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Old 07-12-2011
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Question question on electrolye metabolism

A 50 year old man weighs 70 kg, on a fixed NaCl intake 200mmol/day, is given injection of powerful mineral corticosteroid daily for 4 days. He has free access to water during these 4 days. Daily NaCl excretion is bellow:

day 1, 30 mmol
day 2, 90 mmol
day 3, 180 mmol
day 4, 200 mmol
assuming 150 mmol is 1 Kg in weight, what is his weight by the end of day 4
1, 60 kg
2, 74 kg
3, 75 kg
4, 72 kg
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Old 07-12-2011
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Quote:
Originally Posted by usluipek View Post
A 50 year old man weighs 70 kg, on a fixed NaCl intake 200mmol/day, is given injection of powerful mineral corticosteroid daily for 4 days. He has free access to water during these 4 days. Daily NaCl excretion is bellow:

day 1, 30 mmol
day 2, 90 mmol
day 3, 180 mmol
day 4, 200 mmol
assuming 150 mmol is 1 Kg in weight, what is his weight by the end of day 4
1, 60 kg
2, 74 kg
3, 75 kg
4, 72 kg

the ans is 72 kg the key is to see hw mch has been absorbed in body by subtracting from the amount xcreted by day 4 no absorption has occured n in the last three days person has absorbed 300mmol NaCl n this is equal to 2 kg hence the wt is 72
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Old 07-13-2011
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good question..,is it 4.)72kg
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Old 07-13-2011
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Can someone explain how "injection of mineralcortisone" impact the Na metabolism, how are we supposed to use this information in this question?
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Old 07-13-2011
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Quote:
Originally Posted by usluipek View Post
Can someone explain how "injection of mineralcortisone" impact the Na metabolism, how are we supposed to use this information in this question?
A mineral corticosteroid would mean mineralocorticoid ... which is Aldosterone!
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Hope2 pass, We all know mineralcorticoid is aldosterone. what I was asking is how we use this information, does the aldosterone injection affects the answer or it is just a smoking gun?
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Quote:
Originally Posted by usluipek View Post
Hope2 pass, We all know mineralcorticoid is aldosterone. what I was asking is how we use this information, does the aldosterone injection affects the answer or it is just a smoking gun?
Oh ok, Well its just a distractor coz you dont need to use that information to answer the question! All we need is the amount of intake & excretion of Na.

Intake Excreted Reabsorbed
Day 1 - 200 30 170
Day 2 - 200 90 110
Day 3 - 200 180 20
Day 4 - 200 200 0


Total reabsorbed in 4 days = 300 mmol
Since 150 mmol = 1 Kg, the pt gained a total of 2 Kg, therefore Ans = 72 Kg.
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