A prospective comparative study of fentanyl and buprenorphine as an adjuvant to intrathecal chloroprocaine for perianal surgeries

Abstract

Introduction: Chloroprocaine is a local anesthetic with faster onset of action and short half-life, which results in short duration of analgesia limiting its use in surgeries. Researches proved that synergy with other drugs prolongs the duration of action and also the postoperative analgesia of chloroprocaine. Thus the present study was designed to compare the effectiveness of adding buprenorphine and fentanyl to intrathecal 1% 2-chloroprocaine for perianal surgeries. Materials and Methods: This prospective comparative study included 100 American Society of Anaesthesiologists physical class 1 and 2 patients of age 18–60 years, body mass index <35, scheduled for short duration perianal surgeries under spinal anesthesia. Patients were randomized into two groups: 30 mg 1% chloroprocaine was given along with 25 µg fentanyl in group F and 75 µg buprenorphine in group B. The time of onset, duration of sensory and motor block, two-segment and complete regression of spinal anesthesia, and duration of postoperative analgesia were studied. Results: Time for two-segment regression was 41.40 ± 7.82 and 44.80 ± 6.14 min in groups F and B, respectively, with P=0.43. In groups F and B, time to reach the modified Bromage score of 3 was 4.41 ± 0.48 and 4.17 ± 0.57 min, respectively. The time to void was insignificantly longer in group B than that in F of 300.96 ± 35.41 and155.86 ± 46.67 min without requirement of urinary catheterization. The time of first postoperative analgesic requirement was significantly longer in group B than that of group F of 715.82 ± 127.09 178.07 ± 453.13 min, respectively. Conclusion: The addition of intrathecal buprenorphine to chloroprocaine for spinal anesthesia significantly prolonged the postoperative analgesia compared with addition of fentanyl.