CRDTS Local Anesthesia Practice Test

The key feature that marks an aspirating syringe is the harpoon. This small projection inside the syringe punctures the rubber stopper of the anesthetic cartridge and grips the stopper so that when you pull back the plunger you can create negative pressure to aspirate. That aspiration step lets you check for blood and avoid giving the anesthetic intravascularly. The barrel, needle hub, and plunger are common to many syringes and don’t by themselves indicate aspiration capability; the harpoon is the specific component that enables the aspirating function.