Embodiments disclosed herein relate to systems and methods for a wearable lifesaving defibrillator.
Automated External Defibrillators (AED) are portable devices used to defibrillate patients having a sudden cardiac arrest (SCD) event, generally due to ventricular tachycardia (VT) or ventricular fibrillation (VF). When a person loses consciousness, and there is a chance of VT or VF, an AED is brought to the patient for use. An AED generally functions as follows: two patches are affixed to the subject's chest and abdomen; the AED detects the heart rate and analyses the subject's heart condition using ECG electrodes integrated into the patches; and, if VF or VT are detected, the AED automatically delivers a high voltage and high energy electrical shock to the subject through the patches. This process differs from a standard defibrillator in which the high energy, high voltage shock is initiated by personnel operating the defibrillator. With an AED, the process of analyzing the heart condition and delivering of the shock is automated. The AED patches are adhered to the patient using a short-term adhesive since the patches are generally attached for not more than one hour. Further, since the patient has lost consciousness and is lying horizontally, the patches and adhesive are not designed for vertical adhesion or movement of the patient or for carrying the patch's weight.
Wearable Cardiac Defibrillators (WCD) differ from regular AEDs as WCDs are worn continuously by patients who are at high risk of sudden cardiac arrest (SCA) caused by VT or VF to provide continuous protection to the patient. Unless the VF is detected and defibrillation administered within a few seconds, VF and related SCA may cause sudden cardiac death (SCD). Patients who are at high risk for VF are candidates for an implantable cardioverter defibrillator (ICD). During the waiting period until the ICD implantation (in case such an implantation is not immediate), or in cases where the indication for ICD implantation is not sufficiently clear, a WCD is often used. The functionality provided by a WCD is thus similar to that of an ICD, but provided for a limited time period and without the need for an invasive implanting procedure.
WCDs usually include two types of patches/electrodes: sensing electrodes or patches and shocking electrode or patches. The sensing electrodes or patches are similar to standard ECG patches in function and are used to sense the ECG of the patient in order to detect VF. The defibrillation electrodes or patches are used to transmit a high voltage and high energy defibrillation shock to the patient's heart in a case of SCA. These shocks usually have a voltage in the range of 1000V-3000V and energy in the range of 150-300 Joules. In practice the voltage and energy to be delivered depends on the patient impedance, which is usually measured prior to shock delivery.
Some current WCDs consist of sensing patches and shocking electrode patches that are stuck onto the patient's skin using some form of adhesive. Since a wearable defibrillator must be used on a 24/7 basis and often for extended periods of time (several days and typically over one week), patches that are in contact with the patient's body via the adhesive may cause discomfort for the patient and skin irritations in some cases, and make it difficult to perform normal daily activities. The discomfort from the adhesive patches is therefore a function of both the time used and also the amount of activity.
To resolve the skin discomfort from adhesives, other current WCDs consist of a wearable vest/top where the sensing patches and shocking electrode patches are pressed against the patient's skin, usually by one or more tightening straps such as over-shoulder and torso straps. In order to sufficiently deliver the high energy defibrillation pulse, a good connection is required between the shocking electrode patches and the patient's skin. Since the patches in the vest are not stuck to the patient's body, they are held in tight direct contact with the patient's skin by the vest and also feature a gel release mechanism to enhance skin contact required during shock delivery. Tight vests force electrodes into contact with the patient's body, thus also causing major discomfort and making it difficult to perform normal daily activities. Additionally, the vest itself is in direct contact with the patient's skin and can also cause significant discomfort. Further the vest needs to be washed on a daily basis while active elements are removed and repositioned in a secondary vest, forcing the patient to ensure the repositioned active elements are placed correctly on a daily basis. In some known cases patients were not protected since the active elements were incorrectly positioned by the patient. Finally, such daily maintenance activity may not be appropriate for elderly patients or patients who need care or assistance.
Further, the defibrillation electrical elements (batteries, capacitors and electronic circuits) are usually provided in a box that must be worn, such as with a strap or clamp onto clothing, resulting in a cumbersome source of discomfort to the patient. These causes of discomfort (patches, vest, box) may result in the patient removing the vest or patches, thus causing compliance issues and potentially endangering the life of the patient.
Finally, although wearable defibrillators feature ECG patches attached to a patient, they generally do not make use of these for integration with a cardiac telemetry system. Cardiac telemetry is usually provided by devices such as Holter monitors or implantable recorder systems that feature ongoing heart monitoring.
Exemplary embodiments disclosed herein relate to a wearable automated Belt Cardiac Defibrillator (BCD) and method of use. The BCD as disclosed herein is adapted so as provide AED functionality and automated ease of use in a wearable form that is comfortable for long term use by a subject Improvements in comfort are provided by several innovations as described further herein:
In some other embodiments, a proposed BCD includes defibrillation electrodes and ECG sensors mounted in a flexible removable patch strip for adhesion to the patient or insertion into a stretchable, washable top.
Further, in some embodiments, the BCD as disclosed performs cardiac telemetry by continuously monitoring and analyzing the subject's heart using the ECG sensor and controller, and reporting detected arrhythmias to a patient's phone and/or to a remote monitoring center.
In some embodiments, a flexible automated wearable belt cardiac defibrillator (BCD) for wearing by a subject, comprises: at least two patches adapted for adhering to the subject each comprises a defibrillation electrode and at least one ECG sensor; and a BCD controller connected to each of the patches, wherein the patches comprise an adhesive adapted for long-term adhering of the patches to the subject, wherein the patches and adhesive are adapted for movement of the subject while the patches are adhered to the subject, wherein the patches are replaceable, wherein the controller is housed in a flexible belt comprises a plurality of compartments for wearing by the subject, wherein the controller is adapted for being flexible, and wherein the adaptation for being flexible comprises distributing the controller components between the plurality of compartments.
In some embodiments, the controller components comprise a battery, at least one high voltage and high energy capacitor, and controller electronics, and each of the controller components is housed in a separate one of the plurality of compartments. In some embodiments, the belt comprises a flexible material. In some embodiments, “long-term” is between one day and 10 days. In some embodiments, “long-term” may be even longer than 10 days. In some embodiments, the compartments have the form of pockets. In some embodiments, the patches comprise a gel for enhancing electrical contact. In some embodiments, the adhesive is a biocompatible adhesive.
In some embodiments, at least one of the patches comprises a vibration element. In some embodiments, the vibration element is adapted for vibrating to alert the subject prior to an impending shock delivery by the defibrillation electrode. In some embodiments, the weight of the controller components is distributed around the belt. In some embodiments, the patches are small patches having dimensions of less than 8×8 cm. In some embodiments, at least three patches for providing at least two defibrillation vectors. In some embodiments, the controller comprises a controller vibration pad.
In some embodiments, the controller vibration pad is adapted to generate vibration to alert the subject of an impending shock to be delivered by the defibrillation electrode. In some embodiments, the controller comprises an audio output device adapted to generate an alarm sound in case of an impending a shock about to be delivered by the defibrillation electrode. In some embodiments, the audio output device is adapted to sound an alarm following administering of a defibrillating shock. In some embodiments, the controller comprises a microphone adapted for recording the audio output of the subject.
In some embodiments, the controller is adapted for storage and/or analysis of ECG sensor data sensed by the ECG sensor. In some embodiments, the controller comprises an ECG event button and pressing the event button creates a time stamp in the collected ECG sensor data. In some embodiments, pressing of the ECG event button initiates recording via the microphone. In some embodiments, the controller is adapted to measure impedance between the patches and the body of the subject to determine the strength of the electrical connection therebetween. In some embodiments, the controller comprises an abort button adapted for aborting an impending shock from the defibrillation electrode. In some embodiments, the BCD further comprises a safety switch and the safety switch is adapted to electrically disconnect the controller from the defibrillation electrode.
In some embodiments, the controller comprises a controller motion sensor and/or the BCD comprises an ECG sensor motion sensor. In some embodiments, one or both of controller motion sensor and the ECG motion sensor are adapted for determining data related to movement of the subject. In some embodiments, the patches comprise multiple perforations throughout the patches. In some embodiments, the patches comprise connectors for connecting or disconnecting interconnection cables between the patches and/or between the patches and the controller.
In some embodiments, the controller is adapted for data communication with a remote monitoring center (RMC). In some embodiments, ECG data sensed by the ECG sensor is transmitted to the RMC for analysis and storage. In some embodiments, detected arrhythmia events are transmitted to the RMC. In some embodiments, the controller comprises a GPS receiver adapted for determining the geolocation of the BCD, wherein the determined location is transmitted to the RMC. In some embodiments, the controller comprises a microphone and an audio device and is adapted for initiating a voice call with the RMC.
In some embodiments, the controller is adapted for wireless communication with an external device. In some embodiments, the external device presents the status of the BCD using a display of the external device. In some embodiments, audible, visual and/or vibrating indication of an impending shock to be delivered by the defibrillator electrode is provided by the external device using display, audio, and/or vibrating functions of the external device. In some embodiments, the external device comprises an abort button for aborting an impending shock to be delivered by the defibrillator electrode. In some embodiments, the BCD is adapted to deliver high voltage temporary external percutaneous heart pacing via the patches following detection by the BCD of asystole after delivering a shock. In some embodiments, the pacing is ventricular demand pacing. In some embodiments, the pacing is provided at a rate of 35 BPM.
In some embodiments, the BCD functions without the need for any other part of the BCD to be in contact with the subject's skin other than the patches. In some embodiments, the controller is not attached to the subject via a patch touching the subject skin. In some embodiments, the patches include at least two ECG sensor electrodes for ECG sensing from at least one sensing vector. In some embodiments, the patches include electrodes delivering a high voltage and high energy defibrillation shock from at least one shocking vector.
In some embodiments, a method for usage of an BCD comprises: providing the BCD as described above; adhering of the patches to the subject; operating the BCD; and following completion of an operational period, positioning of the patches to alternative locations on the subject wherein each of the alternate locations represents an alternate shock vector.
In some embodiments, the alternate shock vector is selected from the list consisting of: a first shock vector comprises a first patch on a right side of the chest and a second patch on a left side of the abdomen, a second shock vector comprises the first patch on a left side of the chest and the second patch on a right side of the abdomen and a third shock vector comprises the first patch on an upper right side of the chest and the second patch on an upper left side of the back.
In some embodiments, the controller is adapted to indicate completion of the operational period for movement of the patches. In some embodiments, the external device is adapted to provide guided instructions for positioning of the patches.
In some embodiments, a BCD for wearing by a subject, comprises: a removable patch strip (RPS) comprising at least one defibrillation patch and at least one ECG sensor; and a top comprising a pocket for insertion of the RPS, such that the at least one defibrillation patch and the at least one ECG sensor are pressed against the torso of the subject. In some embodiments, the top comprises a stretchable material. In some embodiments, the top comprises a washable material.
As used herein, the terms “patch” or “pad” describe a patch incorporating one or both of a sensing electrode and a defibrillation electrode. The terms “patient” and “subject” are used herein interchangeably.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The materials, methods, and examples provided herein are illustrative only and not intended to be limiting.
Implementation of the method and system of the present disclosure may involve performing or completing certain selected tasks or steps manually, automatically, or a combination thereof. Moreover, according to actual instrumentation and equipment of preferred embodiments of the method and system of the present disclosure, several selected steps may be implemented by hardware (HW) or by software (SW) on any operating system of any firmware, or by a combination thereof. For example, as hardware, selected steps of the disclosure could be implemented as a chip or a circuit. As software or algorithm, selected steps of the disclosure could be implemented as a plurality of software instructions being executed by a computer using any suitable operating system. In any case, selected steps of the method and system of the disclosure could be described as being performed by a data processor, such as a computing platform for executing a plurality of instructions.
Although the present disclosure is described with regard to a “computing device”, a “computer”, or “mobile device”, it should be noted that optionally any device featuring a data processor and the ability to execute one or more instructions may be described as a computer, including but not limited to any type of personal computer (PC), a server, a distributed server, a virtual server, a cloud computing platform, a cellular telephone, an IP telephone, a smartphone, a smart watch or a PDA (personal digital assistant). Any two or more of such devices in communication with each other may optionally comprise a “network” or a “computer network”.
Aspects, embodiments and features disclosed herein will become apparent from the following detailed description when considered in conjunction with the accompanying drawings. Like elements may be marked with like numerals in different figures, where:
Exemplary embodiments disclosed herein relate to a wearable AED (BCD) and method of use.
As shown in the plan view of
In some embodiments, BCD 200 is adapted for use by a female subject. As shown in
Non-limiting examples of external device 422 are a smart watch or smartphone. External device 422 is in wireless communication with defibrillation patches 416, ECG sensors 418 and defibrillation controller 420. A non-limiting example of a wireless communication protocol is Bluetooth. External device 422 is a computing device and runs software to monitor the subject's heart using data received wirelessly from sensors 418, and triggers defibrillation patches 416 if required by communicating with controller 420 and/or defibrillation patches 416. In some embodiments, controller 420 is integrated into RPS 410 similarly to the way controller 320 is integrated into RPS 310.
In some embodiments, each of patches 510 includes include three or more ECG sensors 518 for sensing simultaneous sensing vectors. Multiple sensing electrodes per EC sensor 518 provides better sensing and detection of VF and discrimination of non-VF arrhythmias.
In some embodiments, each of patches 510 includes three or more defibrillation electrodes 516 for providing multiple simultaneous shock vectors. for better coverage of the heart and reduction of defibrillation threshold energy.
Patches 510A, 510B are affixed to the body of the subject using a biocompatible adhesive that is non-irritating for skin, is adapted both for extended use and for ensuring adhesion while that the subject continues to be active and mobile. A non-limiting example of a suitable adhesive may be KM40C by Katecho LLC of Des Moines, Iowa. In some embodiments, extended use covers a period of over 7 days. In some embodiments, extended use covers a period of over 10 days.
In some embodiments, patches 510A, 510B comprise gel for enhancing electrical contact. In some embodiments, defibrillation electrode 516 performs ECG signal measurement and ECG sensor 518 is not required.
In some embodiments, replaceable patches 510A, 510B include a vibration element 530 used to alert the patient prior to shock delivery. In some embodiments, replaceable patches 510A, 510B are replaced periodically. In some embodiments, replaceable patches 510A, 510B are disposable. In some embodiments, BCD 500 comprises more than two patches 510. Cables 522 provide electrical connectivity between patches 510 and cables 524 provide electrical connectivity between patches 510 and controller belt 520. As shown in
Controller belt 520 has the form of a flexible belt. Belt 528 comprises a flexible material. Controller belt 520 is flexible and wearable and comprises an adjustment means 542 such a belt adjustment means known in the art in order to fit controller belt 520 comfortably around the waist or torso of the subject. Alternatively, belt 520 may be worn on another part of the body or may be carried.
Controller belt 520 contains all the components of a defibrillator controller (such as controller 720, high voltage capacitors, batteries, electronics, high voltage shock circuits, alarm system, communication system, operating software as well as detection algorithm software) embedded in a flexible manner. In the form of a flexible belt, controller 520 is portable and well suited for comfortable wearing by a patient on a daily basis and may be shifted around the waist of the subject (or worn elsewhere) for comfort. As shown in
Wiring (not shown) between compartments 526 provides for the electrical connections between the components of controller 520. In some embodiments, compartments 526 are cylindrical in shape. In some embodiments, compartments 526 have the form of a pocket. In some embodiments, compartments 526 are rectangular in shape. In some embodiments, belt 520 is a lightweight belt. In some embodiments, belt 520 including the patches 526 and cables 524 weighs less than 500 g.
Cables 524 enables removal of controller belt 520 from the subject for placing proximal to the patient while patches 510 remain attached to the subject to enable, for example, sleeping. In some embodiments, cables 524 are extendable for placing controller belt 520 further away from the subject. In some embodiments, compartments 526 are attached to controller belt 520 using flexible spacers (not shown).
In some embodiments, replaceable patches 510A, 510B can be placed in alternate locations to eliminate skin damage which may occur due to long-term usage of the patch in one position. A method for overcoming skin irritations which may be caused by patches and adhesives is shown in
In
Alternating the sides for patches 510 enables use of relatively large patches compared to standard AED patches (desirable for conductivity) while reducing potential discomfort of subjects.
In the embodiment of
To enable sufficient energy to be conveyed by defibrillation electrodes 616 to the heart of a subject during a shock, more than two patches 610 are affixed to the subject. Multiple defibrillation electrodes 616 provide multiple shock vectors between the affixed defibrillation electrodes 616. As shown in
In some embodiments, patches 610 comprise gel for enhancing electrical contact. In some embodiments, replaceable patches 610 are replaced periodically. Cables 622 provide electrical connectivity between patches 610 via connectors 644 and cables 624 provide electrical connectivity between patches 610 (via connector 644) and controller belt 620 as described above with reference to
It should be appreciated that the components of controller 720 as described below may be provided in a single housing (such as but not limited to the housings of controllers 120 or 420) or alternatively may be distributed into multiple housings such as but not limited to the embodiment of
In some embodiments, the ECG sensors 718 and controller are adapted for sensing simultaneous sensing vectors. The adaptation includes sensing from three or more sensing electrodes placed on two or more patches for better sensing and detection of VF and discrimination of non-VF arrhythmias.
In some embodiments, defibrillation electrodes 716 are adapted for providing multiple simultaneous shock vectors. The adaptation includes providing three or more shock electrodes each placed on a patch 715 for better coverage of the heart and reduction of defibrillation threshold energy.
In some embodiments, controller 720 comprises an activation switch 728 to turn BCD 700 ON once the patches are in place. In some embodiments, controller 720 comprises an audio output device 726 to generate an alarm sound such as beeping or buzzing to alert the patient in case VT or VF was detected and a shock is about to be delivered. Additionally, audio device 726 may play audio messages from RMC 724, or messages related to the BCD 700 status. In some embodiments, controller 720 also comprises a microphone 730 for hearing comments from the subject. In some embodiments, audio output device 726 sounds an audible alarm following administering a defibrillating shock to warn/notify passers-by.
In some embodiments, ECG data as sensed by sensor patch 718 is collected for storage by controller 720, analysis by controller 720 and/or transmission to RMC 724 for analysis and storage. In some embodiments, controller 720 includes an ECG event button 752 for creating a time stamp in the collected ECG data such as but not limited to when a patient feels an arrythmia or other sensation the patient wishes to record. In some embodiments, ECG event button 752 initiates recording via microphone 730 such that the patient can state the reason for pressing ECG event button 752. In some embodiments, ECG data is continually buffered but only stored/recorded by controller 720 when ECG event button 752 is pressed including recording a time period before ECG event button 752 was pressed.
In some embodiments, controller 720 comprises visual indication means such as a display 732 and/or status lights 734 for displaying the status of BCD 700 and/or displaying messages related to BCD 700 and use thereof. In some embodiments, controller 720 measures impedance of patches 716, 718 to the body of the subject to determine the strength of the electrical connection therebetween. In some embodiments, controller 720 displays the measured strength of the electrical connection of a patch 716 and/or 718 to the skin of the subject. In some embodiments, controller 720 indicates the level of connection of patches 716 and/or 718 with the skin of the subject. In some embodiments, controller 720 indicates a suggested period for replacement or movement of patches 716, 718.
In some embodiments, controller 720 comprises a vibration device 736 to generate vibration to alert the patient in case VF was detected and a shock is about to be delivered. Additionally or alternatively, in some embodiments, a vibration alert is delivered to the subject via vibration patch 714.
In some embodiments, controller 720 comprises an abort button 738 used to abort a shock in a case the patient feels fine but the BCD 700 is alerting that a shock is about to be delivered. In some embodiments, controller 720 comprises an emergency call button 740. In some embodiments, safety switch 754 electrically disconnects controller 720 from defibrillation patch 716. In some embodiments, safety switch 754 is activated by abort button 738.
In some embodiments, controller 720 is in wireless communications with an RMC 724. In some embodiments, controller 720 notifies RMC 724 of an administered defibrillation shock. In some embodiments, controller 720 continuously analyzes the signal from ECG patch 718 to determine whether an arrhythmia has occurred. In some embodiments, detected arrhythmia events are stored by controller 720. In some embodiments, detected arrhythmia events are transmitted to RMC 724. In some embodiments, controller 720 comprises a GPS receiver 742, and the location of controller 720 is transmitted along with any information transmitted to RMC 724. In some embodiments, a patient can initiate a voice call with medical staff at the RMC 724 using microphone 730 and audio output 726.
In some embodiments, controller 720 includes a motion sensor 748. Motion sensor 748 may include one or more of a gravity sensor, linear acceleration sensor, rotation vector sensor, step counter, step detector, accelerometer and/or gyroscope. In some embodiments, sensor patch 718 includes a motion sensor 750. Motion sensor 750 may include one or more of a gravity sensor, linear acceleration sensor, rotation vector sensor, step counter, step detector, accelerometer and/or gyroscope. In some embodiments, one or both of motion sensors 748, and 750 may determine data related to movement of the patient. In some embodiments, movement data is collected by controller and combined with the ECG data provided sensor patch 718. In some embodiments, motion sensor data, indicative of the movement of the patient, is used as part of monitoring of syncope by controller 720 and/or by RMC 724.
In some embodiments, controller 720 comprises batteries 744 that can be replaceable and/or rechargeable. In some embodiments, rechargeable batteries 744 use either wireless charging or are charged using a cable (not shown) connected to the controllers from a power source.
In some embodiments, controller 720 is in wireless communication with external device 722. Non-limiting examples of external device 722 include a smartphone or smart watch. External device 722 comprises a software application (app) 746 for running on the external device. In some embodiments, app 746 presents the status of BCD 700 using the display of the external device such as, for example, to indicate a need for charging of BCD 700 or to indicate an error in the functioning of BCD 700. In some embodiments, the audible, visual and/or vibrating indication of an impending shock is provided by app 746 using the display, audio, and/or vibrating functions of external device 722. In some embodiments, an abort button is provided by app 746 and the touchscreen capability for activating the abort button is provided by external device 722. In some embodiments, an indication of the impending shock or activation of a shock is transmitted from controller 720 to external device 722 for further transmission by external device 722 using the built-in data communication functionality of external device 722 to a RMC 724, such as for emergency response. In some embodiments, app 746 provides BCD 700 status information. In some embodiments, app 746 provides guided instructions for patch placement and rotation. In some embodiments, data from ECG patch 718 is provided to app 746 for analyzing of the signal from ECG patch 718 to determine whether an arrhythmia has occurred. In some embodiments, detected arrhythmia events are stored by app 746 on device 722. In some embodiments, detected arrhythmia events are transmitted by app 746 to RMC 724 using the communication features of device 722. In some embodiments, event button 752 is activated via app 746.
In some embodiments, when BCD 700 detects asystole after delivering a shock, BCD 700 delivers high voltage temporary external percutaneous heart pacing via patches 716. In some embodiments, the pacing is ventricular demand pacing (VVI). In some embodiments, the pacing is provided at a rate of 35 BPM.
In some embodiments, each patch 716, 718 comprises multiple perforations throughout the patch allowing for breathing of the skin while the patch is applied.
In the claims or specification of the present application, unless otherwise stated, adjectives such as “substantially” and “about” modifying a condition or relationship characteristic of a feature or features of an embodiment, are understood to mean that the condition or characteristic is defined to within tolerances that are acceptable for operation of the embodiment for an application for which it is intended.
It should be understood that where the claims or specification refer to “a” or “an” element, such reference is not to be construed as there being only one of that element.
In the description and claims of the present application, each of the verbs, “comprise” “include” and “have”, and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of components, elements or parts of the subject or subjects of the verb.
While this disclosure describes a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of such embodiments may be made. The disclosure is to be understood as not limited by the specific embodiments described herein, but only by the scope of the appended claims.
This application is a 371 of international patent application PCT/IB2020/057988 filed Aug. 26, 2020, and claims the benefit of U.S. Provisional patent application No. 62/892,090 filed Aug. 27, 2019, which is incorporated herein by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/IB2020/057988 | 8/26/2020 | WO |
Number | Date | Country | |
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62892090 | Aug 2019 | US |