Acquisition of respiratory surface EMG: a systematic literature review of electrode configurations and methodological reporting

Abstract

BACKGROUND: Mechanical ventilation provides life-saving support to patients with respiratory failure, but inadequately tailored settings can lead to respiratory muscle dysfunction and poor patient outcomes. Surface electromyography (sEMG) offers a non-invasive modality to monitor respiratory muscle function. However, variability in acquisition setups limits the comparability of study findings and hinders broad clinical implementation. Therefore, we systematically appraised setup rationales and reporting quality in respiratory sEMG literature. METHODS: The MEDLINE ALL, Embase, and Web of Science databases were systematically searched on 19 September 2024 for studies reporting original respiratory sEMG data in adults during spontaneous breathing. sEMG methodology was extracted in accordance with the reporting guidelines of the International Society of Electrophysiology and Kinesiology and analyzed by target muscle and medical domain. RESULTS: 240 out of 402 unique articles were included. The diaphragm was the most studied respiratory muscle (61%) with 48 unique setups out of 160 descriptions. Diaphragm setups with small inter-electrode distances (IEDs) were most common (n = 138, 86%). Large IED setups were predominantly applied in ICU (n = 8, 36%) and COPD (n = 5, 23%) populations. Setups for non-diaphragmatic respiratory muscles typically featured one or two dominant positions grounded in methodological studies. Reporting quality was low with a median of 5 out of 10 recommended items documented. CONCLUSION: This review reveals substantial diversity of diaphragm sEMG setups, reflecting differences in clinical contexts and study populations. The setups for extra-diaphragmatic muscles were more consistent and methodologically grounded. Muscle- and context-specific guidelines are essential to improve consistency and support clinical implementation of respiratory sEMG.