Classifications of Ventilators Flashcards
What does the Chatburn Classification System have?
Input power source, positive/negative pressure, control systems and circuits, power transmission, and output
What are the options of the input power source?
Electric, pneumatic, combined, manual
What are the parts of the control systems and circuits?
Open vs closed loop, control panel and pneumatic circuit
What are the parts of the power transmission?
Compressor or bellows, volume displacement design, flow control valves
What is included in output?
Pressure waveforms, volume waveforms and flow waveforms
What does it mean when something is pneumatically powered?
It is powered by a 50 psi gas source
What do negative pressure ventilators do?
“Pull” open the lungs
What do positive pressure ventilators do?
“Push” open the lungs
What are the two parts to the pneumatic circuit of the control system?
Internal circuit (single or double circuit) and external circuit (tubing to patient)
What is another term for an open system?
Unintelligent
What does it mean when a ventilator is “unintelligent?”
You set the parameter and it delivers with “no questions asked”
What is another term for a closed system?
Intelligent
Where is the control panel located? What does it do?
It is the outside surface of the ventilator and is monitored/set by the user. It governs the four physical parameters: volume, time, pressure and flow
What is an internal control system?
It reads and interprets what is set and controls the function of the drive mechanism
What is a double circuit?
It is two sources of gas that never mix together
What is the external circuit?
It is outside of the machine and it connects the vent to the patient’s airway
What does the external circuit consist of?
The main inspiratory line, “wye” adapter to the patient, expiratory line, expiratory valve (internal or external)
What are some devices that are used with patient circuits?
Air warmer/humidifier, temperature sensing device, an apnea or low pressure alarm, nebulizer line, volume measuring device, bacteria filter and a proximal pressure gauge
What is power transmission and conversion?
Conversion of power source to work and work provided by the drive mechanism
What are some volume displacement designs?
Bellows, pistons, flow valves and solenoids
What is the purpose of volume displacements?
Volume controllers
What are some examples of flow control valves?
Proportional solenoids, stepper motion with valve, digital valve (on/off configuration)
What is a flow control valve?
It delivers flow for a specific amount of time. Not measuring volume but guaranteeing it
What are the kinds of bellows and pistons used?
Spring loaded bellows, linear or rotary drive pistions
What are compressors or blowers used for?
Used as the power source or for converting and transmitting a power source
How can you change a compressor volume?
By compressing space that will increase pressure
How do compressors run?
They can be piston driven, rotary blades, moving diaphragms or bellows
What does a drive mechanism do?
It generates the actual force needed to deliver gas under pressure
What does output control consist of?
One or more valves that regulate flow to the patient
Power transmission and conversion consists of?
Drive mechanisms and output control mechanisms
Large compressors supply _________ that provide power to ventilators
Wall outlets
Some ventilators have built in _________ to be used when power is not available (or sometimes even as the main source)
Compressors
Most modern vents have __________. These _______ control or direct gas flow and can open/close completely or in small increments
Flow control valves; valves
What are flow control valves driven by?
Various motor-based mechanisms
Flow control valves have ______ response time and are very _______
Rapid; flexible
What happens when you attach a piston to a wheel?
Produces a different flow pattern (the speed will be much faster in the middle of the breath). More physiologic
