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Old 07-26-2014
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Default Q about Small bowel obstruction

Why do we see Metabolic Acidosis with Bowel obstruction?
Any explanation? Thanks.
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Old 07-27-2014
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i would assume the main presentation in small bowel obstruction would be alkalosis, due to severe vomiting.

however lactic acidosis is possible if the obstruction is severe enough to compromise the blood supply to the small bowel, or if there is an overall loss in fluids, causing hypovolemia and hypofusion ( severe cases i assume)....

lastly, the small bowel receives a rich supply of bicarbonate, and if this is lost, sue to the obstruction, it may cause acidosis.. ( not sure about this thought). These are the only ways I can see acidosis being prevalent.

Last edited by USMLEgen; 07-27-2014 at 06:11 AM.
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Old 07-28-2014
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Quote:
Originally Posted by USMLEgen View Post
i would assume the main presentation in small bowel obstruction would be alkalosis, due to severe vomiting.

however lactic acidosis is possible if the obstruction is severe enough to compromise the blood supply to the small bowel, or if there is an overall loss in fluids, causing hypovolemia and hypofusion ( severe cases i assume)...
Can you tell me please why there would be Acidosis in hypovolemia? What's the mechanism?
Thank you very much
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Old 07-30-2014
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Another question please,

Any explanation why there is increased renal calcium excretion (hypercalciuria) and thus increased risk of kidney stones in Metabolic Acidosis ?
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Old 07-30-2014
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In metabolic acidosis i-e increased H+ion concentration replaces calcium from albumin, leading to increased Ionized calcium in the serum (hypercalcemia)--->hypercalciuria-->stones.


this is my understanding. please someone Correct me If I am wrong.



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Another question please,

Any explanation why there is increased renal calcium excretion (hypercalciuria) and thus increased risk of kidney stones in Metabolic Acidosis ?
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Old 07-30-2014
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it depends upon the location of obstruction. if the obstruction is in proximal bowel, this will lead to metabolic acidosis due to loss of gastric hydrochloric acid (vomiting). but is the obstruction is in distal portion of small intestine, then loss of intestinal alkaline fluids will result in metabolic acidosis.

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Why do we see Metabolic Acidosis with Bowel obstruction?
Any explanation? Thanks.
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Old 07-30-2014
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inRace, from my understanding, with vomitting, you will have metabolic ALKALOSIS (loss of HCl)...also, with hypovolemia, would lead to decreased perfusion and lactic acid build up (i read this in a paper), hence metabolic acidosis..
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Old 07-31-2014
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Quote:
Originally Posted by InRace View Post
it depends upon the location of obstruction. if the obstruction is in proximal bowel, this will lead to metabolic acidosis due to loss of gastric hydrochloric acid (vomiting). but is the obstruction is in distal portion of small intestine, then loss of intestinal alkaline fluids will result in metabolic acidosis.
Great! Except as USMLEgen said: proximal obstruction would cause metabolic ALKALOSIS.

Thank u so much USMLEgen & InRace.
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Yes, Metabolic alkalosis is right. thanks for correction.
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Old 07-31-2014
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GL guys ! almost there I'm sure
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