True false questions about the removal of intestine?

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SUMMARY

This discussion centers on the physiological consequences of small intestine resections, specifically in a 60-year-old man who had 60% and then 50% of his small intestine removed due to ischaemic necrosis. Key conclusions include that megaloblastic anemia and iron deficiency anemia are likely outcomes due to impaired absorption in the terminal ileum and duodenum, respectively. Prolonged clotting time is also a probable consequence due to reduced bile salt absorption. The discussion highlights the adaptability of the jejunum and ileum, noting that while the jejunum can compensate for some functions, ileum damage cannot be compensated.

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I don't have answers for these question. I would like to clarify the answers to questions I have answered and get some with ones I don't know. Thanks :smile:

A 60 years old man had 60% of his small intestine resected due to ischaemic necrosis. If he gets no further treatment, the features he may develop are include.

a) Megaloblastic anaemia
I'm thinking this is true because terminal ileum is needed for vitamin B12 absorption. But the question is vague, 60 percent of which part of small intestine?
b) Prolonged clotting time.
True. Due to lack of absorption of bile salts from terminal ileum
c)Hyperproteinamic odema
No idea
d)Hypercalcaemia
False. Hypo due to its absorption in small intestine.
e)Iron deficiency anaemia
True due to its absorption in duodenum

A 60 year old man had 50% distal small intestine resected. If he gets no further treatment he may develop.

a)Hypercalaemia
b)Hypoproteineamic oedema
c)Dehydration

I'm not sure about the answers to these. Also I heard that duodenum and jejujunum can adapt to carry out each other's function if one is resected, but ileum damage can not be compensated. Is that correct.

Thanks :smile:
 
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sameeralord said:
I don't have answers for these question. I would like to clarify the answers to questions I have answered and get some with ones I don't know. Thanks :smile:

A 60 years old man had 60% of his small intestine resected due to ischaemic necrosis. If he gets no further treatment, the features he may develop are include.

a) Megaloblastic anaemia
I'm thinking this is true because terminal ileum is needed for vitamin B12 absorption. But the question is vague, 60 percent of which part of small intestine?
b) Prolonged clotting time.
True. Due to lack of absorption of bile salts from terminal ileum
c)Hyperproteinamic odema
No idea
d)Hypercalcaemia
False. Hypo due to its absorption in small intestine.
e)Iron deficiency anaemia
True due to its absorption in duodenum

Wow that is a really hard question. Are you sure there weren't any other parts to it?!

At 60% that could include or exclude the ileum, which would rule in or out, A.

D is wrong.

Depending on which part, E could be right or wrong.

I am going to lean with B. Here is my reasoning;

If the 60% includes the ileum, you've got reduced reabsorption of bile salts. This makes the liver work harder and lowers your pool of them. With less bile salts, there will be less fat soluble vitamins (ADEK), specifically vitamin K--Thus an increased clotting time.

Likewise, if the 60% doesn't include the ileum, then you necessarily remove lots of the jejunum which means you remove the part of the small bowel that does the fat absorption, lipid soluble vitamins (like K again) are absorbed in micelles in the jejunum. So again, we have an increased clotting time.

Both A and E could be correct answers, depending on the circumstance, but I think this is one of those "most correct" type questions and the most correct answer--Par the vagueness of the question, would be B--In my opinion.

However, there is C. Which could also be a right answer (see below). But, if you just took the proximal 2/3 of SB, I'm not sure C would apply for the reasons below.Edit to add; If you took the proximal 2/3 of the SB, you would take the jejunum too.

The ileum has most of the same transporters as the jejunum, but by time the chyme gets to the ileum most fats/carbs/AAs are already absorbed which is why it does mostly salt absorption. I suppose if you took the proximal 2/3, the ileum could (in theory) take over AA absorption and get you enough amino acids to not have hypoproteinemia. Which means C would be an incorrect answer I think.


sameeralord said:
A 60 year old man had 50% distal small intestine resected. If he gets no further treatment he may develop.

a)Hypercalaemia
b)Hypoproteineamic oedema
c)Dehydration

I'm not sure about the answers to these.

So this is a little more specific, but a tough one too!, in that we know what parts of the bowel are affected. The ileum and the jejunum. So what's on this list, that would be most affected?

The small bowel, reabsorbs the majority of your water (about 7.5L vs the large bowels 1.5L, in a healthy adult). The majority of the water absorption is done in the terminal small bowel (following the movement of salt in the ileum).

BUT, the colon can make up for lots of missed water absorption by the SB--As seen in diseases where the SB secretes too much water. And without lots of the SB there to begin with, you would have reduced secretion of water in the first place. So while dehydration looks appealing, I don't think it is correct.

A., I don't believe has much to do with the question. Most calcium absorption is done in the SB (about 90%) and of that, I believe about 90% is done in the duodenum.

That leaves B as the only other option. I'm not 100% for the science behind it. My guess would be 2 causes.

1; the reduction in bile salt absorption means the liver the stays in "bile salt production"-mode, as the gallbladder wouldn't fill up and the livers production of serum proteins would go down. Leading to hypoproteinemia

2; the jejunum absorbs the majority of your carbs, lipids and amino acids. With 50% of the distal SB removed, you'd have reduced amino acid absorption and a reduction in the production of serum proteins by the liver--Again, leading to hypoproteinemia.

Edit. There would still be a little Jejunum remaining with 50% removal of the distal SB. Though, I think this would not be enough to do full amino acid absorption, making 2 still apply here.

I think B, would be the best answer here as well.

Edit again. I suppose it comes down to how much water your source says the colon is capable of absorbing. Different sources list different amounts, in my GI physio stuff we learned it is capable of pulling in up to 4.4 L. Which would mean you'd probably get dehydrated in this example. A quick look through Google has some sources saying the colon is capable of pulling in up to 6.4 L, which could cover what was lost in the removal of the last half of the SB--So no dehydration.
 
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