The Effect of Preoperative Interscalene Block Using Low-Dose Mepivacaine on the Postoperative Pain after Shoulder Arthroscopic Surgery

Cho, Yong Hyun; Shin, Seung Ho; Lee, Dong Hyun; Yu, Eun Young; Yoon, Myo Seop

Abstract

BACKGROUND: Shoulder arthroscopic surgery is frequently associated with severe postoperative pain, which can be difficult to manage without the use of high-dose opioids. Although an interscalene brachial plexus block (ISBPB) can be used to provide anesthesia for shoulder arthroscopic surgery, its effect using low-dose mepivacaine on postoperative pain management has not been reported. We hypothesized that ISBPB using a low-dose mepivacaine can provide effective postoperative analgesia for shoulder arthroscopic surgery without the need for high-dose opioids and act as a significant motor or sensory block.
METHODS
This study examined a total of 40 patients, who underwent shoulder arthroscopic surgery, and received ISBPB with 10 ml of normal saline (group NS; n = 20) or 10 ml of 1% mepivacaine with epinephrine 1:200,000 (group MC; n = 20). The block was performed preoperatively. The postoperative pain score, opioid consumption, and side effect were recorded.
RESULTS
The visual analog scale scores were significantly lower in group MC than in group NS at 120 minutes after shoulder arthroscopic surgery (1.9 +/- 1.0 versus 4.0 +/- 1.4). Group MC showed significantly lower fentanyl consumption after shoulder arthroscoic surgery than group NS (27 +/- 32.6 versus 79 +/- 18.9microgram). The degree of motor and sensory block after surgery was minimal.
CONCLUSIONS
ISBPB using low-dose mepivacaine reduced the level of postoperative pain and fentanyl consumption without significant side effects. ISBPB using low-dose mepivacaine is a useful analgesic technique for shoulder arthroscopic surgery.