Effect of interscalene brachial plexus block with dexmedetomidine and ropivacaine on postoperative analgesia in patients undergoing arthroscopic shoulder surgery: a randomized controlled clinical trial.

Background: Dexmedetomidine, a potent and highly selective α2-adrenoreceptor agonist has become a popular adjuvant to local anesthetics. The study was designed to explore the effect of dexmedetomidine added to ropivacaine for interscalene brachial plexus block (IBPB) on postoperative analgesia in patients undergoing arthroscopic shoulder surgery.

Methods: Forty-four adult patients undergoing arthroscopic shoulder surgery were randomly divided into 2 groups. Group R received 0.25% ropivacaine alone, whereas group RD received 0.25% ropivacaine and 0.5 μg/kg dexmedetomidine. A total volume of 15 ml was administered for ultrasound-guided IBPB in both groups. Duration of analgesia, visual analog scale (VAS) pain score, frequency of PCA pressed, first time of PCA pressed, sufentanil consumption, and patient satisfaction with analgesia quality were recorded.

Results: Compared with group R, the duration of analgesia was prolonged (8.25±1.76 vs. 11.55±2.41 h; P<0.05), the VAS pain scores were decreased at 8 and 10 h postoperatively (3 (2-3) vs. 0 (0-0) and 2 (2-3) vs. 0 (0-2.25), respectively; P<0.05), the frequencies of PCA pressed were decreased at 4-8 and 8-12 h time intervals (0 (0-0.25) vs. 0 (0-0) and 5 (1.75-6) vs. 0 (0-2), respectively; P<0.05), the time of first PCA pressed was prolonged (9.27±1.85 vs. 12.98±2.35 h; P<0.05), the total 24h sufentanil consumption was reduced (108.72±15.92 vs. 94.65±12.47 μg; P<0.05 ) and patient satisfaction score was also improved (3 (3-4) vs. 4 (4-5); P<0.05) in group RD.

Conclusion: We concluded that adding 0.5 μg/kg dexmedetomidine to 0.25% ropivacaine for IBPB provided better postoperative analgesia, decreased the sufentanil consumption and improved the patient's satisfaction in patients undergoing arthroscopic shoulder surgery.