Intestinal obstruction & ileus Flashcards
What is intestinal obstruction
Mechanical disruption in the patency of the GI tract and flow of intestinal contents, resulting in a combination of emesis, absolute constipation and abdominal pain
What is ileus
slowing of gastrointestinal motility accompanied by distention, in the absence of a mechanical intestinal obstruction
What are the causes of small bowel obstruction
Duodenal atresia
Jejunal/ileal atresia or stenosis
Malrotation of the gut + volvulus
Meconium ileus
Intussusception
Strangulated inguinal hernia
Meckel’s diverticulum
What are the causes of large bowel obstruction
Meconium plug
Hirschsprung’s disease
Anorectal malformation: imperforate anus
Intussusception
Strangulated inguinal hernia
What are the causes of ileus
Paralytic ileus:
Gastroenteritis
Electrolyte imbalance e.g. hypokalaemia
Abdominal surgery
Reduced blood supply to intestines
What are the signs and symptoms of intestinal obstruction
Persistent bile stained vomiting
Delayed meconium passage
Abdominal distension
Abnormal bowel sounds
The more proximal the obstruction, the more prominent the vomiting and the sooner it becomes bile-stained (unless the obstruction is proximal to the ampulla of Vater)
The more distal the obstructions are more likely to cause significant abdominal distension
What investigations should be done for intestinal obstruction and ileus
Bedside: urine dip, stool culture, fecal calprotectin
Bloods: FBC, U&Es, CRP/ESR, calcium and bone profile, TFTs
Imaging: AXR
What do findings on AXR for obstruction suggest
Few dilated loops of bowel: proximal obstruction e.g. malrotation, jejunal atresia
Multiple dilated loops of bowel: distal obstruction e.g. ileal atresia, meconium ileus or plug, Hirschsprung’s or anal atresia
What is the management for intestinal obstruction
- IV fluid and electrolyte correction
- Treat the cause:
Atresia/stenosis: duodenoduodenostomy or laparotomy with primary resection and anastomosis (Jejunal)
Malrotation: Ladd’s proceudre
Meconium ileus: gastrograffin contrast, surgical decompression
Hirschsprung’s: rectal washout/bowel irrigation
Necrotising enterocolitis: Conservative and supportive for non perforated cases, laparotomy and resection in cases of perforation of ongoing clinical deterioration
What are the complications of intestinal obstruction
Small Bowel Obstruction:
- Intestinal ischaemia → infarction → necrosis → perforation → peritonitis
- Sepsis
- Multi-organ failure
- Intra-abdominal abscess
- Short bowel syndrome
Large bowel:
- Intestinal ischaemia → infarction → necrosis → perforation → peritonitis
- Sepsis
- Death
What is the prognosis for intestinal obstruction
SBO is medical emergency, and those who are treated in a timely manner have a very good prognosis
SBO is a major cause of morbidity and mortality, and it can be fatal in untreated patients due to its progression to intestinal necrosis, perforation, sepsis, and multi-organ failure.
What are the features of duodenal atresia/stenosis and what investigations should be done
Associated with Down’s syndrome (1/3) and other congenital malformations
AXR: double bubble sign
Contrast study for diagnosis
What are the features of jejunal atresia/stenosis and what investigations should be done
Multiple atretic segments of the bowel
AXR: air fluid levels
What are the features of meconium plug and what investigations should be done
Plus of inspissated meconium causing lower intestinal obstruction
Usually passes spontaneously
What is meconium ileus and what investigations should be done
Thick inspissated meconium, putty-like consistency
Becomes impacted in the lower ileum
Associated with cystic fibrosis
Delayed passage of meconium and abdominal distension
AXR: no fluid levels as meconium is viscid
PR contrast studies: may be therapeutic
Sweat test to confirm CF
If no response to PR contrast and NG N-acetyl cysteine -> requires surgery to remove plugs
What is meckel’s diverticulum and its rule of 2s
Congenital malformation of the bowel which causes painless massive rectal bleeding in children 1-2yo
(1 to) 2-years-old
2% population
2x more common in boys
2 feet from ileocecal valve
2 inches long
2 different mucosae (gastric and pancreatic)
What causes meckel’s diverticulum
2% of people have an ileal remnant of the vitello-intestinal duct (also known as omphalomesenteric duct)- a long narrow tube that joins the yolk sac to the midgut lumen of the developing foetus
It contains either gastric mucosa or pancreatic tissue i.e. can form gastric ulcers caused by acidity that bleed
The acid produced within the pouch can be released/ spilled causing ulcers or peritonitis
What are the signs and symptoms of meckel’s diverticulum
Most asymptomatic
Rectal bleeding - severe (neither bright red or true melaena) -> may cuase haemodynamic instability
May have intractable constipation
Intussusception, volvulus, meckel’s diverticulitis (mimics appendicitis)
Bowel obstruction -> cramps, pain, tenderness
Nausea and vomiting
What are the differentials for meckel’s diverticulum
Appendicitis - unlikely to have rectal bleeding, pt will be febrile & N+V
Intusception - peak age around 9m, will have colic pain and inconsolable crying
Anal fissure
Polyp
Clotting disorder
Peutz-Jeghers syndrome is a rare autosomal dominant disorder that is characterised by hamartomatous polyposis. Gastrointestinal symptoms first start becoming apparent at around 10 years of age.
What investigations should be done for meckel’s diverticulum
Abdo exam
Bedside: stool sample
Bloods: FBC
Imaging: USS, XR, Meckel’s scan
- A Technetium scan (Meckel’s Scan): increased uptake by ectopic gastric mucosa in 70% of cases
- Used if the child is haemodynamically stable with less severe or intermittent bleeding
What is the management for Meckel’s diverticulum
Asymptomatic (Incidental imaging finding)
NO treatment required
Detected during surgery for other reasons- prophylactic excision
Symptomatic
Bleeding- excision of diverticulum with blood transfusion (if haemodynamically unstable)
Obstruction- excision of diverticulum and lysis of adhesions
Perforation/ peritonitis- excision of diverticulum or small bowel segmental resection with perioperative antibiotics
Surgery usually performed laparoscopically
What are the complications of Meckel’s diverticulum
Haemorrhage
Intestinal obstruction
Umbilico-ileal fistulas
Perforation
What is the prognosis of Meckel’s diverticulum
Excellent if treated in a timely fashion
Most common complication is post-operative bowel obstruction (due to adhesions)