DOI: https://doi.org/10.36347/sjams.2026.v14i02.029

Pages: 315-321

Background: Spinal anesthesia is widely regarded as the preferred method for lower abdominal surgeries due to its cost-effectiveness, safety, and ability to provide postoperative analgesia while preserving mental clarity and airway reflexes. This study aimed to compare the block characteristics and hemodynamic effects of intrathecal dexmedetomidine versus fentanyl when added to hyperbaric bupivacaine in patients undergoing saddle block for perianal surgeries. Methods: This quasi-experimental study at the Departments of Anaesthesia, Analgesia and Intensive Care Medicine, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh (Oct 2021–Sep 2022), enrolled 64 perianal surgery patients assigned to bupivacaine–fentanyl or bupivacaine–dexmedetomidine groups, assessing block, hemodynamics, analgesia duration, and complications. Data were analyzed with SPSS 23.0 (t-test/Chi-square, p < 0.05). Results: Sixty-four patients received saddle block with bupivacaine 7.5 mg plus fentanyl 15 μg (Group A) or dexmedetomidine 5 μg (Group B). Baseline characteristics were comparable. Sensory (4.82 vs 4.65 min) and motor block onset (12.26 vs 11.58 min) were similar. Hemodynamics remained stable, with minor mid-interval decreases. Group B had longer sensory (292.1 min) and motor block (162.5 min) and prolonged analgesia (278.5 vs 198.7 min, p = 0.0001). Hypotension occurred in 2 patients in Group A; no cardiovascular collapse was noted. Conclusion: Intrathecal dexmedetomidine prolongs sensory and motor block and analgesia more than fentanyl while maintaining stable hemodynamics and minimal complications in saddle block.