Sucking vs swallowing coordination, integration and performance in preterm and term infants.
feeding; physiology; infant; preterm; Sensorimotor integration
Mammalian infants must be able to integrate the acquisition, transport, and swallowing of food in order to effectively feed. Understanding how these processes are coordinated is critical, as they have differences in neural control and sensitivity to perturbation. Despite this, most studies of infant feeding focus on isolated processes, resulting in a limited understanding of the role of sensorimotor integration in the different processes involved in infant feeding. This is especially problematic in the context of preterm infants, as they are considered to have a pathophysiological brain development and often experience feeding difficulties. Here, we use an animal model to study how the different properties of food acquisition, transport, and swallowing differ between term and preterm infants longitudinally through infancy in order to understand which processes are sensitive to variation in the bolus being swallowed. We found that term infants are better able to acquire milk than preterm infants, and that properties of acquisition are strongly correlated with the size of the bolus being swallowed. In contrast, behaviors occurring during the pharyngeal swallow, such as hyoid and soft palate movements, show little to no correlation with bolus size. These results highlight the pathophysiological nature of the preterm brain and also demonstrate that behaviors occurring during oral transport are much more likely to respond to sensory intervention than those occurring during the 'pharyngeal phase'.
Mayerl CJ;Edmonds CE;Catchpole EA;Myrla AM;Gould FDH;Bond LE;Stricklen BM;German RZ
Journal of Applied Physiology
2020
2020-10-15
journalArticle
<a href="http://doi.org/10.1152/japplphysiol.00668.2020" target="_blank" rel="noreferrer noopener">10.1152/japplphysiol.00668.2020</a>
Swallow Safety is Determined by Bolus Volume During Infant Feeding in an Animal Model.
Animal model; aspiration; children born; coordination; dysphagia; dysphagia; Feeding; laryngeal nerve lesion; low-birth-weight; Neonate; patent ductus-arteriosus; Performance; pharyngeal swallow; preterm; respiration
Feeding difficulties are especially prevalent in preterm infants, although the mechanisms driving these difficulties are poorly understood due to a lack of data on healthy infants. One potential mechanism of dysphagia in adults is correlated with bolus volume. Yet, whether and how bolus volume impacts swallow safety in infant feeding is unknown. A further complication for safe infant swallowing is recurrent laryngeal nerve (RLN) injury due to patent ductus arteriosus surgery, which exacerbates the issues that preterm infants face and can increase the risk of dysphagia. Here, we used a validated animal model feeding freely to test the effect of preterm birth, postnatal maturation and RLN lesion and their interactions on swallow safety. We also tested whether bolus size differed with lesion or birth status, and the relationship between bolus size and swallow safety. We found very little effect of lesion on swallow safety, and preterm infants did not experience more penetration or aspiration than term infants. However, term infants swallowed larger boluses than preterm infants, even after correcting for body size. Bolus size was the primary predictor of penetration or aspiration, with larger boluses being more likely to result in greater degrees of dysphagia irrespective of age or lesion status. These results highlight that penetration and aspiration are likely normal occurrences in infant feeding. Further, when comorbidities, such as RLN lesion or preterm birth are present, limiting bolus size may be an effective means to reduce incidences of penetration and aspiration.
Mayerl Christopher J; Myrla Alexis M; Gould Francois D H; Bond Laura E; Stricklen Bethany M; German Rebecca Z
Dysphagia
2020
2020-04-24
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
journalArticle
<a href="http://doi.org/10.1007/s00455-020-10118-x" target="_blank" rel="noreferrer noopener">10.1007/s00455-020-10118-x</a>
Changes in the coordination between respiration and swallowing from suckling through weaning.
aerodigestive; chin-tuck maneuver; deglutition; dysphagia; food transport; mammal; maturation; preterm; solid food; thickened infant formula; weaning
All mammals undergo weaning from milk to solid food. This process requires substantial changes to mammalian oropharyngeal function. The coordination of swallowing and respiration is a crucial component of maintaining airway function throughout feeding and matures over infant development. However, how this coordination is affected by weaning is unknown. In this study, we ask how changes in posture, neural maturation and food properties associated with the weaning affect coordination of respiration and swallowing in a validated infant pig model. We recorded seven piglets feeding before and during the weaning age with liquid milk in a bottle and in a bowl, and solid feed in a bowl. Using videofluoroscopy synchronized with respiration, we found (i) the delay in the onset of inspiration after swallowing does not change with head position, (ii) the delay is different between solid food and bowl drinking at the same age and (iii) the delay increases over time when bottle feeding, suggesting a maturational effect. Significant changes in aerodigestive coordination occur prior to and post-weaning, resulting in distinctive patterns for liquid and solid food. The interplay of maturational timelines of oropharyngeal function at weaning may serve as a locus for behavioural and life-history plasticity.
Bond Laura E; Mayerl Christopher J; Stricklen Bethany M; German Rebecca Z; Gould Francois D H
Biology letters
2020
2020-04
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
journalArticle
<a href="http://doi.org/10.1098/rsbl.2019.0942" target="_blank" rel="noreferrer noopener">10.1098/rsbl.2019.0942</a>