Tissue oxygen saturation levels from fetus to neonate.
OBJECTIVE
Oxygen saturation during the term of delivery to the first cry, when fetal circulation dynamically changes, has not yet been examined. The aim of this study was therefore to determine whether the continuous measurement of regional tissue oxygen saturation (rSO2) from crowning until 5 min after delivery is possible using fetal tissue oximetry with a sensor attached to the examiner's finger.


METHODS
Oxygen saturation levels in fetal cranial tissue between the second stage of delivery to crowning and up to 5 min after delivery were measured using fetal tissue oximetry with a sensor attached to the examiner's finger. Thirty-five deliveries were examined, and oxygen saturation was measured in seven infants from delivery of the head until 5 min after birth. Umbilical cord blood gas was measured in all cases. This clinical test was performed under the permission of the Ethics Committee of Hamamatsu University School of Medicine.


RESULTS
Average tissue oxygen saturation in the second stage of delivery and at 5 min after delivery were 50.3 ± 16.3% and 56.8 ± 8.46%, respectively. In cases of continuous measurement, average rSO2for crowning, immediately after delivery, and the first cry was 32.7 ± 9.5%, 30.0 ± 6.6%, and 31.6 ± 5.5%, respectively.


CONCLUSIONS
We herein successfully measured oxygen saturation levels in fetal cranial tissue during crowning, delivery of the head, the first cry, and 5 min after delivery using fetal tissue oximetry with a sensor attached to the examiner's finger.
Department of Obstetrics and Gynecology, Hamamatsu University School of Medicine, Hamamatsu Shizuoka, Japan.
Mari
M
Mukai
Department of Obstetrics and Gynecology, Hamamatsu University School of Medicine, Hamamatsu Shizuoka, Japan.
Toshiyuki
T
Uchida
Department of Obstetrics and Gynecology, Hamamatsu University School of Medicine, Hamamatsu Shizuoka, Japan.
Hiroaki
H
Itoh
ASTEM, Kawasaki, Kanagawa, Japan.
Hikaru
H
Suzuki
Department of Electrical and Electronics Engineering, Shizuoka University, Shizuoka, Japan.|Research Institute of Electronics, Shizuoka University, Shizuoka, Japan.
Masatsugu
M
Niwayama
Department of Obstetrics and Gynecology, Hamamatsu University School of Medicine, Hamamatsu Shizuoka, Japan.
Naohiro
N
Kanayama
D036861:Delivery, Obstetric; D005260:Female; D005323:Fetal Monitoring / Q000379:methods*; D005333:Fetus / Q000378:metabolism*; D006801:Humans; D007231:Infant, Newborn / Q000378:metabolism*; D008297:Male; D010092:Oximetry / Q000379:methods*; D010101:Oxygen Consumption / Q000502:physiology*; D012535:Scalp / Q000098:blood supply
fetal tissue oximetry; fetal tissue oxygen saturation; near-infrared spectroscopy; newborn; parturition