Background: Spinal anaesthesia is widely used for lower abdominal surgeries due to its rapid onset and effective neural blockade. Hyperbaric bupivacaine is the conventional agent, but concerns regarding prolonged motor block and cardiotoxicity have led to the exploration of alternatives such as hyperbaric ropivacaine, which offers a better safety profile and faster recovery. Aim: To compare the efficacy and safety of hyperbaric bupivacaine 0.5% and hyperbaric ropivacaine 0.75% in spinal anaesthesia for lower abdominal surgeries. Materials and Methods: This prospective randomized study included 60 patients (ASA I–II) undergoing elective lower abdominal surgeries. Patients were divided into two groups: Group B received 0.5% hyperbaric bupivacaine (3 mL), and Group R received 0.75% hyperbaric ropivacaine (3 mL). Parameters assessed included onset and duration of sensory and motor block, time to two-segment regression, hemodynamic changes, and adverse effects. Results: The onset of sensory and motor block was significantly faster in Group B (p < 0.01). Group B also demonstrated a longer duration of both sensory and motor blockade. However, Group R showed significantly shorter motor block duration and faster regression (p < 0.001). Hemodynamic stability was better in Group R, with a lower incidence of hypotension and bradycardia. Conclusion: While bupivacaine provides faster onset and prolonged anaesthesia, ropivacaine offers better hemodynamic stability and quicker recovery, making it more suitable for ambulatory and short-duration procedures.

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