Brainscape's Knowledge GenomeTM

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


See full index

001 Respiratory Therapy > Ventilator Waveforms > Flashcards

Ventilator Waveforms Flashcards

1
Q

What is the square wave?

A

It utilizes a high-pressure source (from the machine), the flow peaks and stays constant, uninfluenced by changes in resistance and compliance.

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

When is the square wave used?

A

It is used with patients with non-compliant (stiff) lungs and increased respiratory rates. It decreases inspiratory time and has better air distribution/gas exchange.

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

What is a caution of the square wave?

A

It could increase peak airway pressure and the mean airway pressure. It pushes too quickly. You should use the lowest possible pressure.

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

What is the sine wave?

A

It is the same pattern, breath after breath but the flow is not constant. It is most like normal breathing. The sine wave uses decreased airway resistance by decreasing flow; decreases peak airway pressures.

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

What is a caution of the sine wave?

A

It may result in a decrease in mean airway pressure (MAP).

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

What are scalars?

A

Plots of pressure, flow, or volume against time.

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

What are loops?

A

Plots of pressure, flow, or time against each other. Time is not graphed.

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

What are the types of volume control flow delivery waveforms?

A

Square, ascending, descending, and sine.

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

What are the types of pressure control flow delivery waveforms?

A

Descending and decay.

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

What do square waveforms represent?

A

A constant or set parameter.

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

What do ramp waveforms represent?

A

Parameters that vary with changes in lung characteristics.

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

When are sine waves seen?

A

Spontaneous, unsupported breathing.

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

How do you identify a ventilator-initiated mandatory breath?

A

A pressure rise without a pressure deflection below the baseline.

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

How do you identify a patient-initiated breath?

A

A pressure deflection below baseline right before a rise in pressure.

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

How do you identify spontaneous breaths?

A

Pressures above and below the baseline.

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

How do you identify pressure support breaths?

A

A rise to a plateau and a display varying inspiratory times.

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

How do you identify pressure control breaths?

A

A rise to a plateau and display constant inspiratory times.

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

PEEP is set to no more than what percentage of auto-PEEP?

A

80%

19
Q

What is asynchrony?

A

It is known as “flow starvation”. The inspiratory portion of the pressure waveform shows a dip due to inadequate flow.

20
Q

What happens to the waveform, PIP, and Pplat when compliance decreases?

A

The waveform size increases while the difference in PIP and Pplat remain the same.

21
Q

How do you identify a leak on a pressure-time curve?

A

The baseline pressure dips downward and the low-PEEP alarm will go off.

22
Q

When inspiratory flow takes longer to return to baseline, what does this indicate on a flow waveform?

A

Airway obstruction.

23
Q

When expiratory flow doesn’t return to baseline, what does this indicate on a flow waveform?

A

Air trapping

24
Q

On a pressure-volume loop, describe if inspiration and expiration is upward or downward?

A

Inspiration = upward; Expiration = downward.

25
Q

On a pressure-volume loop, what does beaking suggest?

A

Overdistention.

26
Q

What does fishtail indicate?

A

Negative pressure (flow or pressure trigger).

27
Q

An increase in airway resistance causes the pressure-volume loop to do what?

A

It causes it to widen.

28
Q

What does a leak in the pressure volume loop means

A

That a leak is present.

29
Q

What does a shift upward indicate on a pressure-volume loop?

A

Increased compliance.

30
Q

What does a shift downward indicate on a pressure-volume loop?

A

Decreased compliance.

31
Q

What indicates a leak on a flow-volume loop?

A

The expiratory part of the loop does not return to the starting point.

32
Q

Which flow pattern decreases the risk of barotrauma in PCV?

A

Ascending ramp.

33
Q

What does the vertical and horizontal axis represent for a pressure-time waveform?

A

Vertical = pressure; horizontal = time.

34
Q

What can cause oscillations on exhalation?

A

1) It could simply be the tubing laying on the patient picking up motion from the heart rate.
2) It could be secretions in the airways.
3) It could be condensation in the tubing.
4) Secretions in the vent tubing.

35
Q

What can cause dyssynchrony?

A

1) Not enough flow for your patient,
2) Sensitivity set to hard for the patient,
3) Improper sedation.

36
Q

How can you correct insufficient flow?

A

Decrease i-time or increase peak flow. Also, a change in mode can help.

37
Q

Which waveform is most likely to show a square wave or descending wave pattern?

A

Flow time waveform.

38
Q

Which waveform is most likely to determine a sensitivity setting problem?

A

Pressure time waveform.

39
Q

What is the square waveform used to calculate?

A

It is used to accurately calculate the airway resistance on some ventilators.

40
Q

Describe the square wave flow pattern:

A

A set peak flow is delivered at beginning of a breath. The flow is constant throughout the entire inspiratory phase. It may produce higher peak pressures and may decrease the inspiratory time significantly.

41
Q

Describe the descending ramp flow pattern:

A

The set peak flow is delivered at the beginning of a breath, then it decreases in a linear fashion until the volume is delivered. It may produce lower peak pressures (usually desired outcome). It may increase inspiratory time significantly (may lead to Auto-PEEP). It is the most popular waveform choice thought to improve the distribution of ventilation.

42
Q

Why are square wave and decelerating patterns the most commonly used?

A

For their initially high inspiratory flow, they provide better patient-ventilator synchrony.

43
Q

What are the four types of inspiratory flow patterns?

A

Square/constant flow waveform (CFW); Decelerating /Descending Ramp flow waveform (DRFW); Accelerating; and Sine.

001 Respiratory Therapy (53 decks)

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