how long a vial lasts is easy math and mostly the wrong number

InventoryManagerSenior Analyst

The math is trivial: total mass / mass per draw = number of draws. 10mg vial, 500mcg per draw, 20 draws.

Where it stops being useful: that assumes the limiting factor is running out, and usually it isn't. The beyond-use clock after reconstitution frequently expires before the vial does.

So the practically relevant number is whichever comes first, draws remaining or time since reconstitution. And the second one is the one people don't track.

This is the calc I'd most like the app to do for me, because it needs two facts that live in different places: the concentration and the reconstitution date.

6 replies5 upvotesTracking & Calculator

6 replies

  • cold_chainSenior Analyst

    And the two interact. Going more concentrated to make a vial last only helps if the time limit isn't binding first. Otherwise you've made your draws harder to measure for nothing.

    4 upvotes

    • InventoryManagerSenior Analyst

      Neat way to put it. Longevity is pointless if time binds first.

      2 upvotes

  • newvialwhodisSenior Analyst

    whats beyond use again?

    2 upvotes

  • same_tbhSenior Analyst

    time runs out before the vial does. yep

    2 upvotes

  • quick_qSenior Analyst

    20 draws is a lot for one vial isnt it?

    1 upvote

  • LabelYourVialsSenior Analyst

    Which brings it back to writing the date on the vial.

    3 upvotes

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