Neuromotor markers of esophageal motility in feeding intolerant infants with gastroschisis

Background: Feeding problems in neonates with gastroschisis are commonly attributed to foregut dysmotility. However, the dysmotility mechanisms are not well understood. Objective: Our aim was to differentiate the pharyngoesophageal motility characteristics in neonates with gastroschisis compared with the controls. Specifically, the characteristics of swallowing, upper esophageal sphincter (UES), esophageal body, and lower esophageal sphincter (LES) were evaluated during basal state and upon provocation. Patients and Methods: Surgically repaired and recovered study infants with persistent feeding difficulties (n = 8; 36 +/- 2 weeks gestational age) and controls (n = 8; 38 +/- 2 weeks gestational age) were evaluated at 40 2 weeks and 42 +/- 2.5 weeks postmenstrual age, respectively. The basal and adaptive pharyngoesophageal motility characteristics were evaluated using a specially designed esophageal motility catheter with UES and LES sleeves and pneumohydraulic micromanometric water perfusion system at the crib side. Analysis of variance, chi-square, and t tests were applied; data are shown as mean +/- standard deviation, and P < 0.05 was considered significant. Results: Birth weight was less in gastroschisis (P < 0.03, vs controls) and length was less at motility study (P < 0.01, vs controls). The study group (vs controls) needed prolonged respiratory support (21 +/- 23 vs 1 +/- 2 days; P < 0.001) and prolonged gavage feeding (167 +/- 100 vs 9 +/- 16 days; P < 0.01). Compared with the controls, the gastroschisis group had lower frequency (P < 0.05) and poor propagation of spontaneous swallows (P < 0.001), UES relaxation time was shorter (P < 0.05), rate of relaxation was faster (P < 0.001), and esophageal peristaltic propagation velocity was slower (P < 0.05). Upon esophageal provocation with air and liquids, frequency occurrence of the esophageal reflexes was low (P < 0.05) with respect to primary peristalsis, secondary peristalsis, UES contractile reflex, and LES relaxation reflex. Conclusions: In gastroschisis feeding milestones and respiratory milestones were delayed, basal pharyngoesophageal peristaltic failure was common, adaptive peristaltic reflexes were less frequent and failed to occur, and frequency occurrences of UES and LES responses were impaired. These neuromotor markers may provide clues to define the esophageal motor function abnormalities in infants with an abnormality thought to be limited to the intestine.