Clinical accuracy and reliability of point-of-care ultrasound for perioperative diaphragmatic assessment: a scoping review.

Background

Diaphragmatic dysfunction contributes to perioperative respiratory morbidity. Point-of-care ultrasound enables noninvasive bedside assessment of diaphragmatic structure and motion and is increasingly used in perioperative practice. However, its diagnostic performance and measurement reliability in this setting have not been systematically evaluated. This scoping review aimed to map the available evidence, with emphasis on reliability, reproducibility, and agreement with reference standards.

Methods

A scoping review was conducted in accordance with Joanna Briggs Institute methodology and reported as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. A protocol was registered on the Open Science Framework. MEDLINE, MEDLINE ePubs and In-Process Citations, Embase, Scopus, Web of Science, and Cochrane databases were searched. Eligible studies included adult or paediatric surgical patients undergoing perioperative diaphragmatic ultrasound. Data were charted on study characteristics, ultrasound techniques, reference standards, and measures of diagnostic accuracy and inter- and intra-observer agreement.

Results

Nineteen studies (712 patients) were included, most being prospective observational and published after 2015. In adults, diaphragmatic ultrasound showed generally positive, although variable, correlations with spirometry, transdiaphragmatic pressure, electrophysiological measures, neuromuscular recovery, and arterial blood gas-based weaning criteria. Thresholds for excursion and thickening varied across studies. Inter- and intra-observer agreement was generally good to excellent, including among operators with limited training. In paediatric populations, ultrasound demonstrated high diagnostic accuracy and strong agreement with fluoroscopy, with excellent interobserver reliability.

Conclusions

Perioperative diaphragmatic ultrasound shows acceptable reliability and agreement with reference standards. Heterogeneity in techniques and outcomes limits comparability. Standardisation and outcome-linked studies are needed to define its role.