Defibrillator with user-interactive screen display

• US 5,243,975 A
• Filed: 07/31/1991
• Issued: 09/14/1993
• Est. Priority Date: 07/31/1991
• Status: Expired due to Term

• Current Assignee: Creditanstalt-Bankverein (Unicredit SPA)
• Original Assignee: Physio-Control Incorporated (Stryker Corporation)
• Inventors: O'Connor, Bruce E., Alferness, Clifton A.
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): SCHAETZLE, KENNEDY
• Application Number:
  US07/738,583
• Time in Patent Office: 776 Days
• Field of Search: 128/419 D, 128/734
• US Class Current: 607/7
• CPC Class Codes: A61N 1/3904 External heart defibrillators [EHD]
• CPC Class Codes: A61N 1/3937 Monitoring output parameters
• CPC Class Codes: A61N 1/3993 User interfaces for automatic external defibrillators

Abstract

A defibrillator designed to determine and display (1) the current which is anticipated to be provided to a patient by a defibrillation pulse generated by the defibrillator when the former is to be provided in the form of an energy dose and (2) the energy which is anticipated to be provided to a patient by a defibrillation pulse generated by the defibrillator when the former is to be provided in the form of a current dose. The defibrillator is also designed to determine and display how changes in the transthoracic impedance of the patient will change (1) the magnitude of the selected energy level of the defibrillation pulse when the defibrillator is in the energy dose mode and (2) the magnitude of the selected current level of the defibrillation pulse when the defibrillator is in the current dose mode.

Claims

1. A defibrillator comprising:

generator means for generating a defibrillation pulse;

electrode means for delivering the defibrillation pulse to a patient;

control means coupled to said generator means for permitting a user of the defibrillator to select (1) if the defibrillation pulse generated by said generator means is to be delivered to the patient as an energy dose or as a current dose, and (2) the magnitude of the energy dose or the current dose; and

determination means coupled to said control means (1) for determining prior to delivery of a defibrillation pulse to be delivered as a selected current dose, an energy equivalent which is the energy anticipated to be delivered by the defibrillation pulse, and (2) for determining prior to delivery of a defibrillation pulse to be delivered as a selected energy dose, a current equivalent which is the current anticipated to be delivered by the defibrillation pulse.

2. A defibrillator according to claim 1, further comprising display means coupled to said control means and said determination means for visually displaying said energy equivalent and said current equivalent determined by said determination means.

3. A defibrillator according to claim 2, further wherein said display means is designed to display:

(a) whether the defibrillation pulse is to be delivered in the form of a current dose or an energy dose; and

(b) the selected current level of the defibrillation pulse when the defibrillation pulse is to be delivered as a current dose and the selected energy level of the defibrillation pulse when the defibrillation pulse is to be delivered as an energy dose.

4. A defibrillator according to claim 1, further comprising impedance measuring means for continuously measuring the transthoracic impedance between said patient and said generator means.

5. A defibrillator according to claim 4, wherein said determination means is coupled with said impedance measuring means, and said determination means is designed to continuously determine said current equivalent and said energy equivalent as a function of the impedance measured by said impedance measuring means.

6. A defibrillator according to claim 1, wherein said determination means is additionally designed to determine (1) prior to delivery of a defibrillation pulse to be delivered as a selected current dose, the current which is anticipated to be delivered by the defibrillation pulse, and (2) prior to delivery of a defibrillation pulse to be delivered as a selected energy dose, the energy which is anticipated to be delivered by the defibrillation pulse.

7. A defibrillator according to claim 6, further wherein:

said control means includes selection means for permitting a user of the defibrillator to instruct said determination means to determine said current which is anticipated to be delivered when said defibrillation pulse is to be delivered as a selected current dose and said energy which is anticipated to be delivered when said defibrillation pulse is to be delivered as a selected energy dose; and

said determination means is designed to determine said current which is anticipated to be delivered when said defibrillation pulse is to be delivered as a selected current dose and said energy which is anticipated to be delivered when said defibrillation pulse is to be delivered as a selected energy dose, but only when so instructed by said control means.

8. A defibrillator according to claim 7, further comprising display means coupled to said control means and said determination means for visually displaying:

(a) if the defibrillation pulse is to be delivered in the form of a current dose or an energy dose;

(b) the selected current level of the defibrillation pulse when the defibrillation pulse is to be delivered as a current dose and the selected energy level of the defibrillation pulse when the defibrillation pulse is to be delivered as an energy dose;

(c) said energy equivalent and said current equivalent determined by said determination means; and

(d) if said determination means has been instructed by said selection means to determine the energy which is anticipated to be delivered when the defibrillation pulse is to be delivered as an energy dose and the current which is anticipated to be delivered when the defibrillation pulse is to be delivered as a current dose.

9. A defibrillator according to claim 1, wherein said determination means comprises:

a first look-up table comprising a plurality of energy level values, each being identified by a unique address comprising an associated current level value; and

a second look-up table comprising a plurality of current level values, each being identified by a unique address comprising an associated energy level value.

10. A defibrillator comprising:

generator means for generating a defibrillation pulse;

electrode means for delivering the defibrillation pulse from the generator means to a patient;

control means for permitting a user of the defibrillator (1) to select if the defibrillation pulse is to be delivered as an energy dose or as a current dose, and (2) to choose the magnitude of the selected energy dose or current dose; and

determination means coupled with said electrode means and said control means (a) for determining the quantity of current which is anticipated to be delivered to the patient by the defibrillation pulse when the defibrillation pulse is to be delivered as an energy dose and (2) for determining the quantity of energy which is anticipated to be delivered to the patient by the defibrillation pulse when the defibrillation pulse is to be delivered as a current dose.

11. A defibrillator according to claim 10, further comprising display means coupled with said determination means for displaying:

(a) if the defibrillation pulse is to be delivered as an energy dose or as a current dose; and

(b) the magnitude of said current which is anticipated to be delivered and said energy which is anticipated to be delivered.

12. An energy dose defibrillator comprising:

generator means for generating a defibrillation pulse in the form of an energy dose;

control means coupled to said generator means for permitting a user of the defibrillator to select the energy level of the defibrillation pulse to be generated by said generator means; and

determination means coupled to said control means for determining, prior to generation of a defibrillation pulse, a current equivalent which is the current anticipated to be delivered by the defibrillation pulse.

13. A defibrillator according to claim 12, further comprising display means coupled to said control means and said determination means for visually displaying said current equivalent determined by said determination means.

14. A defibrillator according to claim 13, further wherein said display means is designed to visually display the energy level of the defibrillation pulse selected by the user of the defibrillator.

15. A defibrillator according to claim 12, further comprising impedance measuring means for continuously measuring the transthoracic impedance between a patient and said generator means.

16. A defibrillator according to claim 12, wherein said determination means is additionally designed to determine, prior to application of the defibrillation pulse to be provided as an energy dose, the energy which is anticipated to be discharged by the defibrillation pulse.

17. A defibrillator according to claim 15, wherein said determination means is coupled with said impedance measuring means, and said determination means is designed to continuously determine said current equivalent and said energy equivalent as a function of the impedance measured by said impedance measuring means.

18. A defibrillator comprising:

generator means for generating a defibrillation pulse in the form of an energy dose or a current dose;

electrode means for delivering the defibrillation pulse to a patient;

control means coupled to said electrode means for permitting a user of the defibrillator to select the energy level of the energy dose when the defibrillation pulse is delivered as an energy dose or the current level of the current dose when the defibrillation pulse is delivered as a current dose; and

determination means coupled to said control means for determining, prior to generation of a defibrillation pulse, a current equivalent, which is the current anticipated to be delivered to the patient if the defibrillation pulse is delivered as an energy dose or an energy equivalent, which is the energy anticipated to be discharged by the defibrillation pulse if the defibrillation pulse is delivered as a current dose.

19. A system, for use with a defibrillator of the type capable of delivering a defibrillation pulse to a patient in the form of a current dose or an energy dose, for calculating and displaying the energy which is anticipated to be delivered by a defibrillation pulse delivered as a selected current dose and the current which is anticipated to be delivered by a defibrillation pulse delivered as a selected energy dose, the defibrillator further being of the type including control means for permitting a user to select the quantity of energy or current to be delivered by the defibrillation pulse, and generator means for generating said defibrillation pulse and electrode means for delivering said defibrillation pulse to the patient, the system comprising:

first means, couplable with the defibrillator, for determining an energy equivalent, which is the energy anticipated to be delivered by a defibrillation pulse to be delivered at a current level selected with the control means of the defibrillator, and for determining a current equivalent, which is the current anticipated to be delivered by a defibrillation pulse to be delivered at an energy level selected with the control means of the defibrillator; and

second means, coupled with said first means, for visually displaying (1) the quantity of current selected using the control means of the defibrillator and said energy equivalent of the selected current determined by said first means, and (2) the quantity of energy selected using the control means of the defibrillator and said current equivalent of the selected energy determined by said first means.

20. A system according to claim 19, wherein said first means is designed to determine said energy equivalent and said current equivalent as a function of a predetermined impedance between the generator means of the defibrillator and the patient.

21. A system according to claim 19, wherein the defibrillator with which the system is used comprises impedance detecting means for determining the transthoracic impedance between the generator means and the patient;

further wherein said first means is couplable with the impedance detecting means of the defibrillator and is designed to determine said energy equivalent and said current equivalent as a function of the transthoracic impedance determined by the impedance detecting means.

22. A system according to claim 21, wherein the impedance detecting means of the defibrillator is designed to determine the impedance between the patient and the generator means on a substantially continuous basis;

further wherein said first means is designed to determine said energy equivalent and said current equivalent on a substantially continuous basis.

23. A system, for use with a defibrillator of the type capable of providing a defibrillation pulse to a patient in the form of an energy dose, for calculating and displaying the current which is anticipated to be delivered by a defibrillation pulse provided as a selected energy dose, the defibrillator further being of the type including control means for permitting a user to select the quantity of energy to be provided by the defibrillation pulse, and generator means for generating said defibrillation pulse and electrode means for delivering said defibrillation pulse to the patient, the system comprising:

first means, couplable with the defibrillator, for determining a current equivalent which is the current anticipated to be delivered by a defibrillation pulse to be delivered at an energy level selected with the control means of the defibrillator; and

second means, coupled with said first means, for visually displaying (a) the energy dose level selected using the control means of the defibrillator and (b) said current equivalent of the selected energy dose level determined by said first means.