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Flashcards in modes of ventilation Deck (42):
1

Types of Breaths

-Mandatory
-Assisted
-Spontaneous

2

What does mandatory mean?

machine starts breath and machine controls and ends the breath. Vent does all the work.

3

What does assisted mean?

Patient starts the breath and the machine controls and ends the breath.

4

What does spontaneous mean?

Patient starts the breath, patient controls and end the breath. Machine augments breath.

5

What is the difference between volume controlled and pressure controlled?

-The term CMV usually refers to volume ventilation or VCV
-Pressure controlled CMV is usually called PCV or P-AC
-Most modes assume volume unless prefixed by "P"

6

Continuous Mandatory Ventilation (CMV)

-All breaths are mandatory-full support
-Only appropriate when a pt makes no effort at breathing or when you want to completely control ventilation.
-The machine only triggers by time. Pt cannot add rate by assisting.
-Can be used for frail chest (2 or more broken ribs in 2 or more places)

7

What are indications for CMV?

-tetanus/seizure
-complete rest-24hrs
-crushed chest injury w/paradoxical movements
-cerebral malfunction
-spinal cord/phrenic nerve injury
-paralysis
-drugs

8

What are some complications with CMV?

-potential for apnea/death with disconnection
-important alarms-low pressure, low exhaled volume
-therapist must recognize spontaneous effort by patient and correct

9

What triggers, limits, and cycles CMV?

-trigger-->time
-limit-->volume (flow)
-cycle-->time/volume
-expiration-->passive, PEEP

10

Assisted Control (A/C) Ventilation

-all mechanical breaths-full support
-may be poorly tolerated in awake pts
-COPD pt may air trap
-Pts with rapid drive may hyperventilate

11

What triggers, limits, and cycles AC?

-trigger-->time/pts
-limit-->volume
-cycle-->volume/time

12

What are some common causes of rapid drive?

-anxiety
-pain
-hypoxemia
-metabolic acidosis
-inappropriate ventilator settings

13

How do you correct the drive?

by switching modes or sedate the patient

14

Here is more info on Assist Control Ventilation

-machine has a guaranteed min
-Pt determines maximum
-set rate @ 2 like pt is in control mode

15

Assisited Control (P-AC) Ventilation (PRESSURE)

-can also be PCV or PC-AC
-May reduce WOB since pt chooses own flow

16

what is P-ramp?

sloping the inspiratory pressure curve

17

What does IMV stand for?

Intermittent Mandatory Ventilation

18

What triggers, limits, and cycles IMV?

trigger-->time
limit-->flow
cycle-->volume/time

19

Does IMV cause breath stacking?

yes, because even if the patient is spontaneous breathing the vent will still deliver a breath.

20

What is SIMV?

synchronized intermittent mandatory ventilation

21

What is the differnence between IMV and SIMV?

-IMV is both mechanical and spontaneous breath and gives partial ventilatory support
-SIMV is just like IMV but mechanical breaths are PT/time triggered. Pt can also regulate own CO2 and pH.

22

What are some disadvantages of SIMV?

-SIMV with high PSV may increase WOB
-Acute hypoventilation may occur at lower rates
-Weaning may be prolonged
-PSV is needed to overcome WOB
-Fatique may occur in pts who have rapid shallow breathing

23

What triggers, limits, and cycles P-SIMV?

-trigger-->pts/time
-limit-->pressure
-cycle-->time
-compliance/resistance-->flow/volume
-spontaneous breaths in between
-they are pt triggered and pt cycled

24

Pressure Support Ventilation (PSV)

-spontaneous mode on vent
-augmented spontaneous breathing
-like PCV delivers a high flow of gas at beginning and then it tapers when pressure gradient equalizes
-decrease WOB by overcoming resistance to tubing and circuit.

25

What triggers, limits, and cycles PSV?

-trigger-->patient
-limit-->pressure
-cycle-->flow

26

What is expiratory time sensitivity?

-ETS adjusts the flow cycle level of pressure supported breaths.
-In the event of leak, ETS % can be adjusted that pressure supported breaths will end. Maximum setting is 45% which will be effective for all but large leaks.

27

What are 2 applications for PSV?

-PSV and SIMV: used to overcome resistance in tubing, poor demand flow and airways.
-Stand alone PSV: what ever is needed to achieve VT of 10-12 mL/Kg than titrated to let pt do more work.

28

What does CPAP and PEEP mean?

Continuous Positive Airway Pressure and Positive End Expiratory Pressure
-used to describe baseline
-CPAP is used with spontaneous breathing
-PEEP is used with mechanical breathing

29

SIMV with PSV

-combines 2 modes of A/C (with limit # of breaths) and PSV during the spontaneous breaths
-used all the time

30

PSIMV with PSV

-a combination of pressure assist/control breaths and PSV during spontaneous breaths

31

SIMV c PSV and CPAP

-add PEEP to the mix
-remember they are volume targeted machine breaths
-machine breaths are pressure targeted

32

Mandatory Minute Ventilation

-used for weaning
-set MV at 70-90% of current VE
-vent provides rest
-vent monitors spontaneous MV when it drops below set level the vent provides mechanical support to make up difference

33

Two ways of Mandatory Minute Ventilation

-increasing the breath rate (bear 1000)
-increasing the preset pressure (Hamilton)
-machine reads total volume in one minute, pt can breath at low volume very fast and keep same Min volume
-must set high flow and low Vt correctly

34

What are other terms for trigger?

-trigger
-sensitivity
-initiate
-start
-change from E to I
-begin the breath

35

What are other terms for inspiration (pressure limited)?

-pressure controlled
-pressure targeted
-pressure limited
-pressure oriented
-the machine reaches a set pressure and maintains that pressure during the breath
-flow varies with lung changes
-volume varies with lung changes

36

What are other terms for inspiration ( volume limited)?

-volume oriented
-volume targeted
-volume limited
-volume controlled
-flow controlled
-volume does not change with lung
-pressure varies with lung changes

37

What are other terms for cycle?

-cycle
-end of breath
-terminated
-extinguish
-begin expiration
-change from I to E

38

what mode is started by the machine or pt, pressure is guaranteed, inspiration is terminated when a set time has elapsed?

-pressure mode
-pressure assist control

39

What are all the volume modes?

-control
-A/C
-IMV (control and spont)
-SIMV (assist/control and spont)
-SIMV c PSV (assist/control and PSV)

40

What are all the pressure modes?

-PSV
-PC/AC, P-AC, PCV
-PSIMV-PAC(PC) and spon
-PSIMV c PSV

41

What mode of ventilation is a mixture of assist/control, pressure oriented, time cycled breaths and flow triggered, pressure oriented, flow cycled breaths?

PSIMV/PSV

42

What mode of ventilation begins inspiration with flow, allows volume to vary during the breath, and begins expiration after a predetermined low flow is reached?

PSV