Adverse event reporting in ultrasound-guided brachial plexus blocks: A scoping review

Ultrasound-guidance during peripheral nerve blocks has become increasingly popular over the past two decades, with recommendations for formal residency training defined in 2009. With increasing numbers of upper extremities surgeries, ultrasound-guided brachial plexus blocks (BPBs) are commonly utilized in both healthy and complex patients, but are associated with specific adverse events. However, the reporting of adverse events in ultrasound-guided BPBs remains inconsistent. This scoping review examines recent publications on ultrasound-guided BPBs, with a focus on adverse event reporting and the terminology used to describe these outcomes. Based on a comprehensive literature search between 2014 and 2024, 163 studies met inclusion criteria, describing 50,683 ultrasound-guided BPBs, and 2261 adverse outcomes reported. The adverse outcomes reported included hemidiaphragmatic paresis/paralysis, dyspnea/desaturation, Horner's syndrome , hoarseness , vascular puncture/hematoma, postoperative neurological symptoms , local anesthetic systemic toxicity, and pneumothorax . Interscalene blocks accounted for 58 % of all reported adverse events, with hemidiaphragmatic paresis and Horner's syndrome being the most reported outcomes. Vascular puncture was more common in infraclavicular and axillary blocks. Terminology used to describe adverse outcomes included “complications,” “adverse outcomes,” “side effects,” or with no specific terminology. The terms used to describe the outcome for the same BPB type and adverse outcome varied across studies. These findings underscore the types of adverse events being studied and reported, and the variable nomenclature used to describe them. Future research will need to focus on a broader range of adverse events, and utilize a standardized terminology of adverse outcomes to improve comparability of future studies.