why does air come into the syringe?

[Venom57]

why does air come into the syringe when i pull back to check if i hit a vein. Ill take it over blood, but why wouldnt it be a liquid of some sort?

[warpalien]

im assuming its air you pushed in when you pushed the needle in

[jamesbrosky]

oh yeah, I never thought of that.
well I dunno actually, I can pull a lot of air

[Got Gear?]

It's not air, it's a vacum. There's a huge difference.

Like in "outer-space"

[AZ1]

There is no air coming into the syringe. It is space, not air.

By pulling back you are creating suction which if there is no blood to fill the space (thats good), it creates empty space called a vacuum.

[bowbow]

If you notice it's actually hard to pull back when asperating so you are creating a vacuum.

[localboyz]

its a good thing. if you pull back blood, that means you hit a vein, which is not good, and you should pick another spot.

[Blackfoot]

That's a funny question bro. I know what you mean. I thought the same thing a while back. But it's a good thing.

[jamesbrosky]

Originally posted by Got Gear?
It's not air, it's a vacum. There's a huge difference.

Like in "outer-space"

ohyeah
Ill take one order of "duhhhh" for that one.