Inhalation Agents

Question 1

Uptake

Answer 1

removal from the lungs

Question 2

Increase in uptake

Answer 2

delay anesthetic action

Question 3

Increase of Input of anesthetic

Answer 3

Help speed up anesthetic action and fall asleep

Question 4

The more dissolved in the blood

Answer 4

the more time patient takes to fall asleep

Question 5

Blood solubility

Answer 5

affects delivery.

Question 6

Vehicle absorption and elimination

Answer 6

Lungs

Question 7

Desflurane and N2O

Answer 7

minimal metabolism

Question 8

Measurable

Answer 8

Inspired concentration

and expired concentration

Question 9

At equillibration of FA/FI

Answer 9

any changes in the machine occurs quickly in the brain

Question 10

N2O is the only gas

Answer 10

at room temperature

Question 11

The larger breathing circuit

Answer 11

Hinders anesthetic, can work against wor

Question 12

Fraction inspired

Answer 12

The gas then enters the inspiratory limb of the circuit to be inspired
by the patient

Question 13

Fraction alveolar FA.

Answer 13

The inspired concentration is then taken into the lungs through spontaneous or controlled ventilation and transferred to the alveoli

Question 14

VA are respiratory

Answer 14

Depressant

Question 15

Too much anesthetics

Answer 15

breathing will decline, protecting mechanism of the patient

Question 16

**2 effects of VA:

Answer 16

Myocardial depressant

Respiratory depressants

Question 17

The more soluble in the BLOOD

Answer 17

the longer time to fall asleep

Question 18

BLOOD GAS PARTITION of Des

Answer 18

1.4

Question 19

BG partition of 0.5 (fills in quicker)

Answer 19

At equillibration, for every 2 molecules in alveolar gas, 1 moleculres will be in the blood

Question 20

BG partition of 1.5 (fills in slower)

Answer 20

2 molecules in alveolar gas, 3 molecules in the blood.

Question 21

Partial pressure determined by

Answer 21

Solubility in blood and solubility in the tissues.

Question 22

Relationships

Answer 22

FD> FI > FA> pressure arterial > pressure brain> Pressure venous

Question 23

Agents with a low blood to gas partition coefficient equilibrate_________ than do agents with a high blood to gas partition coefficient if other variable are held constant.

Answer 23

more rapidly

Question 24

Mass spectometry

Answer 24

How much in and how much out

Question 25

FA/FI has to be close to

Answer 25

1

Question 26

ISoflurane very

Answer 26

1.5

Question 27

Des, Nitrous, Sevo

Answer 27

fast onset and offset

Question 28

Each 1% of agent at normal atmospheric pressure represents 1% of

Answer 28

760 mm Hg or | 7.6 mm Hg pressure

Question 29

A blood gas solubility of 1.0 indicates that at equilibrium a concentration of anesthetic in arterial blood of 1% would mean

Answer 29

that the concentration in the lung would be 1%

Question 30

If the blood to gas partition coefficient is 2.0, the concentration in the blood must

Answer 30

equal 2% to achieve a concentration in the lung of 1%.

Question 31

iF B/G partition is 0.5 , how many molecules would it take for 1 molecule in blood

Answer 31

4

Question 32

follows Formulae | • Uptake=

Answer 32

cardiac output (Q) X concentration gradient (alveolar to venous partial pressure difference) X blood to gas solubility (λ)

Question 33

Higher cardiac output in VA

Answer 33

slower induction time

Question 34

For induction though, higher CO

Answer 34

Faster induction time

Question 35

Alveolar-venous measure

Answer 35

Venous measure how much in the tissue | Alveolar

Question 36

Sevo, NITROUS , DESp

Answer 36

Poorly soluble less uptake into blood fall asleep faster

Question 37

Sevo, NITROUS , DESFlurane

Answer 37

Poorly soluble less uptake into blood fall asleep faster

Question 38

Increasing FD:

Answer 38

overpressuring Increasing the concentration on the vaporizer to supraphysiologic levels (Caution is warranted)

Question 39

Increasing FGF

Answer 39

Increasing the fresh flow rates via | anesthesia machine

Question 40

Increasing alveolar ventilation

Answer 40

Increasing rate and/or tidal volume (note tidal volume must not exceed dead space)

Question 41

Concentrating effect

Answer 41

The administration of a gas in high concentrations will increase its own concentration and the rate of rise in FA/FI

Question 42

Second gas effect

Answer 42

The administration of a gas in high concentration will increase the rate of rise of the FA/FI of companion gas

Question 43

Risk of DELIVERING TOO MUCH ANESTHETIC

Answer 43

Hypotension

Question 44

Delivery high to low

Answer 44

FD >FI>FA>Pa>Pbr>Pv

Question 45

B/G partition less than 1

Answer 45

Faster sleep

Question 46

For example, isoflurane has a blood-gas partition coefficient of 1.4. This means that,

Answer 46

at equilibrium, the isoflurane concentration in the | blood would be 1.4 times the concentration in the gas (alveolar) phase

Question 47

The principle objective is to achieve

Answer 47

a constant and optimal brain partial pressure of the inhaled anesthetic

Question 48

The alveolar partial pressure (PA) of the inhaled anesthetic | mirrors

Answer 48

the brain partial pressure (Pbr)

Question 49

Transfer of inhaled anesthetic from machine to alveoli (anesthetic input) FIAC

Answer 49

* Inspired partial pressure * Alveoli ventilation * Characteristics of breathing system * Functional residual capacity

Question 50

Ratio that determines delivry

Answer 50

Alveolar ventilation | Functional Residual Capacity

Question 51

Transfer of inhaled anesthetic from alveoli to arterial blood •

Answer 51

****Blood gas partition coefficient • Cardiac output • Alveolar-to-venous partial pressure difference

Question 52

Transfer of inhaled anesthetic from arterial blood to brain (anesthetic loss)

Answer 52

* Brain:blood partition coefficient * Cerebral blood flow * Arterial-to-venous pressure difference

Question 53

The PA and ultimately the Pbr of an inhaled | anesthetic are determined

Answer 53

by input (delivery) into alveoli MINUS (uptake) loss of the drug from alveoli into arterial blood.

Question 54

****Inhaled partial pressure (PI) is high during initial | administration to offset _____________.it is then decreased during maintenance to match the ____________

Answer 54

uptake from alveoli into arterial blood (similar to administering IV loading dose); Decreased uptake as tissues accumulate anesthetic.

Question 55

Initial fraction of VA, More important for drugs that are MORE SOLUBLE (HIGHER PARTITION COEFFICIENT)

Answer 55

ISOFLURANE

Question 56

A high PI delivered from the anesthetic machine is required during_______• This will help__________ • With time, as uptake into the blood decreases, the PI should be

Answer 56

- initial administration to offset the impact of uptake. - accelerate induction of anesthesia. - decreased to match the decreased anesthetic uptake and therefore maintain a constant optimal Pbr.

Question 57

what is the second gas effect?

Answer 57

Ability of high volume uptake of one gas (first-gas) to accelerate the rate of increase on PA of a concurrently administered companion gas (second gas).

Question 58

Simultaneous administration of slower agent, such as halothane with a faster drug such as

Answer 58

``` nitrous oxide (in high concentrations) can speed the onset of the slower agent. ```

Question 59

Controlled ventilation of the lungs that results in | hyperventilation and decreased venous return will________

Answer 59

accelerates the rate of increase in PA by virtue of increased input (increased VA) and decreased uptake (decreased cardiac output).

Question 60

OIL: GA

Answer 60

Affect potency

Question 61

KNow B/G partition

Answer 61

Sevo des, nitrous, iso

Question 62

Opiates __________MAC

Answer 62

decrease