Intussusception in Infants and Children

Intussusception is a pediatric surgical emergency in which one segment of intestine telescopes into an adjacent segment, causing obstruction and ischemia. It is the most common cause of intestinal obstruction in children between 3 months and 3 years of age, and early recognition is critical to prevent bowel necrosis and perforation.

Definition

• Intussusception: telescoping of a proximal segment of bowel into a distal segment, most often at the ileocecal junction.
• The invaginated bowel pulls mesentery and blood vessels with it, producing venous congestion, edema, ischemia, and — if untreated — perforation.

Pathophysiology

• Telescoping of proximal bowel into distal bowel obstructs the lumen.
• Venous congestion develops as mesentery is dragged into the intussusception, worsening edema and obstruction.
• Arterial compromise follows, leading to ischemia and possible perforation.
• Bowel wall inflammation and edema produce the classic sausage-shaped mass and currant jelly stools.

Risk Factors

• Age: 3 months to 3 years, with a peak at 5–9 months.
• Sex: more common in males (2:1 male-to-female ratio).
• Anatomical lead points: Meckel’s diverticulum, polyps, tumors, Henoch-Schönlein purpura (HSP).
• Infection: viral gastroenteritis, especially rotavirus.
• Immunization: small increased risk within 7 days of the first rotavirus vaccine dose — benefits still outweigh the risk.
• Meckel’s diverticulum is a common lead point in older children.

Clinical Manifestations

• Sudden, colicky abdominal pain — the hallmark. Infant draws knees to chest and cries intermittently.
• Paroxysmal crying with peristaltic waves; infant may appear well between episodes.
• Vomiting — occurs early and may become bilious as obstruction progresses.
• Currant jelly stools — red, gelatinous, mucus-filled; indicate intestinal ischemia/necrosis (often a late sign).
• Sausage-shaped abdominal mass, typically in the right upper quadrant.
• Dehydration signs: decreased urine output, sunken fontanelle, dry mucous membranes.
• Perforation signs: severe distension, rigidity, fever.

Diagnosis

• History and physical exam first. The classic triad of colicky pain, currant jelly stools, and a sausage-shaped mass is present in fewer than 50% of cases.
• Abdominal ultrasound — gold standard; shows a target sign or pseudokidney sign.
• Abdominal X-ray — may show obstruction or a meniscus sign.
• Contrast enema (air or barium) — both diagnostic and therapeutic; shows a “coiled spring” appearance.

Management

• Air or barium enema is first-line in stable children; enema pressure reduces the intussusception.
• Surgical reduction is required if the enema fails or the child is unstable. Resection is performed if bowel is necrotic.

Nursing Interventions

• Assess for bowel perforation: severe distension, rigidity, fever, tachycardia → emergency surgery.
• Monitor for sepsis: fever, tachycardia, hypotension.
• Maintain NPO status to prevent aspiration and prepare for possible surgery.
• Administer IV fluids to correct dehydration; monitor strict intake and output.
• Administer IV antibiotics if bowel ischemia is suspected or confirmed.
• Provide comfort measures — positioning, swaddling, pain relief.
• Monitor for recurrence after enema reduction (approximately 10%).

Complications

• Bowel ischemia and necrosis — most serious; requires surgical resection.
• Bowel perforation — life-threatening; requires emergency surgery.
• Sepsis — a serious sequela of perforation.
• Recurrence — approximately 10% after enema reduction.

Exam Traps

• Do not ignore currant jelly stools — they indicate ischemia/necrosis and may be a late sign.
• Do not confuse with gastroenteritis — gastroenteritis features diarrhea, not colicky episodic pain with a palpable mass.
• Do not confuse with malrotation with volvulus — malrotation is more common in neonates and presents with bilious vomiting.
• Do not delay diagnosis — intussusception is a surgical emergency.

Key takeaways

• Intussusception is the most common cause of intestinal obstruction in children 3 months to 3 years, most often at the ileocecal junction.
• Classic findings: colicky pain with knees drawn up, currant jelly stools, and a sausage-shaped RUQ mass — but the full triad appears in <50% of cases.
• Ultrasound (target/pseudokidney sign) is the diagnostic gold standard; air or barium enema is both diagnostic and first-line treatment.
• Priority nursing actions: NPO, IV fluids, monitor for perforation and sepsis, and watch for recurrence (~10%) after enema.
• Currant jelly stools and signs of peritonitis indicate ischemia — escalate immediately.