Abstract: A defibrillation system for synchronized cardioversion of a patient includes a first housing that includes a measurement circuit configured to receive electrocardiogram (ECG) signals and measure ECG parameters based on the ECG signals, and a first processor configured to analyze the ECG parameters, and initiate communication of a synchronization signal for a second processor for delivery of one or more defibrillation pulses and further includes a second housing that is separate from and external to the first housing and that includes a shock delivery circuit, and the second processor which is configured to receive the communication of the synchronization signal from the first processor, and control the shock delivery circuit to deliver the one or more defibrillation pulses in response to the synchronization signal.

Abstract: A defibrillation system for synchronized cardioversion of a patient includes a first housing that includes a measurement circuit configured to receive electrocardiogram (ECG) signals and measure ECG parameters based on the ECG signals, and a first processor configured to analyze the ECG parameters, and initiate communication of a synchronization signal for a second processor for delivery of one or more defibrillation pulses and further includes a second housing that is separate from and external to the first housing and that includes a shock delivery circuit, and the second processor which is configured to receive the communication of the synchronization signal from the first processor, and control the shock delivery circuit to deliver the one or more defibrillation pulses in response to the synchronization signal.

Abstract: A method of performing transthoracic defibrillation is described. The method includes generating at least two different defibrillation waveforms using at least two different defibrillation circuits contained in separate housings, delivering each of the at least two different defibrillation waveforms across a respective electrical path of a plurality of electrical paths established across the thoracic cavity and through the heart of a patient by at least three electrodes attached to the thorax of the patient, and synchronizing delivery of the at least two different defibrillation waveforms with communications between the separate housings.

Abstract: External electromagnetic stimulation of the interior of the body by applying three or more electrodes to the exterior of the patient to establish at least two electrical paths across the interior of the patient, determining impedance information representative of an impedance distribution across the interior of the body, delivering an electromagnetic waveform across each of the at least two electrical paths, wherein at least one parameter of the waveform is selected using the impedance information to produce a selected current density distribution at one or more locations within the interior of the body.

Abstract: External electromagnetic stimulation of the interior of the body by applying three or more electrodes to the exterior of the patient to establish at least two electrical paths across the interior of the patient, determining impedance information representative of an impedance distribution across the interior of the body, delivering an electromagnetic waveform across each of the at least two electrical paths, wherein at least one parameter of the waveform is selected using the impedance information to produce a selected current density distribution at one or more locations within the interior of the body.

Abstract: An electrotherapy circuit administers to a patient a current waveform. The electrotherapy circuit includes a charge storage device, at least two discharge electrodes connected by electrical circuitry to opposite poles of the charge storage device, a variable impedance connected between the charge storage device and one of the electrodes, a sensor that senses a patient-dependent electrical parameter (such as a patient impedance sensor), and a control circuit. The control circuit is connected to the sensor and the variable impedance and controls the variable impedance during discharge of the charge storage device based on patient-dependent electrical parameter (such as the patient impedance) sensed by the sensor.

Abstract: The invention provides a method and circuit for forming an electrotherapy current waveform. A charge storage device located externally of a patient's body is charged, and is discharged through the patient's body through at least two discharge electrodes connected by electrical circuitry to opposite poles of the charge storage device. A continuous discharge of the charge storage device through the electrodes is controlled so as to produce at least one phase of a current waveform that includes a ripple. The ripple has a height less than one-third of the height of the peak current of the phase, and the difference between the peak current of the phase and the lowest current of the phase is less than one third of the peak current of the phase. The current waveform has a sensing pulse portion that is integral with the therapeutic discharge portion of the current waveform.

Abstract: An electrotherapy circuit administers to a patient a current waveform. The electrotherapy circuit includes a charge storage device, at least two discharge electrodes connected by electrical circuitry to opposite poles of the charge storage device, a sensor that senses a patient-dependent electrical parameter (such as a patient impedance sensor), and a control circuit. The control circuit is connected to the sensor and the charge storage device and controls discharge of the charge storage device through the electrodes, based on the patient-dependent electrical parameter (such as the patient impedance) as sensed by the sensor. The discharge is controlled in a manner so as to reduce the dependence of peak discharge current on the electrical parameter (such as patient impedance) for a given amount of charge stored by the charge storage device.

Abstract: An electrotherapy circuit administers to a patient a current waveform. The electrotherapy circuit includes a charge storage device, at least two discharge electrodes connected by electrical circuitry to opposite poles of the charge storage device, a sensor that senses a patient-dependent electrical parameter (such as a patient impedance sensor), and a control circuit. The control circuit is connected to the sensor and the charge storage device and controls discharge of the charge storage device through the electrodes.

Abstract: An electrotherapy circuit administers to a patient a current waveform. The electrotherapy circuit includes a charge storage device, at least two discharge electrodes connected by electrical circuitry to opposite poles of the charge storage device, and a control circuit. The control circuit is connected to the charge storage device and controls a continuous discharge of the charge storage device through the electrodes so as to produce at least one phase of a current waveform that includes a sawtooth ripple with a height less than about one-quarter of the average height of the phase.

Abstract: An electrotherapy circuit administers to a patient a current waveform. The electrotherapy circuit includes a storage device, at least two discharge electrodes ted by electrical circuitry to opposite poles of the storage device, a resistive circuit connected between charge storage device and one of the electrodes, and a control circuit. The control circuit is connected to the resistive circuit and controls the resistance of the resistive circuit during discharge of the charge storage so as to shape a current waveform produced between the discharge electrodes.

Abstract: An electrotherapy circuit administers to a patient a current waveform. The electrotherapy circuit includes a charge storage device, at least two discharge electrodes connected by electrical circuitry to opposite poles of the charge storage device, a sensor that senses a patient-dependent electrical parameter (such as a patient impedance sensor), and a control circuit. The control circuit is connected to the sensor and the charge storage device and controls discharge of the charge storage device through the electrodes.

Abstract: A detachable power supply for supplying power from an external power source to a portable defibrillator for charging a battery of the portable defibrillator and operating the portable defibrillator includes a housing shaped to attach to the portable defibrillator and a latch connected to the housing for mechanically attaching the power supply to the defibrillator so that the power supply and the defibrillator form a portable, integral unit.

Abstract: Apparatus for transcutaneously pacing and defibrillating the heart of a patient, having defibrillation pulse discharge circuitry 30 and pacing stimuli generator circuitry 42, both circuits having positive and negative connections 40A, 40B, and 46A, 46B; and including a first multipin connector 49 having four pins at each of which one of the four connections is supplied; a second multipin connector 53 configured to mate with the first multipin connector, and having internal connections to electrically connect the positive connections for the pacing and defibrillation circuitry 40A, 46A and likewise connecting the negative connections of the pacing and defibrillation circuitry 40B, 46B, wherein the positive and negative multifunction connections 58A, 58B are suited for connecting to multifunction electrodes through which both pacing stimuli and defibrillation pulses may be supplied; and a third multipin connector 12 also configured to mate with the first connector, but configured to isolate the pacing connectio

Abstract: Method and apparatus for detecting the open or closed state of a pair of manually-operated switches 116, 118 associated with a pair of defibrillation pulse electrodes, the switches being normally open and being manually closed by an operator, the two switches connected in series with discharge control circuitry 32 for initiating a defibrillation energy pulse. The control circuitry 32 is configured so that when the switches 116, 118 are both closed a defibrillation pulse is initiated. Each of the switches is connected in parallel with a corresponding circuit element 124, 126, each having a characteristic impedance, and being shorted out when the corresponding switch 116, 118 is closed. The invention provides for measuring an indication of the series impedance of the discharge control circuitry 32 to determine the open or closed state of the switches by comparing a measured impedance value indication with an impedance value indication calculated for a given open or closed state of the switches.

Abstract: Method and apparatus for discharging a defibrillation discharge circuit 30 across a short circuit load 166 for monitoring defibrillation pulses 180 generated by the circuit to test that the pulses are acceptable. The discharge circuit 30 comprises an electrical capacitor 34 for storing defibrillation pulse energy and an electrical inductor 38 in series with the capacitor for shaping the discharge pulses. In the invention, parameters representative of the shape of the defibrillation pulse are detected as the pulse is discharged and are compared to predetermined values characteristic of the shape of an acceptable pulse. Based on the outcome of this comparison, an output is provided indicating whether the pulse is acceptable.

Abstract: Method and apparatus for determining the current in a defibrillation pulse discharge circuit 30 which has an inductor 38 with a characteristic inductance for shaping the defibrillation pulses. A sense winding 136 is wound around the inductor with at least one turn between ends of the winding for developing a sense voltage between the ends in response to the current in the inductor as a defibrillation pulse is discharged by the circuit. This sense voltage is measured, and based on the sense voltage and the characteristic inductance of the inductor, the current in the defibrillation discharge pulse is determined.