Module 1 Exam: Classifications of Ventilation

Question 1

List the powering mechanisms

Answer 1

Electric, Pneumatic, and combined

Question 2

How do you know if a machine is powered?

Answer 2

Look at machine to tell how its powered

Question 3

What is the purpose of pneumatically powered vents?

Answer 3

To supply a gas that controls gas flow

Question 4

What is the purpose of driving mechanisms?

Answer 4

Controls the direction of pressure/flow seperately

Question 5

What vents are required for MRI?

Answer 5

Pneumatics and Fluidics

Question 6

List the driving mechanisms

Answer 6

Pnuematic: clutch-valve, Servo, Solenoids, regulator, fluidics (not commonly used any longer)
Piston (electrically powered)- Linear Rotary
Bellows- driven by compressed gas source, may use one way valve, and compressed springs or weight if in a sealed chamber.
Microprocessor- all modern-day ventilators pneumatic controlled drive battery back-up

Question 7

What is a control variable?

Answer 7

The variable measured by the ventilator control circuit and used feedback signal to control ventilators output.

Question 8

List the control variables

Answer 8

Volume, pressure, flow and time is controlled by the vent during inspiration

Question 9

In volume ventilation what variables change from breath to breath?

Answer 9

Pressure and flow

Question 10

In pressure ventilation what variable changes

Answer 10

volume and flow

Question 11

Control variables are responsible for inspiration or expiration?

Answer 11

Inspiration

Question 12

List the cycles of ventilation

Answer 12

flow, pressure, volume or time

Question 13

Define cycle?

Answer 13

When to stop inspiratory flow

Question 14

Define limit?

Answer 14

Maximum amount of cycling of flow, time, pressure, and volume can attain.

Question 15

List 5 phase variables

Answer 15

Trigger (pressure- set-1 to -2, flow-1 to 3LPM, manual) limit, cycle, baseline, and conditional variable

Question 16

What are to ways to ventilate a patient?

Answer 16

Pressure and Volume

Question 17

What are 3 things set on a pressure vent?

Answer 17

Pressure, flow, and rate

Question 18

Define positive pressure ventilation

Answer 18

Set pressures being delivered to the airway that is higher than alveolar spaces.

Question 19

What are some positive pressure vents?

Answer 19

Drager V500, PBI80 and PB 840, LTV 1200, and Evita

Question 20

What are some negative pressure vents?

Answer 20

Iron lung and Chest cuirass

Question 21

Define double circuited?

Answer 21

Ventilators that have 2 gas flows one to patient and one to machine. (1 limb)

Question 22

Define single circuited?

Answer 22

ventilators in which the gas supply that powers the machine is the same gas to the patient. (2 limbs)

Question 23

Define tubing compliance?

Answer 23

The amount of gas that is compressed in the circuit for every cmH2O generated during inspiration

Question 24

Define compressed volume?

Answer 24

Amount of volume lost in the circuit due to tubing compliance - volume varies depending in the type of circuit.

Question 25

Define internal resistance?

Answer 25

How well the flow pattern and pressure pattern can be maintained in the presence of back pressure

Question 26

What is the flow wave patterns?

Answer 26

Square- a constant, depending on internal resistance to determine if it changes with back pressure Sine- gradually increase flow until mid-inspiration due to action of rotary piston Accelerating- gradually accelerates to peak and levels off Decaying- reaches peak flow immediately, then gradually decelerates (air-mix)

Question 27

What are the pressure patterns?

Answer 27

Reticular- due to square wave Sigmoidal- due to sine wave Exponential- due to accelerating wave Parabolic- due to decaying

Question 28

What determines shape of a waveform?

Answer 28

internal resistance

Question 29

What are the alarms for ventilators?

Answer 29

O2 disconnect high pressure/low pressure high/low volume fail to cycle High/low PEEP Time (I:E ratio) Apnea

Question 30

Pressure patterns are determined by.

Answer 30

Flow patterns

Question 31

High/Low alarms indicate?

Answer 31

High alarms indicate- Obstruction /blockage Low alarms indicate leaks/disconnect

Question 32

What type of alram is O2 disconnect?

Answer 32

Low alarm/ low pressure limit, peep/cpap

Question 33

What can cause low pressure alarms?

Answer 33

Disconnect, cuff leak, increased patient demand

Question 34

What can cause high pressure alarms?

Answer 34

Cough, Biting ETT tube, Fighting VENT, needs suctioning, or kinked ETT tube

Question 35

What can cause apnea alarm?

Answer 35

Disconnect or true apnea event (20 seconds)

Question 36

What causes I:E ratio alarms?

Answer 36

Duration of inspiration is 50% or > OF TCT

Question 37

When is low peep are activated?

Answer 37

Presence of leak in the patient ventilator circuit

Question 38

Define trigger?

Answer 38

What initiates the start of inspirations

Question 39

What controls the I:E ratio setting?

Answer 39

The respiratory rate

Question 40

What is the purpose of PEEP?

Answer 40

To keep the alveoli, open during expiratory phase to allow gas exchange

Question 41

What are the hazards of PEEP?

Answer 41

Air trapping and barotrauma

Question 42

What is control mode?

Answer 42

All WOB is taken over by ventilator Sedation required Useful with ARDS when inversed ratio is required Pressure varies Patient cannot trigger breath Preset volume and rate

Question 43

What is A/C- V/C mode?

Answer 43

Constant preset volume Pressure varies with each breath Patient can trigger breath Machine performs majority WOB No spontaneous volumes Sedatives administered to prevent hyperventilation

Question 44

What is SIMV mode?

Answer 44

Set VT and RR pt. can breathe spontaneously between breaths Weaning and short term

Question 45

What mode is PSV?

Answer 45

Delivers kick of pressure at the beginning of inspiration to help overcome increased resistance Patient can trigger breath Positive pressure set Pt. can set own RR, VT, and flow Used with CPAP and SIMV Helps reduce WOB by ETT and tube

Question 46

What mode is CPAP?

Answer 46

Pt. control RR, VT, AND FLOW

Question 47

What mode is MMV?

Answer 47

Replaced by ASV Adaptive Support Ventilation

Question 48

What mode is BIPAP?

Answer 48

Similar to CPAP but applies high pressure during inspiration and lower pressure during exhalation Obstructive sleep apnea Severe air rapping

Question 49

Study advanced modes