Intrathecal Midazolam for Postoperative Analgesia in Adults

ABSTRACT

Introduction: Midazolam produces an analgesic actionthrough the benzodiazepine/γ-aminobutyric acid (GABA)Areceptor complex in the spinal cord. We conducted this studyto evaluate postoperative analgesic effects and associatedcomplications of intrathecal midazolam in patients undergoingperineal surgery.Material and methods: 30 subjects belonging to ASA gradeI and II scheduled to undergo elective perineal surgery underspinal anaesthesia were randomly allocated to either GroupA- 1 ml of 0.5% heavy bupivacaine+saline or Group B- - 1ml of 0.5% heavy bupivacaine+preservative free midazolam.The duration of postoperative analgesia, postoperative visualanalogue scores for pain, and perioperative side effects werenoted.Results: The basic demographic characteristics were similarbetween the two groups. The mean duration of surgery was22.33 ± 14.96 in group A, and it was 16.8 ± 12.55 in group B.The mean time to first pain medication was 4.93 ± 3.32 hoursin group A, and it was 8.63 ± 6.17 in group B. The mean VASat first pain medication was 40.00 ± 00 mm, and it was 40.00± 00 mm in group B. the mean difference in the postoperativeanalgesia between group was statistically significant (P value<0.02). Hemodynamic parameters did not differ between thegroups. The complications included urinary retention among 5(33.33%) in group A and 6 (40.00%) in group B.Conclusion: The addition of preservative-free midazolam tobupivacaine intrathecally resulted in prolonged postoperativeanalgesia without any significant side effects