EFFECT OF INTRATHECAL NALBUPHINE AND MAGNESIUM SULPHATE USED AS ADJUVANTS WITH BUPIVACAINE IN SPINAL ANAESTHESIA FOR LOWER ABDOMINAL SURGERY: A COMPARISON

BACKGROUND Nalbuphine, a semi-synthetic, mixed agonist-antagonist opioid, has a potential to attenuate the mu-opioid effects and to enhance the kappa-opioid effects. The use of different adjuvants including Nalbuphine with local anaesthetics extends the duration of surgical anaesthesia including postoperative analgesia. METHODS Randomised, double blinded, case control study conducted in 100 adult ASA I and II patients divided randomly into two groups of 50 each undergoing lower abdominal surgeries Group M received (100 mg/0.2 mL) 50% preservative free Magnesium Sulfate and Group N received (0.8 mg/0.2 mL) 0.4% Nalbuphine along with 3 mL of 0.5% heavy bupivacaine each intrathecally. RESULT The onset of T10 sensory block 5.75 +/- 0.74 min. in group M and 4.20 +/- 0.67 min. in group N, which is significantly faster in group N (p<0.0001). Time of regression to S1 sensory level is 199.44 +/- 10.41 min. in group M and 154.84 +/- 8.11 min. in group N, which is prolonged in group M (p<0.0001). The mean time for rescue analgesia in group M is 241.06 +/- 19.61 minutes and group N is 257.30 +/- 28.50 min., which is statistically significant (P value=0.0013), i.e. prolonged postoperative analgesia in group N. CONCLUSION Nalbuphine has faster onset of anaesthesia and provides prolonged postoperative analgesia compared to magnesium sulphate when used as adjuvants with bupivacaine in spinal anaesthesia.