Comparative Evaluation of Intrathecal Magnesium Sulphate vs. Clonidine as Adjuvants to Hyperbaric Bupivacaine in Spinal Anaesthesia

Abstract

Background: Spinal anaesthesia is the favored approach for lower abdomen and lower limb procedures because it is simple and effective. However, due to the short duration of analgesia provided by local anaesthetics alone, adjuvants are frequently used in conjunction.

Objective: The major goal of this study was to assess and compare the onset and duration of sensory and motor block, hemodynamic stability, and duration of postoperative analgesia between Magnesium Sulphate and Clonidine when used as intrathecal adjuvant.

Methods: The Department of Anaesthesia at Patna Medical College and Hospital (PMCH) carried out a prospective, cross-sectional comparative study between February and September. 99 adult patients with ASA physical status I or II, ages 18 to 60, who were scheduled for elective lower abdominal or lower limb procedures made up the study population. To assess various anesthetic regimens, these individuals were divided into three equal groups of thirty-three at random. While the intervention groups got adjuvants, Group B received 0.5% hyperbaric Bupivacaine mixed with normal saline; Group M received Bupivacaine with 50 mg of magnesium sulphate; and Group C received Bupivacaine plus 30 µg of Clonidine.

Results: According to the study, Group C experienced sensory and motor block far more quickly than both Group M and Group B (p < 0.05). Group C had the longest duration of postoperative analgesia (330.7 ± 47.7 min), followed by Group M (246.3 ± 55.9 min), and Group B had the smallest length (134.4 ± 17.9 min). Group M showed a more favorable profile in terms of hemodynamic stability, while Group C was associated with a higher incidence of bradycardia and hypotension despite its stronger analgesic efficacy.

Conclusion: Magnesium Sulfate and Clonidine are both excellent adjuvants for intrathecal bupivacaine. Clonidine has a longer duration of analgesia and a speedier onset, although it requires close hemodynamic monitoring. Magnesium Sulphate is a valuable option that provides extended analgesia while also having a higher safety profile in terms of hemodynamic stability.