Lecture 16: Inhaled Anesthetics

Question 1

What do inhaled anesthetics do

Answer 1

1. Depress CNS
2. Decrease excitatory NT release- inhibit nicotinic receptors and activate K+ channels- hyperpolarize

Question 2

Potency is proportional to ___solubility

Answer 2

Lipid

Question 3

The partial pressure of the gas is inversely proportional to the ___

Answer 3

Solubility of the gas in solvent

Question 4

The solubility is expressed b the ____coefficient

Answer 4

Blood: gas partition coefficient

Question 5

The more lipid soluble an anesthetic the more ___it is

Answer 5

Potent

Question 6

Drugs that are very soluble in blood will take ___to reach equilibrium and get to brain

Answer 6

Longer

Question 7

Drugs that are less soluble in blood will have a ___onset of action and more __recovery

Answer 7

Faster, rapid

Question 8

Drugs that have a ___blood pass partition equilibrate more rapidly than those with ___one

Answer 8

Low, higher

Question 9

More ventilation results in ___

Answer 9

More anesthetic gets to alveoli- faster induction

Question 10

Partial pressure in the blood can be increased by ___rate of ventilation during induction

Answer 10

Increasing

Question 11

The brain has a ____level of perfusion therefore drug gets in quickly

Answer 11

High

Question 12

Areas with high perfusion will clear the drug more ___when gas is turned off

Answer 12

Quickly

Question 13

Inhalants are eliminated through __

Answer 13

Lung

Question 14

Entry and loss to and from fat is ___because perfusion is low

Answer 14

Slow

Question 15

Low solubility in blood= ___elimination

Answer 15

Fast

Question 16

Elimination of anesthetics are faster if blood: gas coefficient is ___

Answer 16

Low

Question 17

What is 1 MAC of inhaled anesthetic defined as

Answer 17

Concentration at 1atm that prevents skeletal muscle movement in response to very painful stimuli in 50% of population

Question 18

The lower the MAC the more __the drug

Answer 18

Potent

Question 19

___MAC will cause anesthesia in 95%

Answer 19

1.2

Question 20

___MAC will cause anesthesia in 100%

Answer 20

1.5

Question 21

Which inhalant has a an analgesic effect but is not potent enough to produce surgical anesthesia

Answer 21

NO2

Question 22

How does NO2 effect cardiovascular system

Answer 22

Minimal effects, it will depress myocardial function but also increase SNS stimulation so effect is minimal

Question 23

How does NO2 affect BP

Answer 23

Decreases

Question 24

Diffusion hypoxia is associated with which anesthetic and what do you do to prevent this

Answer 24

NO2
Administer 100% O2 for short time when N2O is turned off to prevent hypoxia

Question 25

How does Isoflurane affect cardiovascular function and BP

Answer 25

Depresses cardiovascular function and decreases BP

Question 26

How does Isoflurane affect respiratory rate and tidal volume

Answer 26

Decreases both

Question 27

With Isoflurane cerebral blood flow is maintained at what MAC

Answer 27

Less than 1.2

Question 28

T or F: Isoflurane has muscle relaxant properties

Answer 28

True

Question 29

Isoflurane is labeled for what species

Answer 29

Dogs and horses

Question 30

What anesthetic can be used in combination with O2 for status epilepticus that are refractory to benzodiazepine. And what should you be cautious about when using this gas to control seizures

Answer 30

Isoflurane and keep below 1.2 MAC or will increase ICP

Question 31

Why is Isoflurane not good for induction

Answer 31

May causer bronchospasm

Question 32

What anesthetic gases can produce malignant hyperthermia

Answer 32

Isoflurane and sevoflurane

Question 33

How does sevoflurane affect cardiovascular system, BP, and ventilation

Answer 33

Decrease stroke volume, depresses myocardial contractility, decreases BP, decreases ventilation

Question 34

What type of vaporizer is required for deslfurane

Answer 34

Heated

Question 35

Desflurane irritates the ___ and may cause ___ (like iso)

Answer 35

Airway, bronchospasm

Question 36

How does desflurane affect TV and RR

Answer 36

Decreases TV and increases RR

Question 37

How does desflurane affect BP and HR

Answer 37

Decreases BP, but increase HR which maintains perfusion

Question 38

How does desflurane affect ICP and what can you do to prevent

Answer 38

Increase ICP- hyperventilate to prevent

Question 39

What does malignant hyperthermia cause

Answer 39

Hypepyrexia and muscle rigidity

Question 40

What is tx for malignant hyperthermia

Answer 40

IV Dantrolene and cooling

Question 41

What anesthetic is preferred in cats

Answer 41

Ketamine

Question 42

In cats propofol can cause ___if given repeatedly

Answer 42

Heinz Body anemia

Question 43

What can etomidate cause in cats

Answer 43

Hemolysis

Question 44

Propofol, ketamine and tiletamine all cause ___in horses and pretreat with ___

Answer 44

Excitement, pretreat with alpha2 agonists

Question 45

In horses ___can be combined with xylazine, guaifenesin and acepromazine

Answer 45

Alfaxalone

Question 46

___anesthetics are not preferred in horses

Answer 46

Inhalation

Question 47

Which inhalant causes respiratory depression and slowed recovery in horses

Answer 47

Sevoflurane

Question 48

answer the questions in photo

Answer 48

1. B- lowest MAC 2. A- highest MAC 3. E- lowest B/G 4. B- highest B/G

Question 49

Answer questions in photo

Answer 49

1. C 2. E