Aspirating and nonaspirating swallow sounds in children: A pilot study

Background - Cervical auscultation(CA) may be used to complement feeding/swallowing evaluations when assessing for aspiration. There are no published paediatric studies that compare the properties of sounds between aspirating and non-aspirating swallows. Aim - To establish acoustic and perceptual profiles of aspirating and non-aspirating swallow sounds; and to determine if a difference exists between these two swallowing types. Methods - Aspiration sound clips were obtained from recordings using CA simultaneously undertaken with videofluoroscopic swallow study. Aspiration was determined using the Penetration-Aspiration Scale. The presence of perceptual swallow/breath parameters was rated by two speech pathologists who were blinded to the type of swallow. Acoustic data between groups were compared using Mann Whitney U-tests, while perceptual differences were determined by a test of two proportions. Combinations of perceptual parameters of 50 swallows (27 aspiration, 23 no aspiration) from 47 children (57% male) were statistically analysed using area under a receiver operating characteristic(aROC), sensitivity, specificity and positive and negative predictive values to determine predictors of aspirating swallows. Results - The combination of post-swallow presence of: wet breathing and wheeze; and absence of: GRS and normal breathing was the best predictor of aspiration (aROC 0.82, 95%CI 0.70 – 0.94). There were no significant differences between these two swallow types for peak frequency, duration and peak amplitude. Conclusion - Our pilot study has shown that certain characteristics of swallow obtained using CA maybe useful in the prediction of aspiration. However, further research comparing the acoustic swallowing sound profiles of normal children to children with dysphagia (who are aspirating) on a larger scale is required