Intussusception Flashcards
What is Intussusception
Intussusception is the invagination of a segment of bowel into another immediately adjacent to it, usually in a proximal to distal direction
•Could also occur in a retrograde manner
•It is a cause of occlusive-strangulation type of intestinal obstruction
•Children in Africa often present late
•Surgery could be the only option despite nonoperative reduction being the gold-standard
Epidemiology of Intussusception
Intussusception is the commonest cause of intestinal obstruction in infants and toddlers
•The second most common cause of acute abdomen in children.
•Incidence : 1.5 -4 per 1000 live births
•Male to female ratio is 2:1 to 3:2
Seen in all age groups, however common between age of 3 months - 2 years, peaks at 6 -9 months and rare after 5 years
•Has seasonal variations that correlate with viral infections (Jan/ July)
•Could also occur in adults and even in utero.
Classification: Based on location.
•Ileo-colic(75-85% of cases)
•Ileoileocolic- 2nd most common(10%)
•Ileoileal; jejuno-jejunal
•Colocolic; caeco-colic
Classification based on etiology.
1)Idiopathic or primary intussusception— 85-95%
Predisposing factors
•Gastroenteritis e.g. rotaviral
•Respiratory tract infection e.g adenoviral
•Commencement of complementary diet
•Immunization
1)Secondary intussusception— 4%
- There is a background pathology in the bowel referred to as a pathologic leadpoint
3). Postoperative - 1%
- After laparotomy, thoracotomy
Common pathologic leadpoints
•Meckel’s diverticulum – most common globally
•Intestinal polyps
•Intestinal duplications
•Haemangiomas, lymphomas, lymphosarcomas
•Henoch-Scholein purpura with submuc. Hematoma
•Cystic fibrosis with inspissated meconium
•Ectopic gastric/ pancreatic mucosa
•Worm infestation
Pathophysiology
•Imbalance of longitudinal forces along the bowel wall sets off intussusception
•This may be caused by a mass acting as a lead point or result from a disorganized pattern of peristalsis
•A kink develops in the abnormal portion of the intestine, thus creating a fulcrum for infolding
•Intussusceptum is pulled further into the distal segment by peristalsis, pulling the mesentery along with it and trapping the vessels.
•If not reduced, oedema, bowel obstruction, and ischaemia ensue with necrosis of bowel.
Sequelae
•Compressed mesentery (lymphatics and blood vessels)
•Lymphatic & venous obstruction; capillary congestion and rupture
•Eventual arterial compromise leads to ischaemia, necrosis /gangrene and/or perforation.
Clinical features: Classical triad
(occurs only in about one third of patients).
•Abdominal pain: sudden onset, colicky, manifests as paroxysmal inconsolable cry
•Vomiting
- Initially non-bilious ( reflex)
- Then bilious ( from intestinal obstruction)
•Red-currant jelly stools: passage of mucus and blood per rectum.
Examination
•Usually in a well nourished, healthy infants
•Palpable abdominal mass: periumbilical, sausage shaped (often in the RUQ but can be anywhere), felt in the rectum or seen at the perineum (prolapsed intussusception)
•Dance’s sign: emptiness in the RIF
•Lethargy and abdominal distension are late signs
•DRE:
- Anal protrusion ( prolapsed intussusception)
- Apex of intussusception felt
Differential Diagnosis
•Gastroenteritis; Dysentery
•Rectal Prolapse
Investigations
•Abdominal ultrasound scan – gold-standard
•Plain abdominal radiographs
•Barium enema
•FBC, serum E/U/CR, GXM blood
Abdominal ultrasound:
•Target sign – on transverse/cross-sectional view
•Pseudo-kidney sign – on longitudinal view
•May help detect a pathologic leadpoint
Plain abdominal X-ray
•May be normal
•May show a soft tissue peri-umbilical mass
•May show paucity/absence of gas in the RLQ
•May show features of intestinal obstruction
- multiple air-fluid levels with paucity of rectal gas on erect view
- centrally-located dilated bowel loops on supine view
Barium enema
•Now obsolete
•Done for patients who have no signs of peritonitis or gangrene.
•It shows coiled-spring sign
•This procedure could be therapeutic
Treatment
•Resuscitation
•Non-operative reduction: gold standard
•Hydrostatic reduction: saline, lactated ringers, barium
•Pneumatic reduction: Air enema
•Operative reduction:
•Hutchinson’s manoeuvre – manual reduction by milking
•Bowel resection & anastomosis/ stoma
Indications for operative reduction
•Peritonitis/ air under the diaphragm
•Failed nonoperative reduction
•2 or more recurrences after nonoperative reduction
•Presence of pathologic leadpoint
•Postoperative intussusception
•Intussusception in older children (>5yrs) or adult
Indications for bowel resection:
•Bowel gangrene
•Bowel perforation
•Iatrogenic bowel injury
•Pathologic leadpoint
•Irreducibility
Postoperative Intussusception
•May occur after abdominal or thoracic surgeries
•It is commonly due to differential return of peristalsis following ileus
•Occurs about 6 – 10 days postop
•Usually ileoileal
•Usually painless
•Early postop adhesion is a differential
•Abdominal USS is diagnostic
•Definitive treatment is operative reduction
Adult Intussusception
•Usually secondary to bowel tumours
•Small bowel – benign
•Large bowel – malignant
•Diagnosed on radiological imaging or at surgery
•Definitive treatment is bowel resection and anastomosis/ stoma
