Comparison of two different doses of intrathecal Neostigmine as an adjuvant to Bupivacaine for postoperative analgesia

Abstract

Subarachnoid block (SAB) using Bupivacaine lacks postoperative analgesia. Aim of present study was to assess safety and efficacy of 50 µ and 100µ intrathecal Neostigmine for postoperative analgesia. Ninety patientsof age 18 to 65 were allocated randomly to three groups of 30 each and studied prospectively by double blind controlled trial. Patient posted for lower limb and lower abdominal surgeries were given SAB using 3 ml Bupivacaine 0.5% in group A, 2.9 ml Bupivacaine + 50 µ Neostigmine in B and 2.8 ml Bupivacaine and 100µ Neostigmine in C.Patients were monitored for onset, regression of sensory and motor block, blood pressure and heart rate. Postoperatively patients were assessed for pain score using visual analogue scale (VAS) and duration of analgesia by rescue analgesia requirement. 90 patients enrolled were analysed. VAS pain score was more in group A compared to B which had higher than group C. Analgesia was prolonged in group C than in B which had better analgesia than group A. Incidence of nausea, vomiting and bradycardia was higher with 100µ Neostigmine than 50 µ.Intrathecal Neostigmine 50 µ dose as an adjuvant to Bupivacaine is associated with good postoperative analgesia and hemodynamic stability while 100 µ dose was associated with more prolonged analgesia and higher incidence of adverse effects.