Effect of Intrathecal Magnesium Sulfate Versus Intravenous Magnesium Sulfate on Postoperative Pain After Abdominal Hysterectomy

Assiut University

Status and phase: Not yet enrolling; Phase 2

Conditions: Abdominal Hysterectomy

Treatments: Drug: Magnesium sulfate

Study type: Interventional

Funder types: Other

Identifiers

NCT06367595

Intrathecal MgSO4

Details and patient eligibility

About

The present study aims to compare the effect of adding IV magnesium sulfate versus magnesium sulfate to intrathecal hyperbaric bupivacaine in total abdominal hysterectomy regarding the duration of postoperative analgesia, hemodynamic stability, and complications.

Full description

Abdominal Hysterectomy (AH) is associated with an intense inflammatory response that can result in moderate to severe postoperative pain, sometimes difficult to control.

Postoperative pain can cause many complications such as restlessness, increased sympathetic activity, high blood pressure, and tachycardia. Opioids are effective analgesics; however, they produce unwanted side effects, such as respiratory depression, nausea, and vomiting. Nonopioid drugs can decrease opioid usage and dependency.

Different adjuvants have been added to local anesthetics to increase the duration of the regional anesthesia, decrease pain-relieving drugs, and delay the onset of postoperative pain.

According to numerous reports, Magnesium sulfate has analgesic effects and lowers opioid consumption in many surgeries especially abdominal surgeries.

The analgesic properties of magnesium are based on acting as a non-competitive antagonist of N-Methyl-D-Aspartate (NMDA) receptors in central nervous system and regulating the calcium influx into the cell. These properties avoid the central sensitization mechanisms due to the stimulation of peripheral nociceptive nerves In the spinal cord, magnesium sulfate decreases pain transmission by hyperpolarizing spinal interneurons via G-protein-mediated activation of potassium channels and by decreasing the release of the neurotransmitters (substance P and glutamate) from primary afferent terminals.

Adequate postoperative pain relief can enhance recovery and increase patient satisfaction.

Enrollment: 90 estimated patients

Sex: Female

Ages: 40 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients between 40-65 years old
• Patients with ASA clinical status I/II
• Patients eligible for abdominal hysterectomy
• Oncological surgery

Exclusion criteria

• Body mass index (BMI) ≥ 40/kg / m2
• Previous abdominal surgery (except cesarean section)
• Severe cardiovascular, renal, and hepatic dysfunction
• Contraindications to spinal anesthesia
• Neuromuscular diseases
• Inappropriate for spinal anesthesia
• Patient refusal

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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90 participants in 3 patient groups, including a placebo group

intrathecal

Active Comparator group

Description:

will include 30 patients who will receive * Intrathecal hyperbaric bupivacaine 0.5 % 20 mg in 4 ml plus magnesium sulfate 30 mg of 0.5 ml volume. * 250 ml of isotonic saline infusion over 15 minutes immediately before spinal anesthesia, then 250 ml of isotonic saline infusion over 2 hours.

Treatment:

Drug: Magnesium sulfate

intravenous

Active Comparator group

Description:

will include 30 patients who will receive - 30 mg/kg magnesium sulfate at a concentration of 100 mg/ml (regarding the ideal body weight) in 250 ml of isotonic saline infusion over 15 minutes immediately before spinal anesthesia (intrathecal hyperbaric bupivacaine 0.5 % 20 mg in 4 ml plus 0.5 ml of isotonic saline), and then 10 mg/kg/h magnesium sulfate in 250 ml isotonic saline infusion over 2 hours.

Treatment:

Drug: Magnesium sulfate

placebo

Placebo Comparator group

Description:

will include 30 patients who will receive * intrathecal hyperbaric bupivacaine 0.5 % 20 mg in 4 ml plus 0.5 ml of isotonic saline. * 250 ml of isotonic saline infusion over 15 minutes immediately before spinal anesthesia then 250 ml of isotonic saline infusion over 2 hours.

Treatment:

Drug: Magnesium sulfate