hanadr
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I'm still reeling from being told by a doctor that 5% dextrose drip is good for a dehydrated diabetic: on the grounds it's "only water".
so I did my sums.
i] One mole of glucose weighs 180grams.
ii] One millimole of glucose weighs 0.18grams
iii] the total blood volume of an adult human is about 5 litres usually a bit less [depending on body mass.]
iv] multiplying up: the total amount of glucose circulating in the body when bg is 5mmol/l is about 5 x 0.18 x 5 = 4.5grams.
v] 1 litre contains 10 x 100 ml of solution
vi] 1% solution contains 1 gram solute [glucose?] per 100ml solution.
vii] 1 litre 1% solution contains 10 grams solute
viii] 1litre 5% solution contains 50g solute.
ergo
ix] 1litre 5% glucose solution drip delivers 50 grams of glucose to a person who can't process it and should have about 5 grams glucose in total blood volume.
Why 5% solution?
If the liquid that blood cells are in has a very different osmotic potential from the cell contents, the cells will either burst or shrivel. Remember demonstrations of osmosis at school? potato chips in different concentrations of salt solution?[plant cells don't burst, animal cells do]
5% dextrose has a similar osmotic potential to normal cell contents. Pure water would burst blood cells and a more concentrated glucose solution would shrivel them.
People who are not diabetic, would rapidly transport the excess glucose into cells. Diabetics CANNOT.
Heavens preserve me from doctors who don't remember year 10 chemistry.
Hana
so I did my sums.
i] One mole of glucose weighs 180grams.
ii] One millimole of glucose weighs 0.18grams
iii] the total blood volume of an adult human is about 5 litres usually a bit less [depending on body mass.]
iv] multiplying up: the total amount of glucose circulating in the body when bg is 5mmol/l is about 5 x 0.18 x 5 = 4.5grams.
v] 1 litre contains 10 x 100 ml of solution
vi] 1% solution contains 1 gram solute [glucose?] per 100ml solution.
vii] 1 litre 1% solution contains 10 grams solute
viii] 1litre 5% solution contains 50g solute.
ergo
ix] 1litre 5% glucose solution drip delivers 50 grams of glucose to a person who can't process it and should have about 5 grams glucose in total blood volume.
Why 5% solution?
If the liquid that blood cells are in has a very different osmotic potential from the cell contents, the cells will either burst or shrivel. Remember demonstrations of osmosis at school? potato chips in different concentrations of salt solution?[plant cells don't burst, animal cells do]
5% dextrose has a similar osmotic potential to normal cell contents. Pure water would burst blood cells and a more concentrated glucose solution would shrivel them.
People who are not diabetic, would rapidly transport the excess glucose into cells. Diabetics CANNOT.
Heavens preserve me from doctors who don't remember year 10 chemistry.
Hana
