Pulse monitoring and warning system for infants

• US 8,185,191 B1
• Filed: 02/08/2007
• Issued: 05/22/2012
• Est. Priority Date: 12/29/2003
• Status: Expired due to Fees

• Current Assignee: Michael Evan Shapiro
• Original Assignee: Babn Technologies Corporation (Light & Wonder Incorporated), Michael Evan Shapiro
• Inventors: Shapiro, Michael Evan, Tupin, Joe Paul
• Primary Examiner(s): Mallari, Patricia
• Application Number:
  US11/672,828
• Time in Patent Office: 1,930 Days
• Field of Search: 600/500, 600/503, 600/502, 600/521
• US Class Current: 600/521
• CPC Class Codes: A61B 2503/04 Babies, e.g. for SIDS detection
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/0255 Recording instruments specially adapted therefor
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval

Abstract

A pulse monitoring and warning method and system comprising a sensor disposable over an individual'"'"'s heart and configured to sense a heart rate, the sensor configured to transmit a wireless signal; and a monitor configured to continuously receive a wireless signal from the sensor, the monitor configured to process the signal and produce an alert indication responsive to the heart rate falling below a predetermined level. The system and method employ a QRS detection algorithm, which includes several mechanisms for minimizing the impact of amplitude fluctuation, EMG interference and P/T segment interference. These mechanisms include a variable QRS detection threshold algorithm, a variable QRS search window algorithm, a QRS segment slope/width detector algorithm, and a QRS reacquisition procedure.

Claims

1. A system for monitoring a person'"'"'s heart rate comprising:

a sensor disposable over said person'"'"'s heart and configured to detect QRS segments from an electrocardiogram (ECG) signal corresponding to said person'"'"'s heart rate using an amplitude threshold and a search window, wherein said sensor is configured to automatically adjust said amplitude threshold based on previous QRS segment measurements and transmit a wireless signal to a monitor, said wireless signal comprising information about said detected QRS segments and corresponding heart rate;

said sensor further configured to automatically adjust the temporal location and width of said search window by;

set the width of said search window to a maximum value;

detect a predetermined number of QRS segments using said search window;

store information about said detected predetermined number of QRS segments in memory;

automatically adjust the width of said search window based on said stored information; and

detect subsequent QRS segments using said adjusted search window;

said monitor configured to receive said wireless signal from said sensor, process said signal from said sensor, and produce an alert indication responsive to said person'"'"'s heart rate falling below a predetermined level based on said information in said wireless signal.

2. A system for monitoring a person'"'"'s heart rate comprising:

a sensor disposable over said person'"'"'s heart and configured to detect QRS segments from an electrocardiogram (ECG) signal corresponding to said person'"'"'s heart rate using an amplitude threshold and a search window, wherein said sensor is configured to automatically adjust said amplitude threshold based on previous QRS segment measurements and transmit a wireless signal to a monitor, said wireless signal comprising information about said detected QRS segments and corresponding heart rate;

said sensor configured to;

set said amplitude threshold to a maximum value;

decrease said amplitude threshold from said maximum value until said sensor detects a QRS segment;

detect a predetermined number of QRS segments using said amplitude threshold;

store information about said detected predetermined number of QRS segments in memory;

automatically adjust said amplitude threshold based on said stored information; and

detect subsequent QRS segments using said adjusted amplitude threshold;

said monitor configured to receive said wireless signal from said sensor, process said signal from said sensor, and produce an alert indication responsive to said person'"'"'s heart rate falling below a predetermined level based on said information in said wireless signal.

3. A method for monitoring a person'"'"'s heart rate using a sensor and a monitor, said sensor disposable over said person'"'"'s heart, said method comprising the steps of:

said sensor detecting QRS segments from an electrocardiogram (ECG) signal corresponding to said person'"'"'s heart rate using an amplitude threshold and a search window, wherein said amplitude threshold is automatically adjusted based on previous QRS segment measurements;

said sensor automatically adjusting the temporal location and width of said search window based on said previous QRS segment measurements by;

said sensor setting the width of said search window to a maximum value;

said sensor detecting a predetermined number of QRS segments using said search window;

said sensor storing information about said detected predetermined number of QRS segments in memory; and

said sensor automatically adjusting the width of said search window based on said stored information; and

said sensor detecting subsequent QRS segments using said adjusted search window;

said sensor transmitting a wireless signal to said monitor, said wireless signal comprising information about said detected subsequent QRS segments and corresponding heart rate;

said monitor receiving said wireless signal from said sensor;

said monitor processing said signal from said sensor; and

said monitor producing an alert indication responsive to said person'"'"'s heart rate falling below a predetermined level based on said information in said wireless signal.

4. A method for monitoring a person'"'"'s heart rate using a sensor and a monitor, said sensor disposable over said person'"'"'s heart, said method comprising the steps of:

said sensor detecting QRS segments from an electrocardiogram (ECG) signal corresponding to said person'"'"'s heart rate using an amplitude threshold and a search window, wherein said amplitude threshold is automatically adjusted based on previous QRS segment measurements by;

said sensor setting said amplitude threshold to a maximum value;

said sensor decreasing said amplitude threshold from said maximum value until said sensor detects a QRS segment;

said sensor detecting a predetermined number of QRS segments using said amplitude threshold;

said sensor storing information about said detected predetermined number of QRS segments in memory;

said sensor automatically adjusting said amplitude threshold based on said stored information; and

said sensor detecting subsequent QRS segments using said adjusted amplitude threshold;

said sensor transmitting a wireless signal to said monitor, said wireless signal comprising information about said detected subsequent QRS segments and corresponding heart rate;

said monitor receiving said wireless signal from said sensor;

said monitor processing said signal from said sensor; and

said monitor producing an alert indication responsive to said person'"'"'s heart rate falling below a predetermined level based on said information in said wireless signal.

5. A method for monitoring a person'"'"'s heart rate using a sensor and a monitor, said sensor disposable over said person'"'"'s heart, said method comprising the steps of:

said sensor detecting QRS segments from an electrocardiogram (ECG) signal corresponding to said person'"'"'s heart rate using an amplitude threshold and a search window, by;

detecting a predetermined number of QRS segments using said amplitude threshold;

storing information about said detected predetermined number of QRS segments in memory;

calculating a standard deviation of the amplitude for said detected predetermined number of QRS segments;

automatically adjusting said amplitude threshold based on said standard deviation; and

detecting subsequent QRS segments using said adjusted amplitude threshold;

said sensor transmitting a wireless signal to said monitor, said wireless signal comprising information about said detected subsequent QRS segments and corresponding heart rate;

said monitor receiving said wireless signal from said sensor;

said monitor processing said signal from said sensor; and

said monitor producing an alert indication responsive to said person'"'"'s heart rate falling below a predetermined level based on said information in said wireless signal.

6. The method of claim 5, wherein said step of automatically adjusting said amplitude threshold comprises automatically setting said amplitude threshold to a value that is approximately twice the value of said standard deviation.

7. The method of claim 5, wherein said step of detecting said subsequent QRS segments further comprises said sensor using a template of QRS segment width and QRS segment slope to discriminate between each of said subsequent QRS segments and noise.

8. The method of claim 5, wherein said automatically adjusting said amplitude threshold is performed after losing said ECG signal.

9. The method of claim 8, further comprising gradually decreasing said amplitude threshold and gradually increasing the width of said search window until said ECG signal is reacquired.

10. The method of claim 5, wherein said monitor is equipped with a speaker for providing said alert indication.

11. The method of claim 5, wherein only one said sensor is used to transmit said signal to said monitor.

12. The method of claim 11, wherein said only one said sensor comprises only two electrodes.

13. A system for monitoring a person'"'"'s heart rate comprising:

a sensor disposable over said person'"'"'s heart and configured to detect QRS segments from an electrocardiogram (ECG) signal corresponding to said person'"'"'s heart rate using an amplitude threshold and a search window, wherein said sensor is configured to automatically adjust said amplitude threshold based on previous QRS segment measurements and transmit a wireless signal to a monitor, said wireless signal comprising information about said detected QRS segments and corresponding heart rate;

said sensor further configured to;

detect a predetermined number of QRS segments using said amplitude threshold, store information about said detected predetermined number of QRS segments in memory, calculate a standard deviation of the amplitude for said detected predetermined number of QRS segments, automatically adjust said amplitude threshold based on said standard deviation, and detect subsequent QRS segments using said adjusted amplitude threshold;

said monitor configured to receive said wireless signal from said sensor, process said signal from said sensor, and produce an alert indication responsive to said person'"'"'s heart rate falling below a predetermined level based on said information in said wireless signal.

14. The system of claim 13, wherein said monitor is equipped with a speaker for providing said alert indication.

15. The system of claim 13, wherein said sensor is further configured to automatically set said amplitude threshold to a value that is approximately twice the value of said standard deviation.

16. The system of claim 13, wherein said sensor is further configured to automatically adjust said amplitude threshold after losing said ECG signal.

17. The system of claim 16, wherein said sensor is further configured to gradually decrease said amplitude threshold and gradually increase the width of said search window until said ECG signal is reacquired.

18. The system of claim 13, wherein said sensor comprises only two electrodes.

19. The system of claim 13, wherein said sensor is further configured to use a template of QRS segment width and QRS segment slope to discriminate between each of the subsequent QRS segments and noise.