wk 8 7 bowel obstruction

Question 1

outline the pathophysiology of bowel obstruction

Answer 1

(any part in GI)
dilation of bowel proximal (air +fluid)
peristalsis disrupted

Question 2

t/f upper small bowel obstruction would cause large volumes of vomiting

Answer 2

true

Question 3

in distal small bowel/ large bowel obstruction what 2 things would be observed

Answer 3

colicky ab pain and distension

vomiting (possibly faeculent)

Question 4

5 associated symptoms of intestinal obstruction

Answer 4

vomiting
pain
constipation 
distension 
complete/incomplete obstruction

Question 5

t/f the more distal the obstruction, the earlier vomiting develops

Answer 5

false

more proximal = early whitey

Question 6

t/f vomiting can occur even if nil by mouth

Answer 6

true

saliva/gastric/pancreatic/bile/small intestine secretions still produced

Question 7

nature of vomit can be described as semi-digested, copious bile-stained or thicker brown vomit, what does each signify

Answer 7

semi-digested - no bile, suggests gastric outlet obstruction
copious bile stained- upper small bowel obstruction
thicker/brown - faeculuent, more distal obstruction

Question 8

how does colicky pain arise from intestinal obstructio n

Answer 8

peristalsis attempts to overcome obstruction

Question 9

t/f large bowel obstructions develop more gradually

Answer 9

true

larger capacity and absorptive activity

Question 10

in large bowel obstruction, explain what happens to the caecum

Answer 10

if ileo-caecal valve competent, backwards flow prevented, instead caecum distes with swallowed air and eventually may rupture

Question 11

what happens if the ileo-caecal valve is incompetent in large bowel obstruction

Answer 11

small bowel also distends, delaying symptoms

Question 12

in incomplete obstruction, describe the vomiting and bowel habit

Answer 12

vomiting intermittent

bowel habit - erratic / just farts

Question 13

t/f chronic incomplete obstruction leads to hyperplasia of muscle of proximal bowel wall

Answer 13

false

hypertrophy!

Question 14

peristalstic activity proximal or distal of the hypertrophic muscle is the cause of colicky pain?

Answer 14

proximal

Question 15

4 physical signs of intestinal obstruction

Answer 15

dehydration
ab distensioin
visible peristalsis
lack of ab tenderness

Question 16

obstruction with abdominal tenderness may indicate

Answer 16

strangulation

Question 17

what would the percussion of an ab obstruction be describedas

Answer 17

resonant in centre- build up of gases

Question 18

other than stomach, what else must be examined in intestinal obstruction

Answer 18

groins - hernia

Question 19

first line investigation for suspected bowel obstruction

Answer 19

supine ab x-ray

Question 20

distended small bowel loops on x-ray tend to

Answer 20

lie in a central position and have valvulae coniventes (keckring folds - mucosa)

Question 21

why arents erect ab-x-rays no longer part of routine practice

Answer 21

multiple air fluid levels

Question 22

how can a distended large bowel be classified on AXR

Answer 22

tends to lie in anatomical positon

haustra colii

Question 23

t/f CT are always used in small bowel obstruction

Answer 23

true

to confirm diagnosis and look for cause

Question 24

what would be expected to find in a CT scan of small bowel obstructi

Answer 24

promixal to obstruction - distension

distal to obstruction - collapse

Question 25

initial management of intestinal obstruction 4

Answer 25

nil by mouth
insert IV cannula and send blood
resuscitate with IV fluids (replace electrolyte loss)
NG tube - decompresses stomach

Question 26

8 mechanical causes of bowel obstruction

Answer 26

adhesions/bands
incarcerated ab wall hernia 
internal hernia 
volvulus 
tumour
inflammatory strictures
bolus obstruction #
intussusception (sml bowel folds in on inteslf)

Question 27

6 places a hernia could occur in abdomen

Answer 27

inguinal 
femoral 
umbilical 
paraumbilical 
ventral 
incisional

Question 28

2 diseases causing strictures

Answer 28

crohns
diverticulars disease
(usually incomplete obstruction)

Question 29

trichobezoar is a mass found in GI from digested

Answer 29

hair

Question 30

how is intussusception caused

Answer 30

initiated by a mass in bowel wall - lymphatic tissue or tumour, segment of bowel wall becomes telescoped into distal segment
common in children

Question 31

how does strangulation lead to infarction and perforation

Answer 31

segment of bowel becomes trapped
venous return obstructed, rising intra-vascular pressure, arterial inflow compromised
if not relieved lack of blood flow leads to infarction and perforation

Question 32

pain over a hernia suggests

Answer 32

strangulation

Question 33

other than hernias, when can strangulation occur

Answer 33

volvulus

Question 34

paralytic ileus can cause bowel obstruction, due to disruption of peristalsis, give 3 risk factors

Answer 34

recent GI surgery
inflammation with peritonitis
diabetic keto acidosis

Question 35

t/f high pitched bowel sounds are more common in paralytic ileus

Answer 35

false - peristalsis is stopped why would there be bowel sounds
pain also less common

Question 36

treatment of paralytic ileus

Answer 36

drip and suck while waiting for restoration of peristalsis

Question 37

pseudo-obstruction (Ogilvies syndrome) is

Answer 37

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

Question 38

5 associations of Ogilvies syndrome

Answer 38

hip replacement surgery 
Coronary artery bypass grafts
spinal 
pneumonia
frail/elderly patients

Question 39

when woudl colon require colonoscopic decompression in pseudo-obstruction

Answer 39

if distension is causing pain or resp compromise

Question 40

which artery is used for coronary artery bypass graft

Answer 40

mammary artery from chest wall