Dadichiluka Veeragouri Sankararao1, Kesava Vamsikrishna Bhairavabhatla2
BACKGROUND
Spinal anaesthesia requires a small volume of drug to produce profound sensory analgesia and motor blockade, but has limited duration of action. An adjuvant to local anaesthetic agent produces a better quality regional block. Intrathecal (IT) neostigmine has been used as an adjunct to Spinal Anaesthesia (SA) for the prevention of acute perioperative pain. It has been shown to potentiate opioid analgesia.1 According to recent literature, the inhibition of acetylcholine degradation by neostigmine enhances the descending control of afferent nociceptive stimuli and provides new approach for enhancement of desirable analgesia with few dose-related side effects.2 The use of neostigmine intrathecally does not cause any hypotension, sedation, respiratory depression or neurological dysfunction.2 Hence, we studied to compare the effect of intrathecal neostigmine 50 μg added to intrathecal hyperbaric bupivacaine with regard to sensory characteristics, motor characteristics and side effects.
MATERIALS AND METHODS
This was a prospective, randomised controlled double blinded study in 60 patients posted for infraumbilical surgeries belonging to ASA I and II status and aged between 18 to 60 years. One group received intrathecal 0.5% hyperbaric bupivacaine 3 mL (15 mg) group A and second group received preservative-free neostigmine 50 μg with 3 mL (15 mg) of intrathecal 0.5% hyperbaric bupivacaine group B and they were compared with regard to sensory characteristics, motor characteristics and side effects.
RESULTS
The addition of neostigmine 50 ug to hyperbaric bupivacaine prolonged mean duration of analgesia from the time of onset of complete sensory blockade to the time at which rescue analgesic was given using VAS score. It was 322.2 + 25.76 (SD) min. in the neostigmine group suggesting a statistically significant delay in onset of breakthrough pain between group A and group B.
CONCLUSION
Intrathecal neostigmine 50 ug with bupivacaine produces a good sensory and motor block for the surgical procedure with safe, durable and predictable postoperative analgesia. Administration of intrathecal neostigmine as an adjuvant to bupivacaine produces effective, prolonged and haemodynamically stable postoperative analgesia as compared to administration of intrathecal bupivacaine alone.2
