For more than 50 years medical laboratories have recorded concentration
values as 'mg/dL' or 'mEq/L' but are now changing over to 'mmol/L or mol/L'
standard SI units. I believe that mEq/L = mmol/L since 'one equivalent =
one mole' but is there any simple way of converting a serum cholesterol
value of 150mg/dL to mmol/L? Does one have to compute the 'gram molecular
weight of cholesterol' or is that figure listed somewhere?
"John L. Shamblin, Jr." <[Only registered users see links. ]> wrote in message
news:[Only registered users see links. ]...
The simplest way is to find a table of conversion factors. Otherwise, you
have to know the molar weight, but you can look it up - e.g., in the Merck
Most physicians forget that they ever took chemistry. All they really have
know is how the lab results compare with the reference range for healthy
people, and it is common for the result reports to include that information.
The first high-volume clinical chemistry analyzers were the Technicon SMA
series. The output was drawn as a bar graph by a strip-chart recorder. The
charts were pre-printed with gray areas for the reference range (then called
normal ranges) of each analyte, so that the physician could see at a glance
if any of the results needed attention. The output came to be called a
profile, and "profiling" became a common term in medicine.
When I went to work at Technicon (1970), each hospital had its own normal
ranges, and they were different even between nearby hospitals that served
similar populations. Better quality control has now corrected that.
"John L. Shamblin, Jr." <[Only registered users see links. ]> wrote in message news:<[Only registered users see links. ]>...
Not entirely true i am afraid, John.
1 equivalent is only 1 mol when the molecule is monofunctional in
relation to the quantified property. For example sulfuric acid is
bifunctional when it comes to acid-base reactions, so 1 equivalent is
KMnO4 can be pentafunctional or trifunctional in redox reactions
depending on the products formed (Mn2+ or MnO2). Here 1 equivalent
would either be 0.2 or 0.333 mol.
And going for SI units in the mg/dL case.. there is no need to go to
mols here... the SI units here are kg and L so basically the old
result is multiplied by 10E-5 (mg -> kg: 10E-6 and dL -> L: 10E-1 =>
10E-6/10E-1 = 10E-5)