How to represent IV ingredients when solvent is unknown?


#1

I’m looking for advice on how to represent the amounts of IV ingredients when we don’t know which ingredient is the solvent. I know the usual way (per the spec for Medication.ingredient.amount) is a ratio of active ingredient over volume of solvent, e.g. 2g/50ml.

But in our system we just store a list of components with no indication of which one is the solvent. Do we have any options here? I had thought of using “1 bag” as the ratio denominator for every component, but I don’t know if that’s acceptable…

Thank you for reading!


#2

I think our implementation uses a generic denominator of 1 each when bag volume is not known.

FYI - I had logged a prior change request asking for the choice of SimpleQuantity | Ratio for ingredient.amount, but the resolution was to use a denominator, such as “1 tab”. I believe Pharmacy updated the examples, such as http://hl7.org/fhir/STU3/medicationexample0311.xml.html, to reflect that is ok (for an oral medication example).


#3

Ok, so there is a precedent for using generic denominators. Thank you for the response, I think this is the answer to our problem!