Why does the nurse have to find a vein to draw blood? What’s the difference between that and the blood that shows up if I had a cut on my arm?

Question

Deleted my other question, realized it was too vague and not relevant to my actual question.

In: Biology

Answer 1

The blood you see when you cut your arm is from the tiny blood vessels called capillaries that are in your skin. They’re so tiny there’s not a way to efficiently collect the quantity of blood needed. Hitting a vein is the best way to do so.