[Determination of intrauterine pressure using catheter-tip transducer inserted outside fetal membranes].
To determining intrauterine pressure outside fetal membranes, we used a catheter-tip transducer to study 20 women before the occurrence membrane rupture. Their mean age was 28.2 +/- 3.4 years and all women were in weeks 37 to 41 of pregnancy when studied. In the first stage of labor, the peak intrauterine pressure was 60.0 +/- 12.5 mmHg (mean +/- SD) when the external os was dilated 4 to 6 cm, 90.0 +/- 14.8 mmHg, at 7 to 8 cm dilation, and 80.0 +/- 11.5 mmHg at 9 cm or greater dilation. Each pressure wave lasted 45 to 55 sec. The highest baseline pressure (28.0 +/- 4.5 mmHg) was obtained when the subjects were sitting. A baseline pressure of 17.0 +/- 4.0 mmHg was obtained in the supine position, as well as a value of 21.0 +/- 3.5 mmHg in the recumbent position. There were no complications related to the catheter-tip transducer. Our findings indicate that this method is both accurate and reliable in determining the amounts of intrauterine pressure to which fetal membranes are subjected.
Yagami
H
H
Department of Obstetrics and Gynecology, Kakegawa Municipal General Hospital, Shizuoka.
Kurauchi
O
O
Furui
T
T
Ohno
Y
Y
Ando
H
H
Nomura
S
S
Tanamura
A
A
Mizutani
S
S
Tomoda
Y
Y
Kasugai
M
M
D000328:Adult; D002404:Catheterization; D005321:Extraembryonic Membranes / Q000502:physiology; D005260:Female; D006801:Humans; D007743:Labor, Obstetric / Q000502:physiology*; D008722:Methods; D011247:Pregnancy; D014160:Transducers, Pressure; D014590:Uterine Contraction / Q000502:physiology*