Mechanical Ventilators Flashcards Preview

Cardio Pulm > Mechanical Ventilators > Flashcards

Flashcards in Mechanical Ventilators Deck (38):
1

Purpose of Ventilator

-decrease WOB
-provide ventilation (not respiration)
-maintain positive pressure

2

Mechanical Ventilator

-process by which ventilation is maintained by an artificial or extrinsic means
-machine used to force gas into lungs

3

Indications of ventilator use

-inability to spontaneously ventilate
-disorder of gas exchange (unable to get O2 in or CO2 out)

4

Negative Pressure Ventilator

-Iron Lung
-change in pressure in caase around chest to increase/decrease intrathoracic pressure to ventilate patient

5

Pressure Support Ventilation

-pt must have adequate spontaneous effort
-provide preset amount of pressure during spontaneous effort to support pt efforts

6

Acute/impending respiratory failure

-pH 50mmHg

7

Types of Ventilators

-negative pressure (iron lung)
-positive pressure

8

Positive Pressure Ventilator

-blows air into lungs
-affected by compliance and resistance

9

Volume-Cycled ventilation

ends inspiration after a preset tidal volume has been delivered

10

3 types of positive pressure ventilation

-volume-cycled
-time-cycled
-flow-cycled

11

Time-cycled ventilation

-ends inspiration after preset time has elapsed

12

Flow-Cycled

-ends inspiration when a preset flow rate is obtained

13

CPAP

-applies continuous positive pressure during inspiration and expiration to a spontaneously breathing person
-pressure prevents alveolar collapse, increased fuctional/residual capacity and oxygenation

14

Indications for CPAP

-atelectasis
-sleep apnea

15

Advantages vs Disadvantages of CPAP

ADV-maintain respiratory strenth, used to wean from partial vent support

DIS-possible compromise to CO

16

Advantages vs Disadvantages of SIMV

ADV: to wan pts from vent, less likely to hypervent, CO less compromised

DIS: utilize demand valve that opens and allows airflow in response to certain neg pressures

17

Assist Control Ventilation

-preset rate and tidal volume programmed, which are delivered in absence of spontaneous effort
-in response to effort, will assist pt's efforts by delivering the tidal volume

18

Indications of Assist Control Ventilation

pt with respiratory Mm fatigue, pulm edema or pneumonia

19

Advantages vs Disadvantages of Assist Control Vent

ADV: pt may participate in vent

DIS: possibly hyperventilate

20

Advantages vs Disadvantages of Pressure Support Ventilation

ADV: incr tidal volume to decr WOB & aids in weaning

DIS: difficult to ensure alveolar vent; no air given in absence of voluntary effort; increase tidal volume & decr RR

21

BiPAP

-similar to CPAP but gives different levels of pressure during inhale and exhale
-help deliver more air to lungs
-used for same problems as CPAP

22

Ventilator Parameters

-tidal volume
-RR
-FiO2
-PEEP
-PIP

23

PIP

-peak inspiratory pressure
-how much force is needed to get air into lungs
-if have restrictive or intubated=need greater amount
-trauma risk: barotrauma

24

High Pressure Alarm

-alarms when PIP exceeds preset limit
-indicates obstruction in tracheal tube or pt coughing/being agitated
-may indicate worsening condition

25

Low PEEP/CPAP alarm

-when preset PEEP or CPAP not maintained

26

Low exhaled volume alarm

-when exhale volume is < tidal volume
-indicates pt disconnected from tracheal tube or leak in cuff around tube

27

6 Alarms

-high/low pressure alarms
-low PEEP/CPAP alarm
-High/low exhaled volume alarm
-apnea alarm

28

Low pressure alarm

-when tidal volume uses pressure below average PIP
-indicates leak in system

29

High Exhaled Volume Alarm

-pt getting more than preset minute ventilation
-if pt incr RR or agitated

30

Apnea Alarm

-when no air movement detected for period of time
-indicates system failure or nonexistent O2 supply
-initiate emergency procedures ASAP

31

factors affecting weaning

-ABGs
-PFTs
-Presence of Contraindications

32

Weaning Complications

-Atelectasis
-Aspiration
-Hypoxemia

33

Signs of respiratory distress during mechanical vent

-increased SCM contraction
-recession of suprasternal and supraclavicular spaces and intercostal spaces
-paradoxical motion of abdomen
-diaphoresis
-nasal flaring
-tachycardia
-tachypnea
-cyanosis

34

Contraindications to weaning

-Required PEEP >5cm H20
-if FIO2 >0.4
-Unable to generate negative inspiratory pressure >/= 20 mmHg

35

5 modes of ventilation

-assist-control ventilation
-synchronized intermittent mandatory vent (SIMV)
-Pressure support vent
-CPAP
-BiPAP

36

SIMV

-programmed to deliver preset tidal volume and frequency
-if pt fails to initiate, will deliver tidal volume and rate
-if pt initiates, tidal volume depends on muscular effort by pt

37

PEEP

-positive end expiratory pressure
-used to maintain open airways
-increased PEEP=worse the pt is

38

monitoring needs
(for weaning)

-ABGs
-Vitals
-S/Sx respiratory distress