Method and system for responding to non-perfusing and non-shockable heart rhythms

• US 20080103538A1
• Filed: 10/31/2006
• Published: 05/01/2008
• Est. Priority Date: 11/13/2002
• Status: Active Grant

• Current Assignee: Medtronic Emergency Response Systems Inc (Stryker Corporation)
• Original Assignee: Medtronic Emergency Response Systems Inc (Stryker Corporation)
• Inventors: Walker, Robert G., Owen, James M.
• Granted Patent: US 7,970,464 B2
• Time in Patent Office: Days
• US Class Current: 607/3
• CPC Class Codes: A61B 5/363 Detecting tachycardia or bradycardia
• CPC Class Codes: A61N 1/3925 Monitoring; Protecting

Abstract

A system and method are disclosed for prompting emergency medical personnel who are attending to a patient. When the patient presents a heart rhythm that is a non-perfusing and non-shockable rhythm or perfusing but unstable, the attending personnel are prompted to administer therapy, such as reestablishing perfusion by performing CPR. The attending personnel may also be urged to defer taking the pulse of the patient.

Claims

1. A method comprising the steps of:

detecting in a patient a heart rhythm;

determining that the detected rhythm is either one of (a) a non-perfusing and non-shockable rhythm or (b) a perfusing and unstable rhythm; and

prompting an operator to administer therapy in response to the determination.

2. The method of claim 1, wherein the step of prompting the operator to administer therapy includes prompting the operator to administer CPR.

3. The method of claim 1, wherein the step of prompting the operator to administer therapy includes prompting the operator to administer a drug to the patient.

4. The method of claim 1, further comprising the step of prompting the operator to defer taking a pulse of the patient.

5. The method of claim 1, wherein the step of determining that the detected rhythm is a non-perfusing rhythm and a non-shockable rhythm includes determining that the detected rhythm includes asystole.

6. The method of claim 1, wherein determining that the detected rhythm is a non-perfusing rhythm and a non-shockable rhythm comprises determining that the detected rhythm includes a heart rate below a predetermined threshold.

7. The method of claim 6, wherein the threshold is substantially equal to or less than forty beats per minute.

8. The method of claim 1, wherein the step of determining that the detected rhythm is a non-perfusing rhythm and a non-shockable rhythm comprises determining that the detected rhythm is one chosen from the group consisting of pulseless electrical activity, asystole, profound bradycardia, and atrial electrical activity unaccompanied by ventricular electrical activity.

9. The method of claim 1, further comprising the step of delivering electrical therapy such as a defibrillation shock to the patient.

10. The method of claim 1 further comprising the steps of prompting for a period of CPR and choosing the duration of the prompted CPR period based on a determination made in an ECG analysis.

11. The method of claim 1, wherein the step of determining that the detected rhythm is a non-perfusing rhythm and a non-shockable rhythm comprises analyzing the detected rhythm for a morphological characteristic associated with a non-shockable and non-perfusing ECG rhythm.

12. The method of claim 1, wherein the step of determining that the detected rhythm is a non-shockable rhythm comprises determining that the detected ECG rhythm is unstable.

13. The method of claim 12, wherein the step of determining that the detected rhythm is a perfusing and unstable rhythm comprises determining that the detected rhythm includes R—

R variability above a predetermined threshold, a significant number of ectopic beats, or the appearance of QRS complexes in bursts.

14. The method of claim 13 further comprising the step of determining from the heart rhythm analysis the effectiveness of an administered drug therapy.

15. The method of claim 13 further comprising the step of determining the timing of delivery of additional drug therapy based on the heart rhythm analysis.

16. The method of claim 1, further comprising the steps of:

selecting a health care protocol in response to the determination; and

presenting information pursuant to the protocol to assist the operator attending to the patient.

17. A computer-readable medium comprising instructions for causing a programmable processor to:

determine whether a detected patient heart rhythm is either of (a) a non-perfusing and non-shockable rhythm or (b) a perfusing and unstable rhythm, and

control an output device to prompt an operator to administer therapy in response to the determination.

18. The medium of claim 17, wherein the instructions further cause the processor to:

select a health care protocol in response to the determination; and

cause the output device to present information pursuant to the protocol to assist an operator attending to the patient.

19. The medium of claim 18, wherein the instructions cause the processor to cause the output device to instruct the operator to administer CPR to the patient.

20. The medium of claim 18, wherein the instructions cause the processor to cause the output device to instruct the operator to administer a drug to the patient.

21. A system comprising:

a sensor that detects electrical activity in a patient'"'"'s heart;

a user interface including an output device configured to deliver prompts to a user of the device; and

a processor that is capable of;

receiving a signal indicative of the sensed electrical activity;

analyzing the signal to determine if the heart rhythm is one of (a) a non-perfusing and non-shockable rhythm and (b) a perfusing and unstable rhythm; and

controlling the output device to prompt an operator to administer therapy in response to the determination.

22. The system of claim 21, wherein the processor controls the output device to prompt the operator to administer CPR to the patient.

23. The system of claim 21, wherein the sensor comprises a twelve-lead limb ECG electrode array.

24. The system of claim 21, further comprising an external defibrillation therapy delivery element that provides defibrillation therapy to the patient.

25. The system of claim 21, further comprising memory that stores a plurality of health care protocols,

wherein the processor is further configured to select a health care protocol from the plurality of health care protocols in the memory in response to the determination, and is capable of controlling the output device to cause it to present information pursuant to the selected health care protocol to a user.

26. The system of claim 21, wherein the input/output device comprises one of a touch screen, a speaker, a display screen, or an annunciator.

27. The system of claim 21 wherein the processor chooses a duration of a prompted CPR period based on a determination made in an ECG analysis.

28. The system of claim 21, wherein the processor determines that the detected rhythm is a non-perfusing rhythm and a non-shockable rhythm by analyzing the detected rhythm for a morphological characteristic associated with a non-shockable and non-perfusing ECG rhythm.

29. The system of claim 21 wherein the prompt is an instruction to administer a drug to the patient.

30. The system of claim 21, wherein the prompt is an instruction to defer taking a pulse of the patient.

31. The system of claim 21, wherein the processor is capable of determining that a heart is in asystole.

32. The system of claim 21, wherein the processor is capable of determining that the heart rate is below a predetermined threshold.

33. The system of claim 32 wherein the threshold is substantially equal to or less than forty beats per minute.

34. The system of claim 21, wherein the processor is configured to determine whether the rhythm is any one of pulseless electrical activity, asystole, profound bradycardia, and atrial electrical activity unaccompanied by ventricular electrical activity.

35. The system of claim 21, wherein the processor is capable of determining that an ECG rhythm is unstable.

36. The system of claim 21, wherein the processor is capable of determining that the heart rhythm includes any of R—

R variability, an ectopic beat, or QRS complexes in bursts.

37. The system of claim 21 wherein the processor is capable of using the ECG analysis to determining from the ECG analysis the effectiveness of an administered drug therapy.