Apparatus for controlling delivery of defibrillation energy
DCFirst Claim
1. A circuit for producing a high energy pulse for application to a patient experiencing ventricular fibrillation, comprising:
- a storage circuit operable to store electrical energy;
a steering circuit coupled with the storage circuit, the steering circuit being adapted for coupling with the patient and operable to deliver the electrical energy from the storage circuit to the patient; and
a protection circuit coupled with the storage circuit and with the steering circuit and operable to respond to a detected fault condition to selectively control the delivery of electrical energy from the storage circuit to the steering circuit.
4 Assignments
Litigations
0 Petitions
Accused Products
Abstract
An automatic external defibrillator is described that includes a high voltage delivery circuit for producing an electrical pulse to defibrillate a patient. In a preferred embodiment the electrical pulse is a biphasic or multiphasic electrical pulse. In one embodiment, the delivery circuit includes a high voltage capacitor coupled with a bridge circuit. The capacitor stores electrical energy for delivery to the patient, and the bridge circuit has four switching elements that are selectively switched to steer the current through the patient. A disarm circuit shunts the bridge circuit and operates to route energy away from the bridge circuit in the event a fault condition is detected, such as a short circuit at the patient electrodes. An example disarm circuit is a series-connected SCR and resistor. Also, a limiting circuit element (such as a resistor or an inductor) is provided in series with the capacitor. Together with the disarm circuit, the limiting circuit element reduces the voltage experienced by the bridge circuit switching elements when switched off in response to the detected fault condition. Consequently simpler, more robust, and less expensive high voltage delivery circuits are provided, as compared to conventional defibrillator circuit designs. A snubber circuit is also provided to prevent voltage from reaching the patient when the device is in standby mode.
39 Citations
58 Claims
-
1. A circuit for producing a high energy pulse for application to a patient experiencing ventricular fibrillation, comprising:
-
a storage circuit operable to store electrical energy;
a steering circuit coupled with the storage circuit, the steering circuit being adapted for coupling with the patient and operable to deliver the electrical energy from the storage circuit to the patient; and
a protection circuit coupled with the storage circuit and with the steering circuit and operable to respond to a detected fault condition to selectively control the delivery of electrical energy from the storage circuit to the steering circuit. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A circuit for producing a high energy pulse for application to a patient experiencing ventricular fibrillation, comprising:
-
a storage circuit operable to store electrical energy;
a steering circuit coupled with the storage circuit, the steering circuit adapted for coupling with the patient and operable to deliver the electrical energy from the storage circuit to the patient; and
a disarm circuit coupled with the storage circuit and with the steering circuit, the disarm circuit operable to selectively shunt delivery of the electrical energy away from the steering circuit. - View Dependent Claims (13, 14, 15)
-
-
16. A circuit for producing a high energy pulse for application to a patient experiencing ventricular fibrillation, comprising:
-
a storage circuit operable to store electrical energy;
a steering circuit coupled with the storage circuit, the steering circuit adapted for coupling with the patient and operable to deliver the electrical energy from the storage circuit to the patient; and
a limit circuit coupling the storage circuit with the steering circuit, the limit circuit operable to limit the delivery of the electrical energy from the storage circuit to the steering circuit. - View Dependent Claims (17, 18, 19)
-
-
20. A circuit for producing a high energy pulse for application to a patient experiencing ventricular fibrillation, comprising:
-
a storage circuit operable to store electrical energy;
a steering circuit coupled with the storage circuit, the steering circuit being adapted for coupling with the patient and operable to deliver the electrical energy from the storage circuit to the patient;
a disarm circuit coupled with the storage circuit and with the steering circuit and operable to selectively shunt delivery of the electrical energy away from the steering circuit; and
a limit circuit coupling the storage circuit with the steering circuit and operable to limit delivery of the electrical energy from the storage circuit to the steering circuit, the disarm circuit and limit circuit together operable to substantially limit a maximum voltage applied across the steering circuit. - View Dependent Claims (21, 22, 23, 24)
-
-
25. A circuit for producing a high energy pulse for application to a patient experiencing ventricular fibrillation, comprising:
-
a storage circuit having first and second terminals and operable to store electrical energy therebetween;
a steering circuit coupled with the first terminal of the storage circuit, the steering circuit adapted for coupling with the patient and operable to deliver the electrical energy from the storage circuit to the patient;
a disarm circuit coupled with the first and second terminals of the storage circuit, the disarm circuit operable to selectively shunt delivery of the electrical energy away from the steering circuit; and
a switching circuit coupled with the steering circuit and with the second terminal of the storage circuit, the switching circuit operable to electrically connect and disconnect the steering circuit to and from the second terminal of the storage circuit to initiate and interrupt the delivery of electrical energy through the steering circuit, all respectively. - View Dependent Claims (26, 27, 28, 29, 30)
-
-
31. In an electrical defibrillator for defibrillating a patient experiencing ventricular fibrillation, a method of delivering electrical energy to the patient, comprising the steps of:
-
storing electrical energy;
initiating delivery of the electrical energy to the patient;
measuring an electrical value associated with the delivery; and
if the measured electrical value falls within a predetermined range of acceptable values, then continuing delivery of the electrical energy to the patient;
orif the measured electrical value does not fall within the range of acceptable values, the method then further comprising the steps of, interrupting delivery of the electrical energy to the patient; and
discharging remaining stored electrical energy. - View Dependent Claims (32, 33, 34)
-
-
35. In an electrical defibrillator for defibrillating a patient experiencing ventricular fibrillation, a method of delivering electrical energy to the patient, comprising the steps of:
-
storing electrical energy;
initiating delivery of the electrical energy to the patient;
limiting the delivery of the electrical energy;
measuring an electrical value associated with the delivery; and
if the measured electrical value falls within a predetermined range of acceptable values, then continuing delivery of the electrical energy to the patient;
orif the measured electrical value does not fall within the range of acceptable values, the method then further comprising the steps of, interrupting delivery of the electrical energy to the patient; and
discharging remaining stored electrical energy. - View Dependent Claims (36, 37, 38, 39)
-
-
40. In an electrical defibrillator having a storage circuit coupled with a steering circuit, the storage circuit for storing electrical energy and the steering circuit for directing the electrical energy to a patient, a method of delivering electrical energy to a patient, comprising the steps of:
-
charging the storage circuit to store electrical energy therein;
forming a first electrical path from the storage circuit to the patient through the steering circuit;
initiating delivery of the electrical energy via the first electrical path;
sensing the rate at which the electrical energy is delivered via the first path; and
if the rate falls within a predetermined acceptable range, then continuing to deliver the electrical energy via the first electrical path;
orif the rate does not fall within the acceptable range, the method then further comprising the steps of, forming a second electrical path from the storage circuit; and
opening the first electrical path. - View Dependent Claims (41, 42, 43)
-
-
44. In an electrical defibrillator having a storage circuit coupled with a steering circuit, the storage circuit for storing electrical energy and the steering circuit for directing the electrical energy to a patient, a method of delivering electrical energy to a patient, comprising the steps of:
-
charging the storage circuit to store electrical energy therein;
forming a first electrical path from the storage circuit to the patient through the steering circuit;
initiating delivery of the electrical energy via the first electrical path;
limiting the delivery of the electrical energy;
sensing the rate at which the electrical energy is delivered via the first path; and
if the rate falls within a predetermined acceptable range, then continuing to deliver the electrical energy via the first electrical path;
orif the rate does not fall within the acceptable range, the method then further comprising the steps of, forming a second electrical path from the storage circuit; and
opening the first electrical path. - View Dependent Claims (45, 46, 47, 48, 49)
-
-
50. In an electrical defibrillator having a storage circuit coupled with a steering circuit, the storage circuit for storing electrical energy and the steering circuit for directing the electrical energy to a patient, a method of delivering electrical energy to a patient, comprising the steps of:
-
storing electrical energy in the storage circuit;
initiating electrical current flow through the steering circuit; and
measuring a current magnitude of the electrical current flow through the steering circuit;
if the current magnitude falls within a predetermined acceptable range, then continuing to allow the electrical current flow through the steering circuit;
orif the current magnitude does not fall within the acceptable range, the method then further comprising the steps of, forming an electrical path shunting the steering circuit;
controlling voltage applied across the steering circuit; and
stopping the electrical current flow through the steering circuit. - View Dependent Claims (51, 52, 53)
-
-
54. In an electrical defibrillator having a switching circuit coupling a storage circuit with a steering circuit, the storage circuit for storing electrical energy, the steering circuit for directing the electrical energy to a patient, and the switching circuit for initiating and stopping the transfer of electrical energy from the storage circuit to the steering circuit, a method of delivering electrical energy to a patient, comprising the steps of:
-
storing electrical energy in the storage circuit;
initiating electrical current flow through the steering circuit; and
measuring a current magnitude of the electrical current flow through the steering circuit;
if the current magnitude falls within a predetermined acceptable range, then continuing to allow the electrical current flow through the steering circuit;
orif the current magnitude does not fall within the acceptable range, the method then further comprising the steps of, forming an electrical path shunting the steering circuit;
controlling voltage applied across the switching circuit; and
stopping the electrical current flow through the steering circuit. - View Dependent Claims (55, 56, 57, 58)
producing a clamping voltage level in the electrical path shunting the steering circuit; and
coupling the switching circuit to the clamping voltage level.
-
-
58. A method according to claim 54 wherein if the current magnitude does not fall within the acceptable range, the method further comprising the step of substantially dissipating remaining electrical energy stored in the storage circuit.
Specification