Rebound pain after interscalene brachial plexus block for shoulder surgery: a randomized clinical trial of the effect of different multimodal analgesia regimens

BACKGROUND: Rebound pain is characterized by sudden, significant acute postoperative pain occurring after the resolution of inter-scalene block (ISB); it affects the quality of recovery postoperatively. Dexamethasone increases ISB resolution time and decreases opioid consumption and the incidence of rebound pain. OBJECTIVE: Evaluate whether multimodal analgesia including intravenous dexamethasone administration with preoperative ISB reduces the incidence of rebound pain. DESIGN: Prospective, randomized, controlled trial SETTING: Tertiary university hospital SAMPLE SIZE: 60 patients PATIENTS AND METHODS: Patients who underwent shoulder surgery under general anesthesia were assigned randomly to two different multimodal analgesia protocols. Thirty patients received 5 mg IV dexamethasone with non-steroid, paracetamol, and ISB with 15 mL 0.5% bupivacaine, while the control patients received the same regimen and ISB with 15 mL 0.5% bupivacaine without dexamethasone. Postoperative opioids were given to any patient on demand. MAIN OUTCOMES MEASURES: Effect of IV dexamethasone on pain score and incidence of rebound pain after ISB resolution and postoperative opioid consumption at 0–48 hours, numerical pain rating scale (NPRS) scores, sleep scale scores, and quality of recovery-15 scores (QoR-15). RESULTS: The incidence of rebound pain was lower in the dexamethasone group than in the control group (73.3% and 30%, respectively, P =.001). NPRS scores after ISB resolution were lower in the dexamethasone group (5 ([4–7]), 8 ([5.75–8]), P <.001, respectively). Those who received IV dexamethasone had less sleep disturbances ( P <.001) and higher QoR-15 on day 1 ( P <.001) and day 7 ( P =.020) postoperatively. CONCLUSIONS: IV dexamethasone added to the ISB block resulted in a lower incidence of rebound pain. In addition, better results were obtained in postoperative sleep quality and QoR-15. LIMITATIONS: Single-center study