The primary effects of a vasopressor used with local anesthetic include:

The primary effects of a vasopressor used with local anesthetic include:

• A. Increase duration of anesthesia, hemostasis, reduce systemic toxicity
• B. Decrease duration
• C. Increase toxicity
• D. No effect

Answer: (A)

Adding a vasopressor to a local anesthetic creates local vasoconstriction at the injection site. That reduced blood flow slows the anesthetic’s uptake into the bloodstream, so the nerve remains blocked for a longer period. The vasoconstriction also reduces bleeding in the area, giving better hemostasis during the procedure. With less anesthetic entering the circulation, the peak plasma concentration is lower, decreasing the risk of systemic toxicity. These combined effects—prolonged anesthesia, improved hemostasis, and reduced systemic exposure—are the primary benefits.

Adding a vasopressor to a local anesthetic creates local vasoconstriction at the injection site. That reduced blood flow slows the anesthetic’s uptake into the bloodstream, so the nerve remains blocked for a longer period. The vasoconstriction also reduces bleeding in the area, giving better hemostasis during the procedure. With less anesthetic entering the circulation, the peak plasma concentration is lower, decreasing the risk of systemic toxicity. These combined effects—prolonged anesthesia, improved hemostasis, and reduced systemic exposure—are the primary benefits.