Bowel Obstruction Flashcards
what causes the bowel proximal to obstruction to become dilated?
air and fluid
what is disrupted in bowel obstruction?
peristalsis
what determines how early vomiting develops in obstruction?
how proximal the obstruction is
why can vomiting occur in obstruction if nothing is eaten?
GI secretions are continually produced and can be vomited
what type of obstruction does vomiting semi-digested food with no bile suggest?
gastric outlet obstruction
what type of obstruction does bile stained vomit suggest?
upper small bowel obstruction
what type of obstruction does thicker, brown and foul smelling vomit suggest?
a more distal obstruction (distal small bowel, large bowel)
name the four main symptoms of intestinal obstruction
vomiting
pain
constipation
distension
what causes pain in bowel obstruction?
distension of the bowel
describe the pain that presents with bowel obstruction
intermittent episodes of colicky pain
what type of constipation is associated with bowel obstruction?
absolute constipation
what does absolute constipation mean?
neither faces or flatus is passed rectally
what type of obstruction causes more gradual onset of symptoms and why?
large bowel obstruction
due to its large capacity and ability to absorb
what is incomplete obstruction?
when the bowel is only partially obstructed
what does chronic incomplete obstruction result in?
gradual hypertrophy of the muscle of the bowel wall proximal to the obstruction
what does obstruction with abdominal tenderness indicate?
bowel strangulation
in normal bowel obstruction, what is lacking on examination?
abdominal tenderness
what may be able to feel on palpation in bowel obstruction?
the obstructive mass
what is heard upon abdominal percussion in bowel obstruction?
the centre of the abdomen tends to be resonant due to gaseous distension
why does the groin need to be examined in bowel obstruction?
for an obstructing hernia
what do bowel sounds sound like in bowel obstruction?
high-pitched and tinkling
what is the most useful first line investigation for bowel obstruction?
supine AXR
what scan can be used to confirm diagnosis of bowel obstruction and look for its cause?
CT scan
what diet should a patient with bowel obstruction be on?
nil by mouth
what is involved in the initial management of intestinal obstruction?
IV cannula and send blood
IV fluids
NG tube
why is an NG tube inserted in intestinal obstruction?
to decompress the stomach
name seven mechanical things that can cause bowel obstruction
adhesions incarcerated hernia volvulus tumour strictures bolus obstruction intussusception
name three things that can cause adhesions
congenital
abdominal surgery
peritonitis
what is a volvulus?
a mobile loop of the bowel rotating around itself, causing obstruction
what two diseases can cause inflammatory strictures?
crohn’s
diverticular disease
what are obstructions caused by strictures typically like?
incomplete
what happens in intussusception?
a segment of bowel wall becomes telescoped into the segment distal to it
what is paralytic ileus?
disruption of the normal propulsive activity of the GI tract due to failure of peristalsis
name three risk factors for paralytic ileus
recent GI surgery
inflammation
diabetic ketoacidosis
how is paralytic ileus treated?
“drip and suck” while waiting for restoration of peristalsis
what is pseudo-obstruction?
acute dilation of the colon in the absence of colonic obstruction in acutely unwell patients
