Chapter 2

Question 1

Addition of ____ made modern inhaled anesthetics differ from the previous ones

changing the physical properties of anesthetic compounds.

Answer 1

Fluorine

Question 2

Isofluorine contains what in its formula?

Answer 2

Chlorine on alpha ethyl group

Question 3

To change Isofluroine to desflurane, requires the substitution of what element?

Answer 3

substitute chlorine for a fluorine

Question 4

What does the change of adding fluorine to desfluorine do to its physical properties?

Answer 4

increases vapor pressure
Makes it more resistant to degradation –> more stable and less toxic

decrease solubility
decrease potency ( increase MAC)

Question 5

_____of fluorinated anesthetics is greater than the presence of absorbance

Answer 5

Stability

Question 6

What does this show?

Answer 6

Desflurane is more stable/ less degradable than Isoflurane

Sevoflurane is only halogenated with fluorine and is degraded by soda lime at higher temperatures to higher extend.

Question 7

Degradation of Soda Lime is caused by

Answer 7

Monovalent bases (NaOH, KOH) and Divalent bases

Question 8

Which monovalent bases do most od the degradation?

Answer 8

NaOH and KOH

Question 9

What is AMSORB ?

Answer 9

new absorbent that does not contain any Na/KOH.

Does not degrade the anesthetics.

Costly

Absorbent capacity (CO2) is half of that of regular soda lime.

Question 10

Degradation product of mainly Isoflurane, desflurane and enflurane is__________

Answer 10

CO - carbon monoxide

Question 11

Why is it important that Soda Lime is 15% water by weight?

Answer 11

Important b/c:
1. Can accelerate rxn with CO2.
2. Protects against degradation of inhaled anesthetics.

Question 12

Only when the absorbent is dry by ______, you get CO production.

Answer 12

90 percent or more

Question 13

What are the causes of dry absorbent?

Answer 13

leave O2 flow on for extended periods of time AND remove the reservoir bag→production of CO

Question 14

Compound A is

Answer 14

a vinyl ether

Question 15

Compound A causes

Answer 15

Kidney toxicity

Question 16

Old School: Per Package of Label of Sevoflurane
Does this still hold true?

Answer 16

Back then:
Don’t use Sevo at less than 1 L/min and if you use it, then only for 2 MAC hours and after that you have to increase Sevo for up to 2L/min.
o ↓flow rate will cause increased temp in the absorbent→ ↑production of compound A.

BUT ALL FALSE NOW

Question 17

How can we ensure the absorbent won’t get dry to avoid the issue w/ CO?

Answer 17

Check canister on a regular basis - can’t really tell

Condensation is misleading

Color change?

Making sure high flow is not going through the system when it is unused.

Question 18

When drying of of the absorbent occurs, what should one do?

Answer 18

Add water ( to the bottom) or replace the absorber!

Question 19

Which anesthetic can spontaneously degrade

Answer 19

Sevofluraneo
It is no longer an issue, as components of the bottle changed!

Question 20

T:F UV light can cause degradation of any anesthetic

Answer 20

True

Question 21

Can inhaled anesthetics hurt environment

Answer 21

Yes

For every one of chlorine atom that is released, it goes to destruct the ozone layer.
o Isoflurane is the ONLY chlorinated anesthetic

Question 22

N20 and abortions

Answer 22

• Occupational exposure: N2O could possibly cause abortions but the amounts are negligible thanks to the scavenging system.
  o Also due to high air turnover in the room: 10-15 turnovers per hour

Dental offices and office based anesthesia have a higher chance

Question 23

• N2O given at high concentrations for prolonged periods of time (for tetanus pts)

Can cause what?

Answer 23

decrease the pain and spasms of muscles can cause aplastic anemia and death.

Question 24

Who are at higher risk of injury for prolonged periods of NO2 at high concentrations?

Answer 24

Patients with Vitamin B12 deficiency (pernicious anemia, real vegetarians) are at higher risk of injury from N2O.

Question 25

Why don’t we use absorbents that do not have Na/K OH in them?

Answer 25

Money and less capacity.

Question 26

T: F
Addition of H2O to Sevoflurane does not alter its potency

Answer 26

T