Why is aspiration performed during local anesthesia injections?

• A. To confirm intravascular injection
• B. To speed onset
• C. To check for intravascular placement before depositing
• D. To determine potency

Answer: (C)

Aspiration is done to ensure the needle tip is not inside a blood vessel before you deposit the anesthetic. By pulling back on the plunger after penetrating the tissue, you check for blood in the syringe. If blood appears, the needle is in a vessel and you reposition and re-aspirate before injecting. This protects the patient from accidental intravascular injection, which can cause rapid systemic uptake of the anesthetic and lead to serious reactions such as cardiovascular or CNS toxicity. The goal is safety, not to speed onset, determine potency, or verify placement after deposition; even with negative aspiration, injections should still be delivered in small amounts and with care.