Acute viral bronchiolitis is a clinical syndrome with varying symptoms. In developed countries, bronchiolitis is the most common reason for hospitalisation in the first 12 months of life. 1,2 Up to 6% of these patients require admission to the paediatric intensive care unit (PICU). 3 It is characterised by inflammation and oedema of the tracheobronchial tree, along with increased mucus production and apoptosis of airway epithelial cells. 4 A diagnosis of bronchiolitis is based on medical history and physical examination. 5 The disease lacks a pathognomonic radiological pattern. 6 Radiographic features suggesting viral bronchiolitis when using chest radiography may include lung hyperinflation, peribronchial wall thickening often symmetrical and bilateral, lack of focal consolidation in the lungs,

BackgroundThe utility of the forced oscillations technique (FOT) in cystic fibrosis (CF) remains uncertain. The aim of this study was to explore the ability of lower‐frequency FOT indices, alone and after adjustment for the lung volume, to assess the extent of ventilation inhomogeneity in CF patients with varying disease severity.MethodsForty‐five children, adolescents, and adults with CF (age 6.9–27 years) underwent spirometry, FOT, and nitrogen multiple‐breath washout (N2‐MBW) measurements. The respiratory resistance and reactance at 5 Hz (Rrs5 and Xrs5, respectively) were recorded, and a novel FOT index, the specific respiratory conductance (sGrs), was computed as the reciprocal of Rrs5 divided by the functional residual capacity.ResultsThe sGrs correlated well with the lung clearance index (LCI) (Spearman's r: –.797), whereas the correlation of Rrs5 and Xrs5 with the LCI, albeit significant, was weaker (r: .643 and –.631, respectively). The sGrs emerged as the most robust predictor of LCI regardless of the severity of lung disease, as reflected by patients' age and lung function measurements. Most importantly, the relationship between sGrs and LCI remained unaffected by lung hyperinflation, as opposed to that of the LCI with the spirometric and standard FOT indices.ConclusionsIn CF patients, the FOT indices at 5 Hz and the novel, volume‐adjusted parameter sGrs, reflect the extent of lung involvement and the underlying ventilation inhomogeneity in a way comparable to N2‐MBW. Future research should explore the role of lower‐frequency FOT in assessing the severity and monitoring the progression of CF lung disease.

Objective: Acute viral bronchiolitis (AVB) is one of the most common viral infections and the most common lower respiratory tract infection in the first year of life. Current guidelines recommend that medical history and physical examination have the main role in the diagnosis of AVB. Lung ultrasound (LUS) has not been included in the diagnostic algorithm so far. The aim of this systematic review is to collect all available studies concerning the role of LUS in the diagnosis and management of AVB. Methods: PubMed - MEDLINE, Scopus and ScienceDirect databases were searched for trials reporting on LUS examination in the diagnosis and management of AVB in paediatric patients. Results: A total of seventeen studies matching our eligibility criteria were analyzed for the purposes of this review and their results were categorized into six major fields each one of them answering to a question. There are several LUS scores that evaluate the severity of sonographic findings in children with AVB. The findings on LUS and chest radiography are comparable and LUS has a significant role in further management of AVB in the Paediatric Emergency Department. LUS score is correlated to the clinical course of AVB and it can predict both the duration of hospitalization and the need for respiratory support. Conclusion: Current literature supports that LUS could have comparable efficiency with chest radiography concerning the diagnosis of AVB and it could predict the length of hospital stay and the need of oxygen supply.