Comparison of Magnesium Sulphate 100mg and Fentanyl 25µg as Adjuvants to Intrathecal Hyperbaric Bupivacaine 0.5% for Infraumbilical Surgeries

Introduction: Intrathecal adjuvants have gained popularity for prolonging the duration and quality of block; opioids (fentanyl and sufentanil) and other drugs like magnesium sulphate, midazolam, clonidine and ketamine are used. Methods: We conducted double blinded, prospective study on total of 90 patients, who were randomly allocated into three groups. Inclusion Criteria: 1. ASA grade I&II. 2. Patients of either gender between ages of 18-60 years. Exclusion Criteria: 1. Patients with severe systemic disease - hepatorenal, cardiovascular diseases and bleeding disorders. 2. Patients with allergy to opioid. Discussion: In our study, it was observed that Bromage score 3 was achieved earliest in group C in 10 min while in other groups it was delayed. Ozalevli et al. observed a similar delay when adding intrathecal magnesium to fentanyl and isobaric bupivacaine (we used hyperbaric bupivacaine in our study Conclusion: Addition of magnesium sulphate at 100 mg dose or fentanyl 25 μg as adjuvants to intrathecal bupivacaine significantly prolongs the duration of analgesia. At these doses, magnesium provides better haemodynamic stability than fentanyl, with fewer side effects. References: Ozalevli M, Cetin TO, Unlugenc H, Guler T, Isik G. The effect of adding intrathecal magnesium sulphate to bupivacaine-fentanyl spinal anaesthesia. Acta Anaesthesiol Scand 2005; 49: 1514-9.