Epinephrine Infusion for Prophylaxis Against Maternal Hypotension After Spinal Anesthesia for Cesarean Delivery

Epinephrine Versus Phenylephrine Infusion for Prophylaxis Against Maternal Hypotension After Spinal Anesthesia for Cesarean Delivery: a Randomized Controlled Trial.

Subarachnoid block is the common route of anesthesia for cesarean delivery. Maternal hypotension after subarachnoid block is very common despite the vigorous methods for its prevention. Maternal hypotension is sometimes deleterious to the mother and the fetus; thus, it is highly recommended to use prophylactic vasopressors directly after the block and before the blood pressure drops. The aim of this work is to compare the maternal and neonatal effects of epinephrine and phenylephrine when used as prophylactic infusion after subarachnoid block for cesarean delivery.

Study Overview

• Status: Completed
• Conditions: Hypotension During Surgery
• Intervention / Treatment: Drug: Phenylephrine; Drug: Epinephrine

Detailed Description

Upon arrival to the operating room, routine monitoring will be applied (electrocardiography, pulse oximetry, and a non-invasive blood pressure monitor). Two 18G-cannula will be inserted, and 10 mg metoclopramide and 50 mg ranitidine will be delivered. Co-load infusion of lactated Ringer's solution will be infused at a rate of 15 mL/Kg over 10 minutes, and 10 mg hyperbaric bupivacaine in addition to 20 mcg fentanyl will be injected in the subarachnoid space at L3-L4 or L4-L5 interspace using 25G spinal needle.

After subarachnoid block, mothers will be placed in a supine position with left-lateral tilt and will receive the vasopressor infusion according to the allocated study group:

• Phenylephrine group (n=113): will receive phenylephrine infusion at rate of 0.4 mcg/Kg/min. (10 mg /1 mL) will be diluted to reach a final concentration of 10 mcg/mL(5).
• Epinephrine group (n=113): will receive epinephrine infusion dose of 0.03 mcg/Kg/min. epinephrine (1mg/ 1mL ampoule) will be diluted to reach a final concentration of 10 mcg/ml.

The prophylactic vasopressor infusion will be maintained until 5 minutes after delivery of the fetus

Hemodynamic management in both groups will be as follow:

Post-spinal hypotension (defined as systolic blood pressure ≤80% of the baseline reading during the period from intrathecal injection to delivery of the fetus) will be managed by either ephedrine 9 mg bolus (if the heart rate was below 75 bpm) or phenylephrine 50 mg bolus (if the heart rate was above 75 bpm).

Severe post-spinal hypotension (defined as systolic blood pressure ≤60% of the baseline reading) will be managed by administration of either ephedrine 15 mg (if the heart rate was below 75 bpm) or phenylephrine 100 mg bolus (if the heart rate was above 75 bpm).

Reactive hypertension (defined as systolic blood pressure ≥120% from the baseline reading) will be managed by stoppage of the infusion till the next systolic blood pressure reading. The infusion will be then re-started at a reduced rate (50% of the initial dose) when systolic blood pressure will have decreased to be within 20% of the baseline reading.

Intraoperative bradycardia (defined as a heart rate less than 55 bpm) will be managed by stoppage of the vasopressor infusion if not associated with hypotension. The infusion will be then re-started at a reduced rate (50%) when the heart rate is more than 55 bpm. IV atropine bolus (0.5 mg) will be administered if bradycardia persisted despite stoppage of the infusion. If accompanied with hypotension, bradycardia will be managed by IV bolus of ephedrine 9 mg.

Fluid administration will be continued up to a maximum of 1.5 liters. After delivery, an oxytocin bolus (0.5 IU) will be delivered over five seconds, followed by infusion at a rate of 2.5 IU/hour.

• Study Type: Interventional
• Enrollment (Actual): 196
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Egypt
  • Cairo, Egypt, 115711
    • Yasmin Ibrahim

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• full-term singleton pregnant women, admitted for elective cesarean delivery
• aged between 18 and 40 years

Exclusion Criteria:

• Patients with uncontrolled cardiac morbidities, hypertensive disorders of pregnancy
• Peripartum bleeding
• coagulation disorders
• Baseline systolic blood pressure (SBP) < 100 mmHg

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: epinephrine	Drug: Epinephrine; epinephrine infusion dose of 0.03 mcg/Kg/min. epinephrine (1mg/ 1mL ampoule) will be diluted to reach a final concentration of 10 mcg/ml.
Active Comparator: phenylephrine	Drug: Phenylephrine; phenylephrine infusion at rate of 0.4 mcg/Kg/min. (10 mg /1 mL) will be diluted to reach a final concentration of 10 mcg/mL

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
incidence of post spinal hypotension	systolic blood pressure ≤80% of the baseline reading during the period from intrathecal injection to delivery of the fetus	from spinal anesthesia till delivery of fetus (about 45-60 mins)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
incidence post spinal reactive hypertension	defined as systolic blood pressure ≥120% from the baseline reading	from spinal anesthesia till delivery of fetus (about 45-60 mins)
fetal outcome	arterial blood gas	at birth

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
bradycardia	heart rate less than 55 bpm	from spinal anesthesia till delivery of fetus (about 45-60 mins)
fetal outcome	APGAR score (Appearance - Pulse - Grimace - Activity -Respiration ) normal 7-10	at 1 min , and at 5 min

Collaborators and Investigators

• Sponsor: Cairo University

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2023
• Primary Completion (Actual): December 1, 2023
• Study Completion (Actual): December 1, 2023

Study Registration Dates

• First Submitted: March 26, 2023
• First Submitted That Met QC Criteria: May 20, 2023
• First Posted (Actual): May 31, 2023

Study Record Updates

• Last Update Posted (Actual): February 28, 2024
• Last Update Submitted That Met QC Criteria: February 25, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypotension; Physiological Effects of Drugs; Adrenergic Agents; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Autonomic Agents; Peripheral Nervous System Agents; Protective Agents; Adrenergic alpha-Agonists; Adrenergic Agonists; Cardiotonic Agents; Bronchodilator Agents; Anti-Asthmatic Agents; Respiratory System Agents; Adrenergic beta-Agonists; Sympathomimetics; Vasoconstrictor Agents; Mydriatics; Nasal Decongestants; Adrenergic alpha-1 Receptor Agonists; Epinephrine; Phenylephrine; Oxymetazoline
• Other Study ID Numbers: MD-245-2022

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No