Swallowing function and medical diagnoses in infants suspected of Dysphagia

There has been an increase in infant swallowing disorders as a result of improved survival for infants born prematurely or with life-threatening medical disorders. These infants often have multiple health issues and an increased risk of respiratory complications. However, there is little understanding of the biomechanics of infant swallowing disorders. Therefore, the objectives of this study were to determine 1) the percentage of dysphagic infants who experience laryngeal penetration, aspiration, or nasopharyngeal backflow; 2) reasons for laryngeal penetration/aspiration; 3) whether infants with laryngeal penetration/aspiration clear their airway; and 4) the relationship between swallowing disorders and medical diagnoses.

Patients included 43 infants who were referred for videofluoroscopic swallowing studies in a university-affiliated pediatric medical center. Medical charts were reviewed. The videofluoroscopic swallowing studies were recorded on videotape, and each swallow was analyzed for laryngeal penetration, aspiration, nasopharyngeal backflow, cough, airway clearance, and reason for penetration/aspiration. Statistics included chi2 for nonparametric data and measures of central tendency for numeric/timing data.

More than half of the infants experienced laryngeal penetration, aspiration, or nasopharyngeal backflow; however, the first occurrence of these events was after multiple swallows. Only 3 infants experienced laryngeal penetration and aspiration on the first swallow and all 3 had an absent pharyngeal response. Premature infants experienced significantly more nasopharyngeal backflow. Material in the pyriform sinuses before pharyngeal swallowing was associated with penetration/aspiration. In episodes of laryngeal penetration, all patients were able to clear their airway during the swallow without a cough. Almost all infants (8 of 9) who aspirated did not cough or clear their airway.

This study demonstrated that most infants suspected of dysphagia showed overt abnormalities: laryngeal penetration, aspiration, and/or nasopharyngeal backflow on the videofluoroscopic swallowing study. Most of these infants did not demonstrate abnormalities in the first few swallows but displayed deterioration in swallowing function as they continued to feed. Thus, radiographic assessments in infants must examine multiple swallows. The high incidence of silent aspiration demonstrates the necessity of a videofluoroscopic assessment to evaluate swallowing function in these infants.