Fetal monitoring during labor
First Claim
1. An apparatus for monitoring fetal health during labor comprising:
- means for continually sampling the electrocardiogram of a fetus and for continually outputting sampled signals; and
processing means for receiving said output sampled signals and in response thereto deriving signals representative of the P-R interval of the fetal heart, for repeatedly deriving a signal representative of the fetal heart rate, and for obtaining an indication relationship between directions of change, of the P-R interval and in the fetal heart rate or a repetition period of the fetal heart, for providing an indication of fetal health whereby an indication is given of shortening or lengthening of the P-R interval as the fetal heart rate increases or decreases.
2 Assignments
0 Petitions
Accused Products
Abstract
Apparatus for monitoring fetal health during labor detects the occurrence of a fetal ECG in digital signals derived from electrodes on a fetus using a matched filter routine to detect a QRS complex. The peaks of successive R waves are then found and used to determine fetal heart rate. After time coherent filtering of digital samples representing the fetal ECG the P-R interval and the elevation of the S-T interval are found and a correlation coefficient between the fetal heart rate and the P-R interval is derived. The elevation and the coefficient are displayed. If the correlation coefficient becomes positive for about half an hour and a significant fall in the elevation of the S-T interval also occurs it is an indication of acidosis of the fetus.
89 Citations
24 Claims
-
1. An apparatus for monitoring fetal health during labor comprising:
-
means for continually sampling the electrocardiogram of a fetus and for continually outputting sampled signals; and processing means for receiving said output sampled signals and in response thereto deriving signals representative of the P-R interval of the fetal heart, for repeatedly deriving a signal representative of the fetal heart rate, and for obtaining an indication relationship between directions of change, of the P-R interval and in the fetal heart rate or a repetition period of the fetal heart, for providing an indication of fetal health whereby an indication is given of shortening or lengthening of the P-R interval as the fetal heart rate increases or decreases. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
- 15. A method of monitoring fetal health during labor comprising repeatedly obtaining a signal representative of the P-R interval of the fetal heart, repeatedly obtaining a signal representative of the fetal heart rate, and providing an indication of relationship between directions of change, of the P-R interval and in the fetal heart rate or a repetition period of the fetal heart to provide an indication of fetal health whereby an indication is given of shortening or lengthening of the P-R interval as the fetal heart rate increases or decreases.
Specification