Paediatric acute abdomen

Red flags:

• Bilious vomiting (SBO)
• Recurrent projectile vomiting (pyloric stenosis)
• Baby hungry after vomiting (pyloric stenosis)
• Faltering growth
• Bloodstained vomit or stool
• Severe dehydration
• Failure to pass meconium
• Signs of peritonism

Initial management

• Fluid resus (correct hypovolaemia, hypoglycaemia, acid-base disturbance). Can initially give 10-20mL/kg of 0.9% NS
• NBM +/- NGT
• Bloods - FBE, UEC, LFT, BGL, coags, G+H, ?AXR
• Liaise w/ paeds surg

Specific diseases

Malrotation volvulus

• Usually presents during first four weeks
• Bilious vomiting
• Abdo discomfort
• Often initially well but deteriorate rapidly

Hirschsprung Disease

• Failure of migration of ganglionic precursor cells within the bowel
• Most commonly affects rectum/sigmoid
• Failure to pass meconium, bilious vomiting, dehydration (also consider meconium ileus as a complication of CF)
• Needs rectal biopsy
• Treat with resection of affected region, then pull-through of normal bowel. Good prognosis.
  • Complicated by Hirschsprung enterocolitis in about 25% of cases - bilious vomiting, explosive/foul-smelling stools, distended abdomen. Needs antibiotics and regular rectal washouts

Vomiting in newborn

• Overfeeding (most common by far) - related to feeds, generally bottle-fed
• GORD - small vomits, not related to feeds
• Pyloric stenosis (look for red flags above)
  • Palpable olive-sized mass in right hypochondrium
  • If no mass, get an USS
• Medical - systemic infection, cows milk protein allergy, gastroenteritis, poisoning

Hernias

• More common on right, generally indirect, more common in boys

Intussusception

• Colicky abdo pain, between 6 months and 2 years
• Most common at ileo-caecal junction
• 90% are idiopathic, otherwise consider Meckel's or polyps or lymphoma
• Severe colicky abdo pain, vomiting, palpable sausage-like mass in the abdomen, passage of redcurrant jelly stools (late)
• Resuscitate as above, including NGT. Confirm diagnosis with USS.
• Treat with air or fluid enema (success rate 75-95%, recurrence 10%)

Appendicitis

• Consider differentials - ovarian, urological, gastrointestinal