Bowel Obstruction

Question 1

what causes the bowel proximal to obstruction to become dilated?

Answer 1

air and fluid

Question 2

what is disrupted in bowel obstruction?

Answer 2

peristalsis

Question 3

what determines how early vomiting develops in obstruction?

Answer 3

how proximal the obstruction is

Question 4

why can vomiting occur in obstruction if nothing is eaten?

Answer 4

GI secretions are continually produced and can be vomited

Question 5

what type of obstruction does vomiting semi-digested food with no bile suggest?

Answer 5

gastric outlet obstruction

Question 6

what type of obstruction does bile stained vomit suggest?

Answer 6

upper small bowel obstruction

Question 7

what type of obstruction does thicker, brown and foul smelling vomit suggest?

Answer 7

a more distal obstruction (distal small bowel, large bowel)

Question 8

name the four main symptoms of intestinal obstruction

Answer 8

vomiting
pain
constipation
distension

Question 9

what causes pain in bowel obstruction?

Answer 9

distension of the bowel

Question 10

describe the pain that presents with bowel obstruction

Answer 10

intermittent episodes of colicky pain

Question 11

what type of constipation is associated with bowel obstruction?

Answer 11

absolute constipation

Question 12

what does absolute constipation mean?

Answer 12

neither faces or flatus is passed rectally

Question 13

what type of obstruction causes more gradual onset of symptoms and why?

Answer 13

large bowel obstruction

due to its large capacity and ability to absorb

Question 14

what is incomplete obstruction?

Answer 14

when the bowel is only partially obstructed

Question 15

what does chronic incomplete obstruction result in?

Answer 15

gradual hypertrophy of the muscle of the bowel wall proximal to the obstruction

Question 16

what does obstruction with abdominal tenderness indicate?

Answer 16

bowel strangulation

Question 17

in normal bowel obstruction, what is lacking on examination?

Answer 17

abdominal tenderness

Question 18

what may be able to feel on palpation in bowel obstruction?

Answer 18

the obstructive mass

Question 19

what is heard upon abdominal percussion in bowel obstruction?

Answer 19

the centre of the abdomen tends to be resonant due to gaseous distension

Question 20

why does the groin need to be examined in bowel obstruction?

Answer 20

for an obstructing hernia

Question 21

what do bowel sounds sound like in bowel obstruction?

Answer 21

high-pitched and tinkling

Question 22

what is the most useful first line investigation for bowel obstruction?

Answer 22

supine AXR

Question 23

what scan can be used to confirm diagnosis of bowel obstruction and look for its cause?

Answer 23

CT scan

Question 24

what diet should a patient with bowel obstruction be on?

Answer 24

nil by mouth

Question 25

what is involved in the initial management of intestinal obstruction?

Answer 25

IV cannula and send blood
IV fluids
NG tube

Question 26

why is an NG tube inserted in intestinal obstruction?

Answer 26

to decompress the stomach

Question 27

name seven mechanical things that can cause bowel obstruction

Answer 27

adhesions 
incarcerated hernia 
volvulus 
tumour
strictures 
bolus obstruction 
intussusception

Question 28

name three things that can cause adhesions

Answer 28

congenital
abdominal surgery
peritonitis

Question 29

what is a volvulus?

Answer 29

a mobile loop of the bowel rotating around itself, causing obstruction

Question 30

what two diseases can cause inflammatory strictures?

Answer 30

crohn’s

diverticular disease

Question 31

what are obstructions caused by strictures typically like?

Answer 31

incomplete

Question 32

what happens in intussusception?

Answer 32

a segment of bowel wall becomes telescoped into the segment distal to it

Question 33

what is paralytic ileus?

Answer 33

disruption of the normal propulsive activity of the GI tract due to failure of peristalsis

Question 34

name three risk factors for paralytic ileus

Answer 34

recent GI surgery
inflammation
diabetic ketoacidosis

Question 35

how is paralytic ileus treated?

Answer 35

“drip and suck” while waiting for restoration of peristalsis

Question 36

what is pseudo-obstruction?

Answer 36

acute dilation of the colon in the absence of colonic obstruction in acutely unwell patients