Motion detection system for an external defibrillator

• US 20080103402A1
• Filed: 10/30/2006
• Published: 05/01/2008
• Est. Priority Date: 10/30/2006
• Status: Abandoned Application

• Current Assignee: Medtronic Emergency Response Systems Inc (Stryker Corporation)
• Original Assignee: Medtronic Emergency Response Systems Inc (Stryker Corporation)
• Inventors: O'hearn, Patricia J., Jayne, Cynthia P., Stickney, Ronald E., Piraino, Daniel W.
• Application Number:
  US11/590,610
• Publication Number:
  US 20080103402A1
• Time in Patent Office: Days
• US Class Current: 600/509
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/3904 External heart defibrillators [EHD]
• CPC Class Codes: A61N 1/39044 in combination with cardiopulmonary resuscitation [CPR] therapy

Abstract

A medical device capable of analyzing a patient'"'"'s ECG, such as an external defibrillator, may be operated according to a method including the steps of: (a) determining if the patient is undergoing motion; (b) if it is determined that the patient is undergoing motion, providing an indication of patient motion; (c) after providing the indication, determining if the patient is undergoing motion, and if the patient is undergoing motion, starting ECG analysis after an elapsed time T₀. The elapsed time T₀ may be measured from a point in time prior to the commencement of step (a). The method may further include the steps of collecting ECG data of the patient, and initiating analysis of the ECG data prior to step (b). The step (b) may further include the step of interrupting the prior initiated ECG analysis. The method may further include the step of starting a timer when the ECG analysis is commenced, to measure elapsed time.

Claims

1. A method of operating a medical device capable of analyzing a patient'"'"'s ECG comprising the steps of:

(a) determining if the patient is undergoing motion;

(b) if it is determined that the patient is undergoing motion, providing an indication of patient motion;

(c) after providing the indication, determining if the patient is undergoing motion, and if the patient is undergoing motion, starting ECG analysis after an elapsed time T₀.

2. The method of claim 1 wherein the elapsed time T₀ is measured from a point in time prior to the commencement of step (a).

3. The method of claim 1 further comprising the steps of collecting ECG data of the patient, and initiating analysis of the ECG data prior to step (b).

4. The method of claim 3 wherein the step (b) further includes the step of interrupting the prior initiated ECG analysis.

5. The method of claim 1 wherein T₀ is substantially equal to or less than 30 seconds.

6. The method of claim 5 wherein T₀ is substantially equal to or less than 10 seconds.

7. The method of claim 3 wherein determining if the patient is undergoing motion includes sensing patient impedance and analyzing the sensed patient impedance.

8. The method of claim 4 wherein the step of starting the ECG analysis after an elapsed time T₀ includes the step of continuing the ECG analysis that had been interrupted in step (b).

9. The method of claim 4 wherein the step of starting the ECG analysis after an elapsed time T₀ includes the step of commencing a new ECG analysis.

10. The method of claim 1 wherein the indication includes a prompt informing the user that motion is present.

11. The method of claim 10 wherein the prompt includes an instruction to the user to stop motion.

12. The method of claim 10 wherein the prompt includes an instruction to the user to not touch the patient.

13. The method of claim 3 further comprising the step of starting a timer when the ECG analysis is commenced to measure elapsed time.

14. A defibrillator comprising:

electrodes attachable to a patient and configured to sense ECG signals and impedance; and

a processor capable of analyzing the sensed impedance to detect if motion is present; and

, if motion is present, waiting for an elapsed time T₀ before analyzing the ECG signals.

15. The defibrillator of claim 14 further comprising a user interface controlled by the processor, and wherein the processor causes the user interface to inform the user if the processor determines that motion is present.

16. The defibrillator of claim 15 wherein the user interface provides a prompt to the user to stop motion if the processor determines that motion is present.

17. The defibrillator of claim 16 wherein the prompt includes a voice prompt instructing the user to not touch the patient.

18. A method of operating a defibrillator having electrodes attached to a patient comprising the steps of:

starting an ECG analysis of the patient;

starting a measurement of elapsed time when the ECG analysis is started;

analyzing a patient parameter to determine if the patient is undergoing motion which would influence ECG analysis;

if the analyzing step determines that the patient is undergoing motion which would influence ECG analysis, and the time measurement shows that an elapsed time of T₀ has not been reaches, interrupting the ECG analysis.

19. The method of claim 18 further comprising the step of:

after a time T₀ has been reached, analyzing the ECG.

20. The method of claim 19 wherein the step of analyzing the ECG after a time T₀ has been reached includes the step of continuing the ECG analysis which had been interrupted.

21. The method of claim 19 wherein the step of analyzing the ECG after a time T₀ has been reached includes the step of commencing a new ECG analysis.

22. The method of claim 18 further comprising the step of

if the analyzing step determines that the patient is undergoing motion which would influence ECG analysis and the time measurement shows that an elapsed time of T₀ has not been reached, analyzing a second data set of a patient parameter to determine if the patient is undergoing motion which would influence ECG analysis;

and if motion which would influence ECG analysis is present, waiting for an elapsed time T₀ before analyzing the ECG signals.

23. The method of claim 18 wherein the patient parameter is impedance.

24. The method of claim 18 wherein T₀ is substantially equal to 30 seconds.

25. The method of claim 18 wherein T₀ is substantially equal to 10 seconds.

26. The method of claim 18 wherein the time T₀ is a time that is may be chosen prior to application of the electrodes to the patient.