Why do nurses put the syringe inside veins and not arteries?

A minor technicality, but nurses don't insert a syringe into a vessel, they insert a needle. The syringe is the hollow cylinder that has a plunger inside of it to create negative pressure when pulled back, drawing blood into the chamber. read more

A needle is typically attached to the syringe to do this, but the syringe can also be directly attached to an existing vessel access device such as a newly placed intravenous catheter, a central venous catheter, or an arterial catheter. read more

Veins need not have as thick a wall as arteries because their main function is to be a reserve for the blood until it returns to the heart, which pumps blood into arteries when it contracts. read more

For blood sampling, blood is taken from veins and not arteries because: Veins are close to the surface of the skin. This makes the process easier by avoiding a deep needle plunge just to draw a bit of blood. Arteries, on the other hand, are a tad bit deeper. The walls of veins are thinner than arteries’. read more