METABOLIC BASED PREDICTION METHOD FOR A SUCCESSFUL DEFIBRILLATION
20180008835 · 2018-01-11
Inventors
Cpc classification
A61N1/3987
HUMAN NECESSITIES
International classification
Abstract
A system employing an ECG monitor (40) and a defibrillation advisory controller (20). In operation, the ECG monitor (40) monitors a cardiac rhythm of a patient, and the defibrillation advisory controller (20) generates a defibrillation advisory based on a cardiac rhythm status and a metabolic cardiac status of the patient, and optionally further based on an electrical cardiac status of the patient. The controller (20) derives the cardiac rhythm status as monitored by ECG monitor (40), and the optional electrical cardiac status inclusive of the cardiac rhythm monitored by the ECG monitor (40), and derives the metabolic cardiac status exclusive of the cardiac rhythm monitored by the ECG monitor (40). The controller (20) may compute or receive metabolic cardiac data indicative of the metabolic cardiac status (e.g., incorporating or coupled to a user input device (50), a breath analyzer (60) and a blood analyzer (70)), and compares the metabolic cardiac data to a metabolic cardiac threshold (fixed or variable) and/or monitors a trend of the metabolic cardiac data to derive the metabolic cardiac status of the patient.
Claims
1. A system, comprising: an ECG monitor (40) operable to monitor a cardiac rhythm of a patient; and a defibrillation advisory controller (20) operable in electrical communication with the ECG monitor (40) to generate a defibrillation advisory based on a cardiac rhythm status and a metabolic cardiac status of the patient, wherein the defibrillation advisory controller (20) is operable to derive the cardiac rhythm status of the patient as monitored by the ECG monitor (40), and wherein the defibrillation advisory controller (20) is operable to derive the metabolic cardiac status of the patient exclusive of the cardiac rhythm monitored by the ECG monitor (40).
2. The system of claim 1, wherein the defibrillation advisory controller (20) generates the defibrillation advisory as a non-shocking defibrillation advisory responsive to at least one of: the cardiac rhythm status indicating a non-shockable electrical cardiac rhythm of the patient; and the metabolic cardiac status indicating a non-shockable metabolic cardiac state of the patient.
3. The system of claim 1, wherein the defibrillation advisory controller (20) generates the defibrillation shock advice as a shocking defibrillation advisory responsive to both: the cardiac rhythm status indicating a shockable cardiac rhythm of the patient; and the metabolic cardiac status indicating a shockable metabolic cardiac state of the patient.
4. The system of claim 1, wherein the defibrillation advisory controller (20) is further operable to derive an electrical cardiac status of the patient inclusive of the cardiac rhythm monitored by the ECG monitor (40); and wherein the defibrillation advisory controller (20) generates the defibrillation advisory based on the cardiac rhythm status, the metabolic cardiac status and the electrical cardiac status of the patient.
5. The system of claim 4, wherein the defibrillation advisory controller (20) generates the defibrillation advisory as a non-shocking defibrillation advisory responsive to at least one of: the cardiac rhythm status indicating a non-shockable electrical cardiac rhythm of the patient; the metabolic cardiac status indicating a non-shockable metabolic cardiac state of the patient; and the electrical cardiac status indicating a non-shockable electrical cardiac state of the patient.
6. The system of claim 4, wherein the defibrillation advisory controller (20) generates the defibrillation advisory as a shocking defibrillation advisory responsive to all of: the cardiac rhythm status indicating a shockable electrical cardiac rhythm of the patient; the metabolic cardiac status indicating a shockable metabolic cardiac state of the patient; and the electrical cardiac status indicating a shockable electrical cardiac state of the patient.
7. The system of claim 1, wherein the defibrillation advisory controller (20) is operable to receive metabolic cardiac data indicative of the metabolic cardiac status of the patient; and wherein the defibrillation advisory controller (20) compares the metabolic cardiac data to an aerobic metabolism threshold to derive the metabolic cardiac status of the patient.
8. The system of claim 1, wherein the defibrillation advisory controller (20) is operable to receive metabolic cardiac data indicative of the metabolic cardiac status of the patient; and wherein the defibrillation advisory controller (20) monitors a trend of the metabolic cardiac data to derive the metabolic cardiac status of the patient.
9. The system of claim 1, further comprising: an user input device (60) in electrical communication with the defibrillation advisory controller (20) to provide metabolic cardiac data indicative of the metabolic cardiac status of the patient to the defibrillation advisory controller (20) for deriving the metabolic cardiac status of the patient.
10. The system of claim 1, further comprising: a breath analyzer (70) operable to generate metabolic cardiac data indicative of the metabolic cardiac status of the patient derived from a breathing sample of the patient, wherein the defibrillation advisory controller (20) is operable in communication with the breath analyzer (70) to receive the metabolic cardiac data for deriving the metabolic cardiac status of the patient.
11. The system of claim 1, a blood analyzer (80) operable to generate metabolic cardiac data indicative of the metabolic cardiac status of the patient derived from a blood sample of the patient, wherein the defibrillation advisory controller (20) is operable in communication with a blood analyzer (80) to receive the metabolic cardiac data for deriving the metabolic cardiac status of the patient.
12. A defibrillation advisory controller (20), comprising: a cardiac rhythm analyzer (21) operable to derive a cardiac rhythm status of a patient; a metabolic cardiac analyzer (23) operable to derive a metabolic cardiac status of the patient exclusive of the cardiac rhythm of the patient; and a defibrillation advisor (24) operable in electrical communication with the electrical cardiac analyzer (21) and the metabolic cardiac analyzer (23) to generate a defibrillation advisory responsive to the cardiac rhythm status and the metabolic cardiac status of the patient.
13. The defibrillation advisory controller (20) of claim 12, wherein the defibrillation advisor (24) generates the defibrillation advisory as a non-shocking defibrillation advisory responsive to at least one of: the cardiac rhythm status indicating a non-shockable electrical cardiac rhythm of the patient; and the metabolic cardiac status indicating a non-shockable metabolic cardiac state of the patient; and wherein the defibrillation advisor (24) generates the defibrillation shock advice as a shocking defibrillation advisory responsive to both: the cardiac rhythm status indicating a shockable cardiac rhythm of the patient; and the metabolic cardiac status indicating a shockable metabolic cardiac state of the patient.
14. The defibrillation advisory controller (20) of claim 12, further comprising: an electrical activity analyzer (22) operable to further derive an electrical cardiac status of the patient inclusive of the cardiac rhythm of the patient, wherein the defibrillation advisor (24) is further operable in electrical communication with the electrical activity analyzer (22) to generate a defibrillation advisory responsive to the cardiac rhythm status, the metabolic cardiac status and the electrical cardiac status of the patient.
15. The defibrillation advisory controller (20) of claim 14, wherein the defibrillation advisor (24) generates the defibrillation advisory as a non-shocking defibrillation advisory responsive to at least one of: the cardiac rhythm status indicating a non-shockable electrical cardiac rhythm of the patient; the metabolic cardiac status indicating a non-shockable metabolic cardiac state of the patient; the electrical cardiac status indicating a non-shockable electrical cardiac state of the patient; and wherein the defibrillation advisor (24) generates the defibrillation shock advice as a shocking defibrillation advisory responsive to all of: the cardiac rhythm status indicating a shockable cardiac rhythm of the patient; and the metabolic cardiac status indicating a shockable metabolic cardiac state of the patient; and the electrical cardiac status indicating a shockable electrical cardiac state of the patient.
16. A defibrillation method, comprising: an ECG monitor (40) monitoring a cardiac rhythm of a patient; the defibrillation advisory controller (20) deriving a cardiac rhythm status of the patient as monitored by the ECG monitor (40); the defibrillation advisory controller (20) deriving a metabolic cardiac status of the patient exclusive of the cardiac rhythm monitored by the ECG monitor (40); and the defibrillation advisory controller (20) generating a defibrillation advisory based on the cardiac rhythm status and the metabolic cardiac status of the patient.
17. The method of claim 16, wherein the defibrillation advisory controller (20) generates the defibrillation advisory as a non-shocking defibrillation advisory responsive to at least one of: the cardiac rhythm status indicating a non-shockable electrical cardiac rhythm of the patient; and the metabolic cardiac status indicating a non-shockable metabolic cardiac state of the patient; and wherein the defibrillation advisory controller (20) generates the defibrillation shock advice as a shocking defibrillation advisory responsive to both: the cardiac rhythm status indicating a shockable cardiac rhythm of the patient; and the metabolic cardiac status indicating a shockable metabolic cardiac state of the patient.
18. The method of claim 16, further comprising: the defibrillation advisory controller (24) deriving an electrical cardiac status of the patient inclusive of the cardiac rhythm of the patient, wherein the defibrillation advisor (24) generates the defibrillation advisory based on the cardiac rhythm status, the metabolic cardiac status and the electrical cardiac status of the patient.
19. The method of claim 18, wherein the defibrillation advisory controller (20) generates the defibrillation advisory as a non-shocking defibrillation advisory responsive to at least one of: the cardiac rhythm status indicating a non-shockable electrical cardiac rhythm of the patient; the metabolic cardiac status indicating a non-shockable metabolic cardiac state of the patient; the electrical cardiac status indicating a non-shockable electrical cardiac state of the patient; and wherein the defibrillation advisory controller (20) generates the defibrillation shock advice as a shocking defibrillation advisory responsive to all of: the cardiac rhythm status indicating a shockable cardiac rhythm of the patient; and the metabolic cardiac status indicating a shockable metabolic cardiac state of the patient; and the electrical cardiac status indicating a shockable electrical cardiac state of the patient.
20. The method of claim 16, further comprising: the defibrillation advisory controller (20) having metabolic cardiac data indicative of the metabolic cardiac status of the patient; and wherein to derive the metabolic cardiac status of the patient, the defibrillation advisory controller (20) at least one of compares the metabolic cardiac data to an aerobic metabolism threshold and monitors a trend of the metabolic cardiac data.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0025]
[0026]
[0027]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] To facilitate an understanding of the present invention, the following description of
[0029] Of importance to note is the exemplary description herein is directed to an incorporation of an electrical cardiac status with a cardiac rhythm status and a metabolic cardiac status for a complete exemplary description. Nonetheless, in practice, the electrical cardiac status may be omitted for defibrillation advisory purposes.
[0030] Also of importance to note is various components are illustrated and described herein as separate and distinct components for clarity in describing the components. Nonetheless, in practice, such components may be housed in the same device and even further implemented by the same hardware and/or within the same software/firmware.
[0031] Referring to
[0032] Specifically, process stage S12A encompasses a cardiac rhythm analysis derived from ECG data as known in the art and resulting in a cardiac rhythm status CRS indicator of (1) a shockable cardiac rhythm (e.g. VF or VT) of the ECG signal or (2) a non-shockable cardiac rhythm (e.g., asystole) of the ECG signal.
[0033] Process stage S12B encompasses an electrical cardiac analysis derived from ECG data as known in the art and resulting in an electrical cardiac status ECS indicator of (1) electrical activity of the ECG signal likely to support a return of spontaneous circulation (“ROSC”) or (2) electrical activity of the ECG signal, if any, unlikely to support ROSC. Examples of predictive features of electrical activity within the ECG signal electrical activity as known in the art include, but are not limited to, amplitude range, average P-P amplitude, mean amplitude, amplitude spectrum analysis, peak frequency, centroid frequency, spectral flatness measure, energy, maximum power, centroid power, power spectrum analysis, mean slope and median slope.
[0034] Process stage S12C encompasses a metabolic cardiac analysis derived from metabolic cardiac data MCD independent of the ECG signal and resulting in a metabolic cardiac status MCS indicator of (1) cardiac aerobic metabolism likely to support ROSC, or (2) cardiac aerobic metabolism, if any, unlikely to support ROSC. Examples of predictive metabolic cardiac data include, but are not limited to, end-tidal carbon dioxide CO.sub.2, and lactate and pH concentration in blood.
[0035] Decision stage S14 encompasses a decision whether or not a defibrillation shock should be delivered to the patient based on a combination of cardiac rhythm status CRS, electrical cardiac status ECS and metabolic cardiac state MCS and results in a defibrillation advisory DA of (1) a decision to recommend shock delivery decision or a (2) a decision not to recommend shock delivery. More particularly, if the ECG signal indicates a shockable cardiac rhythm and support for ROSC AND the metabolic cardiac data MCD independent of the ECG signal also supports ROSC, the combination of statuses provides a prediction for a successful defibrillation that results in a decision to recommend shock delivery. Otherwise, if the ECG signal indicates a non-shockable cardiac rhythm and/or fails to support ROSC OR the metabolic cardiac data MCD independent of the ECG signal also fails to support ROSC, the combination of statuses provides a prediction of an unsuccessful defibrillation that results is a decision not to recommend shock delivery.
[0036] A process stage S16 of flowchart 10 encompasses a communication of defibrillation advisory DA that may include, but is not limited to, a textual/graphical display (particularly in conjunction with an ECG display), an audible message, and a visual indication of a charging or non-charging of a shock source. A reaction to a communication ranges from an acknowledgment that a shock will likely restore a pulsatile rhythm (i.e., shock delivery) to the initiation or continuation of chest compressions or termination of resuscitation efforts (i.e., non-shock delivery).
[0037] Process stage S16 returns to stages S12A-S12C until termination of flowchart 10.
[0038] To further facilitate an understanding of the present invention, the following description of
[0039] Referring to
[0040] Cardiac rhythm analyzer 21 executes known techniques for analyzing ECG data (
[0041] Electrical cardiac analyzer 22 analyzes predictive features of ECG data (
[0042] In one embodiment, electrical cardiac analyzer 23 compares an instantaneous measurement of a predictive feature to an electrical activity threshold whereby the predictive feature exceeding the electrical activity threshold as symbolically shown indicates support for ROSC and whereby the predictive feature being less than the electrical activity threshold as symbolically shown fails to indicate support for ROSC.
[0043] For example, an amplitude spectrum analysis (“AMSA”) of the ECG data may be compared to an electrical activity threshold of 1.75.
[0044] Alternatively, the predictive feature exceeding the electrical activity threshold fails to indicate support for ROSC, and the predictive feature being less than the electrical activity threshold indicates support for ROSC.
[0045] In practice, the electrical activity threshold for each predictive feature should be chosen to balance sensitivity (aggressive defibrillation) versus specificity (aggressive compression), and may be fixed or variable.
[0046] Also in practice, a combination of multiple predictive features may be analyzed for determining support or non-support of ROSC. For such combinations, the predictive features may or may not be equally weighted.
[0047] In another embodiment, electrical cardiac analyzer 22 analyzes a trend of a predictive feature as symbolically shown whereby an upward trend of the predictive feature as symbolically shown indicates support for ROSC and whereby a downward trend of the predictive feature as symbolically shown fails to indicate support for ROSC.
[0048] Alternatively, an upward trend but low value of the predictive feature can indicate a delay in recommending a shock to allow additional recovery would better support ROSC, and a downward trend with a high value of the predictive feature indicates recommending an early shock would give better support for ROSC.
[0049] In practice, the conditions for determining a trend should be chosen to balance sensitivity (aggressive defibrillation) versus specificity (aggressive compressions).
[0050] Again in practice, a combination of multiple predictive features may be analyzed for determining support or non-support of ROSC. For such combinations, the predictive features may or may not be equally weighted.
[0051] Metabolic cardiac analyzer 23 analyzes predictive features of metabolic cardiac data MCD (
[0052] In one embodiment, metabolic cardiac analyzer 23 compares an instantaneous measurement of a predictive feature to an aerobic metabolism threshold whereby the predictive feature exceeding the aerobic metabolism threshold as symbolically shown indicates support for ROSC and whereby the predictive feature being less than the aerobic metabolism threshold as symbolically shown fails to indicate support for ROSC.
[0053] For example, a partial pressure of end-tidal CO.sub.2 may be compared to an aerobic metabolism threshold of 10 mmHg.
[0054] Alternatively, the predictive feature exceeding the aerobic metabolism threshold fails to indicate support for ROSC, and the predictive feature being less than the metabolic threshold indicates support for ROSC.
[0055] In practice, the aerobic metabolism threshold for each predictive feature should be chosen to balance sensitivity (aggressive defibrillation) versus specificity (aggressive compression), and may be fixed or variable.
[0056] Also in practice, a combination of multiple predictive features may be analyzed for determining support or non-support of ROSC. For such combinations, the predictive features may or may not be equally weighted.
[0057] In another embodiment, metabolic cardiac analyzer 23 analyzes a trend of a predictive feature as symbolically shown whereby an upward trend of the predictive feature as symbolically shown indicates support for ROSC and whereby a downward trend of the predictive feature as symbolically shown fails to indicate support for ROSC.
[0058] Alternatively, an upward trend but low value of the predictive feature can indicate a delay in recommending a shock to allow additional recovery would better support ROSC, and a downward trend with a high value of the predictive feature indicates recommending an early shock would give better support for ROSC.
[0059] In practice, the conditions for determining a trend should be chosen to balance sensitivity (aggressive defibrillation) versus specificity (aggressive compression).
[0060] Again in practice, a combination of multiple predictive features may be analyzed for determining support or non-support of ROSC. For such combinations, the predictive features may or may not be equally weighted.
[0061] Defibrillator advisor 24 combines signals from analyzers 21-23 to decide whether to communicate defibrillation advisory DA as (1) a shocking delivery decision or (2) a non-shocking delivery decision.
[0062] In practice, signals from analyzers 21-23 may be combined by defibrillator advisor 24 in any manner determined to yield a successful prediction for a defibrillation.
[0063] In one embodiment, defibrillator advisor 24 applies a logical chart 25a whereby each signal from analyzer 21-23 is utilized as an input signal.
[0064] For this embodiment, if (1) cardiac rhythm analyzer 21 outputs a non-shocking cardiac rhythm NCR or (2) electrical cardiac analyzer 22 outputs a non-shocking electrical cardiac state NECS or (3) metabolic cardiac analyzer 23 outputs a non-shocking metabolic cardiac state NMCS, then defibrillator advisor 24 communicates the defibrillation advisory DA as a non-shocking defibrillation advisory NDA.
[0065] Otherwise, if (1) cardiac rhythm analyzer 21 outputs a shocking cardiac rhythm CCR and (2) electrical cardiac analyzer 22 outputs a hocking electrical cardiac state SECS and (3) metabolic cardiac analyzer 23 outputs a shocking metabolic cardiac state SMCS, then defibrillator advisor 24 communicates the defibrillation advisory DA as a shocking defibrillation advisory SDA.
[0066] In another embodiment, defibrillator advisor 24 applies a logical chart 25b whereby the signal from cardiac rhythm analyzer 21 is used as an enabling signal for electrical cardiac analyzer 22.
[0067] For this embodiment, if cardiac rhythm analyzer 21 outputs a non-shocking cardiac rhythm NCR, then electrical cardiac analyzer 22 is disabled and automatically outputs a non-shocking electrical cardiac state NECS, which results in defibrillator advisor 24 communicates the defibrillation advisory DA as a non-shocking defibrillation advisory NDA.
[0068] Otherwise, if cardiac rhythm analyzer 21 outputs a shocking cardiac rhythm SCR, then electrical cardiac analyzer 22 is enabled whereby defibrillator advisor 24 communicates the defibrillation advisory DA as a non-shocking defibrillation advisory NDA if (1) electrical cardiac analyzer 22 outputs a non-shocking electrical cardiac state NECS or (2) metabolic cardiac analyzer 23 outputs a non-shocking metabolic cardiac state NMCS, or whereby defibrillator advisor 24 communicates the defibrillation advisory DA as a shocking defibrillation advisory SDA if (1) electrical cardiac analyzer 22 outputs a shocking electrical cardiac state SECS and (2) metabolic cardiac analyzer 23 outputs shocking metabolic cardiac state SMCS.
[0069] To even further facilitate an understanding of the present invention, the following description of
[0070] Referring to
[0071] An ECG analyzing partition of defibrillation advisory controller 20 as shown in
[0072] A metabolic analyzing partition of defibrillation advisory controller 20 as shown in
[0073] Referring to
[0074] ECG monitor 40 is structurally configured as known in the art to measure an ECG waveform of heart 31 of patient 30 as an indication patient 30 is experiencing a shockable cardiac rhythm SCR (e.g., VF or VT) or a non-shockable cardiac rhythm NCR (e.g., asystole or normal sinus rhythm).
[0075] In one embodiment, ECG monitor 40 employs a digital signal processor (not shown) for streaming ECG data to defibrillation advisory controller 20 for analysis by cardiac rhythm analyzer 21 and electrical cardiac analyzer 22.
[0076] Shock source 50 is structurally configured as known in the art to store electric energy for delivery of a defibrillation shock 51 via electrode pads/paddles 52 to heart 31 of patient 30 as controlled by defibrillation advisory controller 25. In practice, defibrillation shock 51 may have any waveform as known in the art. Examples of such waveforms include, but are not limited to, a monophasic damped sinusoidal waveform (positive sine wave) 51a and a biphasic truncated exponential waveform 51b as shown in
[0077] In one embodiment, shock source 50 employs a high voltage capacitance (not shown) for storing a high voltage via a high voltage charger and a power supply upon a pressing of a charge button. Shock source 50 further employs a switching/isolation circuit (not shown) for selectively applying a specific waveform of an electric energy charge from the high voltage capacitance to electrode pads/paddles 52.
[0078] Referring to
[0079] Referring to
[0080] In one embodiment, defibrillation advisory controller 20 may be a separate modular component within a medical system from ECG monitor 40, shock source 50, breath analyzer 70 and blood analyzer 80 as shown in
[0081] In a second embodiment, defibrillation advisory controller 20 and ECG monitor may be incorporated within the same medical device that may or may not be a component of a medical system (e.g., an automated external defibrillator).
[0082] In a third embodiment, defibrillation advisory controller 20 and shock source 50 may be incorporated within the same medical device that may or may not be a component of a medical system (e.g., an automated external defibrillator).
[0083] In a fourth embodiment, breath analyzer 70 and/or blood analyzer 80 may or may not be integrated into defibrillation advisory controller 20, or may be incorporated with defibrillation advisory controller 20 within a master controller.
[0084] Referring to
[0085] Furthermore, as one having ordinary skill in the art will appreciate in view of the teachings provided herein, features, elements, components, etc. described in the present disclosure/specification and/or depicted in the
[0086] Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (e.g., any elements developed that can perform the same or substantially similar function, regardless of structure). Thus, for example, it will be appreciated by one having ordinary skill in the art in view of the teachings provided herein that any block diagrams presented herein can represent conceptual views of illustrative system components and/or circuitry embodying the principles of the invention. Similarly, one having ordinary skill in the art should appreciate in view of the teachings provided herein that any flow charts, flow diagrams and the like can represent various processes which can be substantially represented in computer readable storage media and so executed by a computer, processor or other device with processing capabilities, whether or not such computer or processor is explicitly shown.
[0087] Furthermore, exemplary embodiments of the present invention can take the form of a computer program product or application module accessible from a computer-usable and/or computer-readable storage medium providing program code and/or instructions for use by or in connection with, e.g., a computer or any instruction execution system. In accordance with the present disclosure, a computer-usable or computer readable storage medium can be any apparatus that can, e.g., include, store, communicate, propagate or transport the program for use by or in connection with the instruction execution system, apparatus or device. Such exemplary medium can be, e.g., an electronic, magnetic, optical, electromagnetic, infrared or semiconductor system (or apparatus or device) or a propagation medium. Examples of a computer-readable medium include, e.g., a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), flash (drive), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read/write (CD-R/W) and DVD. Further, it should be understood that any new computer-readable medium which may hereafter be developed should also be considered as computer-readable medium as may be used or referred to in accordance with exemplary embodiments of the present invention and disclosure.
[0088] Having described preferred and exemplary embodiments of novel and inventive system and method for predicting a successful defibrillation, (which embodiments are intended to be illustrative and not limiting), it is noted that modifications and variations can be made by persons having ordinary skill in the art in light of the teachings provided herein, including the
[0089] Moreover, it is contemplated that corresponding and/or related systems incorporating and/or implementing the device or such as may be used/implemented in a device in accordance with the present disclosure are also contemplated and considered to be within the scope of the present invention. Further, corresponding and/or related method for manufacturing and/or using a device and/or system in accordance with the present disclosure are also contemplated and considered to be within the scope of the present invention.