D-FAB-POUR Trial: Dexmedetomidine vs Fentanyl as Adjuvants to Bupivacaine on Postoperative Urinary Retention

"Intervention 1: Intrathecal Dexmedetomidine with Bupivacaine~Detailed Description:~This intervention consists of a single intrathecal injection of 10 micrograms of dexmedetomidine combined with 15 mg (3 mL) of 0.5% hyperbaric bupivacaine, administered during spinal anaesthesia for lower limb surgery. The total volume administered is 3.5 mL. Dexmedetomidine is an alpha-2 non-opioid adjuvant used as a spinal adjuvant for enhancing analgesia"

This intervention consists of a single intrathecal injection of 25 micrograms of fentanyl combined with 15 mg (3 mL) of 0.5% hyperbaric bupivacaine, administered during spinal anesthesia for lower limb surgery. The total volume administered is 3.5 mL. Fentanyl is a lipophilic opioid commonly used as a spinal adjuvant for enhancing analgesia. This arm is being compared with dexmedetomidine to evaluate differences in POUR incidence, analgesic effectiveness, and side effect profiles.