Point-of-Care Lung Ultrasound to Evaluate Lung Isolation During One-Lung Ventilation in Children: A Blinded Observational Feasibility Study

BACKGROUND: Minimally invasive thoracic surgical techniques require effective lung isolation using one-lung ventilation (OLV). Verification of lung isolation may be confirmed by auscultation, visual confirmation using fiberoptic bronchoscopy (FOB), or more recently, point-of-care ultrasound (POCUS). The aim of this study was to prospectively compare lung ultrasound with clinical auscultation to confirm OLV before thoracic surgery in pediatric patients. METHODS: This prospectively blinded feasibility study included 40 patients ranging in age from 0 to 20 years. After confirmation of lung separation by the primary anesthesia team using FOB, the sonographer and the auscultator, both blinded to the laterality of surgery and lung separation, entered the operating room. The sonographer evaluated for pleural lung sliding and the auscultator listened for breath sounds. Successful lung separation was definitively confirmed by direct visualization of lung collapse during the operation. RESULTS: In confirming effective single-lung ventilation, lung ultrasound had a diagnostic accuracy of 95% (95% confidence interval [CI], 82.7%–98.5%). In contrast, auscultation could only reliably confirm lung isolation with 68% accuracy (95% CI, 51.5%–80.4%). The McNemar test showed a statistically significant difference between the use of lung ultrasound and auscultation ( P < .001). The median time to perform ultrasonography was 67 seconds (interquartile range [IQR], 46–142) and the median time to perform auscultation was 21 seconds (IQR, 10–32). CONCLUSIONS: Based on the initial results of our feasibility trial, lung ultrasound proved to be a fast and reliable method to verify single-lung ventilation in pediatric patients presenting for thoracic surgery with a high degree of diagnostic accuracy.