Abstract: In embodiments, an external defibrillator has an electrical circuit with a special output stage for the high-voltage defibrillation pulse. The output stage includes switches that can turn on for delivering the pulse, and off during all other times. The output stage also includes a diverting resistance to divert electrical current that could leak into the patient while a capacitor is being charged. An optional detector may notify if a component is malfunctioning. An advantage can be that an external defibrillator may be created according to embodiments that uses, in its output stage, semiconductor switches instead of relays. As semiconductor switches weigh less and occupy less volume than relays, an external defibrillator according to embodiments may have less weight and volume. Especially in wearable defibrillator applications, less weight means less effort to carry and less volume means easier concealment under clothing.

Abstract: In embodiments, an external defibrillator has an electrical circuit with a special output stage for the high-voltage defibrillation pulse. The output stage includes switches that can turn on for delivering the pulse, and off during all other times. The output stage also includes a diverting resistance to divert electrical current that could leak into the patient while a capacitor is being charged. An optional detector may notify if a component is malfunctioning. An advantage can be that an external defibrillator may be created according to embodiments that uses, in its output stage, semiconductor switches instead of relays. As semiconductor switches weigh less and occupy less volume than relays, an external defibrillator according to embodiments may have less weight and volume. Especially in wearable defibrillator applications, less weight means less effort to carry and less volume means easier concealment under clothing.

Abstract: In some embodiments, a wearable medical device system includes a processor configured to determine whether a patient requires electrical therapy to be provided via a plurality of therapy electrodes, the electrical therapy comprising discharging at least a portion of a stored electrical charge from an energy storage module, and if so, cause a fluid deploying mechanism to deploy a portion of the stored fluid to an interface between at least two therapy electrodes and the patient's skin prior to providing the electrical therapy, the deployed portion of fluid adapted to decrease the impedance measured by an impedance measurement circuit, and cause the fluid deploying mechanism to deploy an additional portion of fluid in response to the impedance measured by the impedance measurement circuit increasing above a threshold during the electrical therapy.

Abstract: In embodiments, an external defibrillator has an electrical circuit with a special output stage for the high-voltage defibrillation pulse. The output stage includes switches that can turn on for delivering the pulse, and off during all other times. The output stage also includes a diverting resistance to divert electrical current that could leak into the patient while a capacitor is being charged. An optional detector may notify if a component is malfunctioning. An advantage can be that an external defibrillator may be created according to embodiments that uses, in its output stage, semiconductor switches instead of relays. As semiconductor switches weigh less and occupy less volume than relays, an external defibrillator according to embodiments may have less weight and volume. Especially in wearable defibrillator applications, less weight means less effort to carry and less volume means easier concealment under clothing.

Abstract: In embodiments, an external defibrillator has an electrical circuit with a special output stage for the high-voltage defibrillation pulse. The output stage includes switches that can turn on for delivering the pulse, and off during all other times. The output stage also includes a diverting resistance to divert electrical current that could leak into the patient while a capacitor is being charged. An optional detector may notify if a component is malfunctioning. An advantage can be that an external defibrillator may be created according to embodiments that uses, in its output stage, semiconductor switches instead of relays. As semiconductor switches weigh less and occupy less volume than relays, an external defibrillator according to embodiments may have less weight and volume. Especially in wearable defibrillator applications, less weight means less effort to carry and less volume means easier concealment under clothing.

Abstract: A wearable cardioverter defibrillator (“WCD”) system may include an impedance detector configured to render an impedance signal of the patient. The WCD system may determine, from the impedance signal, a characteristic of breathing by the patient that can be used as a vital sign. The WCD system may determine, from at least the breathing characteristic, whether or not a shock criterion is met. If the shock criterion is met, the WCD system may control a discharge circuit to discharge a stored electrical charge through the patient. An advantage can be that the breathing characteristic may be used to determine whether or not a patient is experiencing a condition that requires defibrillation therapy, such as sudden cardiac arrest. Even more advantages can be had in discerning the state of the patient when the breathing characteristic is combined with other data, such as from a motion detector.

Abstract: A wearable cardioverter defibrillator (“WCD”) system may include an impedance detector configured to render an impedance signal of the patient. The WCD system may determine, from the impedance signal, a characteristic of breathing by the patient that can be used as a vital sign. The WCD system may determine, from at least the breathing characteristic, whether or not a shock criterion is met. If the shock criterion is met, the WCD system may control a discharge circuit to discharge a stored electrical charge through the patient. An advantage can be that the breathing characteristic may be used to determine whether or not a patient is experiencing a condition that requires defibrillation therapy, such as sudden cardiac arrest. Even more advantages can be had in discerning the state of the patient when the breathing characteristic is combined with other data, such as from a motion detector.

Abstract: Patient electrodes, patient monitors, defibrillators, wearable defibrillators, software and methods may warn when an electrode stops being fully attached to the patient's skin. A patient electrode includes a pad for attaching to the skin of a patient, a lead coupled to the pad, and a contact detector that can change state, when the pad does not contact fully the skin of the patient. When the detector changes state, an output device may emit an alert, for notifying a rescuer or even the patient.

Abstract: Embodiments are directed to wearable cardioverter defibrillator (WCD) systems that include patient parameter electrodes, such as ECG electrodes, that are at least substantially electrically isolated from other circuits of the WCD system. In embodiments, the WCD system includes a power source, an energy storage module, and a processor each connected to a first circuit ground. A patient parameter sense port, such as an ECG port, is coupled to the patient. A measurement circuit may render a physiological input from the sensed patient parameter received at the patient parameter sense port, and the measurement circuit includes an isolating circuit that electrically isolates the patient parameter sense port from the first circuit ground. The sensing of physiological inputs of the patient can be improved, resulting in fewer erroneous readings and false alarms.

Abstract: In some embodiments, a wearable medical device system includes a processor configured to determine whether a patient requires electrical therapy to be provided via a plurality of therapy electrodes, the electrical therapy comprising discharging at least a portion of a stored electrical charge from an energy storage module, and if so, cause a fluid deploying mechanism to deploy a portion of the stored fluid to an interface between at least two therapy electrodes and the patient's skin prior to providing the electrical therapy, the deployed portion of fluid adapted to decrease the impedance measured by an impedance measurement circuit, and cause the fluid deploying mechanism to deploy an additional portion of fluid in response to the impedance measured by the impedance measurement circuit increasing above a threshold during the electrical therapy.

Abstract: In embodiments, a wearable cardiac defibrillator system includes an energy storage module configured to store a charge. Two electrodes can be configured to be applied to respective locations of a patient. One or more reservoirs can store one or more conductive fluids. Respective fluid deploying mechanisms can be configured to cause the fluids to be released from one or more of the reservoirs, which decreases the impedance at the patient location, and decreases discomfort for the patient. In some embodiments an impedance is sensed between the two electrodes, and the stored charge is delivered when the sensed impedance meets a discharge condition. In some embodiments, different fluids are released for different patient treatments. In some embodiments, fluid release is controlled to be in at least two doses, with an intervening pause.

Abstract: Embodiments are directed to wearable cardioverter defibrillator (WCD) systems that include patient parameter electrodes, such as ECG electrodes, that are at least substantially electrically isolated from other circuits of the WCD system. In embodiments, the WCD system includes a power source, an energy storage module, and a processor each connected to a first circuit ground. A patient parameter sense port, such as an ECG port, is coupled to the patient. A measurement circuit may render a physiological input from the sensed patient parameter received at the patient parameter sense port, and the measurement circuit includes an isolating circuit that electrically isolates the patient parameter sense port from the first circuit ground. The sensing of physiological inputs of the patient can be improved, resulting in fewer erroneous readings and false alarms.

Abstract: Embodiments are directed to wearable cardioverter defibrillator (WCD) systems that include patient parameter electrodes, such as ECG electrodes, that are at least substantially electrically isolated from other circuits of the WCD system. In embodiments, the WCD system includes a power source, an energy storage module, and a processor each connected to a first circuit ground. A patient parameter sense port, such as an ECG port, is coupled to the patient. A measurement circuit may render a physiological input from the sensed patient parameter received at the patient parameter sense port, and the measurement circuit includes an isolating circuit that electrically isolates the patient parameter sense port from the first circuit ground. The sensing of physiological inputs of the patient can be improved, resulting in fewer erroneous readings and false alarms.

Abstract: Patient electrodes, patient monitors, defibrillators, wearable defibrillators, software and methods may warn when an electrode stops being fully attached to the patient's skin. A patient electrode includes a pad for attaching to the skin of a patient, a lead coupled to the pad, and a contact detector that can change state, when the pad does not contact fully the skin of the patient. When the detector changes state, an output device may emit an alert, for notifying a rescuer or even the patient.

Abstract: Patient electrodes, patient monitors, defibrillators, wearable defibrillators, software and methods may warn when an electrode stops being fully attached to the patient's skin. A patient electrode includes a pad for attaching to the skin of a patient, a lead coupled to the pad, and a contact detector that can change state, when the pad does not contact fully the skin of the patient. When the detector changes state, an output device may emit an alert, for notifying a rescuer or even the patient.

Abstract: A wearable medical device includes a garment and a medical device. The medical device has a functionality that can transition between an operative state and an inoperative state. When the functionality is in the inoperative state, a protrusion extends so as to poke the patient, as an indication that steps need to be taken to make the device ready for use.

Abstract: In embodiments, a wearable cardiac defibrillator system includes an energy storage module configured to store a charge. Two electrodes can be configured to be applied to respective locations of a patient. One or more reservoirs can store one or more conductive fluids. Respective fluid deploying mechanisms can be configured to cause the fluids to be released from one or more of the reservoirs, which decreases the impedance at the patient location, and decreases discomfort for the patient. In some embodiments an impedance is sensed between the two electrodes, and the stored charge is delivered when the sensed impedance meets a discharge condition. In some embodiments, different fluids are released for different patient treatments. In some embodiments, fluid release is controlled to be in at least two doses, with an intervening pause.

Abstract: A wearable cardioverter defibrillator (“WCD”) system may include an impedance detector configured to render an impedance signal of the patient. The WCD system may determine, from the impedance signal, a characteristic of breathing by the patient that can be used as a vital sign. The WCD system may determine, from at least the breathing characteristic, whether or not a shock criterion is met. If the shock criterion is met, the WCD system may control a discharge circuit to discharge a stored electrical charge through the patient. An advantage can be that the breathing characteristic may be used to determine whether or not a patient is experiencing a condition that requires defibrillation therapy, such as sudden cardiac arrest. Even more advantages can be had in discerning the state of the patient when the breathing characteristic is combined with other data, such as from a motion detector.

Abstract: In embodiments, a wearable cardiac defibrillator system includes an energy storage module configured to store a charge. Two electrodes can be configured to be applied to respective locations of a patient. One or more reservoirs can store one or more conductive fluids. Respective fluid deploying mechanisms can be configured to cause the fluids to be released from one or more of the reservoirs, which decreases the impedance at the patient location, and decreases discomfort for the patient. In some embodiments an impedance is sensed between the two electrodes, and the stored charge is delivered when the sensed impedance meets a discharge condition. In some embodiments, different fluids are released for different patient treatments. In some embodiments, fluid release is controlled to be in at least two doses, with an intervening pause.

Abstract: A wearable medical device includes a garment and a medical device. The medical device has a functionality that can transition between an operative state and an inoperative state. When the functionality is in the inoperative state, a protrusion extends so as to poke the patient, as an indication that steps need to be taken to make the device ready for use.