Background: Various intrathecal additives are added to local anesthetics to increase the speed of onset, improve the quality, and prolong the
inuence of spinal anesthesia. Midazolam has a synergistic effect on postoperative analgesia when administered intrathecally with bupivacaine.
Opioids such as fentanyl are extensively used as an adjunct to local anesthetics in neuraxial blockade to enhance the duration of postoperative
analgesia. Aim: The aim of our study was to compare the effects of intrathecal midazolam(1mg) and fentanyl (25 micrograms) as additives to
intrathecal hyperbaric bupivacaine 0.5% (15mg) with spinal anesthesia.Materials and Methods: Prospective, observational study was conducted
at SRI SIDDHARTHAMEDICAL COLLEGE AND RESEARCH INSTITUTE,TUMKUR. from 1st Jan 2021 to 30th June 2022 on 94 patients.
Results: In Bupivacaine and Midazolam group, mean duration of surgery was 84 ± 12.3 minutes and in Bupivacaine and Fentanyl group, mean
duration of surgery was 92 ± 14.4 minutes. In Bupivacaine and Midazolam group, mean time for onset of sensory block was 7.1 ± 0.9 minutes and in
Bupivacaine and Fentanyl group, mean time for onset of sensory block was 6.9 ± 1.1 minutes. In Bupivacaine and Midazolam group, mean time for
onset of motor block was 7.6 ± 1.3 minutes and in Bupivacaine and Fentanyl group, mean time for onset of motor block was 8.1± 1.2 minutes. In
Bupivacaine and Midazolam group, mean duration of sensory block was 213.6 ± 16.1 minutes and in Bupivacaine and Fentanyl group, mean
duration of sensory block was 218.3 ± 19.2 minutes. Conclusion- The onset of sensory and motor blockade was comparable in Fentanyl with
Bupivacaine and Midazolam with Bupivacaine. Additional of intrathecal Fentanyl prolonged the duration of analgesia signicantly than that of
Midazolam. There was signicantly less consumption of rescue of analgesia among patients with Fentanyl with Bupivacaine than Midazolam with
Bupivacaine. The duration of postoperative analgesia was also signicantly prolonged in the fentanyl and midazolam groups
