Bowel obstruction

Question 1

1) What is the commonest bowel obstruction - small intestine or large intestine?

Answer 1

1) Small

Question 2

1) What is third-spacing?
2) What causes third-spacing?
3) What are the 2 consequences of third-spacing?

Answer 2

1) Abnormal loss of fluid
2) Fluid secreted from the GI tract cannot reach the colon in the case of a bowel obstruction, and hence it cannot be reabsorbed. As a result, there is fluid loss from the intravascular space into the gastrointestinal tract
3) Hypovolemia and shock

Question 3

1) What are the 3 main causes of a bowel obstruction, and which part of the bowel does it affect (small or large)?
2) Name 2 other causes

Answer 3

1) Adhesions (small bowel), hernias (small bowel) and malignancy (large bowel)
2) Volvulus (large bowel), diverticular disease, strictures, intussusception, Crohn’s disease

Question 4

1) What are abdominal adhesions?
2) Name 2 causes of adhesions

Answer 4

1) Pieces of scar tissue that bind the abdominal contents together.
2) Abdominal or pelvic surgery (particularly open surgery), peritonitis , abdominal or pelvic infections , endometriosis

Question 5

1) What is a closed loop obstruction?
2) Name a cause of a closed loop obstruction

Answer 5

1) Situation where there are two points of obstruction along the bowel; meaning that there is a middle section sandwiched between two points of obstruction
2) Adhesions, hernias , volvulus, a single point of obstruction in the large bowel, with an ileocaecal valve that is competent

Question 6

Name 2 ways a bowel obstruction would present

Answer 6

• Vomiting (particularly green bilious vomiting)
• Abdominal distention
• Colicky abdominal pain
• Absolute constipation and lack of flatulence

Question 7

1) What is the key abdominal x-ray findings in a bowel obstruction?
2) What is usually required to confirm the diagnosis of bowel obstruction and establish the site and cause of the obstruction?

Answer 7

1) Distended loops of bowel
2) Contrast abdominal CT scan

Question 8

What is the definitive management of a bowel obstruction?

Answer 8

Surgery (either laparoscopy or laparotomy) to correct the underlying cause

Question 9

What is the initial management of a bowel obstruction?

Answer 9

• Nil by mouth
• IV fluids
• NG tube with free drainage