Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

principles of anesthesia i > Breathing Systems II (Exam II) > Flashcards

Breathing Systems II (Exam II) Flashcards

1
Q

What are the components of a Mapleson circuit?

A
  • Reservoir bag
  • Corrugated tubing
  • APL valve
  • Fresh gas inlet
  • Patient connection

Not all have a reservoir bag or corrugated tubing

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

What components are missing from a Mapleson circuit?

A
  • CO₂ absorber
  • Unidirectional valve
  • Separate Insp & Exp limbs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the two other names for Mapleson circuits?

A
  • CO₂ washout circuit
  • Flow-controlled breathing system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What system has the best efficiency for spontaneous ventilation?

A

Mapleson A (Magill’s system)

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

Which system has the worst efficiency for controlled ventilation?

A

Mapleson A (Magill’s system)

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

Describe the Mapleson A (Magill’s system)

A
  • FGF enters near the reservoir bag
  • APL is near the patient
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Rebreathing with a Mapleson A during a controlled ventilation will occurs unless _ _ _?

A

FGF is very high (>20 L/min)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How is rebreathing prevented during spontaneous ventilation with a Magill’s system?

A

FGF must be greater than (or equal to) minute volume.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the Mapleson B

A
  • APL and FGF near the patient
  • Reservoir bag at the end of the system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

FGF should be 2x minute volume during spontaneous and controlled ventilation to prevent rebreathing in a Mapleson _________ circuit.

A

B
System is obsolete

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

What makes the Mapleson B inefficient?

A

Much of the FGF is vented through the APL during exhalation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does the Mapleson C differ from the Mapleson B circuit?

A
  • Identical to Mapleson B, without the corrugated tubing

Almost as efficient as Mapleson A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What circuit is used for emergency resuscitation?

A

Mapleson C

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

What FGF characterizes the Mapleson C?

A

2x minute volume

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

Describe the Mapleson D circuit.

A
  • 3-way T-piece: pt connection, FG inlet, corrugated tubing
  • Reservoir at the end, APL near reservoir, FG inlet near pt
  • PEEP valves may be added
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What breathing circuit is the most efficient for controlled ventilation?

A

Mapleson D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What FGF characterizes the Mapleson D circuit?

A

2-2.5x minute ventilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the Bain modification (Coaxial)?
What breathing circuit is it used on?

A
  • Inspiratory gas targeted through an inner tube.
  • Expiratory gases exhaled into the outer corrugated tubing.

Used on a Mapleson D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which circuit has no reservoir bag or APL valve?

No capability to ventilate the patient manually

A

Mapleson E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which circuit is used in spontaneously breathing patients to deliver O₂ ?

A

Mapleson E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is another name for a Mapleson E circuit?

A

Ayre’s T-piece

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

When would you most likely see a Mapleson E circuit?

A
  • Pediatric cases
  • Transport to the floor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What would be the only way to do controlled ventilation with a Mapleson E circuit?

A

By pinching the open end on inspiration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

A Jackson Rees is a modified ___________ circuit, where a reservoir bag is added to the circuit.

A

Mapleson E + Reservoir bag = Mapleson F (Jackson Rees)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the FGF for a Mapleson F circuit?

A

2-2.5x minute ventilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How is excessive pressure prevented with a Mapleson F circuit?

A

No APL valve present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

List all the Mapleson Circuits in terms of most efficient to least efficient for spontaneous ventilation.

A

A > DFE > CB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

List all the Mapleson Circuits in terms of most efficient to least efficient for controlled ventilation.

A

DFE > CB > A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the advantages of Mapleson Circuits?

A
  • Simple, inexpensive, lightweight
  • Changes in FGF composition result in rapid changes in circuit
  • Low resistance to gas flow
  • No toxic products d/t CO₂ absorbent
  • No degradation of VA’s
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the disadvantages of Mapleson circuits?

A
  • Require high FGF
  • Can’t conserve heat & humidity
  • Scavenging difficult (except for Mapleson D)
  • Not suitable for MH pts (can’t increase FGF to remove CO₂)
31
Q

Extent of rebreathing and conservation of exhaled gases in a circle system depends on _____.

A

FGF

32
Q

In a circle system, higher FGF = less _________ and more ______ ____.

A

rebreathing
waste gas

33
Q

How is rebreathing prevented in a circle system?

A
  • Unidirectional valves located between patient & reservoir bag (on insp & exp limbs)
  • FG inflow cannot enter circuit between exp valve & patient
  • APL valve cannot be located between patient & inspiratory valve.
34
Q

What characteristics define a semi-closed circle system?
(Contemporary systems)

A
  • Low-flow anesthesia
  • FGF < minute ventilation
  • 50% of expired gas is rebreathed after CO₂ removal
    (Partial rebreathing occurs but some waste flow is vented through APL or waste gas valve of ventilator)
35
Q

In what patients would a semi-open circle system be used?
Why?

A
  • post-op & ICU vents, scuba
    Higher FGF w/ minimal rebreathing and more venting of waste gases.
    (Non-rebreathing systems)
36
Q

What are the characteristics of a closed circle system?

A
  • Complete rebreathing
  • No waste gas vented
  • O₂ inflow matches metabolic demand
  • Ex. Low- and Minimal flow anesthesia
  • VAs are added in precise amounts via liquid or vaporizer
37
Q

What are the advantages of Low-flow anesthesia?

A
  • Decreased VA usage
  • Better temp & humidity control
  • Reduced environmental pollution
38
Q

What are the disadvantages of low-flow anesthesia?

A
  • Difficulty adjusting depth quickly
  • Possible accumulation of gases (CO, acetone, methane, etc)
  • VA degradation by-products (CO, Compound A)
39
Q

What are the advantages of a circle system?

A
  • Low FGF can be used
  • CO₂ elimination
  • Conserves heat/moisture/gases.
  • OR pollution prevention
  • Stable inspired gas concentration
40
Q

What are the disadvantages to a circle system?

A
  • Complex design
  • CO or compound A
  • Compromised VT during controlled ventilation
41
Q

What is the most prevalent problem with Circle systems?

A

Misconnection/Disconnections

42
Q

What are the components of Self-Inflating Manual Resuscitators (Ambu)?

A
  • Self-expanding bag
  • T-shaped non-rebreathing valve
  • Bag inlet valve
  • Pop-off valve
  • Excess oxygen venting valve
  • Oxygen reservoir
43
Q

In what scenarios would you need a self-inflating manual resuscitator?

A
  • Pt transport
  • CPR
  • Emergency backup
  • Hand ventilation in absence of O₂ or medical air
44
Q

What are hazards associated with self-inflating manual resuscitators?

A
  • Barotrauma
  • Gastric insufflation
  • Large variation in VT, PIP, and PEEP
  • Non-rebreathing valves generate resistance
45
Q

Bacterial filters are used in what three scenarios discussed in lecture?

A
  • M. Tuberculosis
  • COVID
  • PUI
46
Q

Where are bacterial filters placed on the breathing system?

A

Expiratory limb

47
Q

What are the two size types of bacterial filters?

A
  • Small pore (↑ resistance, pleated for ↑ surface area)
  • Large pore ( ↓ resistance, smaller surface area)
48
Q

What are the two types of bacterial filters?

A
  • Hydrophobic
  • Combination (Filter + HME)
49
Q

What are the characteristics of a hydrophobic filter?

A
  • Prevents water penetration
  • Increased resistance
  • Decreased efficiency
50
Q

Where would a combination bacterial filter (filter + HME) be placed?

A

At the Y-piece (inspiratory and expiratory barrier)

Inspiratory & Expiratory barrier

51
Q

What are some of the complications of bacterial filters?

A
  • Obstruction (sputum, edema fluid, etc)
  • Leakage (housing of gas line)
52
Q

Suggested Breathing System Filter Placement Diagram

A
53
Q

Describe Humidity

A

Amount of water vapor in a gas

54
Q

What is absolute humidity?

A

Mass of water vapor present in gas in mg H2O/L

55
Q

What is relative humidity?

A

Percent saturation; amount of water vapor at a particular temperature

56
Q

What is water vapor pressure?

A

Pressure exerted by water vapor in a gas mixture

57
Q

At what point in the airway is heating and humidification of air complete?

A

Mid-Trachea
34°C with an absolute humidity of 34 to 38 mg/L (95% to 100% relative humidity)

58
Q

Absolute humidity occurs at _____ mg/L (100% relative humidity).

A

44 mg/L

59
Q

What results with low ambient temperatures?

A
  • Little capacity to hold water vapor
  • Low absolute humidity
  • Upper airway transfers large amounts of heat and moisture
60
Q

What results with warm ambient temperatures?

A

Little heat energy is expended to warm inspired gases

61
Q

Cool inspired gas can trigger _.

A

Bronchospasms

62
Q

What can occur with underhumidification of air?

A
  • Resp Tract damage (secretions thicken, ciliary function inhibited, surfactant activity inhibited, mucosa susceptible to injury)
  • Body heat loss
  • Tracheal tube obstruction (thickened secretions)
63
Q

What occurs with over-humidification?

A
  • Condensation of water in the airway
  • Reduced mucosal viscosity (rx of water intoxication)
  • Inefficient mucocilliary transport
  • Airway resistance, risk of pulm infection, surfactant dilution, atelectasis, and V/Q mismatch
  • Obstruction of sensors
64
Q

What are HMEs?
Where are they placed?

A
  • Heat and moisture exchanger
    (Aim to reproduce more normal physiologic conditions in the lower respiratory tract)
  • Placed between Y-piece and proximal end of ETT
65
Q

What are some disadvantages with use of an HME?

A
  • Lower EtCO₂ reading
  • ↑ resistance & circuit dead space
  • Reduced efficiency w/ large VT (hydrophobic models)
66
Q

Where would you place an EtCO2 monitor if using an HME?

A

Proximal (before) to the HME

67
Q

Hygroscopic HMEs are more efficient at _.

A

retaining heat and moisture

68
Q

Hydrophobic HMEs are more efficient at _

A

Filtering pathogens

69
Q

What are humidifiers?
What populations benefit most from their use?

A
  • Devices used to increase the humidity in O2 supplied to pts
  • Neonates, pts with difficult respiratory secretions, or hypothermic pts
70
Q

In what 4 ways do humidifiers work?

A
  • Bubble or cascade (active)
  • Pass-over
  • Counter-flow
  • In-line
71
Q

Are humidifiers heated or unheated?
Where are they placed?

A
  • Can be both
  • Placed on the inspiratory limb
72
Q

What two considerations should be in mind with humidifier use?

A
  • Condensation can decrease delivered VT
  • Water trapping-change frequently to decrease risk of contamination and infection
73
Q

What are the advantages of active humidifiers?

A
  • Can deliver gas at body temp or even higher
  • More effective than HME’s
74
Q

What are the disadvantages of active humidifiers?

A
  • Bulky
  • Contamination (hard to clean)
  • Expensive (compared to HME)
  • Electrical problems/ thermal injury potential
  • Water aspiration risk

principles of anesthesia i (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions