Consideration of Cough Reflex Development When Ordering Modified Barium Swallow Studies in Infants

Area of Science:

• Pediatric Gastroenterology
• Neonatology
• Speech-Language Pathology

Background:

• Infants under 51 weeks post-menstrual age (PMA) often undergo modified barium swallow (MBS) studies to assess for silent aspiration (SA).
• SA is suspected due to a potential link with aspiration pneumonia, though young infants may lack a mature laryngeal cough reflex, making SA a common finding.
• The development of the laryngeal cough reflex is crucial for understanding SA resolution.

Purpose of the Study:

• To determine if SA resolves in infants around the expected emergence of the laryngeal cough reflex.
• To identify factors associated with SA resolution or persistence.
• To investigate the association between SA and lower respiratory infections (LRI), including aspiration pneumonia.

Main Methods:

• Retrospective chart review of infants under 51 weeks PMA who underwent MBS studies.
• Analysis of SA resolution rates at different time points.
• Statistical analysis to identify factors associated with SA resolution and correlation with LRI.

Main Results:

• 53.4% of infants under 51 PMA had SA on MBS.
• Only 33.3% of infants assessed by the expected cough reflex emergence showed SA resolution.
• SA resolution was less frequent in infants with obstructive sleep apnea (p=0.037).
• 71.4% of infants with follow-up MBS eventually resolved SA.
• No significant association was found between aspiration and LRI.

Conclusions:

• The laryngeal cough reflex may develop later than previously reported.
• Age should be a key consideration before ordering MBS solely for SA assessment in this population.
• Findings suggest no significant link between aspiration and LRI in young infants, warranting further prospective research.