Effect of Ephedrine vs. Norepinephrine on Prevention of Fetal Acidosis During Cesarean Section Under Spinal Anesthesia (NEO-FET)

Effect of Ephedrine and Norepinephrine on Fetal Acidosis During Cesarean Section Under Spinal Anesthesia: A Prospective, Randomized Controlled Trial

This study compares the effects of two medications, ephedrine and norepinephrine, on the baby (fetus) when used to treat low blood pressure (hypotension) during cesarean section under spinal anesthesia. Hypotension is a common side effect during spinal anesthesia, and it can affect the blood flow to the baby. Both medications are commonly used to manage this condition. The goal of the study is to determine which medication is more effective and safer for the baby, by measuring the pH level in the umbilical artery after birth. The study will also examine maternal blood pressure, heart rate, and the baby's Apgar scores.

Study Overview

• Status: Completed
• Conditions: Acidosis; Cesarean Delivery Affecting Newborn; Maternal Hypotension; Spinal Aneshtesia
• Intervention / Treatment: Drug: Ephedrine; Drug: Norepinephrine

Detailed Description

This is a prospective, randomized, double-blind, controlled clinical trial designed to compare the effects of ephedrine and norepinephrine on fetal acidosis during cesarean section performed under spinal anesthesia. Maternal hypotension is a frequent complication associated with spinal anesthesia, and the management of this condition is critical for maintaining adequate uteroplacental perfusion. While both ephedrine and norepinephrine are commonly used vasopressors, there is ongoing debate regarding their relative safety and efficacy, particularly in terms of fetal outcomes.

The primary aim of this study is to evaluate the incidence of fetal acidosis, defined as an umbilical artery pH < 7.20, in patients receiving either ephedrine or norepinephrine. Secondary outcomes include maternal blood pressure control, heart rate, incidence of maternal and fetal tachycardia, Apgar scores at 1 and 5 minutes, and the need for additional vasopressor support. A total of 100 pregnant women undergoing elective cesarean section will be enrolled, with 50 participants in each treatment group. All participants will receive standardized spinal anesthesia, and vasopressors will be titrated according to protocol.

The study is designed to inform clinical decision-making regarding optimal vasopressor selection in obstetric anesthesia, with a focus on balancing maternal hemodynamic stability and fetal well-being.

• Study Type: Interventional
• Enrollment (Actual): 102
• Phase: Phase 4

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Diyarbakır, Turkey (Türkiye), 21070
    • SBÜ Gazi Yaşargil Eğitim ve Araştırma Hastanesi

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Pregnant women aged between 18 and 45 years
• Singleton pregnancy at ≥ 37 weeks of gestation
• Scheduled for elective cesarean section under spinal anesthesia
• ASA (American Society of Anesthesiologists) physical status classification I or II
• Ability to understand and sign the informed consent form

Exclusion Criteria:

• History of allergy or hypersensitivity to ephedrine or norepinephrine
• Multiple gestation pregnancies
• Diagnosis of pre-eclampsia, eclampsia, or other hypertensive disorders of pregnancy
• Known cardiovascular disease or arrhythmia
• Placental abnormalities (e.g., placenta previa, placental abruption)
• Fetal structural or chromosomal anomalies
• Morbid obesity (BMI > 40 kg/m²)
• Refusal to participate or inability to provide informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Ephedrine Group; Participants in this group will receive intravenous bolus doses of ephedrine (5-10 mg) to manage spinal anesthesia-induced hypotension during cesarean section.	Drug: Ephedrine; Intravenous bolus of 5-10 mg ephedrine administered as needed to treat maternal hypotension following spinal anesthesia during elective cesarean section. The drug is prepared in identical, unlabeled syringes to ensure blinding.; Other Names: Ephedrine hydrochloride
Experimental: Norepinephrine Group; Participants in this group will receive intravenous bolus doses of norepinephrine (5-10 µg) to manage spinal anesthesia-induced hypotension during cesarean section.	Drug: Norepinephrine; Intravenous bolus of norepinephrine (5-10 µg) to treat spinal anesthesia-induced hypotension during cesarean section.; Other Names: Steradin®

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of fetal acidosis (umbilical artery pH < 7.20)	Fetal acidosis is defined as an umbilical artery blood pH < 7.20. Arterial blood will be collected from a double-clamped segment of the umbilical cord immediately after delivery and analyzed using a validated blood gas analyzer.	Within 5 minutes after birth

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of maternal tachycardia	Maternal tachycardia is defined as a heart rate greater than 100 bpm recorded after vasopressor administration. Heart rate is continuously monitored using ECG. The outcome is the proportion of participants with tachycardia.	During surgery
Incidence of maternal hypotension	Defined as a decrease in systolic blood pressure >20% from baseline or <90 mmHg. Non-invasive blood pressure is monitored continuously.	Within 30 minutes post-spinal anesthesia

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of fetal tachycardia	Fetal tachycardia is defined as a fetal heart rate greater than 160 bpm, assessed using cardiotocography prior to delivery. The outcome is the proportion of fetuses with tachycardia	At delivery
Apgar score at 1 minute	Apgar Score (Appearance, Pulse, Grimace, Activity, Respiration) will be assessed by the attending neonatologist. The score ranges from 0 to 10, where higher scores indicate better neonatal condition. The outcome is the distribution of Apgar scores at 1 minute after birth.	At 1 minute after delivery
Apgar score at 5 minutes	Apgar Score (Appearance, Pulse, Grimace, Activity, Respiration) will be assessed by the attending neonatologist. The score ranges from 0 to 10, where higher scores indicate better neonatal condition. The outcome is the distribution of Apgar scores at 5 minutes after birth.	At 5 minutes after delivery
Requirement for additional vasopressor doses	The number and total dosage of additional vasopressor boluses (ephedrine in mg or norepinephrine in µg) required after the initial dose will be recorded for each participant.	During surgery

Collaborators and Investigators

• Sponsor: mehmet özkılıç
• Investigators: Principal Investigator: Mehmet ÖZKILIÇ, Anesthesiology and Intensive Care Specialist, MD, Gazi Yaşargil Training and Research Hospital

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2025
• Primary Completion (Actual): December 12, 2025
• Study Completion (Actual): December 15, 2025

Study Registration Dates

• First Submitted: April 1, 2025
• First Submitted That Met QC Criteria: April 8, 2025
• First Posted (Actual): April 10, 2025

Study Record Updates

• Last Update Posted (Actual): December 29, 2025
• Last Update Submitted That Met QC Criteria: December 26, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Norepinephrine; Ephedrine; Fetal Acidosis; Maternal Hypotension
• Additional Relevant MeSH Terms: Metabolic Diseases; Acid-Base Imbalance; Nutritional and Metabolic Diseases; Acidosis; Organic Chemicals; Hydrocarbons; Hydrocarbons, Cyclic; Hydrocarbons, Aromatic; Amines; Catechols; Phenols; Benzene Derivatives; Alcohols; Propanolamines; Amino Alcohols; Propanols; Ethanolamines; Phenethylamines; Ethylamines; Biogenic Monoamines; Biogenic Amines; Catecholamines; Norepinephrine; Ephedrine
• Other Study ID Numbers: GYEAH-OB-NE-EF-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD will not be shared because data sharing was not included in the approved study protocol.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No