Sucking, swallowing, and their coordination with breathing, are often compromised in preterm infants, yet are critical to their long-term health outcomes. Current work suggests that external oral sensory stimuli induce rhythmic sucking, and that such stimuli hold potential as rehabilitation strategies. However, our understanding of the impact of these interventions on aerodigestive function is limited because human preterm infants are a fragile research population, with restrictions on experimental manipulations. We also do not know the role that the degree of prematurity and the subsequent neurological maturation of the preterm infant brain plays in determining the effectiveness of oral stimulation in facilitating feeding. Thus, the translation of these promising results into effective interventions for promoting sustained oral feeding in preterm infants is inadequate. Using an animal model of preterm infants, we propose to test how nutritive stimulation, in the form of rhythmic milk delivery, functions as an intervention for improving aerodigestive function. We will test two factors that may determine the success of this intervention: the duration of intervention and degree of prematurity. We will apply the intervention for either a short term (early infancy) or for a longer term (entire infancy prior to weaning). Within each treatment duration, there will be two independent age groups, defined by respiratory status at birth: (1) capable of independent respiration or (2) requiring bubble CPAP ventilation support. We will compare these infants to bottle fed individuals who receive only non-nutritive stimulation and to individuals who are only bottle fed. We have proven and validated this model for studying aerodigestive function in preterm infants, as well as the interventions proposed. The experimental methods will include high-speed biplanar videoflurography, electromyography and respiration, from which we will extract outcome variables assessing airway protection, rhythmicity of respiration, sucking and swallowing, and coordination amongst these behaviors. The significance of this work is the determination of how, and at what age, oral stimuli change the function and the underlying physiology of preterm infant feeding- respiration coordination. By testing the relationship between infant neuromotor maturation and the effectiveness of stimulation-based treatment, this work will provide a basis for the subsequent development of new therapeutic interventions for neurological and physiological complications which affect feeding in all infants.

Poor ability to coordinate feeding and breathing compromises the short and long term health of the growing number of preterm infants born today. Using an animal model of these fragile human patients will test the effect oral sensory stimulation, a promising avenue for therapeutic interventions, on infants feeding safety over the course post-natal nervous system maturation. This project advances NIH’s mission by testing the potential of a specific intervention to improve preterm infant feeding and respiration, and therefore longer term health outcomes.