Anesthetics

Vocabulary flashcards for pharmacology exam review.

General Anesthesia

A reversible state of CNS depression, resulting in loss of perception and response to external stimuli (pain).

Local Anesthesia

The condition when sensory transmission from a local area to the brain is blocked.

MAC (Minimal Alveolar Concentration)

The end-tidal concentration needed to eliminate movement among 50% of patients challenged by skin incision (ED50). The inverse of MAC is an index of the potency of the anesthetic gas.

Blood/Gas Partition Coefficient

The ratio of the anesthetic concentration in the blood over that in the gas phase at equilibrium.

Induction (General Anesthesia)

The phase of general anesthesia where IV anesthetics are administered to induce anesthesia quickly.

Maintenance (General Anesthesia)

The phase of general anesthesia commonly done with inhaled anesthetics.

Recovery (General Anesthesia)

The phase of general anesthesia involving the washout of inhaled drugs and redistribution of IV drugs.

Redistribution (IV Anesthetics)

Recovery from IV anesthetics is due to redistribution from sites in the CNS to other tissues which will be metabolized and eliminated later.

Local Anesthetics Mechanism of Action

Reversibly block voltage gated sodium channels and thus prevent propagation of action potentials along the nerve fibers.

State (or Use) Dependent Blockade

Local anesthetic drugs bind more readily to sodium channels in an activated state, thus onset of neuronal blockade is faster in neurons that are rapidly firing.