Characterizing the esophageal function of infants in the NICU.

Infants admitted in the neonatal unit commonly present with feeding problems such as decreased oral intake and feeding intolerance. These infants may suffer from complex diseases such as prematurity or congenital malformations. The origin of these feeding problems may be disease-specific or may be secondary to many factors such as severity of the illness, concomitant medication and surgical interventions.

“Healthy” preterm infants may have an immature nervous system leading to immature oral intake, and failure to coordinate sucking, swallowing and breathing. They may also have an immature motor gastro-intestinal function. Infants with bronchopulmonary dysplasia or central nervous system lesions are particularly prone to feeding problems. Recently, developmental changes in pharyngoesophageal physiology in the preterm infant were described explaining poor feeding in infants under 34 weeks. The physiology of distal esophageal motility has been described in healthy, preterm infants using water perfused manometry, but data on preterm infants with associated pathology are very limited.

Term infants with severe congenital malformations also often present with feeding problems. In some cases, underlying respiratory, neurological or cardiac pathology impedes the ability to take oral feeds. In children with esophageal atresia, motility disorders are primarily due to the intrinsically disturbed development of the esophagus. End-to-end anastomosis of the esophagus can disturb vagal innervations, vascular supply or cause traction on the lower esophagus. In infants with congenital diaphragmatic hernia, multiple factors may play a role in the disturbed gastro-esophageal function leading to poor feeding. Development and position of lungs, stomach and lower gastrointestinal tracts are abnormal in those patients. Moreover, repositioning of the abdominal organs into the abdominal cavity can result in disorders based on numeric manometric parameters.

For 15 years, we have had a unique setting of highly specialized clinical units focusing on pharyngeal as well esophageal dysphagia within the University Hospitals of Leuven. The current PhD project is part of an ongoing international collaboration between the KU Leuven (Experimental ORL, N Rommel) and the University of Adelaide, Australia (School of Paediatrics and Reproductive Health, T Omari) focusing on paediatric dysphagia. For three years, the clinical research has been expanded to adult dysphagia and become part of the Translational Research Centre for Gastrointestinal Disorders (TARGID). With this project we are now expanding the research to neonates.