JP2008508976A - An external defibrillator for delivering defibrillation shocks based on electrocardiogram signals acquired prior to performing cardiopulmonary resuscitation - Google Patents

Abstract

A defibrillator with a pair of electrodes and method for delivering an artifact compensated defibrillation shock is provided. Electrocardiogram (ECG) data representing the ECG signal is acquired for the patient and the ECG data is analyzed to determine whether a defibrillation shock is appropriate. The cardiopulmonary resuscitation (CPR) period begins after ECG data acquisition. Upon completion of the CPR period, if the ECG data determines that a defibrillation shock is appropriate, the patient is provided with an AED to deliver the defibrillation shock.

Description

  The present invention is intended to quickly deliver a defibrillation pulse to a device used in electrotherapy, with minimal delay following a period of cardio-pulmonary resuscitation (CPR) performed specifically on a patient. It relates to a defibrillator.

  Medical device manufacturers have developed automatic electronic defibrillators (AEDs) to provide early defibrillation. AED applies high amplitude current pulses, waveforms or shocks to the heart to restore the patient's heart rhythm to normal levels. For example, FIG. 1 depicts a conventional AED 6 being applied to a cardiac arrest patient 2 by a rescuer 4. As shown in FIG. 1, a pair of defibrillation electrodes 8 are placed in the anterior-anterior (AA) position of the patient's torso to deliver a shock. To bring the patient back from cardiac arrest, it is often necessary to perform cardiopulmonary resuscitation (CPR) on the patient alternating with defibrillation shocks.

  When treating cardiac arrest patients with a defibrillator, it is important that the treatment be performed very quickly. This is because the probability of survival from cardiac arrest decreases dramatically with time after cardiac arrest. Thus, a quick response to cardiac arrest, in which the first defibrillation shock is performed from the beginning of the arrest, is important. Also, when pre-CPR chest compressions are performed at the rescue site to increase the chances of survival, survival will occur if there is a long interval between CPR breaks and shock delivery for patients experiencing ventricular fibrillation. The possibility of is significantly reduced. Thus, it is critical to shorten the process of analyzing cardiac rhythm before or immediately after the interruption of CPR to quickly prepare the AED for subsequent defibrillation shocks.

  Thus, the present invention is simple to use and allows a minimally trained user to easily, quickly and efficiently deploy a defibrillator to treat a patient while providing for chest compressions. An improved defibrillator is provided that reduces the time interval between delivery of defibrillation shocks.

  The present invention is directed to a method and system for applying a defibrillation shock to a patient with sudden cardiac arrest quickly and accurately, particularly following the application of pre-CPR chest compressions.

  According to one aspect of the invention, the delay between performing CPR and delivering a defibrillation shock is minimized by quickly distinguishing the end of the CPR period and charging the defibrillator.

  According to another aspect of the present invention, there is provided a method for applying electrotherapy in an automatic external defibrillator (AED) of the type having a high voltage energy source, an ECG detector, and a CPR therapy module. Is done. This method provides an indication of CPR cessation in order to have an AED for subsequent electrotherapy shocks. AED charging can be initiated prior to the end of the CPR therapy period, or can be completed prior to the end of the CPR therapy period. The method further includes obtaining an ECG signal from the ECG detector prior to the end of the CPR therapy period and determining whether the ECG signal is impaired by CPR activity.

  According to another aspect of the present invention, a defibrillator having a CPR delivery system is provided. It includes: a detector configured to detect a signal indicative of CPR pause; an energy source for providing defibrillation shock energy; a charging circuit for charging the energy source; and reacting to the signal And a controller for controlling the charging circuit. The interval between CPR pause and defibrillator charging for defibrillation shock delivery is less than about 10 seconds. The defibrillator further includes an ECG detector for detecting an ECG rhythm signal, whereby the processor activates the defibrillator in response to detecting a shocking ECG rhythm. Can be charged.

  According to yet another aspect of the invention, an apparatus for delivering a defibrillation shock to a patient is provided. The apparatus includes at least one sensor adapted to contact a patient; a detector coupled to a sensor for detecting an input signal indicative of disturbance associated with the application of cardiopulmonary resuscitation; input from a detection system Receive the signal and analyze the detected input signal to generate a signal that indicates that the electrocardiogram (ECG) signal from the patient is compromised and determine if a defibrillation shock is needed A processor for delivering; and a discharger for providing a defibrillation shock to the patient. The apparatus further includes an ECG front end coupled to the electrode pair to determine the patient's impedance, an LCD display and a speaker that notifies the operator prior to discharging the defibrillation shock.

  Yet another aspect of the present invention provides a method for delivering a defibrillation shock to a patient using a defibrillator. The method charges the defibrillator prior to the end of the cardiopulmonary resuscitation (CPR) period; analyzes the ECG signal prior to the end of the cardiopulmonary resuscitation (CPR) period; the signal associated with performing the CPR must be impaired Including defibrillation shock after cardiopulmonary resuscitation (CPR).

  Another aspect of the invention provides a method for delivering a defibrillation shock to a patient from a defibrillator. The method includes obtaining ECG data representing an ECG signal for the patient and analyzing the ECG data to determine whether defibrillation shock delivery is appropriate. The CPR period begins after the acquisition of ECG data. In response to the completion of the CPR period, if the ECG data determines that a defibrillation shock is appropriate, an AED is prepared to deliver the defibrillation shock to the patient.

  In order to facilitate understanding of the present invention, a conventional method of providing resuscitation is described.

  During the course of patient resuscitation in sudden cardiac arrest, the procedure followed by the rescuer is often the application of a defibrillation shock from an automatic electronic defibrillator (AED) and blood circulation until normal circulation is reestablished Seek administration of cardiopulmonary resuscitation (CPR) for various periods to promote In many cases, the resuscitation procedure is directed to the rescuer by issuing a voice prompt via the AED. For example, patients with cardiac arrest due to ventricular fibrillation may receive several pre-programmed periods of CPR following several defibrillation shocks. During CPR, the rescuer gives the patient chest compressions with breathing assistance.

  One of ordinary skill in the art will recognize that precordial compression during CPR is believed to provide artificial circulation, thereby increasing the patient's chances of survival. Following a pre-chest compression for a given period, the operator typically stops CPR so that the AED can analyze the patient's ECG rhythm to determine if further shock is needed. Prompted. However, it has been discovered that as the time interval between cessation of compression and delivery of defibrillation shocks increases, the likelihood of survival decreases rapidly. It is therefore important to minimize this critical interval as much as possible, preferably to less than 10 seconds.

  In conventional systems, following the CPR period, four steps need to be performed before the AED can deliver a shock: (1) The specified CPR time period set by the rescue procedure must pass (typically 1 to 3 minutes); (2) The patient's ECG rhythm needs to be analyzed to determine if the rhythm should be shocked; (3) The AED fully charges its energy storage capacitor (4) AED needs to be prepared to deliver a shock.

  Accompanying these steps, the AED typically issues a voice prompt to inform the operator not to touch the patient at the end of the CPR sequence. This can interfere with and thus delay the analysis of the patient's ECG rhythm. Following AED analysis and shock preparation, the operator often does not touch the patient (if the device is semi-automatic) and applies a shock by pressing the shock button, or (the AED is fully automatic). If so, you will be warned again to warn you that the shock will be delivered.

  In most prior art devices, the above four steps proceed as a series of sequences, resulting in a typical interval of 15 to 30 seconds between precordial compression and possible patient shock delivery. Occurs. In some cases, prior art devices partially charge the AED energy storage capacitor prior to completing the ECG analysis to save some time, but do not fully charge until the analysis is complete. Some prior art AEDs use artifact detection during an attempt to analyze a patient's ECG signal to determine if a shock should be delivered. Artifact detection is to obtain a disturbance signal, which can be derived from patient movement or any other possible source of ECG disturbance (eg, electromagnetic). The detected artifact is compared to the patient's ECG, eg, by cross-correlation, to determine if the disturbance was manifested by the ECG being compromised. Such damage will make the ECG analysis for shock advisory purposes unreliable. This is because ECG is known to contain signals that are not of cardiac origin. In general, these artifact detection systems have been used to prohibit analysis of damaged or potentially damaged ECG signals and to prompt the operator to remove the source of interference.

  Furthermore, prior art defibrillators have presented a risk of shock to the rescuer because they cannot detect whether the rescuer was in physical contact with the patient. One way in the prior art to address this problem is to provide a “contactless” period prior to the delivery of therapeutic shock. However, this delay is a defibrillation that is essential to increase the chances of surviving cardiac arrest by extending the interval between pre-CPR chest compressions, if required, and the delivery of defibrillation shocks. This is undesirable as it will prevent a quick response in the execution of the dynamic shock.

  In contrast, in a defibrillation system provided by an embodiment of the present invention, the application of electrotherapy shock is to detect a treatable arrhythmia via ECG analysis and to suspend or absent CPR pre-chest compression. Triggered by combination with detection. According to this embodiment, the defibrillation system shortens the time interval between precordial compression and subsequent defibrillation shock delivery.

  FIG. 2 is a simplified block diagram of a defibrillator 20 according to this embodiment of the invention. The defibrillator 20 includes a mechanical disturbance detector 10, an electrocardiogram (ECG) front end 32, a timer 34, a defibrillation operation / stop button 36, a high voltage (HV) switch 38, a processor 40, an audio circuit and a speaker 41. , Display 42, energy storage capacitor network 44, voltage charger 46 and battery 48. With reference to the system block diagram of FIG. 2, it is understood that in the following description, it is contemplated that the apparatus and method according to embodiments of the present invention may be used with other hardware configurations of a placement board. Shall be kept. In addition, it should be noted that any number of commercially available or commonly available defibrillators configured to generate defibrillation shocks may be utilized in various implementations based on preferred embodiments of the present invention. Will.

  As shown in FIG. 2, the mechanical disturbance detector 10 is connected to a sensor 12. The sensor is attached to the patient to detect patient movement during the application of pre-CPR chest compressions. Patient motion that may impair accurate evaluation of the signal of interest is detected and forwarded to the processor 40. Similarly, ECG front end 32 is connected to electrodes 22 and 24. The electrodes are attached to the patient to amplify, filter and digitize (using an analog-to-digital converter) the electrical ECG signal generated by the patient's heart. Upon receiving the detected ECG sample values, the processor 40 runs a shock advisory algorithm to detect rhythms that may deliver VF or other shocks that require treatment with a defibrillation shock. The ECG front end 32 may also measure the patient impedance between the electrodes 22 and 24 using a low level test signal. The low level test signal is a non-therapeutic pulse for measuring the voltage drop between the electrodes 22 and 24. In an alternative embodiment, the functions of the mechanical disturbance detector 10 and the ECG front end 32 can be merged as one component. Then, one of the electrodes connected to the ECG front end 32 can serve as a sensor for detecting patient movement.

  The HV switch 38 is configured to sequentially apply defibrillation pulses between the electrode pairs 22 and 24 to the patient with the desired polarity and duration. In a preferred embodiment, the HV switch 38 can be adapted to provide single polarity (monophasic), positive / negative bipolar (biphasic) or multiple positive / negative polarity (multiphasic). The timer 34 is connected to the processor 40 to provide a defibrillation pulse duration or duration when applying a defibrillation pulse between the electrode pairs 22 and 24. The activation / deactivation button 36 is connected to the processor 40 and allows the user to activate / deactivate defibrillation pulses between the electrodes 22 and 24 when a VF or other shocking rhythm is detected. To be able to stop. Note that the enable / disable button 36 can function in both AED mode and manual mode in the preferred embodiment. The voice circuit / speaker 41 provides voice instructions to the user during operation of the defibrillator 20. Alternatively, in other embodiments, such as a fully automatic AED, the activation / deactivation button may be omitted. The display 42 connected to the processor 40 is preferably a liquid crystal display (LCD) and provides visual feedback to the user. A battery 48 provides power for the defibrillator 20, particularly for the charger 46. The charger 46 charges the capacitors in the energy storage capacitor network 44. The energy storage capacitor network 44 includes a plurality of capacitors and resistors arranged in a series or parallel arrangement or a combination of series and parallel arrangements to provide a plurality of voltage level outputs between the electrodes 22 and 24. It will be apparent to those skilled in the art that a variety of RC arrangements can be implemented to produce different defibrillation pulse characteristics.

  In operation, electrodes 22 and 24 connected to the ECG front end 32 are attached to the patient to obtain patient impedance. The defibrillation pulses applied to the patient may be at a fixed level or may be several defibrillation pulses at different energy levels. This is accomplished by selecting an appropriate voltage level for the energy storage capacitor network 44 from the set of coordinations in order to deliver the desired impedance compensated defibrillation pulse to the patient.

  When the rescuer performs chest compressions as part of performing CPR on the patient, the resulting chest movement tends to disturb the electrodes attached to the chest region. Electrode movement on the chest skin area is undesirable for ECG signal detection because it creates interfering electrical noise or artifacts that can impair the ECG signal. Nevertheless, as will be discussed in detail later, artifacts in ECG signals are attributed to cardiopulmonary resuscitation (CPR) operations, whether artifacts caused by sensor mechanical disturbances, electromagnetic interference, or other environmental conditions Any artifact caused by movement is useful as an indicator that CPR is being performed when CPR is terminated and when the patient is being treated. In some embodiments, an accelerometer or other motion sensor can be included for such detection purposes. The defibrillator 20 is also provided with a display 42 for visually indicating a shock notice. Alternatively, an audio circuit and speaker may be provided to provide an audible announcement immediately prior to delivering a defibrillation shock.

  During a rescue attempt, if additional mechanical disturbances and / or artifacts are detected after the AED prepares for a shock, a defibrillation motion / stop 36 is provided. This is to cancel the shock within a short delay period prior to treatment. Alternatively, new mechanical disturbances and / or artifact movements can be automatically detected to cause cancellation or delay of defibrillation shock therapy.

  FIG. 3 is a detailed description of the components that allow for rapid analysis during mechanical disturbances. This makes it possible to perform arrhythmia discrimination using ECG without artifacts, particularly after a mechanical disturbance pause. Note that artifact detection can be performed in a variety of ways. For example, signal processing and processed signal correlation according to the present invention are described in US Patent Application No. 6,287,328, filed by the applicant and entitled "Multivariable Artifact Assessment", issued September 11, 2001. Various embodiments may be included. That teaching is hereby incorporated by reference.

  Briefly, an input signal indicative of patient movement is received via sensor 12 and provided to measurement circuit 10. The signal is then sent to signal processor 52 and forwarded to correlator 60 for correlation with the patient's ECG signal. The correlated signal is sent to the processor 40. As will be appreciated by those skilled in the art, suitable signal processing includes, for example, bandpass filters, Fourier transforms, wavelet transforms, time domain analysis, or joint time-frequency spectrograms. It is. Furthermore, the method for correlating data may be any correlation method known in the art. For example, correlation methods include individual and general cross-correlation techniques, including any process that efficiently correlates data with known mathematical functions. Individual implementations include, but are not limited to, finite sampled or continuous estimates of cross-covariance and cross-correlation, both biased and unbiased. Alternatively, the correlation may perform a similarity comparison between any multiple signals.

  Meanwhile, an input signal indicative of patient voltage and impedance is received between electrodes 22 and 24 and transmitted to differential mode amplifier 56 and common mode amplifier 62. Prior to the signal being sent to the signal processor, the signal is amplified by these amplifiers. The resulting signal is then transmitted to the respective signal processors 58 and 64 and processed to emphasize particular features. Specifically, the signal processor 58 provides signal information for correlation with variables including common mode signals, impedance signals or motion signals from the respective processors. The resulting processed signal is then transmitted to correlator 66, which correlates the signals. At the same time, the input signal is sent to an impedance detector 68 that provides an interelectrode impedance signal to the signal processor 70. The signal processor 70 processes the signal from the impedance detector 68 to emphasize certain features of the signal. The resulting processed signal is then transmitted to the correlator 72. Correlator 72 correlates the processed signal from signal processor 70 and differential amplifier 58. Once the signals are correlated in each correlator 66, 72, the resulting signal is sent to the processor 40. The processor 40 then evaluates the results of the correlators 66 and 72 and provides an indication of the degree to which the ECG signal of interest has been corrupted. The processor 40 finally provides an output signal. The output signal can be further analyzed as discussed below in connection with FIG.

  FIG. 4 is a flow chart illustrating the operational steps for applying an artifact compensated defibrillation shock according to a preferred embodiment of the present invention.

  Initially, the defibrillator 20 is deployed by attaching the sensor 12 and electrodes 22, 24 to the heart patient in order to analyze the patient input signal. Note that it is common to perform CPR on the patient, including precordial compression, along with the use of a defibrillator during a rescue attempt. Thus, as a possibility, the ongoing CPR is detected by the input signal from the sensor 12.

  In step 100, the system 20 begins charging to an intermediate level in the capacitor 44, a predetermined period of time before the end of pre-CPR chest compressions. In step 102, the system 20 sends a message to the rescuer to stop CPR. Meanwhile, the capacitor is still charged. At 104, a step is delayed for a short period of time, eg, 3 seconds or less. Thereafter, in step 106, the electrodes 22 and 24 connected to the ECG signal front end 32 measure input signals, ie ventricular fibrillation (VF) and patient impedance, low level test signals, or non-treatment. By giving a typical signal.

  In step 108, the ECG signal is tested against other measurements to determine if the ECG signal is corrupted. Signal processing is implemented to emphasize certain features of the data in the input signal. Here, various implementations of processing are used, including known techniques such as filters, Fourier transforms, wavelet transforms or simultaneous time-frequency spectrograms. For example, the low spectral portion of the Fourier transform of the ECG signal can be correlated with a similarly processed impedance signal. This is to increase the detection of artifacts resulting from the defibrillator operator performing CPR on the patient being observed.

  Thus, analysis step 108 performs the function of measuring the similarity between the processed cardiac signal and the processed impaired signal. The comparison results are then analyzed to determine an indication of the amount of artifact present in the heart signal that may be compromised. If artifacts and / or motion are detected at step 108, processing returns to step 106.

  Once step 108 determines that the acquired ECG data is intact, at step 109 the ECG data is analyzed by processor 40 to determine whether a shock is needed. If shock is not required, the AED can provide rescuers with alternative care instructions. However, if the ECG rhythm should be shocked, the AED completes its capacitor charging at step 110. In addition, the absence of an ECG failure signal or motion disturbance signal at step 108 indicates that the rescuer has interrupted CPR, and thus immediately prepares the defibrillator to deliver a shock. Is appropriate. The processor 40 then sends a signal to the HV switch 38 to activate the switch to discharge the desired defibrillation shock to the patient. Alternatively, the processor 40 may inform the operator via the display 42 to press the shock button 36 to manually activate defibrillation shock delivery to the patient. Thus, at step 110, the defibrillation shock is discharged to the patient, and then the patient's heart is observed to determine if a subsequent defibrillation shock is necessary. If necessary, the above steps can be repeated to deliver a subsequent defibrillation shock.

  FIG. 5 is a flow chart illustrating the operational steps for applying an artifact compensated defibrillation shock according to another embodiment of the present invention.

  In operation, the rescuer is instructed to stop the CPR procedure at step 200 and then charging of the capacitor 44 to the full level is initiated. In step 202, a short period is suspended after the rest of CPR compression, and then in step 204, the electrodes 22 and 24 connected to the ECG front end 32 are impaired in the input signals, ie ventricular fibrillation (VF) and patient impedance. Detect along with possible signals and / or input signals due to patient movement during CPR procedures.

  If the ECG signal and disturbance signal are analyzed and artifacts and / or motion disturbances are detected at step 206, the process returns to step 204. If the ECG data is intact, at step 209, the ECG data is analyzed by the processor 40 to determine if a shock is needed. If no shock is required, the AED may provide an alternative care instruction to the rescuer at step 210. The absence of an ECG failure signal or motion disturbance signal at step 108 indicates that the rescuer has interrupted CPR, so it is appropriate to immediately prepare the defibrillator to deliver a shock. is there. If the ECG rhythm should be shocked, the AED completes its capacitor charging at step 208. After the capacitor 44 is fully charged, the processor 40 sends a notification signal to the user prior to delivering the defibrillation shock. In this way, the defibrillation shock is discharged to the patient, and then the patient's heart is observed to determine if a subsequent defibrillation shock is necessary.

  FIG. 6 is a flowchart illustrating operational steps for delivering a defibrillation shock according to yet another embodiment of the present invention.

  In this case, the processor 40 observes the CPR period for a predetermined time. At step 300, as the end of the CPR period approaches, the processor 40 commands the charger 46 to fully charge the capacitor 44 in such a manner that full charge is reached prior to the expiration of the CPR period. Again, prior to the end of the CPR period, various signals indicating disturbances are acquired in step 302 in addition to the ECG data. In step 304, it is examined whether the ECG data is corrupted. If ECG data is corrupted due to CPR, further data is acquired. However, if the data is not compromised, a determination is made at step 306 whether the patient's ECG rhythm should receive a defibrillation shock. In step 308, the processor 40 continues to update the rhythm shock discrimination until the CPR period expires. When the CPR period expires, at step 310, processor 40 causes the audio circuit and speaker 41 to prompt the rescuer not to touch the patient. At step 312, processor 40 checks the most recently determined shock determination. If the defibrillation shock is not appropriate, the device may instruct the rescuer to provide alternative patient care, such as additional CPR. If the shock is appropriate, step 316 examines the disturbance data to ensure that the patient's detectable treatment is over. If no treatment is detected, the processor 40 provides a defibrillator to deliver a shock at step 320 and the AED prompts the rescuer to deliver the shock immediately. The advantage of this embodiment is that if CPR performance does not impair the patient's ECG signal, it is possible to make all of the required decisions for the next shock while CPR is in progress. In this way, the AED can be ready to deliver a shock immediately upon expiration of the CPR period. Thus, the delay between CPR pause and shock can approach 0 seconds.

  FIG. 7 is a flow chart illustrating the operational steps for delivering a defibrillation shock according to another embodiment of the present invention.

  In step 702, electrodes 22 and 24 (FIG. 2) connected to ECG front end 32 measure input signals, such as ventricular fibrillation (VF) and patient impedance, low level test signals, or non-therapeutic signals. Detect by giving In addition, signals that may be compromised and / or input signals due to patient movement are acquired. The motion information is obtained by the motion disturbance detector 10 or the motion sensor. In step 704, a determination is made whether the ECG data is corrupted. If it is determined that the ECG data is corrupted, further data is acquired until the processor 40 can determine whether the shock is appropriate.

  In step 708, the ECG data obtained in step 702 is analyzed by the processor 40 to determine whether a shock is required. A shock may be appropriate if a rhythm capable of delivering the shock is detected, for example, ECG data indicates VF or ventricular tachycardia (VT) as is well known in the art Under certain conditions. The processor 40 can use the analysis described above or known in the art to determine whether a shock is appropriate. Following the determination of whether the shock is appropriate, the processor 40 begins a CPR period and sends a signal to the audio circuit and speaker 41, or to the display 42, or both at step 706 to the rescuer. Give visual and / or audio cues to initiate CPR compression. In an alternative embodiment, steps 706 and 708 are reversed and the CPR period and CPR delivery are initiated prior to determining whether a shock is appropriate. In any order, CPR enforcement and determination of whether shock is appropriate may overlap. In step 710, the voltage charger 46 begins charging the energy storage capacitor network 44 at a time such that full charge is reached prior to completion of the CPR period. Upon completion of the CPR period shown in step 712 in FIG. 7, the processor 40 sends a signal to the audio circuit and speaker 41, or to the display 42, or both, to suspend the CPR from the rescuer and leave the patient. Instruct.

  In step 714, a determination is made whether the analysis performed by processor 40 in step 708 is the result of performing a defibrillation shock. If the shock is not appropriate, the AED may provide the rescuer with an alternative care recommendation at step 715. In contrast, if it is determined that the shock is appropriate, at step 716, processor 40 examines the disturbance data to ensure that the patient's detectable treatment is over. If the disturbance data indicates that the treatment has been suspended, the processor 40 signals in step 718 to the audio circuit and speaker 41, or to the display 42, or both, to touch the patient to the rescuer. Prompt to quit. If no disturbance is detected by the processor 40, the processor 40 provides the defibrillator 20 at step 720 to deliver a defibrillation shock to the patient.

  By following the process as described in connection with FIG. 7, a rhythm that can be shocked is detected from the ECG signal acquired prior to the start of the CPR period and almost immediately after the completion of the CPR period. Is permitted. In this way, the time between CPR compression pause and defibrillation shock delivery can be shortened. The process described above can be used with a variety of different resuscitation procedures.

  While the preferred embodiment of the invention has been illustrated and described, those skilled in the art can make various changes and modifications without departing from the true scope of the invention and substitute equivalents for the elements. You will recognize that. In addition, many modifications may be made to adapt to a particular situation and the teachings of the invention without departing from the central scope. For example, obtaining an ECG signal for analysis can be performed without determining whether the ECG data is corrupted, as in step 704, and still remain within the scope of the present invention. Accordingly, the invention is not limited to the specific embodiments disclosed as the best mode contemplated for carrying out the invention, but the invention is all within the scope of the appended claims. It is intended to include the embodiments.

1 is a diagram of a defibrillator being applied to a patient in cardiac arrest, according to an embodiment of the present invention. FIG. FIG. 2 depicts representative hardware of the defibrillator shown in FIG. 1 in accordance with an embodiment of the present invention. FIG. 2 is a diagram of hardware configured to deliver a defibrillation shock in accordance with an embodiment of the present invention. 6 is a flowchart illustrating operational steps of a defibrillation system according to an embodiment of the present invention. 6 is a flow chart showing operational steps for delivering a defibrillation shock according to another embodiment of the present invention. 6 is a flow chart showing operational steps for delivering a defibrillation shock according to another embodiment of the present invention. 6 is a first half of a flowchart showing operation steps for delivering a defibrillation shock according to another embodiment of the present invention. FIG. 4 is a second half of a flowchart illustrating operation steps for delivering a defibrillation shock according to another embodiment of the present invention.

Claims (20)

A method for delivering a defibrillation shock to a patient from a defibrillator comprising:
Obtain ECG data that represents an electrocardiogram (ECG) signal about the patient,
Analyzing the ECG data to determine if a defibrillation shock is appropriate,
A cardiopulmonary resuscitation (CPR) period is initiated after the acquisition of the ECG data, and CPR compression is performed on the patient during at least a portion of the CPR period;
In response to the completion of the CPR period, if it is determined from the ECG data that defibrillation shock is appropriate, an AED is provided to deliver a defibrillation shock to the patient.
A method involving that.   The method of claim 1, wherein analyzing the ECG data to determine whether a defibrillation shock delivery is appropriate is completed before the CPR period ends.   The analyzing the ECG data to determine whether defibrillation shock delivery is appropriate includes detecting at least one of ventricular fibrillation and ventricular tachycardia from the ECG data. The method according to 1. Obtaining ECG data that represents the ECG signal:
Get ECG signal,
Determine if the ECG signal is impaired by patient movement;
Acquire another ECG signal until an intact signal is obtained,
The method of claim 1, comprising:   The method of claim 1, further comprising delivering a defibrillation shock to the patient after providing the AED.   The method of claim 1, further comprising detecting an indicator of CPR pause prior to providing the AED.   The method of claim 1, further comprising providing an alternative care recommendation if it is determined that defibrillation shock delivery is inappropriate in response to completion of the CPR period. A method for determining the timing of defibrillation shock delivery from an automatic external defibrillator (AED):
Obtain an ECG signal prior to the start of a CPR period,
Prior to completion of the CPR period, determine whether the delivery of defibrillation shock is appropriate,
If it is determined that the delivery of defibrillation shock is appropriate, the AED is provided for delivery of the defibrillation shock upon completion of the CPR period;
Rather, if it is determined that the delivery of the defibrillation shock is inappropriate based on the ECG signal acquired prior to the CPR period, delay the provision of the AED, and Acquire and analyze ECG signals upon completion.
A method involving that.   9. The method of claim 8, wherein analyzing the ECG signal prior to the start of the CPR period comprises analyzing the ECG signal after completion of the previous CPR period.   9. The method of claim 8, wherein analyzing the ECG signal prior to the start of a CPR period comprises analyzing the ECG signal immediately prior to the start of a CPR period.   9. The method of claim 8, wherein determining whether a defibrillation shock is appropriate includes detecting at least one of ventricular fibrillation and ventricular tachycardia from the ECG signal analysis.   9. The method of claim 8, further comprising fully charging a charging capacitor prior to completion of the CPR period.   Further comprising detecting an indicator of CPR cessation prior to providing the AED, wherein providing the AED for delivery of a defibrillation shock is performed immediately after CPR cessation is detected. Item 9. The method according to Item 8.   9. The method of claim 8, further comprising triggering the AED to deliver a defibrillation shock to the patient after providing the AED. A defibrillator for delivering a defibrillation shock:
An energy application unit configured to deliver a defibrillation shock after being provided; and
An electrocardiogram configured to acquire an ECG signal and analyze the ECG signal and to generate a shock appropriate signal in response to determining that the delivery of the defibrillation shock is appropriate based on the ECG signal analysis ( ECG) analysis unit,
A cardiopulmonary resuscitation (CPR) period timer coupled to the ECG analysis unit and configured to start a CPR period after acquisition of the ECG signal and to generate a timeout signal in response to completion of the CPR period;
The energy delivery unit coupled to the ECG analysis unit, the CPR period timer and the energy delivery unit for delivering a defibrillation shock in response to receiving the shock appropriate signal or the time-out signal A preparatory circuit configured to comprise
And a defibrillator.   16. The defibrillator of claim 15, further comprising a charging circuit coupled to the energy application unit for fully charging the energy application unit prior to completion of the CPR period.   16. The defibrillator of claim 15, further comprising a detection circuit for allowing the preparation circuit to include the energy application unit in response to detecting a pause in CPR activity.   16. The defibrillation of claim 15, wherein the ECG analysis unit is configured to generate the shock appropriate signal in response to detecting at least one of ventricular fibrillation and ventricular tachycardia from the ECG signal. Motivation.   ECG signal acquisition configured so that the ECG analysis unit acquires an ECG signal, determines whether the ECG signal is corrupted by motion, and acquires another ECG signal until an intact ECG signal is obtained 16. A defibrillator according to claim 15, comprising a unit. 16. The defibrillator of claim 15, wherein the ECG analysis unit is configured to complete analysis of the ECG signal prior to generating the shock appropriate signal.

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