Method and apparatus for delivering electrotherapy having an equivalent probability of success for different patients

A method of delivering electrotherapy, comprising:

• (a) selecting a nominal electrotherapy for a present patient;
• (b) determining the response of a reference patient to the nominal electrotherapy, the reference patient having a patient-dependent electrical parameter of a reference amount;
• (c) measuring a patient-dependent electrical parameter in the present patient that corresponds to the reference patient-dependent electrical parameter;
• and
• (d) controlling the delivery of electrotherapy to the present patient based on the present patient's measured patient-dependent electrical parameter and the determined response of the reference patient to produce an actual electrotherapy that, when delivered to the present patient, has a probability of success for the present patient that is equivalent to the probability of success of the nominal electrotherapy for the reference patient.

A medical device for delivering electrotherapy, comprising:

• (a) electrodes adapted to be placed on a present patient;
• (b) an impedance measuring unit in communication with the electrodes for measuring an impedance of the present patient;
• (c) an electrotherapy generator in communication with the electrodes for delivering electrotherapy to the present patient;
• and
• (d) a processing unit in communication with the impedance measuring unit and the electrotherapy generator for controlling the electrotherapy that is delivered to the present patient, wherein the processing unit is configured to cause the electrotherapy generator to deliver an actual electrotherapy to the present patient based on the present patient's measured impedance and a predetermined response of a reference patient to a nominal electrotherapy, the processing unit controlling the electrotherapy generator so that the actual electrotherapy delivered to the present patient has a probability of success for the present patient that is equivalent to the probability of success of the nominal electrotherapy for the reference patient.

A method of determining a translation factor for use in an electrotherapy device that produces electrotherapy for different patients having an equivalent probability of success for the different patients, the method comprising:

• (a) preparing a quantitative model of an electrotherapy device/patient system defined by the electrotherapy device attached to a patient, the quantitative model including a patient-dependent electrical parameter for the patient;
• (b) selecting a nominal electrotherapy;
• (c) using the quantitative model, determining the model response of a reference patient in the electrotherapy device/patient system to the nominal electrotherapy, the patient-dependent electrical parameter for the reference patient having a reference amount;
• (d) using the quantitative model, determining the model response of different patients in the electrotherapy device/patient system to the nominal electrotherapy, the patient-dependent electrical parameter for the different patients having amounts different than the reference amount;
• (e) comparing the model response of the reference patient with the model response of the different patients to the nominal electrotherapy;
• and
• (f) determining the translation factor to provide an adjustment for the different patients that compensates for relative differences between the model response of the reference patient and the model response of the different patients to the nominal electrotherapy, the adjustment modifying the nominal electrotherapy to define an actual electrotherapy that, when delivered to a patient, produces a model response in the patient that is equivalent to the model response of the reference patient to the nominal electrotherapy.

A defibrillator comprising:

• (a) electrodes adapted for placement on a patient;
• (b) a measuring unit in communication with the electrodes for measuring a patient-dependent electrical parameter of the patient;
• (c) an electrotherapy generator in communication with the electrodes for delivering multiphasic defibrillation therapy to the patient;
• and
• (d) a processing unit in communication with the measuring unit and the electrotherapy generator for controlling the defibrillation therapy that is delivered to the patient, wherein the processing unit is configured to cause the electrotherapy generator to deliver multiphasic defibrillation therapy having an amplitude and phase duration that are determined based on the measured patient-dependent electrical parameter to produce defibrillation therapy having an equivalent probability of success for the patient as for other patients, the defibrillation therapy delivering an amount of energy to the patient that is increased or decreased in relation to a corresponding increase or decrease of the measured patient-dependent electrical parameter of the patient.