Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
85 Cards in this Set
- Front
- Back
|
What is the semi-closed circle absorber?
|
1. Components arranged in a circle
2. FGF enters on one side and excess/waste gas exits other side 3. Unidirectional valve routes gas in one direction 4. CO2 removed from exhaled gas before the gas is returned to pt for rebreathing |
|
|
What are the components of a semi-closed circle absorber?
|
1. Inspiratory and expiratory corrugated tubing
2. Unidirctional inspiratory and expiratory valves - horizontal or vertical 3. CO2 absorber 4. Reservoir bag 5. Adjustable pressure limiting valve (APL, pop-off valve) |
|
|
What is the diameter, capacity, and resistance of corrugated tubing of the SCCA?
|
1. 22mm
2. 400-500 ml internal volume 3. Low resistance |
|
|
Is the tubing a coaxial system (inspiratory tubing inside expiratory tubing) in the SCCA and what is the significance?
|
1. Yes
2. Keeps gases warm |
|
|
How many CO2 absorbers are on the SCCA?
|
1. One or two canisters
2. Or single disposable canister |
|
|
For a reservoir bag <1.5 L, what is the pressure of the bag when quadrupled in size?
|
30-50 cmH2O
|
|
|
For a 3L bag what is the pressure of the bag when quadrupled in size?
|
35 cmH2O
|
|
|
What is the APL?
|
1. Spring loaded valve that varies the pressure in the breathing system
2. contains a check valve 3. Prevents retrograde flow |
|
|
What is the minimum opening pressure of the APL valve that allows bag to fill before check valve opens?
|
1 cmH2O
|
|
|
At inspiration on a SCCA system for SR or CR, what position is the APL valve?
|
1. Check valve closes
2. Gas flow to pt |
|
|
If the pt is spontaneously breathing what position should the APL be?
|
Fully open
|
|
|
For CPAP method, what position should the APL valve be?
|
Partially closed
|
|
|
What pressure range can the APL valve be adjusted to?
|
1-75 cmH2O
|
|
|
Where is the pressure of the circuit indicated?
|
Pressure gauge on absorber
|
|
|
What is the importance of the selector switch on the manifold of the absorber?
|
1. It has two ports
2. One to bag 3. One to ventilator |
|
|
If gas is given from the bag, what is the flow of the gas?
|
1. One-way through circuit
2. Through CO2 absorber then mixes with FGF 3. Then to pt |
|
|
How is rebreathing prevented in the SCCA?
|
1. Unidirectional valves on bothe insp. and expir. limbs
2. FGF cannot enter circle between APL and pt 3. APL cannot be located between pt and insp. valve |
|
|
How is the APL valve closed?
|
Turn clockwise
|
|
|
Does the SCCA circuit have a HEPA filter?
|
One can be placed on the exp. limb or insp. limb or both
|
|
|
What can the HEPA filter trap?
|
99.97% of particles >0.3microm
|
|
|
Is the HEPA filter effective at trapping HIV?
|
No b/c particles are 0.08micorm
|
|
|
Can the HEPA filter trap Hepatitis C?
|
No b/c particles are 0.06microm
|
|
|
Can the HEPA filter trap staph aureaus?
|
Yes b/c particles are 1.0microm
|
|
|
Can the HEPA filter be combined with a HME to provied a heat and moisture exchanger?
|
Yes
|
|
|
What are some problems with using a HEPA filter?
|
1. Can increase resistance
- esp. in peds and obstructive dz 2. Questionable efficacy in preventing post-op inf 3. No CDC recommendations regading its use |
|
|
What are the advantages of using a SCCA?
|
1. Relative constant inspired anesthetic []
2. Decrease heat and water loss 3. Decrease pollution 4. Lower FGF needs |
|
|
What are the disadvantages of using a SCCA?
|
1. Increased resistance to breathing
2. Bulky system and hard to clean 3. CO2 absorption dependent upon freshness of soda lime, gas flow, size of canisters and reservoir 4. Approx. 10 areas of potential disconnects |
|
|
Where would you want to check first if there was a disconnect?
|
The pt
|
|
|
What are the advantages to using a CO2 absorber?
|
1. Rebreathing of all gases except CO2
2. Decreases the cost of anesthetics 3. Reduced OR pollution 4. Containment of explosive/flammable anesthetics 5. Conservation of heat and humidity |
|
|
What is a base?
|
A hydroxide salt of an alkali or alkline earth metal
|
|
|
What is the rxn between CO2 + H2O?
|
H2CO3
|
|
|
What is the rxn betweem 2H2CO3 + 2NaOH+ 2 KOH?
|
Na2CO3 +K2CO3 +4H2O
|
|
|
What is the rxn between 2Ca(OH)2 + Na2CO3 + K2CO3?
|
2CaCo3 + 2NaOH + 2 KOH
|
|
|
Will the regeneration of NaOH have any affect?
|
No other than it will cause a color change of the CO2 absorber indicator when it has been exhausted
|
|
|
What is the CO2 absorber Baralyme composed of?
|
1. 80% CaOH
2. 20% BaOH |
|
|
Is Baralyme used an absorber now?
|
No b/c when dessicated extreme heat results >300 C causing a risk for fire
|
|
|
What is Amsorb CO2 absorber composed of?
|
1. 83% Ca(OH)2
2. 1% CaCl2 3. 1% CaSO4 4. 14% H2O 5. Polyvinylprrolidine |
|
|
What is Amsorb designed for?
|
Low flow anesthesia
|
|
|
Does Amsorb degradation cause CO, Compound A, or Formaldehyde production?
|
No
|
|
|
Is there a color change of the Amsorb absorbant once it is dessicated?
|
Yes
|
|
|
Is the color change of Amsorb reversible?
|
No
|
|
|
What is the Sodalime CO2 absorbant composed of?
|
1. 94% CaOH
2. 5% NaOH 3. 1% KOH 4. 14-19% H2O 5. Silica |
|
|
Why is water added to the Sodalime absorbant?
|
B/c it is dry
|
|
|
Why is silica added to the Sodalime absorbant?
|
For hardness
|
|
|
What indicators are used in various absorbants?
|
1. Ethyl violet
2. NaOH |
|
|
How does ethyl violet change the absorbant color?
|
Ethyl violet changes color with increased H+ []
|
|
|
How does NaOH change the absorbant color?
|
1. It is a strong base pH=10.3
2. It is consumed and replaced with a weaker base Ca(OH)2 3. The pH falls and the color changes from white to purple |
|
|
Will the bottom of the canister change color first?
|
No the top does
|
|
|
Is the chemical rxn of the absorbant an exothermic rxn?
|
Yes
|
|
|
How many calories are a result of this exothermic rxn of the absorbant?
|
14,000cal/gmw
|
|
|
How much CO2 is absorbed by the absorbant?
|
44 gms or 22L
|
|
|
What is the size of the granules of the absorbant?
|
1. 4-8 mesh
2. Irregular surface |
|
|
What would happen if the granules were any smaller?
|
They would become dust or clump
|
|
|
What would happen if the granules were any bigger?
|
There wouldn't be enough surface are for the CO2 to hold onto
|
|
|
What color is the absorbant initially?
|
White
|
|
|
What color is the absorbant once it is dessicated?
|
Pink or purple
|
|
|
How many canisters are present on an anesthesia machine to hold the absorbant?
|
One or two clear canisters
|
|
|
How much volume does each canister hold?
|
1000 mL
|
|
|
How much TV should the canister accommodate?
|
>one maximum TV
|
|
|
What is the significance of using baffles and screens on the canister?
|
1. To direct the flow of gas towards the center of the canister
2. If not present the gas would follow the path of least resistance and slid down sides 3. It optimizes CO2 absorption |
|
|
How much CO2 can 100 grams of absorbant neutralize before EtCO2 increases by 1%?
|
26L
|
|
|
How efficient is using a single canister compared with a double canister?
|
50%
|
|
|
How much CO2 can a single canister absorb?
|
15L
|
|
|
How effecient is the use of a double canister?
|
70%
|
|
|
How much CO2 can a double canister absorb?
|
15-20L
|
|
|
What is the significance of the degradation of Sevo by an absorbant?
|
1. Forms Compound A
2. Causes nephrotoxicity |
|
|
What causes an increase production of Compound A when using Sevo?
|
1. Low FGF
2. KOH absorbant 3. NaOH absorbant 4. Increase temp 5. Long anesthetic duration 6. Sevo [] and dessication |
|
|
Is Sodalime a high alkaline absorbant?
|
Yes, high in KOH and NaOH
|
|
|
When Sodalime is dessicated and more volatile anesthetic is run through the absorbant without changing the absorbant, what can result?
|
1. CO
2. Compound A with Sevo |
|
|
When can you see increase CO from an absorbant?
|
When you start the first case of the day on Monday when FGF has been left on accidentally over the weekend and the absorbant gets dehydrated
|
|
|
Put the volatile anesthetics in order from greatest CO production to least CO production
|
Des>Enflurane>Iso>Halothane
|
|
|
Does Sevo cause CO production?
|
Only at temps > 80 C
|
|
|
How can you prevent CO production?
|
1. Turn off all gases at end of case
2. Turn off machine at end of the day 3. Use auxillary flowmeter for nasal/mask O2 4. Flush machines with 100% O2 on Monday mornings before the start of a case |
|
|
Are absorbants irritating to the skin and mucous membranes?
|
Yes b/c they are strong bases
|
|
|
What is a closed system?
|
1. No access to atmosphere
2. Complete rebreathing of exhaled gases |
|
|
What are the advantages of using a closed system?
|
1. Low FGF
2. Minimum room pollution 3. Excellent heat and water conservation 4. Significant cost savings by using low FGF 5. Decrease risk of barotraumas by using low FGF 6. Decrease resistance to breathing by using low FGF |
|
|
What are the disadvantages of using a closed system?
|
1. Greater risk of hypoxia and CO2 retention
2. Rapid change in depth of anesthesia not possible 3. Accumulation of CO from smokers at low FGF 4. Compound A formation at low FGF |
|
|
How can you off-set the problem of not being able to rapidly change the depth of anesthesia using a closed system method?
|
1. Induce with a semi-open system
2. Then close 3. Then semi-open again on emergence so pt doesn't take as long to wake up |
|
|
On a closed circle system, is the APL fully open?
|
No, fully closed
|
|
|
What is the FGF volume of a closed system?
|
500-600 mL/min
|
|
|
What is the volume neccessary to meet minimum O2 requirements and replace anesthetic loss to uptake?
|
150-500 mL
|
|
|
Should low FGF be used in a closed system?
|
1. Yes
2. FGF<MV 3. 0.5-2 LPM |
|
|
What is the gas flow adjusted to in a closed system?
|
1. So reservoir bag refills (SR)
2. Or bellows reach bellows stop at end expiration |
|
|
What FGF rate does the FDA reccommend when using Sevo?
|
1. 1 LPM
2. <2 MAC hours |
|
|
What should you check for the presence of and function of as part of the daily machine checkout?
|
AMBU BAG!!!
|
