Abstract：
Hyperoxygenation has shown promise in improving suspicious fetal heart patterns in women in labor. However, the effect of hyperoxygenation on neonatal outcomes in women in labor with pathologic fetal heart rate tracing has not been studied.
This study aimed to evaluate the effect of fractional inspiration of oxygen of 80% compared with fractional inspiration of oxygen of 40% on neonatal outcomes in women with pathologic fetal heart rate tracing.
This randomized, open-label, parallel arm, outcome assessor-blinded clinical trial was conducted in a large tertiary care university hospital. Singleton parturients aged ≥18 years at term gestation in active labor (cervical dilatation of ≥6 cm) with pathologic fetal heart rate tracing were recruited in the study. Pathologic fetal heart rate tracing was defined according to the International Federation of Gynecology and Obstetrics 2015 guidelines. The International Federation of Gynecology and Obstetrics classifies fetal heart rate tracings into 3 categories (normal, suspicious, and pathologic) based on rate, variability, and deceleration. Women in the intervention arm received oxygen at 10 L/min via a nonrebreathing mask, and those in the usual care arm received oxygen at 6 L/min with a simple face mask. Oxygen supplementation was continued until cord clamping. The primary outcome measure was a 5-minute Apgar score. The secondary outcome measures were the proportion of neonatal intensive care unit admission, umbilical cord blood gas variables, level of methyl malondialdehyde in the cord blood, and mode of delivery.
Overall, 148 women (74 women in the high fractional inspiration of oxygen arm and 74 in the low fractional inspiration of oxygen arm) with pathologic fetal heart rate tracing were analyzed. The demographic data, obstetrical profiles, and comorbidities were comparable. The median 5-minute Apgar scores were 9 (interquartile range, 8-10) in the hyperoxygenation arm and 9 (interquartile range, 8-10) in the usual care arm (P=.12). Furthermore, the rate of neonatal intensive care unit admission (9.5% vs 12.2%; P=.6) and the requirement of positive pressure ventilation (6.8% vs 8.1%; P=.75) were comparable. Concerning cord blood gas parameters, the hyperoxygenation arm had a significantly higher base deficit in the umbilical vein and lactate level in the umbilical artery. The cesarean delivery rate was significantly lower in women who received hyperoxygenation (4.1% [3/74]) than in women who received normal oxygen supplementation (25.7% [19/74]) (P=.00). In addition, umbilical vein malondialdehyde level in the umbilical vein was lower in the hyperoxygenation group (8.28±4.65 μmol/L) than in the normal oxygen supplementation group (13.44±8.34 μmol/L) (P=.00).
Hyperoxygenation did not improve the neonatal Apgar score in women with pathologic fetal heart rate tracing. In addition, neonatal intensive care unit admission rate and blood gas parameters remained comparable. Therefore, the results of this trial suggest that a high fractional inspiration of oxygen supplementation confers no benefit on neonatal outcomes in women with pathologic fetal heart rate tracings and normal oxygen saturation.
This study aimed to evaluate the effect of fractional inspiration of oxygen of 80% compared with fractional inspiration of oxygen of 40% on neonatal outcomes in women with pathologic fetal heart rate tracing.
This randomized, open-label, parallel arm, outcome assessor-blinded clinical trial was conducted in a large tertiary care university hospital. Singleton parturients aged ≥18 years at term gestation in active labor (cervical dilatation of ≥6 cm) with pathologic fetal heart rate tracing were recruited in the study. Pathologic fetal heart rate tracing was defined according to the International Federation of Gynecology and Obstetrics 2015 guidelines. The International Federation of Gynecology and Obstetrics classifies fetal heart rate tracings into 3 categories (normal, suspicious, and pathologic) based on rate, variability, and deceleration. Women in the intervention arm received oxygen at 10 L/min via a nonrebreathing mask, and those in the usual care arm received oxygen at 6 L/min with a simple face mask. Oxygen supplementation was continued until cord clamping. The primary outcome measure was a 5-minute Apgar score. The secondary outcome measures were the proportion of neonatal intensive care unit admission, umbilical cord blood gas variables, level of methyl malondialdehyde in the cord blood, and mode of delivery.
Overall, 148 women (74 women in the high fractional inspiration of oxygen arm and 74 in the low fractional inspiration of oxygen arm) with pathologic fetal heart rate tracing were analyzed. The demographic data, obstetrical profiles, and comorbidities were comparable. The median 5-minute Apgar scores were 9 (interquartile range, 8-10) in the hyperoxygenation arm and 9 (interquartile range, 8-10) in the usual care arm (P=.12). Furthermore, the rate of neonatal intensive care unit admission (9.5% vs 12.2%; P=.6) and the requirement of positive pressure ventilation (6.8% vs 8.1%; P=.75) were comparable. Concerning cord blood gas parameters, the hyperoxygenation arm had a significantly higher base deficit in the umbilical vein and lactate level in the umbilical artery. The cesarean delivery rate was significantly lower in women who received hyperoxygenation (4.1% [3/74]) than in women who received normal oxygen supplementation (25.7% [19/74]) (P=.00). In addition, umbilical vein malondialdehyde level in the umbilical vein was lower in the hyperoxygenation group (8.28±4.65 μmol/L) than in the normal oxygen supplementation group (13.44±8.34 μmol/L) (P=.00).
Hyperoxygenation did not improve the neonatal Apgar score in women with pathologic fetal heart rate tracing. In addition, neonatal intensive care unit admission rate and blood gas parameters remained comparable. Therefore, the results of this trial suggest that a high fractional inspiration of oxygen supplementation confers no benefit on neonatal outcomes in women with pathologic fetal heart rate tracings and normal oxygen saturation.
摘要：
背景：高氧合已显示出改善分娩妇女可疑胎儿心脏模式的前景。然而,在病理性胎心率追踪的产程中，高氧对新生儿结局的影响尚未被研究。
目的：本研究旨在评估80%的FiO2（氧气部分吸入）与40%的FiO2对病理性胎心率追踪妇女新生儿结局的影响。
方法：这是随机的，开放标签，平行臂，结局评估者盲法临床试验在一家大型三级护理大学医院进行.本研究招募了积极分娩（宫颈扩张≥6cm）的足月妊娠≥18岁的单胎产妇，并进行了病理性胎儿心率追踪。根据FIGO2015指南定义病理性胎儿心率追踪。FIGO将胎儿心率描记分为三类(正常，可疑和病理)基于速率，可变性和减速。干预组的女性通过非再呼吸面罩以10升/分钟的速度接受氧气，和那些在常规护理臂接受氧气在6升/分钟与一个简单的面罩。持续补充氧气直到脐带夹紧。主要结果测量是5分钟的APGAR评分。次要结局指标是新生儿重症监护病房（NICU）的住院比例，脐带血气变量，脐带血中甲基丙二醛的水平和分娩方式。
结果：分析了148名具有病理性胎儿心率追踪的妇女（高FiO2臂中的74名妇女和低FiO2臂中的74名妇女）。人口统计数据，产科资料和合并症具有可比性。5分钟的中位数（范围）APGAR评分为9（8-10）和9（8-10），分别在充氧和常规护理臂中（p=0.12）。此外，NICU入院率（9.46％vs12.16％；p=0.6），正压通气的需求(6.8%vs8.1%;p=0.75)具有可比性.在脐带血气体参数中，高氧组的脐静脉和脐动脉中的乳酸含量明显较高.接受高氧合的妇女的剖腹产率显着降低（3/74；4.1％vs19/74；25.7％；p=0.00）。此外,高氧组脐静脉丙二醛水平较低(8.28±4.65μmol/Lvs13.44±8.34μmol/L;p=0.00)。
结论：高氧合并不能改善病理性胎心率追踪妇女的新生儿APGAR评分。此外,NICU入院率和血气参数保持可比性。因此,本试验的结果表明,对于病理性胎儿心率描记和正常血氧饱和度的女性,高分数的氧气补充对新生儿结局没有益处.
目的：本研究旨在评估80%的FiO2（氧气部分吸入）与40%的FiO2对病理性胎心率追踪妇女新生儿结局的影响。
方法：这是随机的，开放标签，平行臂，结局评估者盲法临床试验在一家大型三级护理大学医院进行.本研究招募了积极分娩（宫颈扩张≥6cm）的足月妊娠≥18岁的单胎产妇，并进行了病理性胎儿心率追踪。根据FIGO2015指南定义病理性胎儿心率追踪。FIGO将胎儿心率描记分为三类(正常，可疑和病理)基于速率，可变性和减速。干预组的女性通过非再呼吸面罩以10升/分钟的速度接受氧气，和那些在常规护理臂接受氧气在6升/分钟与一个简单的面罩。持续补充氧气直到脐带夹紧。主要结果测量是5分钟的APGAR评分。次要结局指标是新生儿重症监护病房（NICU）的住院比例，脐带血气变量，脐带血中甲基丙二醛的水平和分娩方式。
结果：分析了148名具有病理性胎儿心率追踪的妇女（高FiO2臂中的74名妇女和低FiO2臂中的74名妇女）。人口统计数据，产科资料和合并症具有可比性。5分钟的中位数（范围）APGAR评分为9（8-10）和9（8-10），分别在充氧和常规护理臂中（p=0.12）。此外，NICU入院率（9.46％vs12.16％；p=0.6），正压通气的需求(6.8%vs8.1%;p=0.75)具有可比性.在脐带血气体参数中，高氧组的脐静脉和脐动脉中的乳酸含量明显较高.接受高氧合的妇女的剖腹产率显着降低（3/74；4.1％vs19/74；25.7％；p=0.00）。此外,高氧组脐静脉丙二醛水平较低(8.28±4.65μmol/Lvs13.44±8.34μmol/L;p=0.00)。
结论：高氧合并不能改善病理性胎心率追踪妇女的新生儿APGAR评分。此外,NICU入院率和血气参数保持可比性。因此,本试验的结果表明,对于病理性胎儿心率描记和正常血氧饱和度的女性,高分数的氧气补充对新生儿结局没有益处.
