Uterine activity monitor and method of the same

• US 6,421,558 B1
• Filed: 06/29/2000
• Issued: 07/16/2002
• Est. Priority Date: 06/29/2000
• Status: Expired due to Fees

• Current Assignee: GE Medical Systems Information Technologies Incorporated (General Electric Company)
• Original Assignee: GE Medical Systems Information Technologies Incorporated (General Electric Company)
• Inventors: Huey, Raymond J., Reynolds, Charles A., Kosturko, William
• Primary Examiner(s): Shaver, Kevin
• Assistant Examiner(s): SZMAL, BRIAN SCOTT
• Application Number:
  US09/606,707
• Time in Patent Office: 747 Days
• Field of Search: 600/546, 600/588, 600/300, 600/587, 607/20, 607/28, 607/25, 607/26
• US Class Current: 600/546
• CPC Class Codes: A61B 5/391 of genito-urinary organs
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence

Abstract

A method and apparatus for generating a signal representing uterine activity. The method including the acts of obtaining a uterine electromyography (EMG) signal, and processing the uterine EMG signal to produce a signal representative of uterine activity. The apparatus including a sensor for acquiring a uterine electromyography (EMG) signal, and a signal processor for generating a signal representative of uterine activity in response to the uterine EMG signal.

Claims

1. A method of generating a signal representing uterine activity, the method comprising:

obtaining a uterine electromyography (EMG) signal;

processing the uterine EMG signal to produce a signal representative of uterine activity; and

wherein the act of processing the uterine EMG signal comprises the acts of;

sampling the uterine EMG signal to create a bipolar digital waveform;

converting the bipolar digital waveform to a unipolar digital waveform; and

time averaging the unipolar digital waveform to obtain the signal representative of uterine activity.

2. A method as set forth in claim 1, wherein the signal representative of uterine activity indicates uterine contraction duration.

3. A method as set forth in claim 1, wherein the signal representative of uterine activity indicates uterine contraction frequency.

4. A method as set forth in claim 1, wherein the signal representative of uterine activity approximates at least one component of a signal that would be acquired using an intrauterine pressure sensor.

5. A method as set forth in claim 1, wherein the signal representative of uterine activity approximates a signal that would be acquired using a tocodynomometer.

6. A method as set forth in claim 1, wherein the act of processing the uterine EMG signal comprises the acts of:

amplifying the uterine EMG signal; and

filtering the uterine EMG signal.

7. A method as set forth in claim 1, wherein the act of processing the uterine EMG signal further comprises the acts of:

scaling the signal representative of uterine activity; and

storing the signal representative of uterine activity.

8. A method of generating a signal representing uterine activity, the method comprising:

obtaining a uterine electromyography (EMG) signal;

processing the uterine EMG signal to produce a signal representative of uterine activity; and

wherein the act of processing the uterine EMG signal further comprises the acts of;

rectifying the uterine EMG signal to obtain a rectified signal; and

applying the rectified signal to a peak detector to obtain the signal representative of uterine activity.

9. A method as set forth in claim 8, wherein the signal obtained from the peak detector is an analog signal representative of uterine activity, and

wherein the act of processing the uterine EMG signal further comprises the acts of:

sampling the analog signal representative of uterine activity to obtain data for a digital signal representative of uterine activity; and

storing the data of the digital signal representative of uterine activity.

10. A method as set forth in claim 9, wherein the act of processing the uterine EMG signal further comprises the acts of:

scaling the data of the digital signal representative of uterine activity; and

displaying the digital signal representative of uterine activity.

11. A method as set forth in claim 8, wherein the signal representative of uterine activity indicates uterine contraction duration.

12. A method as set forth in claim 8, wherein the signal representative of uterine activity indicates uterine contraction frequency.

13. A method as set forth in claim 8, wherein the signal representative of uterine activity approximates at least one component of a signal that would be acquired using an intrauterine pressure sensor.

14. A method as set forth in claim 8, wherein the signal representative of uterine activity approximates a signal that would be acquired using a tocodynomometer.

15. A method as set forth in claim 8, wherein the act of processing the uterine EMG signal comprises the acts of:

amplifying the uterine EMG signal; and

filtering the uterine EMG signal.

16. A monitor comprising:

a sensor for acquiring a uterine electromyography (EMG) signal;

a signal processor for generating a signal representative of uterine activity in response to the uterine EMG signal;

wherein the signal processor comprises;

a receiver that receives the uterine EMG signal from the sensor and generates an analog signal representative of uterine activity; and

wherein the receiver comprises;

an amplifier and filter for amplifying and filtering the received uterine EMG signal to generate a processed uterine EMG signal;

a full wave rectifier electrically connected to the amplifier and filter, the full wave rectifier rectifies the processed uterine EMG signal from the amplifier and filter to generate a rectified signal; and

a peak detector electrically connected to the full wave rectifier for generating a peak value signal having the peak values of the rectified signal, the generated peak value signal is the analog signal representative of uterine activity.

17. A monitor as set forth in claim 16, wherein the signal representative of uterine activity indicates uterine contraction duration.

18. A monitor as set forth in claim 16, wherein the signal representative of uterine activity indicates uterine contraction frequency.

19. A monitor as set forth in claim 16, wherein the signal representative of uterine activity approximates at least one component of a signal that would be acquired using an intrauterine pressure sensor.

20. A monitor as set forth in claim 16, wherein the signal representative of uterine activity approximates a signal that would be acquired using a tocodynomometer.

21. A monitor as set forth in claim 16, wherein the signal processor further comprises:

a microprocessor electrically connected to the receiver for receiving the analog signal representative of uterine activity and converting the analog signal representative of uterine activity into a digital signal representative of uterine activity; and

a memory unit electrically connected to the microprocessor for storing the digital signal representative of uterine activity.

22. A monitor comprising:

a sensor for acquiring a uterine electromyography (EMG) signal;

a signal processor for generating a signal representative of uterine activity in response to the uterine EMG signal; and

wherein the signal processor further comprises;

an amplifier and filter for amplifying and filtering the received uterine EMG signal to generate a processed uterine EMG signal;

a microprocessor that receives the processed uterine EMG signal and generates the signal representative of uterine activity, the microprocessor generating the signal representative of uterine activity by sampling the processed uterine EMG signal to create a bipolar digital waveform, converting the bipolar digital waveform to a unipolar digital waveform, and time averaging the unipolar digital waveform to obtain the signal representative of uterine activity; and

a memory unit electrically connected to the microprocessor for storing the signal representative of uterine activity.

23. A monitor as set forth in claim 22, wherein the signal representative of uterine activity indicates uterine contraction duration.

24. A monitor as set forth in claim 22, wherein the signal representative of uterine activity indicates uterine contraction frequency.

25. A monitor as set forth in claim 22, wherein the signal representative of uterine activity approximates at least one component of a signal that would be acquired using an intrauterine pressure sensor.

26. A monitor as set forth in claim 22, wherein the signal representative of uterine activity approximates a signal that would be acquired using a tocodynomometer.

27. A system for generating a signal representing uterine activity, the system comprising:

a sensor for obtaining a uterine electromyography (EMG) signal; and

means for processing the uterine EMG signal to produce a signal representative of uterine activity,

wherein the processing means comprises;

means for sampling the processed uterine EMG signal to create a bipolar digital waveform;

means for converting the bipolar digital waveform to a unipolar digital waveform; and

means for time averaging the unipolar digital waveform to obtain the signal representative of uterine activity.

28. A system as set forth in claim 27, wherein the signal representative of uterine activity indicates uterine contraction duration.

29. A system as set forth in claim 27, wherein the signal representative of uterine activity indicates uterine contraction frequency.

30. A system as set forth in claim 27, wherein the signal representative of uterine activity approximates at least one component of a signal that would be acquired using an intrauterine pressure sensor.

31. A system as set forth in claim 27, wherein the signal representative of uterine activity approximates a signal that would be acquired using a tocodynomometer.

32. A system as set forth in claim 27, wherein the means for processing the uterine EMG signal comprises:

means for generating an analog signal representative of uterine activity in response to a received uterine EMG signal.

33. A system as set forth in claim 32, wherein the means for processing the uterine EMG signal comprises:

means for converting the analog signal representative of uterine activity to a digital signal representative of uterine activity; and

means for storing the digital representative signal.

34. A software program for operating a monitor, the monitor including a sensor for acquiring a uterine electromyography (EMG) signal and a microprocessor for executing the software program, the software program operating the monitor by:

sampling the uterine EMG signal to obtain a bipolar digital waveform;

processing the uterine EMG signal to produce a signal representative of uterine activity; and

wherein the act of processing the uterine EMG signal further comprises the acts of;

converting the bipolar digital waveform to a unipolar digital waveform; and

time averaging the unipolar digital waveform to obtain the signal representative of uterine activity.

35. A software program as set forth in claim 34, wherein the signal representative of uterine activity indicates uterine contraction duration.

36. A software program as set forth in claim 34, wherein the signal representative of uterine activity indicates uterine contraction frequency.

37. A software program as set forth in claim 34, wherein the signal representative of uterine activity approximates at least one component of a signal that would be acquired using an intrauterine pressure sensor.

38. A software program as set forth in claim 34, wherein the signal representative of uterine activity approximates a signal that would be acquired using a tocodynomometer.

39. A method of generating a signal representing uterine activity, the method comprising:

obtaining a uterine electromyography (EMG) signal;

amplifying the EMG signal;

filtering the EMG signal;

rectifying the EMG signal to obtain a rectified signal;

applying the rectified signal to a peak detector to obtain an analog signal representative of uterine activity;

sampling the analog signal representative of uterine activity to obtain data for a digital representative signal;

scaling the data of the digital signal representative of uterine activity; and

displaying the digital signal representative of uterine activity.

40. A method as set forth in claim 39, wherein the signal representative of uterine activity approximates at least one component of a signal that would be acquired using an intrauterine pressure sensor.

41. A method as set forth in claim 39, wherein the signal representative of uterine activity approximates a signal that would be acquired using a tocodynomometer.

42. A monitor comprising:

a sensor for acquiring a uterine electromyography (EMG) signal;

a signal processor for generating a signal representative of uterine activity in response to the uterine EMG signal, the signal representative of uterine activity indicates uterine contraction duration and uterine contraction frequency, the signal comprises;

a receiver for receiving the uterine EMG signal and generating an analog signal representing of uterine activity;

a microprocessor electrically connected to the receiver for receiving the analog signal representative of uterine and converting the analog signal representative of uterine activity into a digital signal representative of uterine activity; and

a memory unit electrically connected to the microprocessor for storing the digital signal representative of uterine activity; and

wherein the receiver comprises;

an amplifier and filter for amplifying and filtering the received uterine EMG signal;

a full wave rectifier electrically connected to the amplifier and filter, the full wave rectifier rectifies the resultant signal from the amplifier and filter to generate a rectified signal; and

a peak detector electrically connected to the fill wave rectifier for generating a peak value signal having the peak values of the rectified signal, the generated peak value signal is the analog signal representative of uterine activity.

43. A monitor as set forth in claim 42, wherein the signal representative of uterine activity approximates at least one component of a signal that would be acquired using an intrauterine pressure sensor.

44. A monitor as set forth in claim 42, wherein the signal representative of uterine activity approximates a signal that would be acquired using a tocodynomometer.