What is the dead-space loss per draw with a 27G needle at 20 mg/mL?

Asked 27 Apr 2024Modified 2.3 years agoViewed 7.3k times

Concretely: a 27G needle · 20 mg/mL.

I want the working, not the result — I need to be able to redo it with different numbers.

I care about the precision as well as the value — I want to know how many figures are real.

How many significant figures are actually justified here?

The volume trapped in the syringe hub and needle after the plunger bottoms out. It is small in absolute terms and large as a fraction of a small…

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askedcake_intact18k2827 Apr 2024

5I would add a sentence about sterility here, since it is the thing people skip. – sian_llewellyn 4 months ago

4The placebo-arm figure is the part everyone omits. – assay_blank 3 months ago

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This question has not been answered. It has been viewed 7.3k times, which suggests the question is of interest and the answer is not obvious. If you can answer it with a source or a worked calculation, it will be read. See how to ask and answer.

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