Effect of Single Dose Intravenous Magnesium Sulfate on Postoperative Analgesic Consumption in Patients Undergoing Laparoscopic Cholecystectomy

December 27, 2025 updated by: Dr.Deb Sanjay Nag, Tata Main Hospital

This study describes a randomized controlled trial designed to evaluate the impact of a single intravenous dose of magnesium sulfate on postoperative analgesic consumption in patients undergoing laparoscopic cholecystectomy. The primary aim is to determine if magnesium sulfate can reduce postoperative morphine usage and its associated side effects.

The study will involve 106 patients (53 per arm), aged 18-65, classified as ASA physical status I or II, who are scheduled for elective laparoscopic cholecystectomy. Participants will be randomly assigned to receive either 30 mg/kg intravenous magnesium sulfate or a placebo (normal saline), alongside standard anesthetic care. Secondary outcomes include pain scores, the time until rescue analgesia is needed, and the monitoring of hemodynamic responses and potential adverse events. Statistical analysis will utilize descriptive statistics, chi-square tests, and t-tests or Mann-Whitney U-tests to compare the two groups.

Study Overview

Detailed Description

This study describes a meticulous randomized controlled trial designed to investigate the "Effect of single dose intravenous magnesium sulfate on postoperative analgesic consumption in patients undergoing laparoscopic cholecystectomy." The study addresses a critical clinical need, as laparoscopic cholecystectomy, despite being a minimally invasive procedure, often leads to significant postoperative pain. This pain traditionally necessitates opioid analgesics, which, while effective, come with a host of undesirable side effects such as nausea, vomiting, constipation, dizziness, and even respiratory depression. The study aims to explore multimodal analgesia (MMA) by specifically examining magnesium, a known NMDA receptor antagonist with analgesic properties, as a means to reduce opioid dependency and improve patient recovery.

The central research question revolves around whether a single intravenous dose of magnesium sulfate can effectively reduce postoperative analgesic consumption in this patient population. The null hypothesis posits that intravenous magnesium sulfate will decrease analgesic consumption, while the alternate hypothesis suggests no such effect.

The primary objective is to quantify the reduction in postoperative morphine consumption in the magnesium group compared to the placebo. Secondary objectives are comprehensive, including the evaluation of pain intensity using the Visual Analogue Scale (VAS), the time until patients require rescue analgesia, an assessment of hemodynamic stability, the impact on neuromuscular blockade, and the incidence of any other adverse events.

Methodologically, it will be a parallel, two-arm randomized controlled trial. Eligible participants will be adult patients (18-65 years) classified as ASA Physical status I or II, scheduled for elective laparoscopic cholecystectomy. Stringent exclusion criteria are in place to ensure patient safety and data integrity, covering factors like patient refusal, high BMI, obstructive sleep apnea, significant organ dysfunction, certain medication use, substance abuse, psychiatric illness, specific surgical durations, or conversion to open surgery.

Patients will be randomly assigned to one of two groups: the Magnesium Sulfate Group (M), receiving 30 mg/kg intravenous magnesium sulfate diluted in 100 ml Normal Saline at the induction of anesthesia, or the Normal Saline Group (S), receiving an equivalent volume of Normal Saline. Both groups will also receive standard multimodal analgesia with intravenous Diclofenac (75 mg) and Paracetamol (1 gm) at the time of port closure. Rescue analgesia, in the form of Morphine (3-4 mg), will be administered if a patient's VAS score is ≥ 4. Extensive intraoperative and postoperative monitoring will be conducted to track various physiological parameters and pain-related outcomes. A robust sample size of 117 patients (53 per arm, adjusted for a 10% attrition rate) has been determined to ensure sufficient statistical power (90%) to detect a 30% reduction in morphine use, with a two-sided significance level of 5%. Data analysis will be performed using SPSS, employing descriptive statistics, Chi-square tests for categorical variables, and independent samples t-tests or Mann Whitney U-tests for continuous variables, with a P-value < 0.05 considered statistically significant.

Study Type

Interventional

Enrollment (Estimated)

106

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • Jharkhand
      • Jamshedpur, Jharkhand, India, 831001
      • Jamshedpur, Jharkhand, India, 831011
        • Recruiting
        • Dr.Deb Sanjay Nag
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

Age - 18 - 65 years, either sex American Society of Anesthesiologists (ASA) Physical status classification system group I and II Elective laparoscopic cholecystectomy

Exclusion Criteria:

Patient refusal BMI > 30 kg/m² OSA Renal, hepatic or cardiovascular dysfunction including cardiac conduction disorders Those on long term calcium channel blockers or receiving magnesium supplements Opioid or analgesic abuse Psychiatric illness Surgical duration < 1 h & > 3 h Lap converted to open

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: MgSO4(Group: M)
The Magnesium Sulfate Group (M), receiving 30 mg/kg intravenous magnesium sulfate diluted in 100 ml Normal Saline at the induction of anesthesia,
Patients will be randomly assigned to one of two groups: the Magnesium Sulfate Group (M), receiving 30 mg/kg intravenous magnesium sulfate diluted in 100 ml Normal Saline at the induction of anesthesia, or the Normal Saline Group (S), receiving an equivalent volume of Normal Saline. Both groups will also receive standard multimodal analgesia with intravenous Diclofenac (75 mg) and Paracetamol (1 gm) at the time of port closure.
Placebo Comparator: Normal Saline (Group: S)
The Placebo Group Group (S) will recieve 100 ml Normal Saline at the induction of anesthesia.
Patients will be randomly assigned to one of two groups: the Magnesium Sulfate Group (M), receiving 30 mg/kg intravenous magnesium sulfate diluted in 100 ml Normal Saline at the induction of anesthesia, or the Normal Saline Group (S), receiving an equivalent volume of Normal Saline. Both groups will also receive standard multimodal analgesia with intravenous Diclofenac (75 mg) and Paracetamol (1 gm) at the time of port closure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Total dose of post-operative morphine consumption.
Time Frame: 24 hours
Rescue analgesia, in the form of Morphine (3-4 mg), will be administered if a patient's VAS score is ≥ 4.
24 hours

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Post operative Pain Scores Pain
Time Frame: 24 hours
Visual Analogue Scale
24 hours
Time to rescue analgesic
Time Frame: 24 hours
Time after the surgery when the patient asks for rescue analgesic or the patient's VAS score is ≥ 4.
24 hours

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

December 27, 2025

Primary Completion (Estimated)

October 31, 2026

Study Completion (Estimated)

December 31, 2026

Study Registration Dates

First Submitted

December 27, 2025

First Submitted That Met QC Criteria

December 27, 2025

First Posted (Actual)

January 9, 2026

Study Record Updates

Last Update Posted (Actual)

January 9, 2026

Last Update Submitted That Met QC Criteria

December 27, 2025

Last Verified

December 1, 2025

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Can be shared as per GDPR guidelines masking individual patient details.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Analgesia; Postoperative

Clinical Trials on Magnesium Sulfate 30 mg/kg intravenous diluted in 100 ml Normal Saline.

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