Application of High-flow Nasal Oxygen in Cesarean Section

Study Overview
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Brief Summary
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The study propose that the using the high-flow nasl oxygen to provide oxygen for maternal can improve the fetal acidemia and the neonatal outcomes during cesarean section with combined spinal-epidural anesthesia.

Detailed Description
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Maternal oxygen supplementation is widely used intrauterine resuscitation technique in clinical, which can improve fetal oxygenation and prevent fetal acidemia. The incidence of hypotension is high in cesarean section with combined spinal-epidural anesthesia. Hypotension contributes to insufficient perfusion of uterus and placenta, resulting in decreased fetal oxygen supply and neonatal acidemia. High flow nasal oxygen have a better improvement oxygenation of patients by providing high flow oxygen airflow with heating and humidification through nasal cannula.

Official Title
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Effect of Maternal Oxygen Supplementation by High-flow Nasal Oxygen Compared With Room Air on Fetal Acidemia

Conditions
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Fetal Acidemia

Intervention / Treatment
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* Device: Optiflow high-flow nasal cannula system


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: An elective cesarean section in Beijing Tongren Hospital ≥37 weeks' gestation American society of Aneshesiologists（ASA） I-III Aged 18 to 45 years old The fasting time is 6-8h, and the water restriction time is ≥2h Anesthesia: combined spinal-epidural anesthesia Agree to the study and sign the informed consent Exclusion Criteria: Fetal or placental abnormalities are known Maternal has complications Maternal BMI ≥40 kg/m2 History of difficult intubation or known difficult airway Contraindications for HFNO such as nasal lesions or structural changes Gastric reflux disease

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: air group<br>the patients of the air group receive the 2L/min with air pattern by the Optiflow high-flow nasal cannula system from anesthesia to fetal delivery. | |
| Experimental: HFNO group<br>For HFNO group, a flow rate of 40L/min, with 100% oxygen concentration and a temperature of 37℃ by the Optiflow high-flow nasal cannula system from anesthesia to fetal delivery. | Device: Optiflow high-flow nasal cannula system<br>* Using the Optiflow high-flow nasal cannula system to supply oxygen for maternal.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| umbilical artery lactate, mmol/L | mmol/L | the fetal delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| umbilical artery pH value | unitless | the fetal delivery | 
| umbilical artery oxygen partial pressure(PO2) | mmHg | the fetal delivery | 
| umbilical artery partial pressure of carbon dioxide(PCO2) | mmHg | the fetal delivery | 
| umbilical artery base excess(BE), mmol/L | mmol/L | the fetal delivery | 
| the incidence of pH<7.20 and pH<7.10 | percentage | the fetal delivery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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high-flow nasal oxygen, cesarean section, oxygen, umbilical artery, acidemia