Ephedrine Doses to Prevent Maternal Hypotension After Spinal Anesthesia in Cesarean Section

A Randomized Controlled Trial Comparing the Effectiveness of Different Doses of Ephedrine Infusion in Preventing Maternal Hypotension Following Spinal Anesthesia for Caesarean Section

This randomized controlled trial aims to compare the effectiveness of different doses of ephedrine infusion in preventing maternal hypotension following spinal anesthesia in parturients undergoing cesarean sections. The study includes 120 participants, aged 18-40 years, with American Society of Anesthesiologists (ASA) physical status II, who are scheduled for elective cesarean delivery. The primary objective is to determine whether low-dose ephedrine infusions at 1.25 mg/min or 1.5 mg/min effectively reduce the incidence of maternal hypotension, with secondary outcomes assessing the need for rescue ephedrine, incidence of side effects (nausea, vomiting, tachycardia), and neonatal Apgar scores. Researchers will compare three groups-saline, 1.25 mg/min ephedrine, and 1.5 mg/min ephedrine-to evaluate their impact on maternal hemodynamic stability.

Study Overview

• Status: Completed
• Conditions: Hypotension After Spinal Anesthesia; Hypotension During Cesarean Delivery
• Intervention / Treatment: Drug: Normal Saline (Placebo); Drug: Ephedrine

• Study Type: Interventional
• Enrollment (Actual): 120
• Phase: Phase 4

Contacts and Locations

Study Locations

• Nepal
  • Dharan, Nepal
    • B.P. Koirala Institute of Health Sciences

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Patients undergoing cesarean section
• Self-identified as female
• American Society of Anesthesiologists (ASA) physical status II
• Aged between 18 to 40 years
• Full-term singleton pregnancies planned for cesarean delivery under spinal anesthesia

Exclusion Criteria:

• Body mass index (BMI) ≥ 40 kg/m²
• Height less than 145 cm
• Presence of severe neurological or psychiatric conditions
• History of pre-eclampsia
• Severe renal or metabolic disorders
• Contraindications to spinal anesthesia
• Antenatal evidence of fetal anomalies
• Cases with severely compromised fetuses requiring immediate general anesthesia
• Baseline systolic blood pressure (SBP) less than 90 mm Hg
• Pregnancy-induced hypertension
• Refusal to provide written consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Group A who received normal saline immediately after the administration of the; Participants in this group received normal saline immediately after the administration of the subarachnoid block (spinal anesthesia). This group serves as the control group to compare the effectiveness of ephedrine against no pharmacologic intervention	Drug: Normal Saline (Placebo); Participants in the control group receive a continuous intravenous infusion of normal saline, which serves as an inert placebo with no pharmacological effect. This intervention mimics the administration of the active treatments, allowing for direct comparison with the ephedrine groups to assess the effectiveness of the drug in preventing maternal hypotension during spinal anesthesia.
Experimental: Group B who received ephedrine at a dosage of 1.25 mg/min immediately after the subarachnoid block; Participants in this group received ephedrine at a dosage of 1.25 mg/min immediately after the subarachnoid block. This dose is intended to prevent maternal hypotension by maintaining blood pressure during spinal anesthesia.	Drug: Ephedrine; The interventions in this study include a control group receiving normal saline, which serves as an inert placebo to assess the effectiveness of the active treatments. Participants in Group B receive an ephedrine infusion at 1.25 mg/min, while those in Group C receive a higher dosage of 1.5 mg/min. This design allows for direct comparison of the two dosages of ephedrine against the control, enabling evaluation of their effectiveness in preventing maternal hypotension following spinal anesthesia during cesarean sections.
Experimental: Group C who received ephedrine at a dosage of 1.5 mg/min immediately after the subarachnoid block; Participants in this group received ephedrine at a higher dosage of 1.5 mg/min immediately following the subarachnoid block. This intervention tests whether a slightly higher dose of ephedrine provides better prevention of maternal hypotension without increasing side effects.	Drug: Ephedrine; The interventions in this study include a control group receiving normal saline, which serves as an inert placebo to assess the effectiveness of the active treatments. Participants in Group B receive an ephedrine infusion at 1.25 mg/min, while those in Group C receive a higher dosage of 1.5 mg/min. This design allows for direct comparison of the two dosages of ephedrine against the control, enabling evaluation of their effectiveness in preventing maternal hypotension following spinal anesthesia during cesarean sections.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Hypotension in Patients Undergoing Cesarean Section Following Spinal Anesthesia.	The primary outcome of the study is the incidence of maternal hypotension, defined as a decrease in systolic blood pressure (SBP) by more than 20% from baseline, in patients who received different doses of ephedrine (1.25 mg/min or 1.5 mg/min) or saline infusion following spinal anesthesia for cesarean section.	Hypotension episodes were monitored and recorded intraoperatively, immediately following the administration of spinal anesthesia until the end of the cesarean section procedure. The time frame for evaluating this outcome was during the surgical procedure

Collaborators and Investigators

• Sponsor: B.P. Koirala Institute of Health Sciences

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2020
• Primary Completion (Actual): August 1, 2021
• Study Completion (Actual): February 15, 2022

Study Registration Dates

• First Submitted: October 30, 2024
• First Submitted That Met QC Criteria: October 30, 2024
• First Posted (Actual): October 31, 2024

Study Record Updates

• Last Update Posted (Actual): October 31, 2024
• Last Update Submitted That Met QC Criteria: October 30, 2024
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypotension; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Autonomic Agents; Peripheral Nervous System Agents; Neurotransmitter Agents; Adrenergic Agents; Respiratory System Agents; Anti-Asthmatic Agents; Central Nervous System Stimulants; Bronchodilator Agents; Sympathomimetics; Vasoconstrictor Agents; Nasal Decongestants; Ephedrine; Pseudoephedrine
• Other Study ID Numbers: IRC/1598/019

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual participant data will be made available to researchers upon request. The data will be shared in a de-identified format to protect participant confidentiality.

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