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c/reconstitution·submitted 2 years ago by u/marta_weiss

the dead space question that gets asked weekly, answered properly

PSAbranch of 9 comments

Trying to settle this properly because the thread from last year went in circles. The claim: reconstitution matters. The counter-claim: it is measurement error. Both sides have been asserting it confidently for about 9 months without either producing anything. What would actually settle it is 27 people measuring the…

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This branch

9 comments, started 2 years ago
u/britta_nakamura-16 points·2 years ago

Not convinced. The evidence does not support that reading.

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u/dilara_szabo1 point·2 years ago

Cosigning. The concentration on the vial in marker is load-bearing.

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u/nabila_espinoza1 point·2 years ago

Show the arithmetic. Where did the units come from?

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u/runa_cabrera1 point·2 years ago

bacteriostatic and sterile water are not interchangeable, do not use them that way

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u/ismael_nwosu1 point·2 years ago

Slight fix: the number was 98.1, not 98.0. Decimal point, but a fairly consequential one.

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u/marta_weissOP1 point·2 years ago

This is correct. 2mL versus 6mL is the common mistake.

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u/katrin_marchetti1 point·2 years ago

Are you using a u-100 or u-40 syringe? That changes everything.

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u/alcohol_aversion1 point·2 years ago

dead space is real and the syringe matters

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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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