Anusha V. Sajjan, Shreedevi Yenni, Sanikop C. S
BACKGROUND In spinal anaesthesia, commonly used drugs are isobaric bupivacaine and hyperbaric bupivacaine. Commonly opioids like fentanyl are used as adjuvants with local anaesthetics to improve analgesic intensity and to achieve faster onset and prolonged duration. This study aims at comparing isobaric bupivacaine-fentanyl and hyperbaric bupivacaine-fentanyl primarily, in terms of onset and duration of sensory and motor blockade and secondarily, in terms of haemodynamic changes and associated complications. MATERIALS AND METHODS Eighty patients belonging to American Society of Anaesthesiologists I and II undergoing infraumbilical surgeries under spinal anaesthesia were randomised into two groups. Group A received 3 ml of 0.5% isobaric bupivacaine with 25 micrograms fentanyl, while Group B received 3 ml of 0.5% hyperbaric bupivacaine with 25 micrograms fentanyl. Student’s unpaired t-test and the χ2 test were used to analyse the results, using the SPSS version 11.5 software. RESULTS The mean onset of sensory block was significantly faster in Group B (3.55 ± 0.96 min) than in Group A (5.70 ± 0.69 min). The mean duration of sensory block was significantly longer in Group B (189.65 ± 9.58 min) than in Group A (129.08 ± 3.47 min). The mean onset of motor block was significantly faster in Group B (4.78 ± 0.80 min) than in Group A (7.83 ± 0.78 min). The mean duration of motor block was significantly longer in Group B (204.55 ± 12.46 min) than in Group A (171.18 ± 4.31 min). Isobaric bupivacaine-fentanyl mixture was associated with better haemodynamic stability as compared with hyperbaric bupivacaine-fentanyl mixture. CONCLUSION Intrathecal isobaric bupivacaine-fentanyl mixture is associated with lesser duration of both sensory and motor blockade, thereby enabling quicker recovery from anaesthesia and also better haemodynamic stability as compared with hyperbaric bupivacaine fentanyl mixture for infraumbilical surgeries.
