Paediatric Surgery
What the exam tests
This domain covers neonatal bowel obstruction, pyloric stenosis, intussusception, Hirschsprung disease, paediatric hernias and testicular torsion.
Core rules
- Bilious vomiting in a neonate is malrotation with midgut volvulus until excluded; it is a surgical emergency.
- Pyloric stenosis presents at about 3 to 6 weeks with projectile non-bilious vomiting and a hypochloraemic, hypokalaemic metabolic alkalosis. Correct fluids and electrolytes before pyloromyotomy.
- Intussusception presents with colicky pain, drawing up the legs and redcurrant-jelly stool; air or contrast enema reduction is used in stable children without peritonitis.
- Hirschsprung disease causes delayed meconium passage and abdominal distension; diagnosis is by rectal biopsy showing aganglionosis.
- Examine both groins in any infant with vomiting or irritability; incarcerated hernia and torsion are time-critical.
Worked example
A 6-week-old boy has projectile vomiting after feeds and a palpable olive-shaped mass. Biochemistry shows hypochloraemic hypokalaemic metabolic alkalosis. He receives intravenous fluid and electrolyte correction until chloride and bicarbonate normalise, then undergoes pyloromyotomy.
Traps
Operating before correcting alkalosis and dehydration; missing malrotation in a neonate with bilious vomiting; failing to examine the groins; and reducing an intussusception in a child with peritonitis.