Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A defibrillator for delivering therapeutic electrical energy to a patient's heart generally includes a power source, electrodes, a patient impedance sensor, and a controller. The electrode are capable of being applied to a patient and are operably coupled to the power source. The impedance sensor is couplable to the patient. The controller controls the power source and is communication with the patient impedance sensor. In response to the patient impedance and based thereon, the controller can configure a variety of circuit options to deliver a low current flow defibrillation waveform , which has a substantially constant tilt, to the patient.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: A method of treating a patient for ventricular tachycardia using a wearable defibrillator includes monitoring the patient for a predetermined condition via one or more electrodes on the defibrillator, sending a message to the patient in response to the predetermined condition, activating the defibrillator so that the defibrillator delivers defibrillation energy to the patient, and storing at least one of the results of the monitoring, sending and activating steps in a memory on the defibrillator. The method also includes downloading information stored in the memory of the defibrillator to a base station having an external interface, and transmitting the information downloaded from the memory of the base station to an external location via the external interface of the base station.

Abstract: Electrode devices optimized for long-term wear in conjunction with an external cardiac defibrillator are described. In preferred embodiments the electrode devices include electrodes that consist of multiple segments, thereby providing enhanced efficacy and impedance characteristics relative to conventionally shaped continuous electrodes. In certain embodiments the conductive surface for contacting a patient's skin of the electrodes is continuous but contains regions separated by open spaces, thereby similarly providing enhanced efficacy and impedance characteristics. The electrode devices are fabricated using materials selected to minimize skin irritation and discomfort.

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: An electrode for transcutaneously delivering defibrillation pulses to a patient's heart. The electrode comprises an insulating substrate, a conducting plate which is positioned on the substrate and which has an electrical terminal for making a connection to an external source of electrical current, and a layer of electrolytic gel covering the entire top surface of the conducting plate. This gel contacts a patient's skin when the electrode is positioned on the skin to prevent the conducting plate from contacting the skin. The gel comprises a concentration of an electrolyte such that the combination series resistance of two of the electrodes, when measured with the electrodes configured in a series circuit with a 50 .OMEGA. resistance, and with the electrolytic gel layer of each electrode in contact with that of the other electrode, is greater than 1 .OMEGA. when a 200 Joule defibrillation pulse is discharged into the series circuit.

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.

Abstract: A low cost, mechanical method and apparatus for controlling the size of an internal orifice in a deformable tubing, particularly tubing of a viscoelastic material such as PVC used to administer intravenous fluids. A portion of the tubing is clamped to place a portion of the internal walls of the tubing into contact with one another at a plane of contact. The non-contacting portions of the tubing define at least one flow orifice. The contacting portions are then further compressed so that the wall thickness of the contacting tubes is reduced from its initial, unclamped thickness. The degree of this compression is such as to cause the adjacent tubing wall portions to curve away from the plane of contact, preferably with four point symmetry. This condition is also characterized by the stresses within the tube wall tending to expand or contract the orifice being generally in equilibrium within a brief period of time, typically less than five minutes, during which period the orifice usually expands slightly.