Ischaemia of the Small Bowel

Question 1

usually ___ but can be ___

Answer 1

acute, chronic

Question 2

what are the two groups of causes

Answer 2

• mesenteric arterial occlusion

- non-occlusive perfusion insufficiency - less common

Question 3

what are the two causes of mesenteric arterial occlusion?

Answer 3

1- mesenteric artery atherosclerosis

2- thromboembolism from the heart (a.fib)

Question 4

what is the most common cause of acute ischaemia ?

Answer 4

thromboembolism from heart

Question 5

what are the 4 causes of non-occlusive perfusion insufficiency

Answer 5

1. shock
2. strangulation obstructing venous return
3. drugs
4. hyperviscosity

Question 6

why does shock often cause ischaemia in the bowel ?

Answer 6

The body tries to preserve blood flow to more important areas when blood is lost and BP is low

Question 7

give some examples of strangulation?

Answer 7

hernia

adhesion - common

Question 8

which drugs can cause perfusion insufficiency ?

Answer 8

cocaine

Question 9

cause in acute : from most common to least _____> _______> Non occlusive vascular disease

Answer 9

thromboembolism > in situ thrombus formation > non-occlusive vascular disease

Question 10

The ____ is the most metabolically active part of the bowel wall and therefore the most sensitive to the effects of ____ so they are most prominently affected

Answer 10

The mucosa is the most metabolically active part of the bowel wall and therefore the most sensitive to the effects of hypoxia so they are most prominently affected

Question 11

The longer the period of hypoxia the greater the -___of the damage to the bowel wall and the greater the likelihood of _____

Answer 11

The longer the period of hypoxia the greater the depth of the damage to the bowel wall and the greater the likelihood of complications

Question 12

In non occlusive ischaemia much of the tissue damage occurs after ______

Answer 12

reperfusion

Question 13

what is the outcome if the ischaemia is confined to the mucosa?

Answer 13

outcome of complete regeneration is possible and mucosal integrity is restored

Question 14

what is the outcome if the ischaemia is submucosal (mural infarction) ?

Answer 14

can lead to a fibrous stricture

Question 15

what is the outcome if the ischaemia is transmural (gangrene) ?

Answer 15

will lead to perforation if not surgically resected. Even before perforation, septicaemia may ensure

Question 16

what does ischaemia look like histologically?

Answer 16

get an outpouring of fibrin

Question 17

with a fibrous stricture you can develop _____ _____

Answer 17

chronic ischaemia

Question 18

what are the first tests to order?

Answer 18

FBC
Chemistry panel
ABG/ lactate 
FBC
AXR
CT angiogram

Question 19

what may ABGs show?

Answer 19

acidosis

Question 20

lactate level elevated?

Answer 20

yes

Question 21

crp levels may be ___

Answer 21

normal

Question 22

WCC levels may be

Answer 22

up a little

Question 23

should intervene ___

Answer 23

quickly

Question 24

what are the management ooptions

Answer 24

• resect if non viable

- re-anastomose or stable and planned return