FETAL ECG MONITORING

• US 20090259133A1
• Filed: 04/15/2009
• Published: 10/15/2009
• Est. Priority Date: 04/15/2008
• Status: Active Grant

• Current Assignee: E-Trolz, Inc., Tufts Medical Center Incorporated (Healthcare Realty Trust, Inc.), Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Ward, Jay, Clifford, Gari D., Wolfberg, Adam J.
• Granted Patent: US 7,949,389 B2
• Time in Patent Office: Days
• US Class Current: 600/511
• CPC Class Codes: A61B 5/02411 of foetuses
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/344 Foetal cardiography
• CPC Class Codes: A61B 5/412 Detecting or monitoring sepsis
• CPC Class Codes: A61B 5/4362 Assessing foetal parameters

Abstract

A method for fetal monitoring includes acquiring electrical signals from a set of electrodes, for example, a set of surface electrodes applied to a maternal abdominal region. The electrical signals are analyzed, including by performing a morphological analysis of fetal electrocardiogram signals. A clinical indicator is then determined from a result of performing the morphological analysis.

Claims

1. A fetal monitoring system comprising:

a data acquisition system for acquiring signals including signals representing surface measurements of cardiac activity;

a signal analyzer coupled to the data acquisition system, configured to analyze the acquired signals to generate an output having at least an clinical indicator characterizing a clinical condition, the signal analyzer including;

a signal processor for extracting fetal electrocardiogram signals from the acquired electrical signals; and

a clinical condition detector for performing a morphological analysis of the extracted fetal electrocardiogram signals, and based on a result of the morphological analysis, determining the clinical indicator; and

an output system for presenting a representation of the clinical indicator.

2. The fetal monitoring system of claim 1, wherein the output system includes a display unit for generating a visual representation of the output of the signal analyzer.

3. The fetal monitoring system of claim 1, wherein the data acquisition system includes an electrode array having at least a plurality of electrodes attachable to a maternal abdominal region.

4. The fetal monitoring system of claim 3, wherein the electrode array further includes a second plurality of electrodes attachable to a maternal lumbar region.

5. The fetal monitoring system claim 4, wherein the electrode array further includes a third plurality of electrodes attachable to a maternal side region.

6. The fetal monitoring system of claim 5, wherein the pluralities of electrodes are positioned in a pre-determined arrangement on a garment.

7. The fetal monitoring system of claim 1, wherein the signal analyzer further includes a heart rate detector for determining a fetal heart rate from the acquired signals.

8. The fetal monitoring system of claim 7, wherein the output system is further configured for presenting a representation of the fetal heart rate determined by the signal analyzer.

9. The fetal monitoring system of claim 7, wherein the heart rate detector is further configured for determining a degree of irregularity in the fetal heart rate.

10. The fetal monitoring system of claim 1, wherein the output system is further configured for presenting a waveform representation of the fetal electrocardiogram signals.

11. The fetal monitoring system of claim 1, wherein the clinical condition detector is further configured for determining a measure of morphological variation in the extracted fetal electrocardiogram signals.

12. The fetal monitoring system of claim 11, wherein the measure of morphological variation includes an entropy of a sequence of segment classifications.

13. The fetal monitoring system of claim 1, wherein the clinical indicator determined by the clinical condition detector includes an indicator of a fetal condition.

14. The fetal monitoring system of claim 1, wherein the clinical indicator determined by the clinical condition detector includes an indicator of at least one of chorioamnionitis, preeclampsia, inflammation, infection, hypoxia, hypoxemia, metabolic acidosis, and fetal cardiac arrhythmias.

15. The fetal monitoring system of claim 1, further comprising a signal selection unit coupled to the signal analyzer for selectively rejecting one or more of the acquired signals based on a quality of the acquired signals.

16. The fetal monitoring system of claim 2, wherein the display unit includes a computer screen.

17. The fetal monitoring system of claim 2, wherein the display unit includes a handheld device.

18. The fetal monitoring system of claim 17, further comprising a wireless transmitter for transmitting the output of the signal analyzer to the handheld device.

19. A fetal monitoring system comprising:

a data acquisition system for acquiring electrical signals, the data acquisition system including an electrode array having a plurality of electrodes attachable to a maternal abdominal region;

a signal analyzer for analyzing the acquired electrical signals, including;

obtaining information characterizing a fetal orientation according to a cardiac dipole model; and

determining the fetal orientation based on the obtained information; and

a display unit for generating a visual representation of the fetal orientation determined by the signal analyzer.

20. A method for fetal monitoring comprising:

acquiring electrical signals from a plurality of electrodes, including a plurality of electrodes applied to a maternal abdominal region;

analyzing the electrical signals, including performing a morphological analysis of fetal electrocardiogram signals;

determining a clinical indicator from a result of performing the morphological analysis.

21. The method of claim 20 wherein performing the morphological analysis includes determining a quantitative measure of morphological variation.

22. The method of claim 21 wherein determining the quantitative measure of morphological variation includes characterizing segments of signals determined from the acquired electrical signals according to a group of classes, and determining a measure of variation in sequences of segment classifications.

23. The method of claim 21 wherein the quantitative measure of morphological variation includes an entropy of a sequence of segment classifications.

24. The method of claim 20 wherein determining a clinical indicator includes determining an indicator of a fetal condition.

25. The method of claim 20 wherein determining a clinical indicator includes determining an indicator of an inflammation condition.

26. The method of claim 20 wherein determining a clinical indicator includes determining an indicator of at least one of chorioamnionitis, preeclampsia, inflammation, and infection.

27. A method for fetal monitoring comprising:

acquiring electrical signals from a plurality of electrodes, including a plurality of electrodes applied to a maternal abdominal region;

analyzing the electrical signals, including obtaining information characterizing a fetal orientation according to a cardiac dipole model; and

determining the fetal orientation based on the obtained information.

28. A method for fetal monitoring comprising:

acquiring electrical signals from a plurality of electrodes, including a plurality of electrodes applied to a maternal abdominal region;

analyzing the electrical signals, including obtaining information characterizing a muscle movement associated with uterine contraction; and

determining a characteristic of the uterine contraction based on the obtained information.