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What is the dead-space loss per draw with a 18G drawing needle at 4 mg/mL?

Asked 15 Dec 2025Modified 7 months agoViewed 7.7k times
18

Numbers first: an 18G drawing needle · 4 mg/mL.

This should be a straightforward calculation and I keep getting two different answers.

The numbers are arbitrary; the method is what I am after.

What is the general form of this calculation?

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askedmarta_szymanska17k3815 Dec 2025

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