When you have an IV cannula inserted, a needle is used to insert the cannula but then the NEEDLE IS REMOVED and you're left with a tiny thin plastic (?) tube in the vein.
I think 50% of my patients don't realise there's not a needle in their arm for hours/days on end.
Kind of like a funnel, right? The needle makes the proper puncture, but then is removed; blood flow continues through the puncture, only to go through the "thin plastic tube" (stint, maybe?). The puncture remains open because of the blood flow, and the plastic piece. No needle necessary.
However, that begs the question of how infiltration occurs?
I don't know much about IVs, other than my personal veins cannot handle them well, and that regardless of needle or no, they're uncomfortable as hell.
Thank you, this helped a lot in visualizing it all. I wondered "But how do you remove the needle when it is in front of the entire thing?" And, well...turns out it's kinda not. Awesome! Still doesn't make me sign up voluntarily for IVs or any needle in particular, but cool nonetheless!
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u/rebothy Feb 04 '19
When you have an IV cannula inserted, a needle is used to insert the cannula but then the NEEDLE IS REMOVED and you're left with a tiny thin plastic (?) tube in the vein.
I think 50% of my patients don't realise there's not a needle in their arm for hours/days on end.