Vaporizers

Question 1

Only inhalation agent that can be used for induction

Answer 1

Sevoflurane - ultane

Question 2

Known for rapid induction and awakening

Answer 2

Sevoflurane (Ultane®)

Question 3

What 2 things is sevo used for?

Answer 3

Used for peds/inhalation
induction

Question 4

Can react with CO2 absorbents to form nephrotoxic

compound A.

Answer 4

Sevoflurane (Ultane®)

Question 5

Requires specially designed electrically heated

vaporizer

Answer 5

Desflurane (Suprane®)

Question 6

2 bad side effects desflurane causes:

Answer 6

Airway irritant (during induction,
combine with IV agents)
Can cause tachycardia (caution
with coronary artery disease)

Question 7

Rapid elimination of des results in

Answer 7

quick awakening

Question 8

Once considered the “gold standard” of
inhalation agents, especially for
neurosurgery

Answer 8

Isoflurane (Forane®)

Question 9

What BAD thing can isoflurane cause?

Answer 9

Can cause coronary artery steal
syndrome

Question 10

isoflurane causes significant

Answer 10

peripheral vasodilation

can cause hypotension

Question 11

was agent of choice
for inhalation induction
(now replaced by sevoflurane)

Answer 11

Halothane

Question 12

Halothane is good for use in asthmatics, why?

Answer 12

Potent bronchodilator

Question 13

What serious implication did halothane have on organ that is not the heart?

Answer 13

Halothane hepatitis

Question 14

Why does halothane Increase risk of dysrhythmias

Answer 14

decrease sensitivity to catecholamines - real bad if local anesthetic and epi given

Question 15

halothane Emergence is significantly

Answer 15

slower than other agents

Question 16

NOT a volatile agent
Used to supplement inhalation
agents

Answer 16

NITROUS OXIDE

Question 17

Only inhalation agent with
sympathomimetic activity

Answer 17

nitrous

Question 18

What is important concept to understand about nitrous?

Answer 18

Diffuses into air-filled spaces
(increases pressure)

Question 19

what should be given during emergence to avoid
diffusion hypoxia with nitrous

Answer 19

high fio2

Question 20

A device for converting a volatile

anesthetic agent into breathable vapor

Answer 20

vaporizer

Question 21

where are vaporizers located?

Answer 21

between flow meters and common gas outlet

Question 22

Gaseous molecules from a
substance that is liquid at room
temp at 1 atm (760 mmHg)
pressure

Answer 22

vapor

Question 23

if you increase temperature, what happens to vaporization?

Answer 23

it increases

Question 24

if you increase vaporization, what happens to the liquid below?

Answer 24

decreases the temp of the liquid below

Question 25

if you decrease temperature, what happens to vaporization?

Answer 25

will decrease vaporization unless heat is added (increased temp = increased vaporization) [think energy]

Question 26

Equilibrium pressure of a vapor above its liquid or solid

Answer 26

Vapor Pressure

Question 27

This term is temperature and agent specific?

Answer 27

Vapor Pressure

Question 28

When equilibrium is met, the anesthetic is at its

Answer 28

saturated vapor pressure

Question 29

why do we want volatiles at saturated vapor pressure

Answer 29

so that we can control the amount of agent that we give

Question 30

when you increase temperature, what happens to vapor pressure?

Answer 30

vapor pressure increases

Question 31

Temp at which vapor pressure = atm pressure

Answer 31

Boiling Point

Question 32

when you decrease atm pressure, what happens to boiling point?

Answer 32

decreases boiling point | [things will boil at lower temp]

Question 33

Calories needed to convert 1g of liquid to vapor without temperature change in the remaining liquid

Answer 33

Latent Heat of Vaporization

Question 34

Calories needed to increase the temperature of 1g of a | substance by 1°C

Answer 34

Specific Heat

Question 35

what do we want our vaporizers to be constructed with?

Answer 35

materials with high specific heat and conductivity to minimize temp changes associated with vaporization

Question 36

Alveolar concentration that prevents movement in 50% of patients in response to surgical stimuli (incision)

Answer 36

MAC (minimum alveolar concentration):

Question 37

Measured-flow (operator controls flow bubbled | through agent from 2nd O2 flowmeter)

Answer 37

COPPER KETTLE (VERNITROL)

Question 38

what material has high specific heat (heat needed to raise 1g by 1°C) and high thermal conductivity (speed of heat conductance)

Answer 38

Copper

Question 39

Amount of fresh gas allowed to come in contact with liquid vapor is controlled

Answer 39

VARIABLE-BYPASS

Question 40

with VARIABLE-BYPASS Gas entering the vaporizing chamber is

Answer 40

a carrier gas

Question 41

what is Splitting ratio determined by

Answer 41

internal resistance to flow (controlled by vaporizer dial) and temp compensating mechanism (inside vaporizer)

Question 42

what 2 things cause full saturation in variable bypass vaporizer?

Answer 42

Wicks/baffles

Question 43

Saturated gas combines with fresh gas at

Answer 43

vaporizer outlet to consistently produce final desired concentration regardless of total fresh gas flow (FGF)

Question 44

does FGF have anything to do with % of volatile pt receives when using variable bypass vaporizer?

Answer 44

NO NO NO | independent of FGF

Question 45

explain Temperature Compensation with variable bypass vaporizers

Answer 45

temp change causes strip bending which produces ↑ or ↓ in gas passing through vaporizer

Question 46

Vapor Blender vaporizer

Answer 46

ELECTRONIC (TEC 6)

Question 47

requires electronic (heated) vaporizer, why?

Answer 47

desflurane, so it doesn't crystalize

Question 48

mechanism of ELECTRONIC (TEC 6) with des?

Answer 48

injects tiny amounts of vaporizer into FGF that goes to pt, no carrier gas used, no flow going into vaporizer - just injects

Question 49

what is electronic tec 6 controlled by?

Answer 49

dial and internal transducer

Question 50

only vaporizer you can refill while still on?

Answer 50

Tec 6

Question 51

One central electronic control mechanism for all agents

Answer 51

ELECTRONIC (ALADIN CASSETTE)

Question 52

Variable bypass, even for desflurane

Answer 52

ELECTRONIC (ALADIN CASSETTE)

Question 53

what happens if A sevoflurane (VP: 157) vaporizer was filled with isoflurane (VP: 240)

Answer 53

you would give less sevo bc of the lower VP | [sevo does not want to escape as badly]

Question 54

what happens if you fill isoflurane (vp 240) with sevoflurance (vp 157)

Answer 54

you would give a lethal dose of the sevo

Question 55

what are the 6 safety mechanisms?

Answer 55

- Color-coding (although not FDA required) - Keyed fillers - Low filling port - Secured vaporizers (minimizes tipping) - Concentration dial increases output in all when rotated counterclockwise - Interlocks

Question 56

Ensures that only one vaporizer is turned on and that gas can only enter if vaporizer in an on position

Answer 56

VAPORIZER INTERLOCK

Question 57

5 risks of vaporizers?

Answer 57

1. tipping 2. out of calibration 3. leaks 4. pumping 5. electronic dysfunction

Question 58

what side are vaporizers on anesthesia machine?

Answer 58

low pressure side