Disease of the Small Intestine

Question 1

what is mesenteric ischaemia?

Answer 1

ischaemia of the mesenteric artery restricting blood flow to SI

Question 2

what causes mesenteric ischaemia?

Answer 2

arterial occlusion e.g. atherosclerosis, non-occlusive perfusion insufficiency (shock, strangulation, obstructed venous return e.g. hernia)

Question 3

types of mesenteric ischaemia…

Answer 3

chronic, acute

Question 4

what is chronic mesenteric ischaemia

Answer 4

usually superior MA and presents with abdominal cramps

Question 5

where does acute mesenteric ischaemia affect the most?

Answer 5

small bowel usually infarcted but colon survives

Question 6

what is the pathogenesis of small bowel ischaemia due to Mesenteric ischaemia?

Answer 6

hypoxia of mucosa > mural infarct > transmural infarct > gangrene > perforation > sepsis

Question 7

common complications of mesenteric ischaemia?

Answer 7

fibrosis, stricture, chronic ischaemia, gangrene, perforation & sepsis

Question 8

presentation of SB ischaemia?

Answer 8

severe, poorly localised pain
shock
inc amylase

Question 9

colon ischaemia presentation?

Answer 9

left sided pain, CVD, shock, vasculitis

Question 10

why should you be weary of mesenteric ischaemia?

Answer 10

may be hard diagnosis - no signs on X-ray. note if pt is taking high dose of analgesia

Question 11

ix for mesenteric ischaemia?

Answer 11

CT angiography, bloods (lactate & amylase ^), endoscopy

Question 12

tx for mesenteric ischaemia?

Answer 12

resect, re-anastomose, embolectomy of sup. mesenteric artery

Question 13

bowel obstruction is described as?

Answer 13

peristalsis is disrupted and dilation of bowel proximal to obstruction

Question 14

types of bowel ob pointers?

Answer 14

upper ie. small bowel: acute epigastric pain, hours of onset, vomit

large bowel: more gradual, colicky abdominal pain, distension, vomit

Question 15

true/false…

upper GI obstruction more likely to have faeculent vomit

Answer 15

false…

lower GI obstruction more likely to have faeculent vomit

Question 16

pathophysiology of bowel obstruction?

Answer 16

fluid, gas > arterial & venous blockage > ischaemia > perforation > sepsis

Question 17

what are the 4 aetiological factors of bowel obstruction and an example for each?

Answer 17

within lumen- gall stones, bezoar
within wall- tumour, crohn’s
outside wall- adhesions, hernia, intussusception
arterial: atherosclerosis

Question 18

symptoms of bowel obstruction?

Answer 18

colicky pain, absolute constipation, vomit, burping, abdominal distension, no bowel sounds

Question 19

describe vomit associated with bowel obstruction?

Answer 19

proximal= earlier and semi digested food with little bile
distal= opposite & faeculent

Question 20

signs of bowel obstruction?

Answer 20

abdominal distension, visible peristalsis, lack of tenderness, mass may be palpable, hyperressonant, check for hernias,

Question 21

ix to see state of patient?

Answer 21

urinalysis, bloods

Question 22

diagnosis of bowel obstruction

Answer 22

supine AXR, contrast CT abdomen

Question 23

tx for bowel ob?

Answer 23

ABC, analgesia, fluids & K, NG tube drainage, anti-thromboembolic measures

Question 24

what is tx for bowel ob after 72 hrs of medical tx?

Answer 24

surgical tx…

laparotomy & antibis

Question 25

what antibiotics are given for bowel ob?

Answer 25

gent & metronidazole

Question 26

why are fluid with K given?

Answer 26

pt is usually hypokalaemic and alkalotic

Question 27

what should be noted about the admin for all medication in bowel ob?

Answer 27

must all be given IV

Question 28

what are 2 main conditions can result from bowel ob?

Answer 28

adynamic bowel obstruction & strangulation w perforation

Question 29

what are 2 types of dynamic bowel obstructions?

Answer 29

paralytic ileus and oglivies syndrome?

Question 30

what is a paralytic ileus, symptoms and tx?

Answer 30

failure of peristalsis (due to surgery, diabetic keto acidosis, peritonitis) s/s: similar to bowel ob tx: drip & suck

Question 31

what is Ogilvie's syndrome, causes and ix?

Answer 31

acute dilation of colon (w/o obstruction) in acutely unwell pts causes: coronary artery bypass grafts, pneumonia etc ix: ACR & CT Tx: colonic decompression

Question 32

explain strangulation as a complication of bowel ob?

Answer 32

proportion of bowel becomes trapped so venous return obstructed - may progress to infarct / perforation - pain, sepsis, shock - tx: surgery

Question 33

how to check for perforation?

Answer 33

s/s: generalised peritonism | ix: erect CXR, CT

Question 34

what is coeliac disease?

Answer 34

autoimmune inflammation of mucosa in response to gluten

Question 35

hypersensitivity to ___ mediated by T cells that are found in intraepithelial lymphocytes (IELs) cause Coeliac's

Answer 35

gliadin

Question 36

pathophysiology of coeliacs?

Answer 36

less enterocytes due to IEL damage > loss of villous structures > loss of surface area> reduction in absorption and a flat duodenal mucosa

Question 37

what is coeliac's associated with?

Answer 37

dermatitis herpertiformis and childhood diabetes (T1)

Question 38

histological findings of coeliacs?

Answer 38

villus atrophy & crypt hypertrophy

Question 39

ix for coeliac?

Answer 39

duodenal endoscopy & biopsy*, serology (anti-TTG antibody)

Question 40

s/s of coeliac?

Answer 40

non specific (wt loss, bloating, failure to thrive etc)

Question 41

tx of coeliac disease?

Answer 41

gluten free diet, vitamin supplements

Question 42

complications of coeliacs?

Answer 42

t-cell lymphomas, small bowel carcinoma, gall stones common, ulcerative-jejenoilleitis

Question 43

3 microscopic signs of ulcerative-jejenoilleitis ?

Answer 43

fibrinopurulent debris, base of inflamed granulation tissue, fibrotic scar tissue

Question 44

complications of ulcerative-jejenoilleitis?

Answer 44

perforation, haemorrhage, stenosis, gastric metaplasia > H.Pylori

Question 45

what is intestinal failure?

Answer 45

inability to maintain adequate nutrition/ fluid stats via intestines

Question 46

classes of intestinal failure?

Answer 46

- acute - T1 - T2 - T3

Question 47

type 1 intestinal failure description?

Answer 47

self-limiting s: vomiting, dysphagia, diarrhoea A: pancreatitis, obstruction T: replace fluids, parenteral nutrition, PPIs

Question 48

T2 intestinal failure description...

Answer 48

prolonged PN support needed (weeks, months) A: sepsis, crohn's, SMA, radiation, adhesions, fistulas T: PN & enteral feeding

Question 49

T3 intestinal failure description...

Answer 49

chronic A: small bowel syndrome, crohn's & SBS, dysmotility, malabsorption T: home PN, transplant, glucagon-like-peptide2

Question 50

when would you consider transplant for intestinal failure?

Answer 50

T3 intestinal failure with liver disease

Question 51

ix for intestinal failure?

Answer 51

bloods (dec albumin), dec vitamins & zinc

Question 52

most common aetiology for intestinal failure?

Answer 52

ischaemia, malabsorption, SBS

Question 53

what is SBS?

Answer 53

<50cm of bowel | due to frequent resections (e.g. Crohn's/infarct)

Question 54

in non-occlusive ischamia most damage is as a result of...

Answer 54

tissue reperfusion