Brainscape's Knowledge GenomeTM

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


See full index

Interventions 1 (RESP 266) > Mod 5 Vent Variables > Flashcards

Mod 5 Vent Variables Flashcards

1
Q

how do you determine if you match a patients O2 needs/requirements?

A

Good CNS function

good perfusion

etc. indeterminable without a mixed venous pressure/sample to get a better idea at the hemoglobin

i.e good LOC

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

What are the Vent. Mode basics?

A

volume control

Pressure control

pressure support

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

which pressure is maintain in all vent. modes?

A

PEEP (range 4-6;but set 5)

Keeps interalveolar airways open

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

What is oxygenation and ventilation controlled with?

A

Oxygenation: FiO2 and MAP
(hypoxic)

Ventilation: RR
(acidotic)

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

Vital capacity is a good measure of what?

A

our ability to cough (and help clear secretions

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

What is the purpose of ventilation?

A

-Supporting/manipulating gas exchange:

-Increase lung volume

-Reduce/manipulate WOB

-Minimize cardiovascular impairment

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

What are 2 types of respiratory failure?

A

Hypoxemic respiratory failure

Hypecapnic respiratory failure

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

What value is affected to be classified as hypoxemic respiratory failure?

A

PaO2 < 60mmHg on room air.

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

What values change to be classified as Hypercapnic respiratory failure?

A

PaCO2 > 45 mmHg

pH < 7.35

Also known as respiratory acidosis

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

when hypoxemic respiratory failure results in a normal (A-a) gradient; what is the usual cause?

A

decreased PiO2 or Hypoventilation

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

An increased (A-a) gradient will result when the hypoxemia is due to which defects/conditions?

A

True shunt

V/Q mismatch

Diffusion defects

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

What are classic indications for mechanical ventilation? (4)

A
  1. Apnea
  2. Acute ventilatory failure
  3. Impending ventilatory failure
  4. Severe refractory hypoxemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are signs of impending ventilatory failure?

A

WOB

Muscle strength and lung expansion critical numbers

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

What are common causes of hypoxemic failure?

A

V/Q mismatch

shunt

alveolar hypoventilation

diffusion impairment

decreased inspired FiO2

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

Causes of Apnea

A

Arrests

sedation (o.d)

paralytic drugs

high c-spine injury

head injury/trauma

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

Signs of impending vent. failure?

A

air hunger

tachypneic

diaphoretic

WOB

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

Neuromuscular failure

A

guilluain-barre

MS

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

refractory failure can be inferred by what factors?

A

an increase in PaO2 of less than 10mmHg after an FiO2 increase of 0.20 (or more)

OR

PaO2 < 60 of an FiO2 of > 0.40

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

slide 7 (mod 5 - A)

edit

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

Critical numbers indicating inadequate alveolar ventilation

(i.e needs mech. ventilation)

A

PaCO2 > 55mmHg

pH < 7.25 (or 7.20)

BOTH must be met to indicate mechanical ventilatory support.

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

mechanisms for increased PaCO2 when there is inadequate alveolar ventilation.

A

Increased deadspace

Increased CO2 production

Decreased alveolar ventilation (Va)

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

Critical numbers indicating inadequate lung expansion

(i.e needs mech. ventilation)

A

Tidal volume < 5 mL/kg

Respiratory rate > 35 bpm

Vital capacity < 10 mL/kg

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

Small volumes result in inadequate lung expansion; what are they complications and predicted outcomes if this is the case?

A

Complications: atelecasis and impaired gas exchange

result in increased RR to maintain Ve (minute ventilation)

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

Higher respiratory rates correspond to what?

A

lower volumes.

Can lead to respiratory muscle fatigue

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

what is vital capacity?

A

The volume of air exhaled after a maximal inspiration

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

why is vital capacity a important value when determining whether or not a patient needs mechanical ventilation?

A

Vital capacity indicates both muscle strength and lung expansion ability;

TLDR; reflects the ability to cough and clear the airway.

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

How much vital capacity is needed for an adequate cough?

A

2 x tidal volume (Vt)

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

How do you measure vital capacity?

A

typically with a wrights (turbine) or bedside spirometer.

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

which patients would test vital capacity for?

A

those with progressive muscle weakness.

(ALS, GBS, MG etc.)

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

Critical numbers that indicate inadequate muscle strength

(i.e needs mech. ventilation)

A

-Max inspiratory pressure (MIP) greater than or equal to -20 cmH2O

-Max expiratory pressure (MEP) less than 40 cmH2O

-vital capacity < 10 mL/kg

-max voluntary ventilation < (2 x Ve)

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

Normal tidal volume?

A

5 - 8 mL/kg

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

Normal vital capacity?

A

65 - 75 mL/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Normal max inspiratory pressure (MIP)

what is it a measure of?

A

-80 to -100 cmH2O

Measures patients muscle strength

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

How do you measure max inspiratory pressure (MIP)?

who would it be done for?

A

Uses nose plugs; a pressure gauge, and a one-way valve that allows for exhalation only.

patients with progressive neuromuscular disorders
(i.e MG, GBS, ALS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Normal Max expiratory pressure (MEP)

A

Normal > 100cmH2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

How do you calculate minute ventilation (MV) and what is a normal range?

A

MV = RR x Vt

Normal = 5-6 lpm

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

Critical value for WOB

(i.e needs mech. ventilation)

A

Minute ventilation [MV (or Ve)] > 10 LPM

Deadspace to tidal volume ratio (Vd/Vt) > 0.60

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what are complications with minute ventilation in relation to WOB?

edit

A

Ve needed to maintain a stable PaCO2 may become so high that it can’t be reached by the patient.

at > 10 LPM; increased probability of respriatory failure developing 2 degrees to muscle fatigue

39
Q

Normal deadspace to tidal volume ratio (Vd/Vt)

A

0.25 - 0.40 (25 - 40 %)

40
Q

It takes work to move the air in and out of deadspace.

Why does Deadspace increases WOB

A

to maintain alveolar ventilation; which is also increased

41
Q

For a given PaCO2, what variables increase/decrease to maintain PaCO2?

A

Deadspace (Vd) and minute ventilation (Ve)

42
Q

M5 slide 17 (left off)

edit

A
43
Q

What is continuous mandatory ventilation (CMV)?

A

Every breath is controlled by the ventilator
-may be vent. initiated (mandatory)
-may be patient initiated (assisted)
-vent. does all the WOB after initiated.

FULL vent. support.

44
Q

Define intermittent mandatory ventilation (IMV)

A

Goal is to only deliver set # of mandatory breaths
-all breaths delivered above set rate are spontaneous

45
Q

what is continuous spontaneous ventilation (CSV)?

A

breaths may be supported or unsupported by the ventilator

46
Q

What is the main difference in trigger variable for assisted vs. mandatory breaths?

A

Assisted breath: patient begins inspiration but the ventilator controls inspiratory phase and ends inspiration.

Mandatory breaths are triggered only by time.

47
Q

What are spontaneous breaths?

A

breaths that are triggered and cycled by the patient.

it can be supported or non supported

48
Q

Non-supported spontaneous breaths: can be defined as?

A

Breaths that are triggered, limited, and cycled by the patient (vent does nothing)

The vent controls the baseline only; all phases except the baseline are controlled by the patient

49
Q

Define supported spontaneous breaths

A

Breaths that are triggered and cycled by the patient, but limit and baseline are controlled by the vent.

Amount of Vent support determines WOB the patient must do

50
Q

Ventilators: control system - phase variables

A

Triggers: Time, Flow, Pressure

Limit: Pressure, Volume, Flow

Cycle: pressure, volume, flow, time

Baseline

51
Q

Ventilators: What is a Time triggered variable?

A

Controlled or mandatory breaths.

Breath is delivered after an amount of time has passed.
-breath is mandatory because vents start it.

need a RR to get a time trigger

52
Q

Ventilators : A/C refers to what?

A

breaths are either assisted or controlled.
-patient triggered or time triggered.

53
Q

What is an advantage of assist/control (CMV) ventilation?

A

If patient doesn’t trigger the breath, there is backup of time triggered breaths.

54
Q

Ventilators: What does max sensitivity mean?

A

Ease for patient to trigger a breath.

55
Q

Ventilators :What is a limit variable?

A

a variable that can reach/maintain a parameter before inspiration ends but does not terminate inspiration

56
Q

What are the 3 limit variables for Ventilators?

A

Pressure

Volume

Flow

57
Q

Ventilators: 2 ways to Pressure limit inspiration?

A
58
Q

When looking at a Ventilator, what are the 3 graphs displaying?

A

In descending order:

Pressure (cmH2O)

Flow (L/m)

Volume (mL)

59
Q

What is PEEP?

A

Positive End-Expiratory Pressure:

Keeps airway pressure above atmospheric throughout breathing cycle.

60
Q

What are the advantages of PEEP?

A

PEEP maintains a patients FRC and can help improve oxygenation.

-referred to as CPAP when using w/spontaneous breathes

61
Q

What is VC-CMV?

What is the Trigger, limit, cycle, and baseline?

edit

add slide 56

A

Volume controlled; continuous mechanical ventilation

62
Q

How could you go about increasing lung volumes on a ventilator?

A

End-inspiration

End-expiration

FRC

63
Q

What affects can mechanical ventilation have on cardiac function?

A

Can reduce myocardial demand secondary to hypoxemia and increased WOB

64
Q

what factors increase PIP?

A

Anything that increases Pr or Pc

65
Q

Does Pplat have a direct or indirect relationship with Volume & PEEP?

A

Direct

66
Q

Does Pplat have a direct or indirect relationship with compliance?

A

Inverse

67
Q

Variable relationships:
If you have [I] time and Vt; what can you calculate?

A

Flow

[I]time = Vt / Flow (Litres per second)

68
Q

Variable relationships:
What variable does RR affect?

A

Expiration time;

Explanation:
TCT = 60/RR –> TCT = I + E

TCT = Time cycled between breaths

69
Q

What is Flow?

A

How fast gas/fluids are moving

Measurement:
Liters per minute

70
Q

Positive airway devices: how do you increase pressure?

A

Increase flow = Increase pressure

71
Q

What happens to CO2 when RR increases?

A

It decreases; you blow off CO2

72
Q

When would you not want to increase RR given a high CO2?

A

When pH is still normal; Pt could have a abnormal normal

chronic condition; i.e emphysema or COPD are compensated by HCO3 so its normal.

73
Q

In volume control; how would you decrease inspiratory time?

A

Increasing flow; air is delivered faster.

74
Q

Will a decreased PiO2 result in a decreased or increased [A-a] gradient?

A

normal A-a

75
Q

When would hypoxemic resp. failure result in a normal A-a gradient?

A

When it is due to a decreased PiO2 and Hypoventilation

76
Q

Hypoxemic resp. failure will result in a high or low PaO2?

A

Low

77
Q

Hypoxemic resp. failure will result in a high or low PaCO3?q

A

Normal to Low

78
Q

Hypoxemic resp. failure will result in a high or low P(A-a)O2?

A

high or normal

(normal if decreased PiO2 or hypoventilation)

79
Q

Hypercapnic resp. failure will result in a low or high PaO2?

A

Low

80
Q

Hypercapnic resp. failure will result in a low or high PaCO2?

A

High

81
Q

Hypercapnic resp. failure will result in a high or low P(A-a)O2?

A

Normal

82
Q

Combined Type I and II resp. failure result in a high or low PaO2?

A

Low

83
Q

Combined Type I and II resp. failure result in a high or low PaCO2

A

High

84
Q

Combined Type I and II resp. failure result in a high or low P(A-a)O2?

A

High

85
Q

When the vital capacity [VC] is below 15-20, what does it indicate?

A

A lack of muscle strength and lung expansion to produce a adequate cough.

86
Q

How do you know if someone doesn’t have an adequate cough based on vital capacity?

A

VC < 15-20 mL/kg

VC of 2 x Vt is needed for an adequate cough

87
Q

A normal MV is what? and when are we concenred?

A

Normal = 5-6 Lpm

Critical > 10LPM

88
Q

What is a normal MIP? and when are we concerned?

A

-80 to -100 cmH2O

Critical >= -20 cmH2O

89
Q

What does MIP measure?

A

Pt’s muscle strength

90
Q

What is a normal MEP? and when are we concerned?

A

Normal > 100 cmH2O

Critical < 40cmH2O

91
Q

Any circuit distal to the WYE is added what?

A

Mech. deadspace

92
Q

What is the point of heated wires in vent. circuits?
(2)

A

Prevents rainout

Prevent condensation

93
Q

Why are water traps on some ventilators?

A

To collect rainout

94
Q

True or False:
Frequently changing the circuit is a good way to prevent contamination and decrease the risk of vat?

A

False.

There is an increased risk of VAP with frequnet circuit changes
(no more than q7d)

Interventions 1 (RESP 266) (16 decks)

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