Effect of Oxytocin Bolus Versus Slow Infusion on Haemodynamic Stability During Caesarean Section Under Spinal Anaesthesia

NCT07784478 | Not Yet Recruiting

• 1 other identifier: CHR-IREB-2026-0050
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This study compares two standard ways of giving oxytocin (a medicine that helps the uterus contract) after the baby is born during a planned caesarean section performed under spinal anaesthesia. One group of women will receive oxytocin as a quick injection into the vein. The other group will receive the same dose of oxytocin as a slow infusion over 15 minutes. The researchers want to find out which method causes less drop in blood pressure and other heart-related changes, while still providing good contraction of the uterus and preventing excessive bleeding.

Conditions

Cesarean Section; Hypotension; Postpartum Hemorrhage; Spinal Anesthesia

Keywords

Oxytocin; Bolus; Infusion; Haemodynamic stability; Elective caesarean section; Spinal anaesthesia; Uterine tone; Vasopressor

Outcome Measures

Primary Outcomes (1)

• Change in Systolic Blood Pressure (SBP) from Baseline

  Change in systolic blood pressure from baseline (mean of three pre-anaesthesia readings) measured at 2, 5, and 10 minutes after oxytocin administration.

  Baseline; 2 minutes, 5 minutes, and 10 minutes after oxytocin administration

Secondary Outcomes (3)

• Change in Diastolic Blood Pressure and Heart Rate from Baseline

  1, 2, 3, 5, 10, 15, and 20 minutes after oxytocin administration

• Incidence of Clinically Significant Hypotension

  Within 20 minutes after oxytocin administration

• Uterine Contraction Scale Score

  5 minutes after placental delivery

Study Arms (2)

Bolus Group

ACTIVE COMPARATOR

Participants will receive oxytocin 5 IU in 1 mL normal saline as an intravenous bolus over 15 seconds immediately after umbilical cord clamping, followed by 9 mL normal saline infusion over 15 minutes (to maintain blinding).

Drug: Oxytocin

Infusion Group

EXPERIMENTAL

Participants will receive oxytocin 5 IU diluted in 50 mL normal saline administered via syringe pump over 15 minutes immediately after umbilical cord clamping. A simultaneous 1 mL normal saline bolus will be given over 15 seconds to maintain blinding of the initial injection.

Drug: Oxytocin

Interventions

Oxytocin DRUG

Oxytocin 5 IU administered either as a rapid intravenous bolus over 15 seconds or as a slow intravenous infusion over 15 minutes immediately after umbilical cord clamping during elective caesarean section under spinal anaesthesia.

Also known as: Syntocinon

Bolus Group; Infusion Group

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Adult female patients aged 18 to 40 years
• American Society of Anesthesiologists (ASA) physical status class I or II
• Singleton pregnancy at 37 to 42 weeks gestational age
• Scheduled for elective caesarean section under spinal anaesthesia
• Written informed consent obtained

You may not qualify if:

• Patients with anticipated hemodynamic instability including severe preeclampsia/eclampsia, placenta previa with active bleeding, placental abruption, or hemorrhagic shock
• Pre-existing cardiovascular disease including ischemic heart disease, valvular heart disease, cardiomyopathy, or arrhythmias
• Baseline systolic blood pressure \< 100 mmHg or heart rate \> 100 bpm before spinal block
• Known hypersensitivity to oxytocin
• Failed spinal anaesthesia requiring conversion to general anaesthesia
• Patients receiving medications that may alter the hemodynamic response to oxytocin (beta-blockers, calcium channel blockers, ACE inhibitors, or angiotensin receptor blockers)
• Pre-existing anaemia (Hb \< 8 g/dL)

Sponsors & Collaborators

• Khyber Girls Medical College: lead

Study Sites (1)

Hayatabad Medical Complex / Khyber Girls Medical College

Peshawar, Khyber Pakhtunkhwa, 25000, Pakistan

Location

MeSH Terms

Conditions

Hypotension; Postpartum Hemorrhage

Interventions

Oxytocin

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases; Obstetric Labor Complications; Pregnancy Complications; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Puerperal Disorders; Uterine Hemorrhage; Hemorrhage; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Pituitary Hormones, Posterior; Pituitary Hormones; Peptide Hormones; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Peptides; Amino Acids, Peptides, and Proteins

Central Study Contacts

Fareeha Zahir, MBBS / FCPS-II Trainee

CONTACT

+923319932275; fareehak933@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: Participants and the data collector (outcomes assessor) are blinded to group allocation. The anaesthetist administering the study drug cannot be blinded due to the different administration techniques (bolus versus infusion), but is not involved in data recording.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Two-group parallel randomised controlled trial comparing oxytocin bolus versus slow infusion.

Study Record Dates

• First Submitted: August 20, 2026
• First Posted: August 25, 2026
• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): April 1, 2027
• Last Updated: August 25, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

PA (1)