Quiz 2- Inhalants

Question 1

Is the recovery better with inhalants or injectables

Answer 1

Injectables

Question 2

Why do we use inhalants

Answer 2

It uses the lungs to distribute and eliminate so you don’t have to rely on (and worry about) renal and hepatic metabolism. You can also precisely adjust anesthetic depth and have good control

Question 3

Why don’t we always use inhalants

Answer 3

The equipment is expensive and bulky and the induction process without injectables may be difficult

Question 4

What is our best idea on how inhalants work

Answer 4

The vapors use the partial pressure gradient of the lungs (moves from high to low equilibrium) then it goes into the blood and then to all the organs and brain to provide anesthesia

Question 5

What state are inhalants administered as

Answer 5

Vapors

Question 6

What is the vapor pressure

Answer 6

The pressure exerted by a vapor existing in equilibrium with its liquid state

Question 7

What is the critical temperature

Answer 7

The temperature above which only gas exists

Question 8

What is the boiling point

Answer 8

The temperature at which the vapor pressure equals the vapor pressure of the surroundings

Question 9

How could you determine the partial pressure or the total pressure of a container

Answer 9

Use Dalton’s law of partial pressure
P total= P1+P2+P3….

Question 10

What is the volume percent of inhalants

Answer 10

the relationship between vapor pressure and maximal pressure
(Vapor pressure/barometric pressure (760 if at sea level)) x 100 = vol%

Question 11

What is the blood/gas partition coefficient

Answer 11

The solubility of vapor in the blood aka the ratio of the vol% of vapor in one phase (in the alveoli) compared to the vol% in another (blood) aka how much the vapor likes to stay in the blood

Question 12

Solubility decreases with what

Answer 12

Increase in temperature

Question 13

The lower the partition coefficient of a vapor

Answer 13

The more the vapor wants to stay in the alveoli

Question 14

The lower the solubility of an inhalant

Answer 14

The faster the action- gets through blood and to brain quickly

Question 15

What is the fastest way to gas an animal down

Answer 15

With a nonrebreathing system with sevoflourine (low solubility)

Question 16

What is the potency of a drug measured as

Answer 16

The MAC- the minimum alveolar concentration- the concentration of an inhalant required to prevent movement in 50% of a given population when exposed to a noxious stimulus

Question 17

The lower the Mac

Answer 17

The more potent the anesthetic

Question 18

T/F MAC is additive

Answer 18

True

Question 19

What type of factors increase MAC

Answer 19

Hyperthermia and hypernatremia and increasing excitatory neurotransmitters (happens with drugs like cocaine and amphetamines)

Question 20

What type of factors decrease MAC

Answer 20

Older age, hypothermia, hyponatremia, pregnancy, hypoxemia, severe hypotension, severe hypercarbia (lots of CO2), metabolic acidosis, other anesthetics

Question 21

Does the duration of anesthesia impact MAC

Answer 21

No

Question 22

How do alkalosis, gender, hypertension, and anemia impact MAC

Answer 22

Trick question! They don’t

Question 23

What is the only electrolyte that affects MAC

Answer 23

Sodium (hyper and hyponatremia)

Question 24

What determines if the anesthetic in the brain produces anesthesia

Answer 24

Partial pressure, not concentration

Question 25

How do you increase the delivery of the anesthetic to the alveoli

Answer 25

Increase the inhaled partial pressure (delivery) or increasing the alveolar ventilation

Increase respiratory rate, increase the anesthetic gas (vaporizer flow), minimize the volume of the breathing circuit, increase the oxygen flow rate

Question 26

The partial pressure in the alveoli equals

Answer 26

The partial pressure of the brain

Question 27

How do you decrease the uptake of the anesthetic gas

Answer 27

Decrease the solubility, decrease the cardiac output, decrease the alveolar-venous partial pressure difference

Question 28

If the cardiac output is lower how will it impact the alveolar partial pressure

Answer 28

It will increase the alveolar partial pressure

Question 29

An older calmer dog with a lower heart rate vs. a young dog with a high heart rate, who will need more inhalant

Answer 29

The younger dog with the higher cardiac output will require more inhalant (think of the higher cardaic output being able to “dilute” out the anesthetic gas faster)

Question 30

What is the alveolar-venous partial pressure difference and why is this clinically relevant

Answer 30

The different in the partial pressure of the inhalant in the venous blood vs. alveolar
this impacts how fast the inhalant gets distributed/ moved to the target location (this is how fast you run the marathon vs. the MAC is the length of the marathon)

Question 31

When you flush the line of the anesthesia machine what are you doing

Answer 31

You are changing the partial pressure so it makes the inhalant more likely to want to move out of the animal (wants to move to the area without inhalant gas pressure so moves to the now “clean” anesthesia line)

Question 32

T/F the longer you are under anesthesia will not impact how long it takes to wake up

Answer 32

False, the longer you are under anesthesia the more saturated the body is and the longer it will take to clear the inhalants out of your body

Question 33

Less soluble inhalants are cleared from the body how

Answer 33

They are cleared faster, animal will wake up faster

Question 34

What impacts recovery

Answer 34

How long the animal was under and the solubility of the drug used (so the type of inhalant)

Question 35

Inhalant A is highly soluble in blood and inhalant B is not, how does this impact induction

Answer 35

B will have a faster induction

Question 36

MAC is the measure of what and among multiple inhalants is what

Answer 36

MAC is a measure of potency and is additive among multiple inhalants

Question 37

What is the measure of induction

Answer 37

Solubility