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Aim: Although several studies reported the measurement of fetal oxygen saturation using fetal pulse oximetry (FPO) for evaluation of the fetal intrapartum condition, a systematic review of the seven randomized controlled trials (RCTs) provided no evidence to support FPO for intrapartum fetal monitoring. In the present review, we re‐evaluate an overview for the use of FPO and seven RCTs of FPO. Methods: We reviewed numerous previous reports on FPO and seven RCTs of intrapartum FPO. RCTs were conducted with the main outcome measure being a reduction in the cesarean section rate. Results: The largest trial with 5341 entries failed to show any reduction. The negative result from this RCT may be explained by the use of a different cutoff value for fetal oxygen saturation compared to the other RCT; in addition, there were differences in the indications for cesarean section due to dystocia and in the definition of non‐reassuring fetal status (NRFS). An abnormal FPO value, defined as the fetal oxygen saturation value <30% for at least 10 min, is useful for making a diagnosis of fetal acidosis. A newly developed device, an examiner's finger‐mounted tissue oximetry, accurately measures tissue oxygen saturation while overcoming the drawbacks of FPO, such as infection risk and slipping off of the sensor during descent of the fetal head. Conclusion: FPO (including the new device) with fetal heart rate monitoring in selected cases of NRFS may reduce the cesarean section rate. [ABSTRACT FROM AUTHOR]

Aim 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 rSO2 for crowning, immediately after delivery, and the first cry was 32.7 ± 9.5%, 30.0 ± 6.6%, and 31.6 ± 5.5%, respectively. Conclusion 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. [ABSTRACT FROM AUTHOR]

The article presents study to describe preliminary experience with a finger-mounted fetal tissue oximetry probe during the 2nd stage of labor. It mentions measurement of fetal tissue oxygen saturation by using a finger-mounted fetal tissue oximetry during cervical examinations. It reveals tissue oxygen saturation of the fetal head was obtained by finger-mounted fetal tissue oximetry.

Aim To measure cerebral tissue hemoglobin in uncomplicated and complicated pregnant women during the peripartum period. Methods Time-resolved spectroscopy ( TRS-20) can measure absolute concentration of oxygenated, deoxygenated, and total tissue hemoglobin based on the transit time of individual photons. Therefore, we used TRS-20 to measured tissue hemoglobin in the hemi-prefrontal lobes of normotensive pregnant women with ( n = 51) or without ( n = 19) epidural anesthesia, hypertensive pregnant women with pre-eclampsia ( n = 10), a pregnant woman with acute onset of hypertension soon after delivery, and a hypertensive woman after hemorrhagic stroke in delivery. Results Cyclic labor concomitant with intra-abdominal pressure caused synergistic elevation in cerebral tissue hemoglobin. In contrast, epidural anesthesia reduced the amplitude of the cyclic increase of cerebral tissue hemoglobin in normotensive pregnant women. Hypertension in labor due to pre-eclampsia increased the amplitude of synergistic elevation of cerebral tissue hemoglobin caused by cyclic labor and intra-abdominal pressure. A prolonged high basal level of cerebral tissue hemoglobin was observed in a case of acute onset of hypertension soon after delivery. A decrease in cerebral tissue hemoglobin in the hemi-prefrontal lobe was observed in a woman 2 h after the onset of hemorrhagic stroke in labor. Conclusions TRS-20 can detect specific changes in maternal cerebral tissue hemoglobin level in response to physiological and pathophysiological changes in delivery. Thus, it represents a promising new conventional tool for maternal cerebral monitoring in the peripartum period. [ABSTRACT FROM AUTHOR]