Postoperative Analgesia Effect Evaluation of Perineural Dexamethasone Plus Various Doses of Ropivacaine in Interscalene Brachial Plexus Block

Objectives: Interscalene brachial plexus block (ISBPB) has gained popularity as a pain-relief method following shoulder arthroscopic surgery, significantly reducing the need for analgesics. This study was designed to evaluate whether the addition of dexamethasone to different effective concentrations of ropivacaine in ultrasound-guided ISBPB affects postoperative analgesic effect in patients undergoing shoulder arthroscopy surgery. Materials and Methods: A total of 140 subjects elected for shoulder arthroscopy under ISBPB and general anesthesia, randomized into six equal groups. Group A, B, and C received 10 mL 0.25%, 0.5%, and 0.75% ropivacaine mixed with 1 mL 0.9% saline, respectively. Likewise, Groups A1, B1, and C1 received the same volumes of ropivacaine with 5 mg dexamethasone. The primary goal was to assess the duration of analgesia with ISBPB, with secondary objectives concerning postoperative nausea and vomiting (PONV) and numerical rating scale (NRS) pain scores. Results: Across a range of ropivacaine concentrations, there was no significant difference in the analgesic efficacy between subjects receiving dexamethasone treatment and those who did not. Notably, there was no demonstrable difference in the duration of analgesia among the treatment groups (Group A vs. Group A1: 510.13±262.39 min, 518.21±395.49 min; P =0.054); (Group B vs. Group B1: 672.42±306.63 min, 646.05±348.48 min; P =0.281); (Group C vs. Group C1: 724.42±384.14 min, 680.29±414.30 min; P =0.782). Furthermore, there was no significant difference in the incidence of intraoperative and postoperative complications. Conclusion: The present study indicated that the addition of dexamethasone to ropivacaine did not appear to provide any additional advantages in postoperative analgesic efficacy compared to the use of ropivacaine alone for patients undergoing shoulder arthroscopy surgery with ISBPB.