How to aspirate the right way


From SSB:

Alright....ive been reading the "injection into vein" thread and i noticed that alot of people are pulling the plunger back to a certain extend. Having been a hematoloy lab tech, and a phlebotomist, i am going to explain the "art" behind the perfect aspiration..

First, you must understand that the blood circulatory system is under pressure at all times within the minimal vaccum should cause a draw effect.

Having said that, you must also realize that if you create too big of a vaccum with a syringe inside the vein, you will collapse the vein as you will suck the vein wall right against the bevel of the syringe and that will create a plunger effect.

NOW...since you know the above, now we can start explaining how to aspirate...

What one should do is either just use their finger and flick the plunger or push gently upwards (move the plunger no more than a millimeter) this vaccum draw should create a vaccum effect that you will end up with a fair bit of blood in the syringe already....If you pull to hard and too fast, you will just end up with no blood in the syringe because you created the plunger effect mentioned above...and youll just inject into the blood vessel.

Hope this clarifys how to aspirate...
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very interesting, seems I've been doing it wrong. So a small flick at the top of the syringe should say it all? That's good news for me, since I find aspirating hard in certain areas.
Kinda glad I found this I was just going to make a post.

Tonight I injected 200mg prop in my butt, and I normally dont aspirate and now I will for sure, anyways, when I pulled out I had blood spraying everywhere! Kinda freaked me out, but just to make sure, are there any things that could cause problems? First time this has ever happened to me.

I should add, I felt nothing wrong afterwards, been about an hour now.
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happen to me, you just went through a vein. that was the last time i ever injected into the glute.....
Dude, this post is why I love this forum. great stuff, I always wondered about how much to pull back, ect.
i have only hit on a vein once and i didnt even have to pull back for the blood to enter into the syringe, so i totally agree with the op.
I've never pulled the plunger back hard I always just use the tip of my index finger and flick it up. The bloods under pressure if it's in a vain it will practically fill itself.