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.

Abstract

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. 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. 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. 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.