Bowel Obstruction Flashcards
Give some causes of small bowel obstruction
Adhesions
Hernia - incarcerated
Gallstone ileus
Tumours (ileocecal junction)
Give some causes of large bowel obstruction
Colorectal tumours
Sigmoid volvulus
Chronic diverticular disease
Acute diverticular disease
Define mechanical obstruction
Physical obstruction of a part of the bowel
How does a sigmoid volvulus appear on plain radiograph?
Inverted U or rugby ball
What happens in closed loop obstruction?
The ileocaecal valve prevents reflux of the large bowel contents, so the large bowel contents distend the caecum
Define a functional obstruction
Signs of a physical obstruction but there isn’t one. Usually occur post-surgery or from metabolic disorders.
Describe paralytic ileus
Obstruction of the intestine due to paralysis of the intestinal muscles
What can cause paralytic ileum?
Peritonitis Blood in the abdomen Opiates Handling of the bowel during surgery Electrolyte imbalance (hypokalaemia)
How do you resolve paralytic ileum?
Treat the cause
What is pseudo-obstruction?
Symptoms of mechanical obstruction are present but there is no cause found.
What causes pseudo obstruction?
Trauma (injury to the smooth muscle or nervous system)
Anti-cholinergic drugs
Anti-parkinsonism drugs
Renal failure
How will someone with an intestinal obstruction present?
Abdominal pain (colicky) Vomiting Absolute constipation Dysphagia Abdominal distension
What symptoms are more prevalent in small bowl obstruction?
Vomiting first
Less abdominal distension
Pain is felt higher up in the abdomen
What symptoms are more prevalent in large bowel obstruction?
More gradual onset
More normal bowel sounds
Constipation occurs first and then faeculant vomiting
Rectal bleeding
What investigation would you not do for an obstruction or perforation?
Contrast study as it could leak into the abdomen.
What investigations would you do for an obstruction?
FBC, U+Es - electrolyte imbalance
AXR
CT scan
What are the supportive measure for bowel obstruction?
NBM
NG tube to decompress the stomach
Analgesia
IV Fluids
How can you detect improvement with supportive management?
Decreasing nasogastric aspirates
Decreasing pain
Passage of flatus
When would you perform surgery in obstruction?
Strangulation
Closed loop obstruction
Failure of conservative therapy
Tumour
Define closed loop obstruction
Two points of the bowel are obstruction in a single location, which leads to the formation of a closed loop.
What is a Hartmann’s Procedure?
Resection of the rectosigmoid colon with closure of the rectal stump and the formation of an end colostomy.
What is the difference between closed loop and open loop obstruction?
Closed - competent ileocaecal valve, so pressure keeps increasing which can lead to bowel wall ischaemia, necrosis and perforation.
Open - incompetent ileocaecal valve, so there is relief of colonic pressure and the contents reflux into the ileum so can present like a small bowel obstruction
What is the prognosis for large bowel obstructions?
Overall mortality = 10%
Caecal perforation and faecal peritonitis = 20% mortality
