1. VNTE Prep
Anesthetic Review

2. Vapor Pressure
A measure of the tendency of a molecule to escape from the liquid phase to the vapor or gas phase.
Determines how readily the anesthetic liquid evaporates in the anesthetic machine vaporizer.
Agents w/ high vapor pressure are considered to be volatile.

3. Vapor Pressure
High vapor pressure = Evaporate readily = Must use precision vaporizer
Low vapor pressure = Don’t evaporate as readily = Does not require a precision vaporizer

4. Solubility Coefficient
A measurement of the distribution of the inhalation agent between the blood and gas phases in the body.
Agents w/ a high solubility coefficients take longer to induce and recover from anesthesia.
Agents w/ a high solubility coefficient are extremely soluble in blood & tissues – they do not build up in high levels in the alveoli.

5. Solubility Coefficient
Agents w/ a low solubility coefficient have rapid induction & recovery from anesthesia.
Agents w/ a low solubility coefficient are less soluble in blood & tissues - they build up in the alveoli in sufficient levels
Associated w/ the speed of induction, recovery, & change in anesthetic depth

6. Minimum Alveolar Concentration
A measurement of the potency of an agent
The lowest concentration of an anesthetic agent that produces no response to painful stimuli in 50% of the patients.
The lower the MAC the more potent the agent (It takes less to reach desired effect)

7. Minimum Alveolar Concentration
It takes a higher concentration of an agent w/ a high MAC to maintain a similar anesthetic depth when compared to an agent w/ a lower MAC.
It is more cost effective to use an anesthetic agent w/ a low MAC.

8. Vaporizer Out of Circuit
AKA – VOC
Vaporizer is not in the breathing circuit
- Circuit includes: unidirectional valves,
hoses, CO2 absorber canister, APL
valve, reservoir bag
Precision vaporizers
Must be placed out of the breathing circuit due to high resistance to gas flow

9. Vaporizer in Circuit AKA – VIC Vaporizer is part of the circuit
Nonprecision vaporizers
Offer little resistance to gas flow thru the breathing circuit