CO2 Absorber Flashcards

1
Q

Carbon dioxide absorber

A
  • chemically neutralizes CO2
  • contains a base that neutralizes acid
  • acid = carbonic acid
  • base = hydroxide of alkali or alkaline earth metal (NaOH, KOH, CaOH)
  • end product = water + carbonate + heat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are some advantages and disadvantages to CO2 absorbers

A
  • conserve heat/humidity
  • conserve anesthestic gases
  • can get exhausted and need to be changed frequently
  • become dessicated and you dont know it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name 4 types of CO2 absorbants

A
  • Potassium hydroxide Lyme (soda lime)
  • Calcium hydroxide Lyme (amsorb plus)
  • Baralyme
  • Litholyme
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the components that make up Soda Lyme?

A
  • 4% sodium hydroxide
  • 1% potassium hydroxide
  • 0.2% silica (prevents dust)
  • 15% water
  • 80% calcium hydroxide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How much CO2 can Soda Lime absorb

A

-26L of CO2 / 100g of absorbent granules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

-How much CO2 does CaOH2 absorb?

A

1lb of CaOH2 can absorb 0.59lbs of CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Soda Lime Reaction

A
  1. CO2 —> H2O = H2CO3
  2. H2CO3 —> NaOH = NaCO3 + H2O + heat
  3. H2CO3 —> KOH = KCO3 + H2O + heat
  4. NaCO3 —> CaOH = Ca3(CO3)2 NaOH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the components that make up Amsorb?

A
  • 80% calcium hydroxide
  • 16% water
  • 1-4% calcium chloride (moisturizer)
  • calcium sulfate and polyvinylpyrrolidine added harshness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How much CO2 can Amsorb absorb?

A
  • capable of absorbing 10L of CO2 / 100g of granules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Calcium hydroxide reaction

A
  1. CO2 —> H2O = H2CO3

2. H2CO3 —> CaOH2 = CaCO3 + 2H20 + heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the advantages and disadvantages of Amsorb?

A
  • Advantages: doesn’t create carbon monoxide or compound A and there is low fire risk
  • Disadvantages: must be changed out more frequently, less CO2 absorbed than soda lime, more expensive
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the components of BaraLyme

A
20% BaOH
80% CaOH
*small amounts of KOH and NaOH may be added*
-mesh size 4-8
-no hardening agent added
-no water
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How much CO2 can Soda Lime absorb

A

-26 L CO2 / 100g of granules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the components of Litholyme

A

-75% lithium hydroxide
-12-19% H2O
<3% lithium chloride

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How much CO2 does Litholyme absorb?

A

-1lb of LiOH absorbs 0.9 lbs of CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

CO2 absorber exhaustion

A
  • when the pH level falls below 10.3 the absorber turns ethyl violet
  • when not in use it will go back to white
  • these should be replaced at 50-70% exhaustion
  • *increasing MV does not help if you are rebreathing
  • *increase FGF while you change CO2 absorber
17
Q

Mesh size

A
  • size 4-8; determines which granules can go through
  • irregular granules have larger surface area
  • small granules have increased surface area and resistance
  • larger granules have smaller surface area and resistance
18
Q

Granule hardness

A

19
Q

Channeling

A
  • the preferential flow of gas exhaled into the CO2 absorber through channels that result of loosely packed particles
  • these channels can become exhausted and might not be visible from the outside
  • this may affect CO2 monitoring but not show visual indications of exhaustion
  • air space = 48-55% of the volume of the canister
  • some manufacturers now use polymers to bind granules in pre-formed channels to prevent channeling
20
Q

Describe Compound A formation in CO2 absorbers

A
  • created when sevoflurane is degraded by a strong base in carbon dioxide absorbents containing KOH and to a lesser extent NaOH
  • has been found to be nephrotoxic in rats
21
Q

MAC hour recommendation and compound A

A

-

22
Q

Describe Carbon Monoxide formation in CO2 absorbers

A
  • CO has been known to develop from the volatile anesthetic in desiccated NaOH and KOH containing aborbers when:
  • high flow is used through a system for a prolonged period of time
  • when the system is not in use for 24-48 hours (Monday)
  • this results in critical levels of carboxyhemoglobin
23
Q

Which anesthetic has been known to produce the highest amount of CO2

A

-Desflurane

24
Q

Which absorber is associated with fires?

A

-Baralyme

25
Q

Anesthesia Safety Foundation Recommendation on Safe Use of Carbon Dioxide Absorbents

A

1) turn off all gas flows when the machine is not in use
2) change absorbent regularly
3) change the absorbent whenever the color indicates exhaustion
4) change all the absorbents at one time if more than one
5) change absorbent when unsure of the state of hydration (if FGF has been high for a long time)
6) low flows preserve humidity in granules

26
Q

How does gas flow through the absorber on inhalation?

A

-

27
Q

How does gas flow through the absorber on exhalation?

A

-