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

Phase 2
Not yet recruiting
Conditions
Abdominal Hysterectomy
Interventions
Registration Number
NCT06367595
Lead Sponsor
Assiut University
Brief Summary

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.

Detailed 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.

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
Female
Target Recruitment
90
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

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
intravenousMagnesium sulfatewill 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.
intrathecalMagnesium sulfatewill 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.
placeboMagnesium sulfatewill 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.
Primary Outcome Measures
NameTimeMethod
effect on postoperative pain after abdominal hysterectomy using visual analog scoreBaseline

the pain intensity assessment at rest and on movement (from lying to sitting on the bed) using Visual analog score (VAS) This will measure pain intensity from 0 to 10 (goal is to be \< 4) 0: no pain 3: mild pain 7: moderate pain 10: severe pain

Secondary Outcome Measures
NameTimeMethod
Heart rate (HR)Baseline

Heart rate (HR) will be recorded at time 0 then every 15 minutes in the first 2 hours, then at 6, 12, 24 hours postoperatively.

sedation by Ramsay sedation scaleBaseline

From 1 to 6

1. Patient is anxious and agitated or restless, or both.

2. Patient is cooperative, oriented, and tranquil.

3. Patient responds to commands only.

4. Patient exhibits brisk response to light glabellar tab or loud auditory stimulus.

5. Patient exhibits a sluggish response to light glabellar tap or loud auditory stimulus.

6. Patient exhibits no response.

time of the first opioid requestBaseline

time of the first opioid request, concentration and the occurrence of complications (hypotension, bradycardia, itching, urinary retention.) all over 24 hours postoperatively.

Mean arterial blood pressures (MAP)Baseline

mean arterial blood pressures (MAP) will be recorded at time 0 then every 15 minutes in the first 2 hours, then at 6, 12, 24 hours postoperatively.

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