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A member asked:

What are the reasons doctors draw so much blood for a blood test?

A doctor has provided 1 answer
Dr. George Klauber answered

Specializes in Pediatric Urology

Depends ?many tests : Complete blood count & routine chemistries together should require no more than 10ml (2 teaspoons full) blood typing & cross-match, if you need surgery where blood may need 2B replaced will require another 5 ml. Other special tests may require further 5 ml. Looks a lot in a syringe or test tube.

Answered 2/13/2015

5.1k views

Thank

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