Although epidural anesthesia provides adequate anesthesia, it does not allay apprehension induced by fear of surgery and the alien environment of the operation theatre. Many adjuvants like opioids, ketamine, and α2 agonist have been studied as additives to local anesthetics in epidural anesthesia, each having its pharmacology profile and its side effects. The main aim of postoperative analgesia is to provide subjective comfort and inhibit nociceptive impulse caused by surgical trauma, and to blunt somatic and autonomic reflexes in response to pain. We compared the efficacy of plain ropivacaine vs. ropivacaine with magnesium sulfate on time of onset of sensory,motor block, and duration of analgesia.

Method: 60 patients undergoing elective lower limb surgeries were randomized into two groups. One group receives 16 ml of 0.75% ropivacaine; another group receives 16ml of 0.75%Ropivacaine with 1 ml of magnesium sulfate. Each patient was assessed the time of onset of sensory block, motor block, and duration of analgesia.

Results: Time of onset of sensory and motor block was statistically significant, whereas no significant difference is seen in the duration of analgesia.

Conclusion: Epidural magnesium 50 mg with 0.75% ropivacaine for lower limb surgeries shortens the onset of sensory and motor blockade with hemodynamic stability. There is no effect in prolonging the duration of analgesia. No significant adverse effects were seen.

Keywords: Epidural, ropivacaine, magnesium sulfate, sensory, and motor block.

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Rekha P.A.L.

Postgraduate, Department of Anaesthesiology, GEMS