Comparison between Neostigmine Methylsulphate and Clonidine Hydrochloride with Heavy Bupivacaine in Spinal Anesthesia for Elective Abdominal Hysterectomy

Introduction: Intrathecal neostigmine acts by inhibition of breakdown of acetylcholine. It produces analgesia by increased concentration of acetylcholine in spinal cord. Intrathecal clonidine acts on post synaptic alpha 2 agonist and produces analgesia by inhibition of WDR (wide dynamic range) neurons. In this study we compared effects clonidine and neostigmine intrathecally for elective abdominal hysterectomy. Materials and Methods: Total 60 patients posted for elective abdominal hysterectomy divided in two groups. Group N (n=30) received 3 ml of 0.5% heavy bupivacaine with 45 mcg of neostigmine .Group C (n=30) received 3 ml of 0.5% heavy bupivacaine with 45 mcg clonidine. Both groups were compared for onset and duration of sensory and motor blockage, haemodynamic stability and post-operative analgesia. Results: Time for sensory onset (T10) was faster in group N (1.65 ± 0.66 min) than group C (3.71± 1.99 min). Time for onset of motor block was faster in group N (1.74± 0.49 min) than group C (4.12 ± 2.46 min). Post-operative analgesia was prolonged in group C (326 ± 11.76 min) than in group N (280 ± 14.61min). Hypotension, bradycardia and sedation were more seen in group C while nausea and vomiting were more seen in group N. Conclusion: Intrathecal neostigmine with bupivacaine in elective abdominal hysterectomy provides faster sensory and motor blockade while prolonged post-operative analgesia seen with intrathecal clonidine .Both drugs can safely used as an adjuvant as an alternative to opioid free spinal analgesia.