Comparative Arthroscopic Rotator Cuff Repair Outcomes Associated with Continuous Interscalene Block vs. Bolus Interscalene Block with Intravenous Dexmedetomidine: A Retrospective Cohort Study

<b>Background/Objectives:</b> This retrospective cohort study compared the outcomes (postoperative pain, morphine consumption, sleep disturbance, and function) of patients undergoing arthroscopic rotator cuff repair involving either continuous interscalene block (CISB group) or single-injection interscalene block with intravenous dexmedetomidine (SISB group) analgesia. <b>Methods</b>: This study included 61 patients, aged 59-71 years, who underwent elective arthroscopic rotator cuff repair and for whom complete electronic health records were available. Patients in the SISB group received a single-injection nerve block plus intraoperative intravenous dexmedetomidine and postoperative patient-controlled analgesia (PCA; morphine and dexmedetomidine; <i>n</i> = 33). Patients in the CISB group received continuous nerve block and morphine PCA (<i>n</i> = 28). Patient sleep disturbances, pain, total morphine consumption, and functional outcomes were evaluated postoperatively. <b>Results</b>: During the first 36 h postoperatively, there were no significant differences in the measured effects for patients in the two groups. Similarly, there were no significant differences in functional outcomes. However, patients in the SISB group had a significantly lower median morphine consumption total (18 mg) than those in the CISB group (24 mg; <i>p</i> < 0.001). <b>Conclusions</b>: Patients in the SISB group demonstrated significantly lower median morphine consumption than those in the CISB group; however, the postoperative pain, frequency of sleep disturbances, nausea, and functional outcomes did not show statistically significant differences. The reduced morphine consumption associated with the SISB group, compared with the CISB group, suggests that this analgesic protocol may result in fewer opioid-related effects following arthroscopic rotator cuff repair.