Who devised the first classification system for describing the first vents
Who has been trying since 1980s to update vent and mode description
Historically what do classification systems attempt to accomplish
The physical function of the vent
What are 2 things chatburns classification attempt to accomplish
- Characteristics like power source
- Breathing pattern
What is the major source of confusion regarding the different modes of ventilation
The different names
What another name for the control panel
What are 4 power sources for a ventilator
What are the 2 basic types of pneumatically powered vents
Pneumatic and fluidic
What are 3 types of pressure vents
- Positive pressure
- Negative pressure
- Combined pressure
Give an example of positive pressure vent
Give an example of a negative pressure vent
Give an example of a combined pressure vent
High frequency vents
What type of vent is most common
Give an example of a closed loop system
A robot pouring 1 L into a .75 L container not looking it over flows
How is closed loop different from open loop
It monitors volume delivered by the ventilator and exhaled by the patient and makes adjustments as needed
What are other terms used to describe closed loop systems
- Servo controlled
- Intelligent system
What is the difference between single and double internal pneumatic circuit
- Double has 1 gas source that powers the unit and another that goes to the patient
- Single only has 1 gas source for both unit and patient
What is another name for the external circuit
- Vent circuit
- Patient circuit
Why do almost all new vent circuits have an external exhalation valve
For its low resistance, large diameter and flexible plastic diaphragm
What is the power transmission device for pneumatically powered microprocessor controlled system vents
Flow control valve
Give an example of Compressor or Blowers
Give an example of Volume-displacement
Give an example of Linear-drive piston
Give an example of Rotary, or nonlinear-drive piston
- Lifecare PLV-100, 102
- PB Companion 2801
Give an example of Spring-loaded bellows
What are the three different types of Flow-controlling valves
- Proportional solenoid valve
- Stepper Motors with Valves
- Digital Valve
Give an example of proportional solenoid Valve
- Hamilton Galileo
- Drager Evita XL
- Marquet Servo i
Give an example of stepper motors with valve
Give an example of digital valve on/off configuration
Give an example of a Fluidic ventilator, and where they are most often used.
Biomed MPV 10 most often used in transport vents
Older expiratory valves had what two major problems?
Increased resistance to gas flow when expiratory flow was high or when the patient coughed into the vent
How is PEEP accomplished by the expiratory valve?
Flow resistance or threshold resistance
Where is Spring-loaded PEEP valves most commonly used?
On manual resuscitation bags
What ventilators use electromagnetic expiratory valves?
- Marquet Servo I
- Hamilton Veolar Ventilators
What are the two forces available to perform (the) work of breathing?
- The patients muscles
State the equation of motion
Pmus+Pvent=(V/C)+(Raw x Flow)
Define: mandatory breath
The ventilator controls the timing/size of the breath
Define: assisted breath
One or all part of the inspiration is performed by the ventilator
Define: spontaneous breath
The patient controls the transition from inspiration to expiration
Define: control variable
Parameter or variable controlled by the ventilator for any given breath
What are the three main control variables:
What are the other terms for volume-targeted ventilation?
- Volume Ventilation
- Volume Control
- Volume Limited Ventilation
What are the other terms for pressure-targeted ventilation?
- Pressure Ventilation
- Pressure controlled Ventilation
- Pressure limited Ventilation
What are the two parts of the total cycle time (TCT)?
Inspiration and Expiration
What are the four parts of the mechanical breath?
- Trigger Variable
- Breath Delivery (inspiration)
- Cycle Variable
- Limit Variable
What does the Trigger Variable do?
If the ventilator is �trigged� by time, what type of breath is being delivered?
What are the two major variables used to trigger (other than time)?
Pressure and Flow
Describe the three locations for the pressure transducers or sensors so the machine may sense patients� inspiratory effort.
- Within the internal ventilator circuit near the point where the gas flow leaves
- Where the expired gas returns to the unit from the patient
- At the proximal airway
What is another term for the background flow used in flow triggering?
Base or Bias flow
What machine can use a Neural triggering mechanism, and what is the abbreviation for this system?
NAVA (servo i)
How were the first positive-pressure volume ventilators classified?
Based on power source
How many variables can the ventilator control at a time?
If the ventilator is operating in a pressure-controlled manner, are the delivered volumes and flows consistent manner when a patient�s lung characteristics change?
Give two examples of time controlled breaths/modes.
- High frequency jet ventilation
- High frequency oscilation
What does ramping mean? Are there another terms used to describe this control?
Adjusting the slope of the pressure and flow curves at the beginning of inspiration
What are the three variables graphed over time (i.e. scalars)?
What is the maximum safety pressure usual setting? And what are the common names used for this control?
- 10 cm H2O
- Pressure limit, Upper pressure limit, High pressure limit
What is the purpose of Maximum Safety Pressure?
To prevent excessive pressure form damaging lung tissue
How do newer ICU ventilators prevent excessive airway pressures from developing when a patient coughs?
The exhalation valve may float
What is the term for the phase that ends the inspiratory phase?
What four variables can end the inspiratory phase?
- Volume Cycling
- Pressure Cycling
- Time Cycling
- Flow Cycling
What is the most frequent form of pressure cycling?
Occurs when a vent reaches the upper pressure limit set above the peak inspiratory pressure to ventilate the patient
What happens to the ventilator when the inspiratory pause is activated
Delivery of inspiration the closing of both insp and exp valves for a fraction of a second
What are some other terms used for this control setting
- Inflation hold
- Inspiratory plateau
What does the term �tubing compliance factor� describe?
Volume that can be lost while the circuit expands during inspiration and returns to the NL during exhalation
What is the typical TCF in adult circuits?
Which mode of ventilation most often uses flow cycling?
What is the term for the pressure reading at the end of an inspiratory pause?
How is this pressure reading used to calculate the average alveolar pressure
What type of lung-thoracic compliance is calculated at this pressure?
Why would you extend the Ti out beyond the time needed to deliver the tidal volume?
To increase MAP and potentially improve patients oxygenation
Finish the sentence: �The expiratory phase is the�.�
Time between inspiratory time
Finish the sentence: �A zero baseline pressure is�.�
Equal to atmospheric pressure
Why do we perform the procedure called expiratory hold?
To estimate the pressure in the patients lung and vent circuit caused by air trapping
What happens if the patient makes an inspiratory effort during the expiratory hold?
The reading cannot be obtained
Give three interventions to reduce auto-PEEP:
- Lower Ve
- Increase Flow