Inhaled anesthetics 1: pharmacokinetics Flashcards
What are the three groups that we can categorize the inhaled anesthetics into?
ethers
alkanes
gases
At atmospheric pressure and room temperature, the ethers and alkanes exist as
liquids
What are the ethers?
isoflurane, desflurane, and sevoflurane
What are the alkanes?
halothane
At atmospheric pressure and room temperature, the gases exist in
gaseous form
Examples of the gases include
nitrous oxide and xenon
You can identify the halogenated anesthetic molecule by
counting the number of fluorine atoms
How many fluorine atoms does halothane have?
3
How many fluorine atoms does isoflurane have?
5
How many fluorine atoms does desflurane have?
6
How many fluorine atoms does sevoflurane have?
7
Isoflurane has a _______ atom, which increases ______.
chlorine atom, which increases potency
Although sevoflurane is heavily fluorinated, its stil
3x as potent as desflurane
Desflurane is nearly identical to isoflurane, but the chlorine atom is replaced by _________
a fluorine atom
The ethers have a characteristic
“ether bridge”= C-O-C
Since desflurane is fully fluorinated, it has a _____ potency leading to a _____ MAC
decreased potency; increased MAC
Desflurane has a ______ vapor pressure requiring
increased vapor pressure requiring a heated vaporizer
Desflurane has a _____ resistance to biotransformation meaning _____ metabolism
increased resistance to biotransformation meaning decreased metabolism
Fluorination tends to _____ potency
reduce
Sevoflurane is heavily fluorinated but its still 3x as potent as desflurane. This is most likely due to the
bulky propyl side chain
The addition of the heavier chlorine atom with isoflurane results in
increased potency
The chlorine of isoflurane also increases
blood and tissue solubility
______ is the pressure exerted by a vapor in equilibrium with its liquid or solid phase inside of a closed container.
Vapor pressure
Vapor pressure is directly proportional to
temperature
increased temperature results in increased vapor pressure
