Brainscape's Knowledge GenomeTM

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


See full index

KDH: Principles (EXAM 2) > Exam 2 Breathing Systems: Part 2 (6/24/24) > Flashcards

Exam 2 Breathing Systems: Part 2 (6/24/24) Flashcards

1
Q

Why are Mapleson Circuits thought to be mostly obsolete?

A

They do not have a CO2 absorber

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

Components of Mapleson Circuits:

A
  • Reservoir Bag (Not all of them)
  • Corrugated Tubing (Not all of them)
  • APL Valve (Not all of them)
  • Fresh Gas Inlet
  • Patient Connection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is missing in the Mapleson Circuits? (3)

A

CO2 Absorbers
Unidirectional valves
Seperate inspiratory/expiratory limbs

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

What determines how much rebreathing occurs in the Mapleson Circuits?

A

Fresh Gas Flow

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

How would we know if CO2 is being rebreathed while using a Mapleson Circuit?

A

Monitor ETCO2

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

Location of FGF entrance and APL valve in a Mapleson A (Magill’s System)?

A

FGF enters near reservoir bag (opposite of the pt.)

APL is near the pt.

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

In regard to efficiency, what kind of ventilation is the Mapleson A circuit the best and worst at?

A

Best: Spontaneous
Worst: Controlled

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

Rebreathing will occur while using a Mapleson A during controlled ventilation unless the patient’s FGF minute ventilation is greater than ___.

A

> 20 L/min

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

Location of APL valve, FGF inlet and reservoir bag in a Mapleson B?

A

APL anf FGF inlet are near pt
Reservoir Bag is at the end of the system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The Mapleson C is almost identical to the Mapleson B, but the ____ is omitted.

A

Corrugated Tubing

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

Compare the efficiency of the Mapleson C to Mapleson A with spontaneous ventilation:
How does the expiratory pause change the efficiency?

A

Mapleson C is almost as efficient as Mapleson A.

If expiratory pause is longer, this circuit becomes less efficient

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

The Mapleson C closely resembles a ___.

A

Ambu Bag

Used for emergency resuscitation

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

Location of the Reservoir Bag, APL and FGF inlet in a Mapleson D?

A

Reservoir at the end
APL near reservoir
FGF inlet near pt.

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

This Mapleson circuit does not have a reservoir bag or an APL valve:

A

Mapleson E (Ayre’s T-Piece)

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

The Mapleson E circuit is preferred in this population:
Why?

A

Preferred in Pediatrics:
There is a decreased amount of resistance

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

What is the modification made to the Mapleson E that makes it a Mapleson F (Jackson Rees)?

A

Addition of a Reservoir bag with a hole at the end

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

Select the 2 correct systems:

Significant amounts of fresh gas is vented through pop-off at end expiration :

Mapleson A
Mapleson B
Mapleson C
Mapleson D
Mapleson E
Mapleson F

A

Mapleson B
Mapleson C

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

Select the 3 correct systems:

FGF drives exhaled alveolar gas away from pt:

Mapleson A
Mapleson B
Mapleson C
Mapleson D
Mapleson E
Mapleson F

A

Mapleson D
Mapleson E
Mapleson F

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

Rank the efficiency of the Mapleson Circuits from Most efficient to least efficient for spontaneous ventilation:

A
  1. Mapleson A
  2. Mapleson D, F, E
  3. Mapleson C, B
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Rank the Mapleson circuits from most efficient to least efficient for controlled ventilation:

A
  1. Mapleson D, F, E
  2. Mapleson C, B
  3. Mapleson A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which Mapleson circuit is termed “Obsolete”?

A

Mapleson B

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

This Mapleson Circuit is the most efficient system for controlled Ventilation:

A

Mapleson D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

This Mapleson circuit is used in spontaneously breathing pts to deliver O2:

A

Mapleson E

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

Advantages of Mapleson Circuits:

A
  • Simple, inexpensive, and lightweight
  • Changes in FGF composition result in rapid changes in the circuit
  • Low resistance to gas flow
  • No toxic products d/t lack of CO2 absorbent
  • No degradation w/ Volatiles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

A couple disadvantages to using Mapleson circuits is that they require ___ and are not suitable for patients with ___.

A

Require high FGF

Not suitable for Malignant Hyperthermia patients

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

All of the Mapleson circuits have a challenge with scavenging except for ___.

A

Mapleson D

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

Rules to prevent rebreathing in a Circle System

Where must the unidirectional valves be located on both the inspiratory and expiratory limbs?

A

Between the patient and the reservoir bag

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

Rules to prevent rebreathing in a Circle System

Where must the Fresh gas flow inlet NOT enter the circuit at?

A

Between the patient and the Expiratory Valve

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

Rules to prevent rebreathing in a Circle System

True or False:

The APL valve must be located between the pt and the inspiratory valve

A

False:

APL valve cannot be located between the pt and the inspiratory valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

In a circle system these 2 things are dependent upon the Fresh Gas Flow:

A

The extent of rebreathing
Conservation of exhaled gases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Describe the function of a circle system in a “Semi-Closed” circuit:

A

“Contemporary system”

Partial rebreathing occurs but some waste flow is vented through APL or waste gas valve of ventilator

(Semi-wasted/Semi-rebreathed.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Example of a semi-closed circuit for a circle system: (Type of Anesthesia)
What does this mean? (2)

A

Low Flow Anesthesia:

  • FGF is less than Minute ventilation
  • 50% of expired gas is rebreathed after CO2 removal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Describe the function of a circle system in a “Semi-Open” circuit: (3)

A

Non-rebreathing systems

Higher FGF with minimal rebreathing and more venting of waste gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Examples of semi-open circuits for a circle system: (3)

A
  • Post-Op/ICU Vents
  • Scuba Gear
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Things to remember about a “Closed” circle system: (5)

A
  • Use of Low/minimal Flows
  • Complete rebreathing
  • No waste gas is vented out
  • Obsolete
  • Rate of oxygen inflow matches patient’s metabolic demand (dropper method)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Advantages to low flow anesthesia:

A
  • Decreased use of VAs
  • Improved temperature and humidity control
  • Reduced environmental pollution

Low-Flow =
1. Lower VA, 2. Lower heat loss 3. Lower Pollution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Disadvantages to low flow anesthesia:

A
  • Difficulty in rapidly adjusting anesthetic depth
  • Possibility of accumulating unwanted exhaled gases ( ex: CO, acetone, methane)
  • VA degradation by-products (ex: CO, compound A)
38
Q

Advantages of Circle Systems: (5)

A
  • Low FGF can be used (and High FGF).
  • Elimination of CO2 (Scrubber + APL + Scavenging System)
  • Relatively stable inspired gas concentration (Gases are dialed in)
  • Conservation of moisture/heat/gases (circle so humidity is maintained)
  • Prevention of OR pollution (not open to environment)
39
Q

Disadvantages of Circle Systems: (4)

A
  • Complex design
  • CO or compound A
  • May compromise Vt during controlled ventilation (D/t Corrugated tubing distinction)
  • ASA Closed Claims Project
40
Q

The number 1 problem (according to the ASA Closed claims project) associated with use of a circle system had to do with ___.

A

Misconnections or disconnections

41
Q

Components of Self-Inflating Manual Resuscitators or “Ambu-bags”: (6)

A
  • Self-expanding Bag
  • T-shaped non-rebreathing Valve
  • Bag Inlet Valve
  • Pop-off valve
  • Excess oxygen venting valve
  • Oxygen reservoir

BOPETS

42
Q

Important uses of Self-Inflating Manual Resuscitators: (4)

A
  • CPR
  • Transport
  • Hand ventilation in the absence of an oxygen or air source
  • Emergency Back-Up
43
Q

Hazards associated with the use of Self-Inflating Manual Resuscitators: (3)

A
  • Barotrauma or gastric insufflation
  • Significant variation of tidal volume, PIP, and PEEP
  • Nonrebreathing valves generate resistance
44
Q

Bacterial Filters are effective at preventing what?
Where should they be placed?

A

Effective at preventing contamination of the anesthesia machine from airborne diseases (TB, Covid, PUI)

Placed on the Expiratory Limb

45
Q

What does PUI stand for?

A

Person Under Investigation

46
Q

Different types of Bacterial Filters discussed in lecture: (4+1)

A
  • Small-pore compact Matrix
  • Larger pore arrangement; Less Dense
  • Hydrophobic
  • Combination (Filter + HME)

Permanent electrical polarity; Designed to enhance VanderWaals forces that hold organisms in the matrix.

47
Q

Describe the small-pore compact matrix:

A
  • High Airflow resistance
  • Pleated = creates a larger surface area
48
Q

Compared to the small-pore compact matrix the larger, less dense pore arrangement has _____ and ____.

A

Less resistance & Smaller surface area

49
Q

Hydrophobic Bacterial Filters prevent___. They have _____ resistance and _____ efficiency.

A

Prevent water penetration

Increased Resistance

Decreased efficiency

50
Q

Where should the Combination bacterial filter be placed?

A

At the Y-Piece

51
Q

What is one thing that can happen that would decrease the efficiency and increase the resistance in any and all of these bacterial filters?

A

Accumulation/condensation of water, secretions, blood or any liquid.

52
Q

4 things that can obstruct a bacterial filter:

A
  1. Sputum
  2. Edema Fluid
  3. Nebulized aerosols
  4. Malpositioning
53
Q

Per the APSF recommendations, what is the best location for the bacterial filters to be placed?

A

The Expiratory Limb

54
Q

What is the ONLY time that placement of the bacterial filter on the inspiratory limb is warranted?

A

Only recommended when the machine may have been contaminated by a previous patient.

55
Q

For Covid positive patients or PUI patient’s placement of an ____ is recommended, but is optional for all others.

A

Airway Filter

56
Q

Definitions:

Amount of water vapor in a gas:

57
Q

Definitions

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

A

Absolute Humidity

58
Q

Definitions

Percent saturation; amount of water vapor at a particular temp:

A

Relative Humidity

59
Q

Definitions

Pressure exerted by water vapor in a gas mixture:

A

Water Vapor Pressure

60
Q

Usually, by this point heating and humidification has occurred.

A

Mid-Trachea

61
Q

A temperature of 34 degrees C, with an absolute humidity of 34-38 mg/L corresponds to what relative humidity?

A

95%-100% relative humidity

62
Q

An absolute humidity of ___ corresponds to 100% relative humidity.
At what degree C does this also correspond to?
What is this called?

A

44 mg/L

37 degrees C

Isothermic Saturation Boundary

63
Q

At what anatomical landmark is 100% relative humidity reached?

A

At the carina

64
Q

What can cool inspired gas possibly trigger?

A

Bronchospasm

Asthmatics are more likely to have bronchospasm in the Winter.

65
Q

Under-humidification can cause these 3 issues:

A
  1. Damage to Respiratory Tract (Drying out)
  2. Body Heat Loss
  3. Tracheal Tube Obstruction (ICU: adding liquid to thin out secretions to improve suctioning..)
66
Q

What specific respiratory tract issues can arise with under-humidified inspired gas? (4)

A
  • Thick Secretions
  • Decreased Ciliary Function
  • Impaired surfactant activity
  • Mucosa is susceptible to injury
67
Q

Over-humidification is caused ____ in the airway.

A

Condensation of Water

68
Q

Complications associated with over-humidification (4)

A
  • Reduced mucosal viscosity and risk of water intoxication
  • Inefficient mucociliary transport
  • Airway resistance, risk of pulmonary infection, surfactant dilution, atelectasis, and V/Q mismatch
  • Obstruction to sensors
69
Q

What do humidification devices aim to do?

A

To reproduce more normal physiologic conditions in the lower respiratory tract

70
Q

Functions of an HME:

A
  • Conserves some exhaled heat and water and returns them to the pt
  • Bacterial/viral filtration and prevention of inhalation of small particles (HMEF)
  • Disposable with exchange medium enclosed in plastic housing
71
Q

Location of the HME:

A

Placed close to the pt, between Y piece and proximal end of ETT or LMA

72
Q

Disadvantages to HME use:

A
  • Low ETCO2 reading (if ETCO2 is placed after the HME)
  • Increases resistance and dead space in circuit
  • Efficiency may be reduced with large Vt (unable to humidify larger Vt as efficiently).

Especially in Hydrophobic models (filters?)

73
Q

This type of HME absorbs water in exhalation and release it in inspiration:

A

Hygroscopic

74
Q

This type of HME has a pleated hydrophobic membrane with small pores:

A

Hydrophobic

75
Q

This type of HME is a more efficient filter of pathogens

A

Hydrophobic

76
Q

This type of HME is the most efficient at retaining heat and moisture.

A

Hygroscopic

77
Q

In which patient population is the use of a humidifier important? (3)

A

Neonates, pts with difficult respiratory secretions, or hypothermic pts.

78
Q

Various Ways in which humidifiers can pass a stream of gas:

A
  • Bubble or cascade
  • Pass-over
  • Counter-flow
  • Inline
79
Q

Where should humidifiers be placed?
Where should they definitely NOT be placed?

A

Placed in inspiratory limb downstream of unidirectional valve
Heated humidifiers should not be placed in expiratory limb

80
Q

Condensation in the humidifier can decrease ___?

A

Delivered Tidal Volume

81
Q

These need to be changed frequently to decrease risk of contamination and infection.

A

Water Traps

82
Q

Advantages to Humidifier use:

A
  • Can deliver saturated gas at body temp or higher
  • More effective than HME
83
Q

Disadvantages to Humidifier use: (5)

A
  • Bulky
  • Potential electrical malfunction and/or thermal injury
  • Contamination, cleaning issues
  • Higher cost than HME
  • Water aspiration risk
84
Q

Why do we get ETCO2 during esophageal intubation?

A

Gastric insufflation with Ambubag

85
Q

What are 2 categorical complications that can occur with bacterial filters?

A

Obstruction
Leakage - at housing/in line filter.

86
Q

What is our natural HME?

A

Nasal Cavity - maximal contact of inspired gas with large mucosal surface area.

87
Q

At mid-trachea what is the expected temperature, absolute humidity, and relative humidity?

A

Temp: 34
Absolute Humidity: 34-38mg/L
Relative Humidity: 95-100%

88
Q

What is isothermic saturation boundary?

A

Absolute Humidity 44mg/L
Relative Humidity. 100%
Location: at the Carina.

89
Q

What is estimated body temperature or the temp of inhaled air at isothermic saturation?

90
Q

Cold Ambient Temperatures such as in the OR have what capacity to hold water vapor/absolute humidity?

A
  1. Little capacity to hold water vapor
  2. Low absolute humidity
91
Q

What are 4 ways that underhumidification can cause damage to the respiratory tract?

A
  1. Secretions thicken
  2. Ciliary function decreases
  3. Surfactant activity is impaired.
  4. Mucosa susceptible to injury (Dried out)
92
Q

HME are _____ , and can be modified to have a _______; While Heated humidifiers are ____.

A

(Heat and Moisture exchanger) are PASSIVE
FILTER

Heated Humidifiers are ACTIVE

KDH: Principles (EXAM 2) (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions