Magnesium Sulphate Versus Dexamethasone With TAP Block for Post-Cesarean Analgesia

NCT07773220 | Not Yet Recruiting

• 1 other identifier: 016/DME/KMC
• Study Type: interventional
• Target: 80
• Locations: 0 countries
• Sites: N/A

Brief Summary

This randomized, double-blind, controlled clinical trial will compare the effectiveness of a single intravenous dose of magnesium sulphate versus dexamethasone as an adjuvant to ultrasound-guided transversus abdominis plane (TAP) block for postoperative pain management after elective cesarean section. Eighty women undergoing elective lower-segment cesarean section under spinal anesthesia will be randomly allocated into two groups of 40 participants each. Group M will receive intravenous magnesium sulphate 50 mg/kg diluted in 100 mL normal saline, while Group D will receive intravenous dexamethasone 8 mg diluted in 100 mL normal saline. The study will assess postoperative pain using the Visual Analog Scale at 2, 4, 8, 12, and 24 hours after surgery, as well as duration of analgesia, rescue analgesic requirement, total tramadol consumption, and adverse effects. The study aims to determine whether either intravenous adjuvant provides more effective and prolonged postoperative analgesia when used with ultrasound-guided TAP block after cesarean section.

Conditions

Cesarean Section Complications

Keywords

postoperative pain; cesarean section

Outcome Measures

Primary Outcomes (1)

• Duration of analgesia

  Time from administration of the ultrasound-guided TAP block until the participant's first request for rescue analgesia, measured in minutes.

  From completion of the TAP block until the first request for rescue analgesia, assessed during the first 24 hours after cesarean section.

Study Arms (2)

Magnesium Sulphate Group

EXPERIMENTAL

Participants in this group will receive a single intravenous dose of magnesium sulphate 50 mg/kg diluted in 100 mL normal saline, administered 15 minutes before the ultrasound-guided TAP block. Following cesarean section, participants will receive a bilateral ultrasound-guided TAP block with 20 mL of 0.25% bupivacaine on each side.

Drug: Magnesium Sulphate 500 mg

Dexamethasone Group

ACTIVE COMPARATOR

Participants in this group will receive a single intravenous dose of dexamethasone 8 mg diluted in 100 mL normal saline, administered 15 minutes before the ultrasound-guided TAP block. Following cesarean section, participants will receive a bilateral ultrasound-guided TAP block with 20 mL of 0.25% bupivacaine on each side.

Drug: Dexamethasone

Interventions

Magnesium Sulphate 500 mg DRUG

Magnesium sulphate 50 mg/kg diluted in 100 mL normal saline, administered as a single intravenous dose 15 minutes before the ultrasound-guided TAP block.

Magnesium Sulphate Group

Dexamethasone DRUG

Dexamethasone 8 mg diluted in 100 mL normal saline, administered as a single intravenous dose 15 minutes before the ultrasound-guided TAP block.

Dexamethasone Group

Eligibility Criteria

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

You may qualify if:

• Women aged 18-40 years.
• Undergoing elective lower-segment cesarean section under spinal anesthesia.
• American Society of Anesthesiologists (ASA) physical status I or II.
• Singleton, full-term pregnancy with gestational age of at least 37 weeks.
• Willing to provide written informed consent.

You may not qualify if:

• Known allergy or contraindication to magnesium sulphate, dexamethasone, or local anesthetics.
• History of chronic pain disorders or regular use of analgesics or opioids.
• Neurological, renal, hepatic, or cardiovascular disease.
• Pregnancy complications such as pre-eclampsia, eclampsia, or placenta previa.
• Intraoperative conversion to general anesthesia.
• Inadequate spinal block or failed TAP block.
• Refusal to participate in the study.

Sponsors & Collaborators

• Khyber Teaching Hospital: lead

MeSH Terms

Conditions

Pain, Postoperative

Interventions

Magnesium Sulfate; Dexamethasone

Condition Hierarchy (Ancestors)

Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms

Intervention Hierarchy (Ancestors)

Magnesium Compounds; Inorganic Chemicals; Sulfates; Sulfuric Acids; Sulfur Acids; Sulfur Compounds; Pregnadienetriols; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Steroids, Fluorinated

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Participants, care providers, investigators, and outcomes assessors will be blinded to treatment allocation. Participants will be randomly assigned to receive either intravenous magnesium sulphate or intravenous dexamethasone. The study interventions will be prepared and administered according to the study protocol to maintain blinding. Postoperative outcome assessments and data collection will be performed by qualified anesthesiology residents blinded to group allocation.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Trainee medical officer

Model Details: Participants will be randomly assigned in a 1:1 ratio to two parallel intervention groups. Group M will receive a single intravenous dose of magnesium sulphate 50 mg/kg, while Group D will receive a single intravenous dose of dexamethasone 8 mg, with both interventions administered as adjuvants to bilateral ultrasound-guided TAP block following elective cesarean section. Participants will be followed for postoperative pain, rescue analgesic requirement, duration of analgesia, tramadol consumption, and adverse effects for 24 hours.

Study Record Dates

• First Submitted: August 14, 2026
• First Posted: August 19, 2026
• Study Start: September 1, 2026
• Primary Completion (Estimated): February 28, 2027
• Study Completion (Estimated): February 28, 2027
• Last Updated: August 19, 2026

Record last verified: 2026-08