Accuracy of Transthoracic Lung Ultrasound for Diagnosing Anesthesia-induced Atelectasis in Children

Background: The aim of this study was to test the accuracy of lung sonography (LUS) to diagnose anesthesia-induced atelectasis in children undergoing magnetic resonance imaging (MRI). Methods: Fifteen children with American Society of Anesthesiology's physical status classification I and aged 1 to 7 yr old were studied. Sevoflurane anesthesia was performed with the patients breathing spontaneously during the study period. After taking the reference lung MRI images, LUS was carried out using a linear probe of 6 to 12 MHz. Atelectasis was documented in MRI and LUS segmenting the chest into 12 similar anatomical regions. Images were analyzed by four blinded radiologists, two for LUS and two for MRI. The level of agreement for the diagnosis of atelectasis among observers was tested using the. reliability index. Results: Fourteen patients developed atelectasis mainly in the most dependent parts of the lungs. LUS showed 88% of sensitivity (95% CI, 74 to 96%), 89% of specificity (95% CI, 83 to 94%), and 88% of accuracy (95% CI, 83 to 92%) for the diagnosis of atelectasis taking MRI as reference. The agreement between the two radiologists for diagnosing atelectasis by MRI was very good (kappa, 0.87; 95% CI, 0.72 to 1; P < 0.0001) as was the agreement between the two radiologists for detecting atelectasis by LUS (kappa, 0.90; 95% CI, 0.75 to 1; P < 0.0001). MRI and LUS also showed good agreement when data from the four radiologists were pooled and examined together (kappa, 0.75; 95% CI, 0.69 to 0.81; P < 0.0001). Conclusion: LUS is an accurate, safe, and simple bedside method for diagnosing anesthesia-induced atelectasis in children.