Respiratory Variation of Internal Jugular Vein Diameter as a Novel Ultrasonographic Marker of Disease Severity in Infants With Acute Bronchiolitis: A Prospective Observational Cohort Study
Respiratory Variation of Internal Jugular Vein Diameter as a Novel Ultrasonographic Marker of Disease Severity in Infants With Acute Bronchiolitis: A Prospective Observational Cohort Study
This prospective observational cohort study evaluates whether respiratory-cycle variation in internal jugular vein (IJV) diameter, measured by point-of-care ultrasound, correlates with clinical disease severity in infants 1-23 months of age presenting with acute bronchiolitis. Using a standardized M-mode protocol, the IJV Variability Index ([IJVmax-IJVmin]/IJVmax x 100) will be calculated and compared with the Wang Bronchiolitis Severity Score, four additional validated clinical severity instruments (Modified Tal Score, Respiratory Distress Assessment Instrument, Kristjansson Respiratory Score, Respiratory Assessment Change Score), oxygen saturation, respiratory rate, need for high-flow nasal cannula or supplemental oxygen, pediatric intensive care unit admission, and length of hospital stay. Concurrent lung and diaphragm point-of-care ultrasound will be performed to build a multimodal ultrasound severity model. No intervention is assigned; all ultrasound assessments are performed in addition to standard clinical care and do not alter treatment decisions.
Inclusion Criteria:
Exclusion Criteria:
emre.gungor@ogu.edu.tr+90 222 239 2979 ext. 5214
Bronchiolitis is among the leading causes of hospitalization in infants under 2 years of age. Existing clinical severity scores show limited inter-observer agreement and weak correlation with oxygenation. Point-of-care ultrasound (lung ultrasound, diaphragm ultrasound) has been studied as an adjunct severity marker in bronchiolitis. Still, respiratory-cycle variability of the internal jugular vein (IJV) diameter has not previously been investigated in this population. A prior reliability study in healthy children demonstrated that right internal jugular vein (RIJV) diameter can be reliably measured by M-mode ultrasound and does not vary significantly across the respiratory cycle in the absence of respiratory distress; the study authors explicitly proposed that RIJV diameter and its respiratory variation be investigated as a surrogate marker of pulmonary function in children with respiratory distress. This study extends that proposed application to infants with acute bronchiolitis. Eligible infants aged 1-23 months meeting AAP (2014) clinical criteria for acute bronchiolitis will undergo a standardized ultrasound protocol (45-degree head elevation, linear probe, right internal jugular vein imaged approximately 1 cm cephalad to the sternoclavicular junction, B-mode identification followed by M-mode measurement of maximal inspiratory and expiratory diameters) performed by a blinded, trained sonographer. We will record concurrent clinical severity scoring, lung ultrasound, and diaphragm ultrasound (excursion, thickening fraction). The primary analysis will test the correlation between the IJV Variability Index and the Wang Bronchiolitis Severity Score; secondary analyses will examine correlations with additional validated severity scores, physiologic parameters, and clinical outcomes (respiratory support escalation, length of stay), as well as inter-/intra-observer reliability and the discriminative performance of a multimodal point-of-care ultrasound model.
emre.gungor@ogu.edu.tr+90 222 239 2979 ext. 5214