Nutrition, Gastrointestinal, and Fluid/Electrolyte Disorders
Balance substrate, fluid, and surgical warning signs
Nutrition begins with parenteral support in very preterm infants, then advances to human milk. Trophic feeds promote gut maturation. Necrotizing enterocolitis presents with abdominal distension, bloody stools, and pneumatosis; management includes stopping feeds, antibiotics, and surgical consultation. Bilious emesis in a newborn is a surgical emergency until malrotation with volvulus is excluded. Fluid requirements depend on gestational age, insensible losses, and phototherapy. Term infants often start at 60–80 mL/kg/day, while extremely preterm infants may need more, with careful sodium and potassium monitoring. Hypoglycemia is common in growth-restricted and infant-of-diabetic-mother infants.
Traps: treating bilious emesis as reflux; missing NEC because the abdominal radiograph is initially normal; and giving free water to correct hypernatremia. Also distinguish physiologic jaundice from pathologic hemolysis.
Worked example: a 1.5-kg preterm infant receives parenteral nutrition and trophic feeds. On day 5, the abdomen is distended and a radiograph shows pneumatosis. Feeds are stopped, antibiotics are started, and surgery is consulted.
Rule of thumb: “Bilious emesis is malrotation until proven otherwise; stop feeds and image.”