Inhalation Anesthesia 1

Question 1

Naming of covalent bonds is based on what?

Answer 1

How many bonds they share

Question 2

1 Bond between Carbons is called what?

Answer 2

Alkane

Question 3

2 Bonds between carbons is called what?

Answer 3

Alkene

Question 4

3 bonds betweehn carbons is called what?

Answer 4

Alkyne

Question 5

How are ethers chemically unique?

Answer 5

Two or more carbons surrounding an oxygen

Question 6

All inhalation agents have no more than how many carbon atoms?

Answer 6

4

Question 7

What chemical structure property will effect how well the drug produces immobility?

Answer 7

The length of the molecule.

Longer than 4-5 carbons/bond it will lose some of its effect

Question 8

Describe the shape and relationship of length to diameter of inhalation agents:

Answer 8

Shape is spherical/cylindrical with a length less than 1.5 times the diameter.

Question 9

What is the only modern inhaled anesthetic that is not a halogenated hydrocarbon?

Answer 9

Nitrous Oxide

Question 10

What is the only Aliphatic used today?

Answer 10

Halothane

Question 11

What group does isoflurane, desflurane, sevoflurane, and enflurane belong to?

Answer 11

They are all Ethers

Question 12

What is halogenation?

Answer 12

The addition of fluorine (F), chlorine (Cl), bromine (Br), or iodine (I) replaces one or more of the carbon atoms in the chemical structure.

Question 13

How is potency changed when an agent is halogenated?

Answer 13

Potency increases when lower atomic mass atom is exchanged with a higher atomic mass atom.

Question 14

How are arrhythmogenic properties changed when an agent is halogenated?

Answer 14

Arrhythmogenic properties are increased when the agent is more halogenated (more substitutions)

Question 15

How is flammability effected with halogenation?

Answer 15

Flammability is reduced when substituting hydrogens with halogens.

Question 16

How is chemical stability effected with halogenation?

Answer 16

Chemical stability is increased when hydrogens are substituted with halogens.

Question 17

Which inhaled anesthetic strongly resists biodegradation? and why?

Answer 17

Deflurane; because it’s only halogen is fluorine

Question 18

Which group in the Periodic Table of Elements are the halogens from?

Answer 18

Group 17

Question 19

What is unique about the physical properties of all elements in Group 17?

Answer 19

At STP, this group contains elements that are in all three states of matter (solids, liquids, gases)

Question 20

Which anesthetic gas has Bromine as a halogen?

Answer 20

Halothane

Question 21

How many fluorine does Enflurane have?

Answer 21

6

Question 22

How many fluorine does sevoflurane have?

Answer 22

7

Question 23

How many fluorine does desflurane have?

Answer 23

6

Question 24

How many fluorine does isoflurane have?

Answer 24

5

Question 25

Which anesthetic gas has the only degradation rate of 5-8%

Answer 25

Sevoflurane

Question 26

Does increasing or decreasing the number of fluorine atoms on an anesthetic molecule slow biodegradation?

Answer 26

Increasing slows it. | Ex: Desflurane

Question 27

Why is Halothane not being used actively anymore?

Answer 27

1:35,000 Hepatic injury

Question 28

What are the pharmacokinetics of inhaled anesthetics in order chronilogically?

Answer 28

1. Uptake (absorption phase). 2. Biotransformation (Metabolic Phase). 3. Elimination (excretion phase)

Question 29

Of all the inhaled drugs we administer, which two are the only "true gases"?

Answer 29

N20 and O2. | All other agents are vapors or volatile liquids

Question 30

Are inhaled anesthetics ionized or non-ionized?

Answer 30

Non-ionized

Question 31

What is the desired site of action for inhaled anesthetics?

Answer 31

The Central nervous system

Question 32

Define general anesthesia:

Answer 32

Induce and sustain a state of unconsciousness, amnesia, analgesia, immobility.

Question 33

Do inhaled anesthetics eliminate pain?

Answer 33

No; do not have much effect on pain itself. They attenuate the stress response of painful stimuli (HR and BP). Can potentiate other analgesic medications

Question 34

As lipid solubility decreases, what happens to potency?

Answer 34

It decreases. They are directly proportional.

Question 35

What law is associated with lipid solubility and potency relationship?

Answer 35

Meyer-Overton Rule

Question 36

How can inhaled anesthetics be reversed/eliminated?

Answer 36

By application of pressure via a gradient. Administering 100%.

Question 37

As body temperature increases, what happens to anesthetic requirement?

Answer 37

Increases anesthetic requirement.

Question 38

What is the current hypothesis on inhaled anesthetic pharmacodynamics?

Answer 38

They work via diverse mechanisms at diverse sites of action.

Question 39

According to the current theory, what are the two main anatomical sites of action for inhaled anesthetics?

Answer 39

Supraspinal (brain) and spinal

Question 40

How much drug to cause effects of amnesia, unconsciousness, immobility, and sedation?

Answer 40

Least amount drug needed for amnesia. Then sedation. Then unconsciousness. Most drug needed for immobility.

Question 41

What does the oil:gas coefficient tell us about an inhaled anesthetic?

Answer 41

How well the drug dissolves in a lipid which is a measure of potency. Higher the oil:gas coefficient, the higher the potency.

Question 42

What does the blood:gas coefficient tell us about an inhaled anesthetic?

Answer 42

How easily the drug dissolves in blood which is a measure of how quickly the drug will get to brain. The higher this number, the slower it takes for the brain to see it.

Question 43

How do inhaled anesthetics produce anesthesia?

Answer 43

Enhancing the function of inhibitory ion channels and by blocking the function of excitatory ion channels.

Question 44

What does enhancing of inhibitory ion channels do to the neuron?

Answer 44

It leads to hyperpolarization.

Question 45

What does blocking the function of excitatory ion channels prevent?

Answer 45

Prevents depolarization of the neuron by preventing passage of positive charges into the neuron.

Question 46

What are the two inhibitory ion channels?

Answer 46

Glycine and GABA

Question 47

Which inhibitory ion channel affects immobility and is located in spinal cord?

Answer 47

Glycine

Question 48

Which inhibitory ion channel is associated with hypnosis?

Answer 48

GABA

Question 49

Where are the GABA sites located?

Answer 49

In between the Alpha1 and Beta2

Question 50

What is an example of an excitatory channel?

Answer 50

Glutamate. | Ligand gated receptors NMDA

Question 51

Is immobility measurable?

Answer 51

Yes; through MAC

Question 52

How is immobility achieved with inhaled anesthetics?

Answer 52

Activation of descending noradrenergic pathways. Activation of these pathways inhibit nociceptive input in the dorsal horn of the spinal cord.

Question 53

How is amnesia achieved with inhaled anesthetics?

Answer 53

Supraspinal structures such as the amygdala, hippocampus, and cortex are considered highly probable targets of inhaled anesthetics.

Question 54

Does amnesia have a reliable measure?

Answer 54

No; there is no definitive way to ensure amnesia.

Question 55

At equilibrium of anesthetic gas, what is the PP of the lung in relation to the blood and the brain?

Answer 55

The Lung PP equals the Blood PP which equals the Brain PP

Question 56

Does a highly blood soluble drug get eliminated faster or slower?

Answer 56

Faster | ex: Nitrous Oxide

Question 57

Define Vapor pressure:

Answer 57

At equilibrium, the pressure exerted by the molecular collisions of the gas against the container walls.

Question 58

Is vapor pressure directly or inversely proportional to temperature?

Answer 58

It is directly proportional to temperature.

Question 59

For any mixture of gases in a closed container, each gas exerts a pressure proportional to its fractional mass. This is called its {blank}?

Answer 59

Partial pressure

Question 60

What is Dalton's Law?

Answer 60

The sum of the partial pressures of each gas in a mixture of a gases equals the total pressure of the entire mixture

Question 61

What is Henry's Law?

Answer 61

The relationship of concentration of a gas with which the solution is in equilibrium

Question 62

Which Law applies to the movement to equilibrium?

Answer 62

Henry's Law

Question 63

Which law applies to the PP of gases?

Answer 63

Dalton's law

Question 64

Ptotal=Pgas1+Pgas2+Pgas3 is a representation of what?

Answer 64

Dalton's Theory of partial pressures.

Question 65

What is the solubility coefficient?

Answer 65

For any gas in equilibrium with a liquid, a certain volume of that gas dissolves in a given volume of liquid.

Question 66

What is MAC of Nitrous Oxide?

Answer 66

104%

Question 67

What is MAC of sevoflurane?

Answer 67

2.2%

Question 68

What is MAC of desflurane?

Answer 68

6.0%

Question 69

What is MAC of isoflurane?

Answer 69

1.15%

Question 70

The concentration of each gas in a mixture of gases in solution depends on two things: what are they?

Answer 70

1. Its partial pressure in the gas phase in equilibrium with the solution. 2. Its solubility within that solution

Question 71

What is the most direct measurement of the Brain's amount of an inhaled anesthetic?

Answer 71

End Tidal Percentage of the gas.

Question 72

Do inhaled anesthetics equilibrate based on their concentration or their partial pressures in each tissue?

Answer 72

Partial pressures

Question 73

Which inhaled anesthetic can be used for very large patients because it does not get "stuck" in the fat reservoirs?

Answer 73

Desflurane

Question 74

Distribution of cardiac output to different tissues: | Vessel-rich group, muscle, fat?

Answer 74

Vessel-rich group 10% body mass and 75% CO. | Muscle is 50% body mass and 19% CO. Fat is 20% body mass and 6% CO

Question 75

Fractional volume definition:

Answer 75

In the gas phase, fractional concentration (% by volume) is equal to the partial pressure divided by ambient pressure.