Bowel obstructions

Question 1

What is pathology of small bowel obstruction?

Answer 1

Obstruction of bowel leads to blockage + build up of fluids above the blockage.

Increase pressure then causes blood vessels to be compressed.

The compressed vessels cant supply blood resulting in ischaemia + necrosis.

Question 2

Risk factors of small bowel obstruction?

Answer 2

Adhesions due to surgeries of abdomin
Hernias
Malignancy
Crohns Disease

Question 3

Symptoms of small bowel obstruction?

Answer 3

Pain higher in abdomen than LBO
Vomiting occur earlier in SBO than LBO
Less abdominal distention than LBO
Constipation happens late in SBO
Increased bowel sounds

Question 4

Diagnosis of small bowel obstruction?

Answer 4

Abdominal X-RAY:
-Show gas shadows around lumen
-No gas in large bowel
- will see distended loops
-May see fluids

Question 5

Large bowel obstructions pathophysiology?

Answer 5

Large bowel obstruction are less common as lumen is larger so harder to block.

Question 6

Risk factors of large bowel obstruction?

Answer 6

Malignancy ( 90%)
volvulus ( twisting of bowel)
Diverticulitis
Crohns Disease

Question 7

Symptoms of large bowel obstruction?

Answer 7

Abdominal pain in lower
Abdominal distension more than SBO
Vomiting occurs later than SBO
Constipation earlier than SBO

Question 8

Investigations of large bowel obstruction?

Answer 8

Abdominal X-ray:

-Gas shadow where blockage is but doesn’t show rectum thats why a digital rectum exam is done.

-Caecum + ascending colon will be distended

Digital rectum exam ( DRE ):
-empty rectum
- hard stools
- might be blood

Question 9

Treatment for bowel obstructions?

Answer 9

Decompression of bowel
- drip + suck
- IV fluid

Fluid resuscitation

Antibiotics

Surgery

Question 10

What is Pseudo-bowel obstruction?

Answer 10

Presents identical to SBO/LBO

Occasionally the whole bowel is obstructed.

Best way to manage is by treating underlying issue.