] FIG. 2 is a simplified circuit diagram of a defibrillator 10, such as an AED, that includes the capacitor system 100 of FIG.

[0164] Figure 16 is an alternative simplified circuit diagram of a defibrillator 10, such as an AED, that includes the capacitor system 100 of Figure 1. As shown in this figure, the energy storage system includes two energy storage banks that include at least one capacitor 101 (highlighted in red).

[0165] 2, the defibrillator 10 charges a capacitor system with energy from a battery 17. Before reaching the capacitor system 100, the voltage from the battery 17 is stepped up through a transformer 18. The operation of the transformer 18 to charge the capacitor system 100 is controlled by a controller 19, which also controls the operation of a switch 21 to allow the discharge of the capacitor system 100 to the two electrodes 14 and 15 connected across the patient 1.

[0166] The series and parallel connections between the capacitors 131-133 of the capacitor system 100 are fixed to be the same during both charging the capacitors and discharging them to the patient.

[0167] Each of the capacitors 131-133 in the capacitor system has a nominal capacitance and an operating voltage, and therefore the capacitor system 100 has an overall nominal capacitance and operating voltage based on the specifications of the individual capacitors.

[0168] Although shown in conceptual form in Figures 1 and 2, it will be appreciated that additional capacitor systems may be constructed by applying the same principles to meet the desired defibrillation waveform of a defibrillator, particularly an AED.

[0169] Additionally, although the illustrated circuit configuration of Figure 2 may provide for the delivery of only a monophasic defibrillation shock to a patient, the capacitor system of the present disclosure may be utilized in defibrillators that provide other types of defibrillation shocks, for example, biphasic or countershock defibrillation pulses are common standards in AEDs.

[0170] Each phase of the biphasic shock may be provided by each of the two energy storage blocks by incorporating an H-bridge into the circuit of FIG.

[0171] Other configurations may utilize separate capacitors to provide each respective biphasic phase. Such configurations may also utilize an H-bridge to switch the polarity at which charge is applied across the electrodes between the two phases.

[0172] When capacitors are connected in series as part of an energy storage block, one or more charge balancing resistors may be connected across each of the series capacitors to balance the charge across each capacitor. For example, Figure 3 shows the capacitor system 100 of Figures 1 and 2, but with the first energy storage block 121 including charge balancing resistors 101 and 102 associated with the first capacitor 131 and the second capacitor 132, respectively.

[0173] 4 is a portion of a circuit diagram of a defibrillator 10, such as an AED, showing a capacitor system 100 and electrodes 14 and 15. The capacitor system 100 has a first capacitor bank 111 and a second capacitor bank 112. The first capacitor bank 111 is for delivering a first phase of a biphasic defibrillation shock. The second capacitor bank 112 is for delivering a second phase of a biphasic defibrillation shock.

[0174] The first capacitor bank 111 may be comprised of a first energy storage block 121 and a second energy storage block 122. The first energy storage block 121 may have capacitors 131 and 132 connected in series. The second energy storage block 122 may include a single capacitor 133.

[0175] The second capacitor bank 112 may include a third energy storage block that may have capacitors 134 and 135 connected in series, and a fourth energy storage block that may have a single capacitor 136.

[0176] The energy storage blocks 121 and 122 of the first capacitor bank 111 may be connected in parallel. Similarly, the energy storage blocks 123 and 124 of the second capacitor bank 112 may be connected in parallel.

[0177] Both the first energy storage block 121 and the third energy storage block 123 may include balancing resistors 101a-101d connected across each of the respective series-connected capacitors.

[0178] 4 are connected to respective electrodes 14 and 15 by four switches 21-24 that provide the function of an H-bridge. By selective operation of switches 21-24, such as by controller 19, capacitor banks 111 and 112 of capacitor system 100 may be discharged in sequence to provide a biphasic defibrillation shock.

[0179] The switch may be of any commonly available form, such as a transistor (eg, a FET or BJT switch) or a relay.

[0180] The nominal capacitance and operating voltages of capacitor banks 111 and 112 may be the same or different, as desired to provide the desired biphasic defibrillation shock.

[0181] The capacitor system 100 or capacitor bank may include only three capacitors, although in at least some configurations the capacitor system or capacitor bank may include four or more capacitors connected in series and parallel combinations.

[0182] The capacitors of a capacitor system according to the present disclosure may be selected to provide a desired operating voltage and / or nominal capacitance for one or each of the individual energy storage blocks, each capacitor bank, and the entire capacitor system. For example, the number of capacitors in each energy storage block and their individual operating voltages and nominal capacitances may be selected to provide, as a result of their series and parallel combinations, a particular operating voltage and / or nominal capacitance for a given energy storage block, a particular one of the capacitor banks, or the entire capacitor system as a whole.

[0183] In some configurations, the capacitors of a capacitor bank, or even the capacitors of an entire capacitor system, may be selected to have the same operating voltage.

[0184] Different energy storage blocks of the same capacitor bank may contain different numbers of capacitors, but to maximize efficiency, it may be preferable for the total operating voltage of each energy storage block to be the same. Otherwise, the other blocks would be charged below their operating voltage so as not to exceed the total operating voltage of the lowest rated energy storage block.

[0185] Energy storage blocks with the same total operating voltage may be provided by a series combination of either the same capacitor or different capacitors.

[0186] In at least some configurations, the capacitors in a capacitor bank or an entire capacitor system may be selected to have at least one physical dimension in common. For example, for cylindrical capacitors, the capacitor specifications, such as nominal capacitance and operating voltage, may be the same or different, but at least one of the diameter of the capacitors and their lengths may be the same or substantially the same.

[0187] By using capacitors with common dimensions, the corresponding size of the defibrillator or defibrillator component that includes the capacitor can be reduced.

[0188] 5 is a simplified circuit diagram of a defibrillator including a capacitor system 100 consisting of a first capacitor bank 111 and a second capacitor bank 112. Each of the capacitor banks 111 and 112 consists of two energy storage blocks 121-122 and 123-124, each having two of the capacitors 131-138 connected in series. A balancing resistor 101 is connected across each of the capacitors 131-138.

[0189] As seen in FIG. 5, the capacitor system side of transformer 18 is shown connected to zero voltage node 31.

[0190] 5, the energy storage blocks 121 and 122 of the first capacitor bank 111 may have the same operating voltage. This may be provided by a) a respective pair of capacitors of each of the energy storage blocks 121 and 122 having the same operating voltage, b) each capacitor having a different operating voltage (e.g., capacitor 131 having an operating voltage of 200V and capacitor 132 having an operating voltage of 300V for the first energy storage block 122 having an operating voltage of 500V, and capacitor 133 having an operating voltage of 150V and capacitor 134 having an operating voltage of 350V for the second energy storage block 121 having an operating voltage of 500V), or c) each of the capacitors 131-134 having the same operating voltage.

[0191] An extension of the same considerations applies to capacitor banks having three or more capacitors in series within one or each energy storage block.

[0192] As can be seen in FIG. 5, the capacitors in each of capacitor banks 111 and 112 have a fixed, non-switching relationship to one another, so that the capacitors are charged and discharged in the same series and parallel configurations.

[0193] 6A and 6B are circuit diagrams of another example configuration of a capacitor bank 110. In some configurations, the capacitor bank 110 may form a capacitor system 100. In other configurations, the capacitor system 100 may include two or more capacitor banks 110.

[0194] The energy storage bank 110 of Fig. 6A includes a first energy storage block 121 and a second energy storage block 122, as shown in Fig. 6B. Each of the energy storage blocks 121 and 122 includes four capacitors 131-134 and 135-138. A balancing resistor 101 is connected across each of the capacitors.

[0195] 6A and 6B, the capacitors of each energy storage block may be selected to have at least similar, or preferably the same, total operating voltage. The total nominal capacitance of each energy storage block 121 and 122 may be the same or different.

[0196] Capacitors 131 and 132 may include the same set of capacitors.

[0197] Capacitors 131 and 132 may each have the same operating voltage and / or nominal capacitance.

[0198] Capacitors 131 and 132 may each have at least one dimension in common, for example if the capacitors are of cylindrical type, they may each have the same, or at least approximately the same, diameter or length.

[0199] A capacitor bank of a capacitor system may be comprised of a corresponding number of energy storage blocks and / or capacitors, although in at least some configurations, different capacitor banks of a capacitor system may be comprised of one or both of different numbers of energy storage blocks and different numbers of capacitors. The capacitor banks may also have the same or different total operating voltages and nominal capacitances.

[0200] If separate capacitor banks are used to discharge each phase of the defibrillation shock, the configuration of each capacitor bank may be customized to provide the desired characteristics of each phase.

[0201] For example, in at least some configurations, it may be desirable to deliver more defibrillation energy in the first defibrillation pulse than in the second defibrillation pulse.

[0202] 7 is a partial circuit diagram of a defibrillator showing a capacitor system 100 having a first capacitor bank 111 and a second capacitor bank 112 and an H-bridge formed by switches 21-24 to selectively connect the capacitor banks 111 and 112 to electrodes 14 and 15. A patient 1 is shown between two electrodes 114 and 115.

[0203] The first capacitor bank 111 is made up of five energy storage blocks 121-125, each of which includes four series-connected capacitors 131 with a balancing resistor 101 connected across each capacitor.

[0204] The second capacitor bank is comprised of three energy storage blocks 126-128, each of which similarly includes four series-connected capacitors 132 with a balancing resistor 101 connected across each capacitor.

[0205] The capacitors in the first capacitor bank may be capacitors of the same operating voltage and nominal capacitance rating, or they may include a set of capacitors of different ratings, or alternatively, they may each be rated differently from one another, as well as the capacitors in the second capacitor bank.

[0206] In addition to or in lieu of any particular configuration of capacitor ratings, one or both capacitors of a capacitor bank may share at least one physical dimension, for example, if the capacitors are cylindrical, they may have a common diameter and / or length.

[0207] In a configuration in which capacitors 131 and 132 each have a common operating voltage and / or nominal capacitance, or in which at least each of energy storage blocks 121-128 have a common overall operating voltage and / or nominal capacitance, the second capacitor bank 122 has a lower total energy capacity than the first capacitor bank 121.

[0208] FIG. 8 is a partial circuit diagram of a defibrillator showing another configuration of the capacitor system 100. The capacitor system 100 of FIG. 8 includes a first capacitor bank 111 and a second capacitor bank 112. The capacitor banks 111 and 112 are connected to the electrodes 14 and 15 by four switches 21-24 operating as an H-bridge. The capacitor banks 111 and 112 each include an energy storage block 120 having four capacitors 131-134 connected in series. The first capacitor bank 111 includes six energy storage blocks 120, and the second capacitor bank 112 includes four energy storage blocks 120. Each capacitor of each energy storage block 120 includes a balancing resistor 101 connected across the capacitor to balance the charge between the capacitors 131-134 of the respective energy storage block 120.

[0209] In the configuration of FIG. 8, where each energy storage block 120 has the same total operating voltage and nominal capacitance, the first capacitor bank 121 may have 50% more energy storage capacity than the second capacitor bank 122.

[0210] While the above provides examples of capacitor systems and capacitor banks of capacitor systems, it will be understood that many other configurations of capacitor systems and their capacitor banks may be arrived at through application of the above principles in combination with fixed connected capacitors to include capacitors connected in both series and parallel. In particular, capacitors may be selected and arranged within the energy storage block to provide a desired capacitor bank, and overall capacitor system, having any desired operating voltage and / or nominal capacitance.

[0211] For example, according to one configuration of an AED, it may be desired for the capacitor system to deliver a first phase of a biphasic defibrillation shock of approximately 2 kV with a total phase energy of approximately 20 J. This would require a first phase power supply having a nominal capacitance of approximately 10.2 μF.

[0212] Such a configuration may be provided, for example, by a first capacitor bank having six energy storage blocks, each including four series-connected capacitors having an operating voltage of 450 V and a nominal capacitance of 50 μF.

[0213] By way of further example, in this configuration, a second phase may be required to deliver the second phase of a biphasic defibrillation shock of approximately 2 kV with a total phase energy of approximately 16.5 J. This would require a second phase power supply having a nominal capacitance of approximately 6.8 μF.

[0214] These specifications may be provided, for example, by a second capacitor bank having four energy storage blocks, each containing four series-connected capacitors, each having an operating voltage of 450V and a nominal capacitance of 50μF.

[0215] In this example, each capacitor bank is constructed with capacitors of the same specifications, and the capacitor specifications are the same between the two capacitor banks. Such a configuration may allow for the use of physically identical capacitors, which may have the same dimensions. For example, if the capacitors are cylindrical capacitors, each of the capacitors in each capacitor bank, and the capacitor system as a whole, may have the same diameter and length. This may allow for an increase in efficiency in the dimensions of the AED or AED component in which the capacitors are provided.

[0216] In another example, according to another configuration of the AED, it may be desired for the AED to deliver a total biphasic defibrillation energy of about 100 J. This energy may be distributed unequally between the two phases, for example, about 67 J delivered by the first phase and about 33 J delivered by the second phase. For purposes of this example, each of the defibrillation phases may need to be delivered at about 1.5 kV.

[0217] These specifications call for a working capacitance of approximately 60 μF for the first phase and a nominal capacitance of approximately 30 μF for the second phase.

[0218] For the first phase, this may be provided, for example, by a first capacitor bank with four energy storage blocks, each having an operating voltage of 450 V and three series-connected capacitors with a nominal capacitance of 67 μF and 1350 V, respectively. For the second phase, the specified nominal capacitance may be provided, for example, by a second capacitor bank with two energy storage blocks, each having an operating voltage of 450 V and three series-connected capacitors with a nominal capacitance of 33 μF and 1350 V, respectively.

[0219] Such characteristics may include, in the case of biphasic defibrillation, one or more of the peak voltage of one or both phases and the total defibrillation energy of each respective phase or both phases.

[0220] In at least some embodiments, electrolytic capacitors may be utilized in the capacitor system due to factors such as the relatively high capacitance per unit volume that they can provide.

[0221] More specifically, but not by way of limitation, in some configurations, rolled electrolytic capacitors may be utilized.

[0222] Although in some of the foregoing examples the capacitor banks individually, and the capacitor system as a whole, are composed of identically rated capacitors, it will be understood that the same total operating voltage and phase energy requirements may be provided by other combinations of any number of differently rated capacitors when combined in parallel connected energy storage blocks including at least one series connected capacitor.

[0223] However, in at least some preferred configurations, the total operating voltage of each energy storage block of a given capacitor bank will be approximately equal, and at least one physical dimension of each of the capacitors of a given capacitor bank will be approximately equal.

[0224] In at least some of the foregoing examples, the operating voltages of both the first and second capacitor banks are equal, however, in some configurations, the capacitor banks may have unequal operating voltages in addition to or in lieu of different total nominal capacitances as necessary to provide desired defibrillation phase waveform characteristics.

[0225] As mentioned above, in at least some configurations, the capacitors or the entire capacitor system of the capacitor bank may share only one dimension, either diameter or length, such as in the case of cylindrical capacitors.

[0226] The present disclosure also provides defibrillators, and in particular AEDs, having one or more particular spatial arrangements of capacitors provided as part of the AED.

[0227] Many factors can affect the availability of AEDs when and where they are needed to treat sudden cardiac arrest. Price can be an important factor in determining the widespread availability of AEDs, especially in less affluent communities and regions. The weight and / or physical size of the device can also be an important factor in determining when and where AEDs are available. The weight of an AED can impose practical limitations on whether people are willing to carry an AED on their own or keep one on hand in case of an emergency. Similarly, the physical dimensions of an AED can limit how much one can practically lift it. For example, a large device may be impractical for a person to carry or to keep within reach in everyday situations such as the workplace, vehicle, or home.

[0228] In accordance with at least some configurations of the present disclosure, a defibrillator, such as an AED, may be provided that has a reduced size in at least one dimension.

[0229] 9A is a diagram of the housing 16. In various configurations, the housing 16 may be the housing of an integrated single-piece defibrillator such as an AED, the housing of an electrode pad module in which the components of the AED are associated with pads, or the housing of a defibrillator base unit to which each of the electrode pads are connected.

[0230] 9A, capacitor 211 is shown within housing 16. Housing 16 has height 301, width 302, and depth 303. Capacitor 211 has a diameter D 1 and length L 1 The capacitor 221 has a cylindrical axis 310.

[0231] At least one, and potentially all three, dimensions of the housing 16 are equal to or greater than the diameter D of the capacitor 221. 1 and length L 1 For example, as seen in FIG. 9A, the height 301 of the housing 16 may be limited by the diameter D of the capacitor 211. 1 is limited by

[0232] FIG. 9B shows another example of a housing 16 as described in connection with FIG. 3A, but the housings each have a diameter D 1 and length L 1 (not shown). In this configuration, both the height 301 and the width 302 of the housing 16 are equal to the diameter D of the two capacitors 211 and 212. 1 is limited by

[0233] FIG. 10A shows a cross-sectional view of a pair of 10-way gyroscopes, each with a diameter of D 2 and length L 21 shows another housing 16 having a plurality of capacitors 131-135 having a plurality of electrodes (not shown). The plurality of capacitors 131-135 may be capacitors of a capacitor system of the present disclosure.

[0234] Diameter D of capacitors 131 to 135 2 is smaller than the diameter of capacitors 211 and 212 of Figures 9A and 9B. Thus, as shown in Figure 10B, the height 301 of housing 16 of Figure 4A may be reduced relative to, for example, the housing of Figures 9A or 9B, or 10A, to provide a defibrillator or portion of a defibrillator that is of a relatively reduced size in one dimension. This reduction may further enable a reduction in the overall volume of housing 16.

[0235] Each of the capacitors 131-135 has a cylindrical axis 310 as shown in capacitor 131 of Figure 10A. As seen in Figures 10A and 10B, the cylindrical axis of each of the capacitors 131-135 is oriented parallel to the length 303 of the housing 16. Alternatively, the capacitors have a longitudinal axis (not shown).

[0236] As can be seen in FIGS. 10A to 10C, capacitors 131 to 135 are arranged such that their cylindrical axes are parallel.

[0237] Figure 10C shows a conceptual plane 320. In the configuration shown in Figure 10C, capacitors 131-134 are arranged such that their cylindrical axes pass through plane 320. The cylindrical axes of the capacitors may be said to be coplanar with plane 320 in this configuration.

[0238] In some configurations, the housing 16 may include or be associated with electrode pads. The electrode pads may have a planar shape. In such configurations, if the cylindrical axis of the capacitor 131 lies in the plane 320, the plane 320 may also be parallel to the plane of the electrode pads.

[0239] As can be seen in FIG. 10C, capacitors 131 - 134 are oriented such that their cylindrical axes are perpendicular to length 303 of housing 16 .

[0240] The capacitor system of the present disclosure may be included in a defibrillator, for example, an AED. An exemplary form of AED 10 is shown in Figure 11 deployed for use on the torso of a patient 1. The patient's heart 2 is shown in dashed lines within the patient's chest.

[0241] The AED 10 of Figure 11 has a first pad module 11 and a second pad module 12 with a connecting wire 13 connecting the two modules. Electrodes or electrode pads 14 and 15 are located on the patient-facing sides of the pad modules 11 and 12 for delivering defibrillation shocks to the patient. The necessary operating components of the AED 10, in particular the capacitor system 100, may be located as part of one or both of the pad modules 11 and 12.

[0242] In other configurations, such as when the AED 10 has a base module that connects to the two electrode pads 14 and 15, some or all of the other operational components of the AED, including in particular the capacitor system, may be located in the base unit.

[0243] 13A-13C are schematic plan views of different configurations of a capacitor system 100 in an AED 10 having two pad modules 11 and 12. FIG.

[0244] In addition to or instead of being axially parallel, two or more of the capacitors of a capacitor system may be coaxially arranged, as shown, for example, in Figure 13A by capacitors 131 and 139 being in parallel.

[0245] In Figure 13A, capacitors 131-146 form a capacitor system 100. The capacitors 131-146 are provided as part of a first pad module 11. This configuration is also shown in Figure 13C.

[0246] In FIG. 13B, capacitors 131 to 146 constituting the capacitor system 100 are distributed between the first pad module 11 and the second pad module 12. In FIG.

[0247] When the capacitor system 100 includes multiple capacitor banks, the physical arrangement of the capacitors within the capacitor system may reflect, at least in part, the assignment of the capacitors to the banks.

[0248] For example, in the configuration of Figure 13A, capacitors 131-138 may belong to a first capacitor bank, and capacitors 139-146 may belong to a second capacitor bank. In such a configuration, the capacitors in each bank may be coaxially aligned with corresponding capacitors in the other bank. In this configuration, the axes of the capacitors may also lie in a common plane.

[0249] 13A, capacitors 131-134 and 139-142 may belong to a first capacitor bank, and capacitors 135-138 and 143-146 may belong to a second capacitor bank. In such a configuration, the capacitors of each phase may be coaxially aligned with another capacitor of the same phase.

[0250] Figure 13C shows a configuration where there are two capacitor banks 111 and 112 with an unequal number of capacitors. The capacitors in capacitor banks 111 and 112 are labeled with "X" and "Y", respectively. As can be seen in Figure 13C, the capacitors are arranged in two rows so that the capacitors in each row are coaxially aligned with corresponding capacitors in the other row.

[0251] The capacitors of the capacitor system may be arranged in any desired number of columns and rows in a defibrillator, particularly an AED.

[0252] The capacitor system may include multiple layers of capacitors, with the layers oriented into or out of the plane of the schematic diagrams of Figures 13A-13C.

[0253] However, in at least some preferred configurations, the capacitors of a capacitor system according to the present disclosure may be arranged in a single layer.

[0254] In some configurations, a capacitor system having capacitors arranged such that the longitudinal axes of each capacitor lie in a common plane may have capacitors connected in fixed combinations of both series and parallel, for example as described in connection with Figures 1-8.

[0255] However, in other configurations, the capacitor system may have capacitors arranged such that the longitudinal axes of each capacitor lie in a common plane, but connected together in other than a fixed series and parallel combination.

[0256] A capacitor system according to the present disclosure may be charged and discharged in the operation of a defibrillator, such as an AED. If the capacitor system includes more than one bank of capacitors, the banks may be charged from a power source either continuously or simultaneously. If the capacitor system includes more than one bank of capacitors, the banks may be discharged all at the same time, one at a time, or in different combinations as desired to provide a desired defibrillation waveform.

[0257] A capacitor system according to the present disclosure may be manufactured by first fixedly connecting a number of capacitors in series to form an energy storage block. A number of these energy storage blocks may be formed. The energy storage blocks may be fixedly connected together in parallel to form the capacitor system.

[0258] The steps of assembling the energy storage blocks and joining them together in parallel may be completed in either order or simultaneously.

[0259] Although generally described in connection with an AED, the capacitor system of the present disclosure may be utilized as part of other types of defibrillators, such as an implantable cardioverter defibrillator (ICD), an extra-cardiac implantable defibrillator (EID), or other forms of non-AED external heart defibrillators (EHD).

[0260] In one embodiment, the voltage ratio between both banks may be equal. In another embodiment, the voltage ratio may be different. Similarly, the energy storage ratio in a particular embodiment is about 2:1. Depending on the configuration and requirements, this ratio may vary.

[0261] The method of operating an AED that has two pads that are placed on the patient is as follows: (i) performing the functions of electrical measurement and stimulation of the patient's heart; (ii) operating the controller to perform electrical switching operations to provide a defibrillation shock in two phases, the voltage and peak current in each of the two phases being substantially the same.

[0262] In one embodiment, the peak current and voltage in the first phase are maintained until a first time interval tp1, during which a polarization effect is observed in the patient. The first time interval is the time it takes for a defibrillation shock to reach all cells of the patient's myocardium. Multiple functions of electrical measurement and stimulation of the patient's heart, performed by one or more electrodes in multiple directions, include: (i) measuring cardiac electrical signals to detect the positions of two pads; (ii) measuring an ECG signal to detect a shockable cardiac rhythm; (iii) if a shockable cardiac rhythm is detected, delivering, via the two pads, a defibrillation shock with a dosage based on the detected location of the pads.

[0263] Where reference is made in the foregoing description to elements or integers that have known equivalents, such equivalents are included as if they were individually set forth.

[0264] Although the embodiments have been described with reference to some exemplary embodiments, it will be understood by those skilled in the art that various changes in form and details can be made without departing from the spirit and scope of the present invention as defined by the appended claims. Therefore, the preferred embodiments are for the purpose of illustrating the present invention and are not intended to limit the present invention, and the technical scope of the present invention is not limited to the embodiments. Furthermore, the present invention is defined by the claims, not by the detailed description of the invention, and all differences within the scope will be interpreted as being included in the present invention.

[0265] Many modifications will be apparent to those skilled in the art without departing from the scope of the invention as described herein with reference to the accompanying drawings.

Claims

1. two pads for placement on a patient, each of the two pads including an energy storage system, the energy storage system including at least two energy storage blocks; a switching circuit and a shock generating circuit connected to the two pads; a controller connected to the switching circuit and the shock generation circuit, the controller configured to perform electrical switching operations to provide defibrillation shocks in the two phases such that a voltage and a peak current in each of the two phases are substantially the same.

2. 2. The AED of claim 1, wherein the at least two energy storage blocks are independent of each other for each of the two phases of the defibrillation shock.

3. 3. The AED of claim 1, wherein at least two of the energy storage blocks are connected in parallel, each of the energy storage blocks including at least one capacitor, and at least one of the energy storage blocks includes two or more capacitors in series.

4. 4. The AED of claim 3, wherein the series and parallel arrangements of the capacitors are the same both during charging of the energy storage block and during discharging of the energy storage block to provide a defibrillation shock.

5. Each of the two pads is approximately 100 cm ３ ~200cm ３ and a volume of approximately 50 cm ２ ~100cm ２ 10. The AED of claim 1 having a surface area of

6. 10. The AED of claim 1, wherein the controller is further configured to generate equal leading edge waveforms for each of the two phases.

7. 10. The AED of claim 1, wherein the controller is further configured to generate a predetermined dose of current for a defibrillation shock at a predetermined dose of power.

8. 10. The AED of claim 1, wherein the controller is further configured to maintain a peak current in each phase such that a polarization effect is observed in a first phase and a depolarization effect is achieved in a second phase.

9. 10. The AED of claim 1, wherein the controller is further configured to generate a full gradient waveform for each of the two phases.

10. 2. The AED of claim 1, wherein the switching circuitry is configured to perform electrical switching operations such that one of the energy storage blocks is configured to charge, store, and discharge to provide energy for one of the two phases, and the other of the energy storage blocks is configured to charge, store, and discharge to provide energy for the other of the two phases of the defibrillation shock.

11. 11. The AED of claim 10, wherein the switching circuitry is configured to perform electrical switching operations such that the direction of current flow is maintained during each of the two phases during the defibrillation shock.

12. 10. The AED of claim 1, wherein each of the capacitors of at least one of the energy storage blocks has the same or substantially the same nominal capacitance and operating voltage.

13. 2. The AED of claim 1, wherein each of the energy storage blocks further includes one or more of a balancing resistor, a diode, or an operational amplifier connected in series and / or parallel with at least one of the capacitors in each of the energy storage blocks.

14. 2. The AED of claim 1, further comprising any one or more of a transformer, an electrical switch, a battery, and an inductor, wherein each of the transformer, the electrical switch, the battery, and the inductor is configured to be operable in a low-voltage mode or a low-power mode.

15. 2. The AED of claim 1, wherein the shock generation circuit includes a charging circuit and / or a discharging circuit configured to charge and / or discharge one or more of the capacitors of the energy storage block.

16. 2. The AED of claim 1, wherein the controller is configured to operate the shock generation circuitry and the switching circuitry to automatically perform electrical measurements and stimulation of the patient's heart that alternate between the two phases.

17. 2. The AED of claim 1, wherein each of the two pads includes one or more electrodes, and at least one of the electrodes on each of the two pads is configured to perform at least one of electrical measurements and stimulation of the patient's heart.

18. 2. The AED of claim 1, wherein the energy storage system includes at least six energy storage blocks, four energy storage blocks configured to charge, store, and discharge to provide energy for the first of the two phases of the defibrillation shock, and two other energy storage blocks configured to charge, store, and discharge to provide energy for the second of the two phases of the defibrillation shock.

19. 10. The AED of claim 1, wherein at least two of the energy storage blocks are connected in parallel, and each of the energy storage blocks includes at least one capacitor.

20. 1. A method of operating an AED having two pads for placement on a patient, the method comprising: performing a plurality of functions of electrical measurement and stimulation of the patient's heart; operating a controller to perform electrical switching operations to deliver a defibrillation shock in two phases, wherein the voltage and peak current in each of the two phases are substantially the same.

21. 21. The method of claim 20, wherein the peak current and the voltage in a first of the two phases of the defibrillation shock are maintained until a first time interval tp1 during which a polarization effect is observed in the patient.

22. 22. The method of claim 21, wherein the first time interval is the time it takes for the defibrillation shock to reach all cells of the patient's myocardium.

23. the plurality of functions of electrical measurement and stimulation of the patient's heart performed by one or more electrodes in multiple directions; measuring cardiac electrical signals to detect the positions of the two pads; measuring an ECG signal to detect a shockable cardiac rhythm; and if a shockable cardiac rhythm is detected, delivering, by the two pads, a defibrillation shock of a dosage based on the detected positions of the two pads.

24. 24. The method of any one of claims 20 to 23, wherein the measured cardiac electrical signals used to detect the position of the two pads include voltage, current, impedance, or any combination thereof.

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