Pulse sensors

• US 8,064,995 B1
• Filed: 09/02/2010
• Issued: 11/22/2011
• Est. Priority Date: 05/01/2001
• Status: Active Grant

• Current Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Original Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Inventors: White, Sheldon S., Prew, Paul F., Dupelle, Michael R.
• Primary Examiner(s): MANUEL, GEORGE C
• Application Number:
  US12/874,335
• Time in Patent Office: 446 Days
• Field of Search: 607/5
• US Class Current: 607/5
• CPC Class Codes: A61B 5/6822 Neck
• 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 method of operating an automated external defibrillator, the method being implemented by circuitry and one or more processors of the defibrillator, comprising monitoring a pulse signal from the patient; monitoring an ECG signal from the patient; determining whether it is appropriate to deliver a defibrillation shock to the patient, the determination being based at least in part on the content of the ECG signal and on the content of the pulse signal.

Claims

1. An external defibrillator, comprising:

circuitry for delivering a defibrillation pulse to defibrillation electrodes applied to the chest of a patient;

circuitry for monitoring a pulse signal from the patient, wherein the circuitry comprises circuitry for receiving the pulse signal from a stress-detecting sensor substantially in contact with the surface of the patient'"'"'s body and configured to detect motion of the surface of the body caused by blood moving through an artery of the patient;

circuitry for monitoring an ECG signal from the patient;

one or more processors configured to determine whether it is appropriate to deliver a defibrillation shock to the patient, the determination being based at least in part on the content of the ECG signal and on the content of the pulse signal.

2. The defibrillator of claim 1 wherein the stress-detecting sensor is configured to sense stress applied to the sensor.

3. The defibrillator of claim 2 wherein the stress-detecting sensor comprises a piezoelectric sensor.

4. The external defibrillator of claim 1 wherein the circuitry for monitoring an ECG signal comprises circuitry for receiving the ECG signal from the defibrillation electrodes.

5. The external defibrillator of claim 1 wherein the one or more processors is further configured to assist in the delivery of CPR to the patient.

6. The external defibrillator of claim 5 wherein the one or more processors is further configured to determine whether it is appropriate to deliver a defibrillation shock or CPR or neither.

7. The external defibrillator of claim 1 further comprising a user interface to provide information and recommendations to a user of the defibrillator.

8. The external defibrillator of claim 7 wherein the user interface comprises a display.

9. The external defibrillator of claim 7 wherein the one or more processors is configured to determine from the content of the pulse signal and the content of the ECG signal that the patient does not appear to be in cardiac arrest, and to use the user interface to inform the user of that determination.

10. The external defibrillator of claim 7 wherein the one or more processors is configured to determine from the content of the pulse signal and the content of the ECG signal that the patient should not be shocked, and to use the user interface to inform the user of that determination.

11. The external defibrillator of claim 7 wherein the one or more processors is configured to determine from the content of the pulse signal and the content of the ECG signal that the patient should not receive CPR, and to use the user interface to inform the user of that determination.

12. The external defibrillator of claim 7 wherein the one or more processors is configured to make an initial determination from the content of the pulse signal and the content of the ECG signal that the patient should not be shocked, and to use the user interface to inform the user of that initial determination, and following that initial determination to continue to analyze the content of the pulse signal and the ECG signal to make a second determination, based on the pulse becoming unsynchronized with the R-waves of the ECG, that the patient should be treated by administering a shock.

13. The external defibrillator of claim 1 wherein the one or more processors is further configured to perform a comparison of the content of the pulse signal to the content of the ECG signal to determine whether the pulse and ECG are correlated.

14. The external defibrillator of claim 13 wherein the comparison comprises a determination of whether the R wave of the heart rhythm found in the ECG is synchronized with the pulse.

15. The external defibrillator of claim 1 wherein the pulse sensor detects a pulse in a carotid artery.

16. A method of operating an automated external defibrillator, the method being implemented by circuitry and one or more processors of the defibrillator, comprising:

monitoring a pulse signal from the patient, wherein the monitoring is performed by receiving the pulse signal from a stress-detecting sensor substantially in contact with the surface of the patient'"'"'s body and configured to detect motion of the surface of the body caused by blood moving through an artery of the patient;

monitoring an ECG signal from the patient;

determining whether it is appropriate to deliver a defibrillation shock to the patient, the determination being based at least in part on the content of the ECG signal and on the content of the pulse signal.

17. The method of claim 16 wherein the stress-detecting sensor is configured to sense stress applied to the sensor.

18. The method of claim 17 wherein the stress-detecting sensor comprises a piezoelectric sensor.

19. The method of claim 16 wherein the monitoring of an ECG signal comprises receiving the ECG signal from defibrillation electrodes applied to the chest of the patient.

20. The method of claim 16 further comprising providing assistance in the delivery of CPR to the patient.

21. The method of claim 20 further comprising determining whether it is appropriate to deliver a defibrillation shock or CPR or neither.

22. The method of claim 21 further comprising providing a user interface to provide information and recommendations to a user of the defibrillator.

23. The method of claim 22 wherein the user interface comprises a display.

24. The method of claim 22 further comprising determining from the content of the pulse signal and the content of the ECG signal that the patient does not appear to be in cardiac arrest, and using the user interface to inform the user of that determination.

25. The method of claim 22 further comprising determining from the content of the pulse signal and the content of the ECG signal that the patient should not be shocked, and using the user interface to inform the user of that determination.

26. The method of claim 22 further comprising determining from the content of the pulse signal and the content of the ECG signal that the patient should not receive CPR, and using the user interface to inform the user of that determination.

27. The method of claim 22 further comprising making an initial determination from the content of the pulse signal and the content of the ECG signal that the patient should not be shocked, using the user interface to inform the user of that initial determination, and following the initial determination continuing to analyze the content of the pulse signal and the ECG signal to make a second determination, based on the pulse becoming unsynchronized with the R-waves of the ECG, that the patient should be treated by administering a shock.

28. The method of claim 16 further comprising comparing the content of the pulse signal to the content of the ECG signal to determine whether the pulse and ECG are correlated.

29. The method of claim 28 wherein the comparison comprises a determination of whether the R wave of the heart rhythm found in the ECG is synchronized with the pulse.

30. The method of claim 16 wherein the pulse sensor detects a pulse in a carotid artery.