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c/reconstitution·submitted 5 months ago by u/mateusz_achebe

[Discussion] units are doing more work than we give it credit for

Discussionbranch of 12 comments

The title is the argument: units are doing more work than we give it credit for. Here is the rest of it. Started reconstituting everything to a round concentration and the six-in-the-morning error rate went to zero. The dead space question sent me down a rabbit hole for a week. It is a fraction of a unit and it is…

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12 comments, started 5 months ago
u/rosa_mensah101 points·5 months ago

I keep a laminated card in the drawer with the arithmetic on it. Looks ridiculous. Has never once let me draw the wrong volume.

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u/swirl_dont_shakereconstitution64 points·5 months ago

That is sterile water, not bacteriostatic. Same appearance, different product, and it matters for a multi-draw vial.

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u/erez_perrin23 points·5 months ago

a U-100 syringe reads 100 units to the millilitre, every time

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u/britta_nakamura147 points·5 months ago

more water is not more drug, it is the same drug in a bigger volume

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u/anjali_tamm111 points·5 months ago

Adding more water does not change how much peptide is in the vial. It changes the concentration, which changes the volume you draw for the same amount. That is the entire relationship.

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u/honest_syringe_202540 points·5 months ago

bacteriostatic water has the preservative, sterile water does not

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u/saskia_rahimi90 points·5 months ago

label the vial with the date as well as the concentration

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u/runa_cabrera76 points·5 months ago·edited

Small fix — a U-100 syringe is 100 units per mL. If yours is marked differently it is not U-100 and the whole calculation changes.

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u/zaid_balogun28 points·5 months ago

reconstituting at a round concentration makes every later dose easy

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u/priya_guerrero66 points·5 months ago·edited

What concentration did you actually reconstitute at, rather than what did you intend to?

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u/marisol_frisk16 points·5 months ago

20mg into 1mL is 20mg/mL, and 5mg of that is 25 units

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u/sigrid_kaufmann7 points·5 months ago

dead space in the needle hub is real and it is small

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About c/reconstitution

The arithmetic and the technique. Bacteriostatic versus sterile water, reconstitution volume as a concentration choice, converting mg/mL into insulin-syringe units, dead space, swirl-not-shake, stopper coring, and how long a reconstituted vial is actually good for. Math errors get corrected fast and politely.

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