Abstract: A defibrillator capable of delivering a damped biphasic truncated (DBT) defibrillation pulse is provided. An energy storage circuit is coupled across a high voltage switch such as an H-bridge for delivering a defibrillation pulse to the patient through a pair of electrodes. A controller operates to control the entire defibrillation process and detects shockable rhythms from the patient via an ECG front end. The energy storage circuit consists of an energy storage capacitor, a series inductor, a shunt diode, and optionally a resistor in series with the inductor. The controller measures as the patient dependent parameter the time interval between the initial delivery of the defibrillation pulse and the occurrence of the peak current or voltage to determine the first and second phases of the defibrillation pulse to provide for compensation for patient impedance.

Abstract: An energy reduction unit is removably connectable to an external defibrillator to reduce the defibrillation energy delivered by the defibrillator to a patient. Use of the energy reduction unit is particularly suited to defibrillating pediatric patients (infants and children under 8) with an automatic or semi-automatic external defibrillator (AED). In one embodiment, the energy reduction unit includes an attenuator which partially dissipates energy produced by the AED. The attenuator is advantageously designed to present an impedance to the AED which, when connected to the patient, is approximately equal to the patient's impedance. The energy reduction unit may include a presence-detect function which enables the defibrillator to modify analysis of ECG signals to account for differences heart rhythms of pediatric and adult patients. In a second embodiment, the energy reduction unit includes an energy control modifier circuit which affects the charging operations performed internal to the AED.

Abstract: A defibrillator configurable for optimal behavior across a broad spectrum of patients, users, and circumstances is provided. A set of environmental characteristics that represent the patient population, the user population, and the possible circumstances are determined and then applied to a configure algorithm to determine an optimal behavior of the defibrillator as reflected through the set up parameters. The set of environmental characteristics can be entered manually or determined from dispatch data supplied by computerized dispatch systems. The optimal behavior can also be achieved using adaptation algorithms such as fuzzy logic and neural networks that allow the defibrillator to obtain measurements of the environmental characteristics and alter its behavior based on those measurements.

Abstract: This invention relates generally to defibrillators and, in particular, to a defibrillator with a built in CPR (“CPR”) prompt system. The invention also relates generally to a defibrillator with a built-in Advanced Cardiac Life Support (“ACLS”) prompt system. Defibrillators include manual defibrillator, automatic or semiautomatic external defibrillators (“AEDs”) and defibrillator trainers. More specifically, this invention is directed to a defibrillator system capable of generating audible prompts and/or visual prompts through an audible prompt generator and a visual prompt generator, wherein the defibrillator instructs a rescuer on performing CPR or ACLS. The instructions are controlled through a prompt generator and may be audible prompts or visual images, or a combination of the two. The prompts may be emitted at a predetermined rate and may be synchronized. This invention is also directed to a method for administering care comprising, providing instructions to a rescuer.

Abstract: A defibrillator capable of delivering a damped biphasic truncated (DBT) defibrillation pulse is provided. An energy storage circuit is coupled across a high voltage switch such as an H-bridge for delivering a defibrillation pulse to the patient through a pair of electrodes. A controller operates to control the entire defibrillation process and detects shockable rhythms from the patient via an ECG front end. The energy storage circuit consists of an energy storage capacitor, a series inductor, a shunt diode, and optionally a resistor in series with the inductor. The controller measures as the patient dependent parameter the time interval between the initial delivery of the defibrillation pulse and the occurrence of the peak current or voltage to determine the first and second phases of the defibrillation pulse to provide for compensation for patient impedance.

Abstract: An electrotherapy method; and an apparatus for delivering electrotherapy to a patient. In particular, a method and apparatus for delivering a lower energy, therapeutically effective electrical waveform to a patient through a defibrillator. The method employed to lower the energy of the waveform can be applied to both internal defibrillators and external defibrillators. Further the method can be applied to any waveform, including monophasic, biphasic or multiphasic. Various custom shapes for a defibrillation waveform can be achieved by adjusting the rate at which the energy is duty cycled throughout any or all phases of the waveform.

Abstract: An electrotherapy apparatus, such as a defibrillator, includes a connecting mechanism coupled between an energy source and electrodes. The connecting mechanism allows selective coupling of the energy source to the electrodes. The energy source includes a capacitor and a high voltage power supply for charging the capacitor. The electrotherapy apparatus further includes a waveform measuring device for measuring a patient ECG waveform. The electrotherapy apparatus also includes a controller coupled to the connecting mechanism, the energy source, and the waveform measuring device. The controller actuates the connecting mechanism to deliver a bi-phasic waveform to the patient. In addition, the controller analyzes the ECG waveform to detect when the patient is experiencing either course arrhythmia or fine arrhythmia.

Abstract: An electrotherapy apparatus, such as a defibrillator, includes a connecting mechanism coupled between an energy source and electrodes. The connecting mechanism allows selective coupling of the energy source to the electrodes. The energy source includes a capacitor and a high voltage power supply for charging the capacitor. The electrotherapy apparatus further includes a waveform measuring device for measuring a patient ECG waveform. The electrotherapy apparatus also includes a controller coupled to the connecting mechanism, the energy source, and the waveform measuring device. The controller actuates the connecting mechanism to deliver a bi-phasic waveform to the patient. In addition, the controller analyzes the ECG waveform to detect when the patient is experiencing either course arrhythmia or fine arrhythmia.

Abstract: An electrotherapy apparatus, such as a defibrillator, includes a connecting mechanism coupled between an energy source and electrodes. The connecting mechanism allows selective coupling of the energy source to the electrodes. The energy source includes a capacitor and a high voltage power supply for charging the capacitor. The electrotherapy apparatus further includes a waveform measuring device for measuring a patient ECG waveform. The electrotherapy apparatus also includes a controller coupled to the connecting mechanism, the energy source, and the waveform measuring device. The controller actuates the connecting mechanism to deliver a bi-phasic waveform to the patient. In addition, the controller analyzes the ECG waveform to detect when the patient is experiencing either course arrhythmia or fine arrhythmia.

Abstract: A defibrillator having an energy storage capacitor network with multiple configurations selected according to patient impedance and desired energy level for delivery of an impedance-compensated defibrillation pulse is provided. The set of configurations may include series, parallel, and series/parallel combinations of energy storage capacitors within the energy storage capacitor network. The impedance-compensated defibrillation pulse may be delivered over an expanded range of energy levels while limiting the peak current to levels that are safe for the patient using configurations tailored for lower impedance patients and limiting the range of defibrillation pulse durations and providing adequate current levels for higher impedance patients. Configurations of the energy storage capacitor network may be readily added to extend the range of energy levels well above 200 joules.

Abstract: An electrotherapy apparatus performs a low level impedance measurement upon the patient to determine the initial charge level on the capacitor used to deliver an electrotherapy waveform to the patient. In addition, the waveform applied to the patient is dynamically controlled to compensate for patient impedance variability. Determining the initial charge level in this manner prevents unnecessarily high peak currents from flowing in low impedance patients while maintaining peak current in high impedance patients at therapeutically beneficial levels. The electrotherapy apparatus includes a measuring device used for measuring a parameter related to the impedance of the patient. The parameter is used for determining low level patient impedance. The measuring device provides a voltage output used by a controller for determining the initial charge level of the capacitor. A first embodiment of a first electrotherapy apparatus includes four electronic switches to deliver a bi-phasic waveform to the patient.

Abstract: This invention relates generally to a device for monitoring an infant for the onset of sudden infant death syndrome (SIDS), detecting the onset of SIDS and providing immediate treatment. In the broadest sense, the invention includes an apparatus for detecting and treating SIDS. The apparatus comprises a data gatherer for monitoring an infant parameter, a controller for communicating with the data gatherer, an energy source operable to power the data gatherer for monitoring the infant parameter and further operable to provide energy to an energy delivery system which is operable to deliver an electric shock from an energy source to an electrode interface, and an alarm which is activated by the controller for alerting a remote caregiver to the onset of symptoms associated with SIDS. The invention also relates to a method of operating a SIDS monitor. The method comprises the steps of monitoring an infant parameter, determining whether the monitored parameter is an acceptable value.

Abstract: This invention is directed to a medical electrode system having a flexible substrate with two electrodes in electrical communication disposed at either end along its length. The electrode system also has one or more sensors for detecting the rate and pressure at which CPR is administered. The electrode is adjustable in length and protects the user from the potential of incidental shock when using the electrode in conjunction with a defibrillator.

Abstract: An energy reduction unit is removably connectable to an external defibrillator to reduce the defibrillation energy delivered by the defibrillator to a patient. Use of the energy reduction unit is particularly suited to defibrillating pediatric patients (infants and children under 8) with an automatic or semi-automatic external defibrillator (AED). In one embodiment, the energy reduction unit includes an attenuator which partially dissipates energy produced by the AED. The attenuator is advantageously designed to present an impedance to the AED which, when connected to the patient, is approximately equal to the patient's impedance. The energy reduction unit may include a presence-detect function which enables the defibrillator to modify analysis of ECG signals to account for differences heart rhythms of pediatric and adult patients. In a second embodiment, the energy reduction unit includes an energy control modifier circuit which affects the charging operations performed internal to the AED.

Abstract: This invention provides an external defibrillator and defibrillation method that automatically compensates for patient-to-patient impedance differences in the delivery of electrotherapeutic pulses for defibrillation and cardioversion. In a preferred embodiment, the defibrillator has an energy source that may be discharged through electrodes on the patient to provide a biphasic voltage or current pulse. In one aspect of the invention, the first and second phase duration and initial first phase amplitude are predetermined values. In a second aspect of the invention, the duration of the first phase of the pulse may be extended if the amplitude of the first phase of the pulse fails to fall to a threshold value by the end of the predetermined first phase duration, as might occur with a high impedance patient.

Abstract: This invention provides an external defibrillator and defibrillation method that automatically compensates for patient-to-patient impedance differences in the delivery of electrotherapeutic pulses for defibrillation and cardioversion. In a preferred embodiment, the defibrillator has an energy source that may be discharged through electrodes on the patient to provide a biphasic voltage or current pulse. In one aspect of the invention, the first and second phase duration and initial first phase amplitude are predetermined values. In a second aspect of the invention, the duration of the first phase of the pulse may be extended if the amplitude of the first phase of the pulse fails to fall to a threshold value by the end of the predetermined first phase duration, as might occur with a high impedance patient.

Abstract: An electrotherapy method and apparatus for delivering a multiphasic waveform from an energy source to a patient. The preferred embodiment of the method comprises the steps of charging the energy source to an initial level; discharging the energy source across the electrodes to deliver electrical energy to the patient in a multiphasic waveform; monitoring a patient-dependent electrical parameter during the discharging step; shaping the waveform of the delivered electrical energy based on a value of the monitored electrical parameter, wherein the relative duration of the phases of the multiphasic waveform is dependent on the value of the monitored electrical parameter.

Abstract: This invention provides an external defibrillator and defibrillation method that automatically compensates for patient-to-patient impedance differences in the delivery of electrotherapeutic pulses for defibrillation and cardioversion. In a preferred embodiment, the defibrillator has an energy source that may be discharged through electrodes on the patient to provide a biphasic voltage or current pulse. In one aspect of the invention, the first and second phase duration and initial first phase amplitude are predetermined values. In a second aspect of the invention, the duration of the first phase of the pulse may be extended if the amplitude of the first phase of the pulse fails to fall to a threshold value by the end of the predetermined first phase duration, as might occur with a high impedance patient.

Abstract: The invention provides a method for delivering electrotherapy to a patient through electrodes connected to a plurality of capacitors, including the steps of discharging at least one of the capacitors across the electrodes to deliver electrical energy to the patient, monitoring a patient-dependent electrical parameter (such as voltage, current or charge) during the discharging step, and adjusting energy delivered to the patient based on a value of the electrical parameter. The adjusting step may include selecting a serial or parallel arrangement for the capacitors based on a value of the electrical parameter.

Abstract: This invention provides an external defibrillator and defibrillation method that automatically compensates for patient-to-patient impedance differences in the delivery of electrotherapeutic pulses for defibrillation and cardioversion. In a preferred embodiment, the defibrillator has an energy source that may be discharged through electrodes on the patient to provide a biphasic voltage or current pulse. In one aspect of the invention, the first and second phase duration and initial first phase amplitude are predetermined values. In a second aspect of the invention, the duration of the first phase of the pulse may be extended if the amplitude of the first phase of the pulse fails to fall to a threshold value by the end of the predetermined first phase duration, as might occur with a high impedance patient.