Lung ultrasound for prediction of respiratory support in infants with acute bronchiolitis: A cohort study.

Objective: Respiratory tract infections are among the most common causes of morbidity and mortality worldwide. Acute bronchiolitis (AB) is the leading cause of hospital admission among infants. Clinical scores have proven to be inaccurate in predicting prognosis. Our aim was to build a score based on findings of lung ultrasound (LU) performed at admission, to stratify patients at risk of needing respiratory support (non-invasive and invasive ventilation).

Study Design: Prospective, multicenter study including infants <6 months of age admitted with AB. Point-of-care LU was performed on admission, and a score was calculated based on ultrasound findings (presence and localization of B lines, B line confluence and/or consolidations) and clinical data. Main outcome was need of respiratory support.

Results: A total of 145 patients were included in the study, with a median age of 1.7 months [IQR: 1.2-2.8], 47.6% were female. Mean duration of symptoms prior to admission was 3.1 days (SD 1.8). Fifty-six patients (39%) required non-invasive ventilation (NIV), 14 (9.7%) were transferred to PICU, and 3 needed invasive ventilation (3/145). Identification of at least one posterior consolidation >1 cm was the main factor associated to NIV (RR 4.4; [CI95%1.8-10.8]) The LU score built according to the findings on admission showed an AUC: 0.845(CI95%:0.78-0.91). A score ≥3.5 showed a sensitivity of 89.1% (CI95%:78.2-94.9%) and specificity of 56% (CI95%: 45.3-66.1%) CONCLUSIONS: Among infants below 6 months of age admitted with AB, point-of-care LU was a helpful tool to identify patients at risk of needing respiratory support.