Background: Spinal anaesthesia is the primary anaesthetic technique for many types of surgery. Limiting the dose of local anaesthetic used in spinal anaesthesia has been an aggressive topic of study as it will achieve rapid anaesthetic recovery as well as reduce the incidence and severity of its side effects.

Context: In our study we compared clonidine and magnesium as adjuvants to hyperbaric bupivacaine in spinal anaesthesia in terms of duration of sensory and motor block, sedation, respiratory depression and haemodynamic parameters.

Aim: To compare Clonidine and Magnesium sulphate as adjuvants to bupivacaine heavy 0.5% for spinal anaesthesia in patients undergoing infraumbilical surgeries in terms of analgesic efficacy, duration of sensory block and adverse effects.

Settings and Design: Conducted in ASA I-II patients with age group 18-60 years undergoing infraumbilical surgical procedures. Patients were randomly divided into three groups each of 25 patients. Group 1 (B) received 14 mg (2.8ml of 0.5%) preservative free hyperbaric bupivacaine 0.2 ml NS; Group 2 (BC) received 14 mg (2.8ml of 0.5%) preservative free hyperbaric bupivacaine+0.2 ml clonidine (30µg); Group 3 (BM) received 14 mg (2.8ml of 0.5%) preservative free hyperbaric bupivacaine+0.2 ml MgSO4 (100mg.

Statistical analysis used: The data of the study were recorded in the record chart and results were evaluated using statistical tests (ANOVA, student t-test, chi-square test and post hoc test, F-test whichever was applicable).

Results: The onset of sensory block and motor block was significantly delayed in group BM as compared to group B and BC. The duration of motor block was significantly prolonged in the Group BM and BC as compared to Group B.

Conclusions: Magnesium is superior to Clonidine as an adjuvant to bupivacaine for infraumbilical and lower limb surgeries.