Intestinal obstruction (ileus) types. Mesenteric thrombosis. Complications
Intestinal obstruction
Collectively, hernias, intestinal adhesions, intussusception and volvulus account for 80% of all mechanical obstructions, while tumours and infarction are generally the rest. Clinical picture includes pain, distention, vomiting and constipation. Surgery is usually required.
Remember: ileus is either mechanical, with a physical block (hernia, adhesions, volvulus, intussusception, tumour), or paralytic (adynamic), where peristalsis stops without a block, e.g. after abdominal surgery, in peritonitis, hypokalaemia or with opioids. Strangulation of a mechanical obstruction cuts the blood supply and leads to infarction.
Hirschsprung disease (1 in 5000 births) is a congenital disorder where the enteric neural plexus fails to properly develop causing loss of submucosal plexus and myenteric plexus meaning peristalsis is absent. Along with congenital hernias, this is one of the more common intestinal obstructions in newborns.
Mesenteric thrombosis
This is a blood clot in one of the veins draining or arteries supplying the intestines, it can affect the splenic vein, or superior or inferior mesenteric vessels. Clots to these veins can occur due to abdominal injury, clotting disorders, inflammatory bowel diseases, pancreatitis, liver cirrhosis and tumours.
Symptoms will include abdominal pain, bloating, diarrhea, vomiting and possibly fever with bloody stools.
Where we see an arterial blockage we will see ischemia and gangrene of the bowel wall.
Gross: haemorrhagic infarction of the small bowel (here from strangulation in an inguinal hernia; mesenteric thrombosis looks the same). The wall is swollen and dusky purple-red.
Image: “Haem infarction, small bowel” by Narraburra, CC0, via Wikimedia Commons.