Gastrointestinal and Nutrition
Core concepts
Understand neonatal nutrition: colostrum and breast milk benefits, feeding cues, and the risks of feeding intolerance in preterm infants. Know necrotizing enterocolitis (NEC) - risk factors (prematurity, formula feeding, hypoxia), presentation (abdominal distension, bloody stools, feeding intolerance, lethargy), and management (stop feeds, decompress, antibiotics, surgery if perforation). Grasp bilirubin metabolism and physiologic versus pathologic jaundice, including breastfeeding jaundice versus breast-milk jaundice. Know the significance of delayed meconium passage and the workup of vomiting in the newborn (bilious vomiting suggests obstruction until proven otherwise). Understand gastroesophageal reflux versus pyloric stenosis versus malrotation.
Traps
Questions test the rule that bilious vomiting in a newborn is a surgical emergency until malrotation or volvulus is excluded. Another trap: distinguishing physiologic jaundice (appears after 24 hours, peaks by days 3-5) from pathologic jaundice (before 24 hours, rapid rise). Also beware assuming all feeding intolerance is benign in a preterm infant.
Worked example
A 3-week-old has projectile nonbilious vomiting and an olive-shaped mass. Rule of thumb: pyloric stenosis presents at 2-6 weeks with nonbilious projectile vomiting and hypochloremic metabolic alkalosis; correct electrolytes before surgery.
Study focus
Differentiate benign feeding issues from surgical and metabolic emergencies.