Effects of single-injection vs. continuous brachial plexus blocks for shoulder surgeries on patient-reported outcomes: a systematic review and meta-analysis with trial sequential analysis of randomised controlled trials.
INTRODUCTION: Single-injection and continuous brachial plexus block techniques are used widely for postoperative analgesia in patients undergoing shoulder surgery. Although patient-reported outcomes are described in individual studies, their effects have not been synthesised comprehensively using a patient-centred framework. We sought to compare the effects of single-injection vs. continuous brachial plexus block techniques on patient-reported outcomes in adult patients following elective shoulder surgery. METHODS: Databases were searched from inception to October 2025 and randomised controlled trials reporting patient-reported outcomes were included. Co-primary outcomes were postoperative patient-reported pain intensity at rest and during movement at 12 h, 24 h and 48 h post-surgery. Secondary outcomes included nausea and vomiting; sleep quality; patient satisfaction; opioid requests; and functional scores. Random-effects meta-analysis and trial sequential analysis were performed, with risk of bias and quality of patient-reported outcome reporting assessed. RESULTS: Twenty randomised controlled trials that included 1198 patients were analysed. Continuous brachial plexus blocks were associated with lower pain at rest at 12 h, 24 h and 48 h, with mean differences (MD) of -1.96 (95%CI -2.81 to -1.11, p < 0.001), -1.66 (95%CI -2.27 to -1.05, p < 0.001) and - 1.18 (95%CI -1.84 to -0.53, p < 0.001), respectively. Pain on movement could only be pooled at 24 h and 48 h and showed MD -2.04 (95%CI -4.26-0.19, p = 0.07) and - 1.30 (95%CI -3.67-1.07, p = 0.28) respectively. The co-primary outcomes approached or exceeded the predefined minimal clinically important difference for pain scores after shoulder surgery, in favour of continuous techniques. DISCUSSION: Continuous brachial plexus blocks are associated with better pain at rest and other patient-centred outcomes following shoulder surgery, while effects on dynamic pain and long-term functional recovery remain uncertain.