Intrathecal Morphine Versus Intrathecal Dexmedetomidine Compared to Placebo for Postoperative Pain Relief After Spine Fixation Surgeries

Intrathecal Morphine Versus Intrathecal Dexmedetomidine Compared to Placebo for Postoperative Pain Relief After Spine Fixation Surgeries: A Randomized Double-Blinded Study

This study aims to compare the efficacy of intrathecal morphine and intrathecal dexmedetomidine in reducing pain following lumbar spine fixation surgeries.

Spine surgeries represent a challenge to the anesthetists, as they are accompanied by multiple perioperative problems, including significant intraoperative blood loss and severe postoperative pain.

Morphine is a prototypical opioid analgesic that acts mainly on mu-opioid receptors in the central nervous system. It exerts its analgesic effects by binding to these receptors, inhibiting the release of a neurotransmitter known as substance P, thereby diminishing pain perception.

Dexmedetomidine (DEX) is a highly selective and potent α-2 adrenoceptor agonist. Its intrathecal administration leads to anti-nociceptive effects, although it has some undesired side effects (e.g., hypotension, bradycardia, and sedation).

Inclusion Criteria:

• Aged between 21 and 60 years.
• Both sexes.
• American Society of Anesthesiologists (ASA) Physical Status I or II.
• Scheduled for elective lumbar spine fixation surgery under general anesthesia.

Exclusion Criteria:

• Patients' refusal.
• Decompensated hepatic or renal or cardiac disease.
• Coagulation disorder.
• Pregnancy and lactation.
• Body mass index above 30 kg/m2.
• Severe pulmonary disorders.
• Patients on opioid, alcohol or allergy to any of the study drugs.