Questions and Answers
What is the maximum safe ratio of N2O to O2 when using a proportioning device?
What is the purpose of a hypoxia prevention device?
What is the oxygen pressure failure device?
When will the hypoxic prevention safety device not alarm?
Signup and view all the answers
What is the main difference between an oxygen pressure failure device and a hypoxia prevention safety device?
Signup and view all the answers
How does the Link 25 proportioning system work? (select 2)
Signup and view all the answers
What are the pressure and boundaries of the high pressure system? (select 2)
Signup and view all the answers
What is the pipeline pressure?
Signup and view all the answers
What is the pressure of the air from the cylinders (high pressure system) after the pressure regulator?
Signup and view all the answers
What are the boundaries of an intermediate-pressure system?
Signup and view all the answers
Where is the DISS used?
Signup and view all the answers
Where is the pin-indexed safety system used?
Signup and view all the answers
What are the boundaries of the low pressure system in an anesthesia machine?
Signup and view all the answers
What is composed of the low-pressure system?
Signup and view all the answers
What is the pressure of the low-pressure system in an anesthesia machine?
Signup and view all the answers
What system contains the failsafe device, O2 flush valve, flowmeter valve, O2 supply failure alarm, and pneumatic master switch?
Signup and view all the answers
What is the function of the flowmeter valve?
Signup and view all the answers
How do you perform a low-pressure leak test (negative pressure test) on an anesthesia machine?
Signup and view all the answers
What is a passed negative pressure leak test indicated by?
Signup and view all the answers
What should be done with the vaporizers during a negative pressure leak test?
Signup and view all the answers
How do you perform a positive pressure (high pressure) leak test on an anesthesia machine?
Signup and view all the answers
What is the primary purpose of the positive pressure leak test on an anesthesia machine?
Signup and view all the answers
When a leak is present in the low-pressure circuit, what happens to the suction bulb during a negative pressure test?
Signup and view all the answers
During spontaneous breathing, what is the position of the APL valve?
Signup and view all the answers
During manual bag ventilation, what is the position of the APL valve?
Signup and view all the answers
What is the consequence of too high or too low APL valve settings in bag ventilation?
Signup and view all the answers
What is the position of the APL valve during mechanical ventilation?
Signup and view all the answers
During mechanical ventilation, the bellows serve as the?
Signup and view all the answers
What is the position of the bellows during inspiration and expiration?
Signup and view all the answers
The vent outflow valve is the same as the ___
Signup and view all the answers
What is the purpose of the APL and vent outflow valve?
Signup and view all the answers
Modern vaporizers are outside of the circle system
Signup and view all the answers
Why does desflurane require a special vaporizer?
Signup and view all the answers
What is the purpose of the variable bypass vaporizer?
Signup and view all the answers
What is the purpose of the temperature compensating valve?
Signup and view all the answers
Where does fresh gas flow that does not come in contact with volatile agents in the vaporizer?
Signup and view all the answers
What is the definition of the splitting ratio in an anesthesia machine?
Signup and view all the answers
What happens to the output concentration of the vaporizer when the temperature of the liquid agent drops?
Signup and view all the answers
Vapor pressure is directly proportional to ___
Signup and view all the answers
What is the effect of changing pressure affecting the output of the vaporiser called?
Signup and view all the answers
During PPV, where is the pressure transmitted?
Signup and view all the answers
Where does the increased flow of backpressure travel to during positive pressure ventilation (PPV)?
Signup and view all the answers
When the positive pressure is released during PPV (i.e. exhalation), what is the result of the rapid expansion of compressed gas in the vaporizer chamber?
Signup and view all the answers
What is the end result of the pumping effect in an anesthesia machine?
Signup and view all the answers
What is the result of tipping of the vaporizer?
Signup and view all the answers
When can a leak in the vaporizer be identified?
Signup and view all the answers
How does a TEC 6 desflurane vaporizer work?
Signup and view all the answers
What is the effect of higher ambient pressure (hyperbaric oxygen tank) on the desflurane vaporizer?
Signup and view all the answers
What is the result of a lower ambient pressure (higher altitude) when using desflurane?
Signup and view all the answers
Why must desflurane be heated and pressurized to 39°C and 2 atm?
Signup and view all the answers
What is the purpose of the oxygen alternate flowmeter?
Signup and view all the answers
The master switch is normally linked to the ____ switch
Signup and view all the answers
In the intermediate system, what is the purpose of the pipeline pressure (50) being higher than the cylinder pressure (45)?
Signup and view all the answers
The O2 flush valve and auxiliary O2 are not controlled by the master switch
Signup and view all the answers
Why is oxygen used as a driving gas in the bellows?
Signup and view all the answers
How does the failsafe work in the intermediate system?
Signup and view all the answers
What is a Thorpe tube?
Signup and view all the answers
Higher flow rates tend to be which type of flow?
Signup and view all the answers
What is the ideal position of oxygen in a flowmeter?
Signup and view all the answers
What can alert you to the presence of a leak in the flowmeter?
Signup and view all the answers
What can cause retrograde flow in an anesthesia machine?
Signup and view all the answers
What is the typical flow rate of the flush valve on an anesthesia machine?
Signup and view all the answers
What is the typical pressure range of a flush valve?
Signup and view all the answers
Pushing the O2 flush valve while the patient is breathing spontaneously can result in what?
Signup and view all the answers
What are the three most important preoperative checks on an anesthesia machine?
Signup and view all the answers
How do you calibrate the oxygen analyzer?
Signup and view all the answers
What can you conclude about the integrity of the system from the flowmeter assembly to the breathing circuit if you have pressure tested your breathing system by closing the adjustable pressure limiting (APL) valve and manually occluding the Y-connector while flushing the circuit with oxygen?
Signup and view all the answers
What does the positive pressure leak test primarily test in an anesthesia machine?
Signup and view all the answers
When would you want to use transtracheal jet ventilation?
Signup and view all the answers
Where is the oxygen analyzer typically located, and what is its primary purpose?
Signup and view all the answers
How does the piston ventilator work?
Signup and view all the answers
What are the advantages of piston bellows?
Signup and view all the answers
How do piston ventilators deliver a constant tidal volume?
Signup and view all the answers
What is the consequence of coupling of VT to fresh gas flow in pneumatic bellows ventilators?
Signup and view all the answers
What is the frequency of the positive pressure leak test?
Signup and view all the answers
What is the frequency of the negative pressure leak test?
Signup and view all the answers
Study Notes
Anesthesia Machine Components and Functions
- The maximum safe ratio of N2O to O2 when using a proportioning device is 3:1 or less.
- A hypoxia prevention device prevents accidental delivery of a hypoxic gas mixture.
Hypoxia Prevention Devices
- A hypoxia prevention safety device will not alarm when the oxygen pressure is above a minimum threshold.
- The main difference between an oxygen pressure failure device and a hypoxia prevention safety device is that the former alarms when oxygen pressure drops below a set point, while the latter alarms when the oxygen percentage in the mixed gas falls below a set point.
Link 25 Proportioning System
- The Link 25 proportioning system works by sensing the oxygen pressure and adjusting the nitrous oxide flow accordingly to maintain a safe ratio.
High-Pressure System
- The pressure boundaries of the high-pressure system are between 400 and 1370 psi.
- The pipeline pressure is typically 50 psi.
- The pressure of air from the cylinders after the pressure regulator is typically 45 psi.
Low-Pressure System
- The boundaries of the low-pressure system in a hypoxia prevention device are between 10 and 14 psi.
- The low-pressure system in an anesthesia machine includes the flowmeter valve, O2 supply failure alarm, pneumatic master switch, and failsafe device.
- The pressure of the low-pressure system in an anesthesia machine is typically around 10-14 psi.
Failsafe Device and Oxygen Flush Valve
- The failsafe device, O2 flush valve, flowmeter valve, O2 supply failure alarm, and pneumatic master switch are all part of the low-pressure system.
- The function of the flowmeter valve is to regulate gas flow to the patient.
Leak Testing
- A low-pressure leak test (negative pressure test) is performed on an anesthesia machine to detect leaks in the low-pressure circuit.
- A passed negative pressure leak test is indicated by the suction bulb remaining collapsed.
- During a negative pressure leak test, the vaporizers should be turned off.
- A positive pressure leak test (high-pressure leak test) is performed to detect leaks in the high-pressure circuit.
- The primary purpose of the positive pressure leak test is to detect leaks in the high-pressure circuit.
APL Valve and Vent Outflow Valve
- During spontaneous breathing, the APL valve is open.
- During manual bag ventilation, the APL valve is closed.
- The consequence of too high or too low APL valve settings in bag ventilation is inadequate ventilation.
- During mechanical ventilation, the APL valve is closed.
- The APL valve and vent outflow valve serve to vent excess gas from the breathing circuit.
Vaporizers
- Modern vaporizers are outside of the circle system.
- Desflurane requires a special vaporizer that is heated and pressurized to 39°C and 2 atm.
- The purpose of the variable bypass vaporizer is to maintain a consistent output concentration despite changes in temperature or pressure.
- The purpose of the temperature compensating valve is to adjust the vaporizer output concentration based on temperature changes.
Anesthesia Machine Operation
- The splitting ratio in an anesthesia machine is the proportion of fresh gas that flows through the vaporizer versus that which bypasses it.
- The output concentration of the vaporizer increases when the temperature of the liquid agent drops.
- Vapor pressure is directly proportional to temperature.
- The effect of changing pressure affecting the output of the vaporizer is called the pumping effect.
Pressure and Flow
- During PPV, pressure is transmitted to the breathing circuit.
- The increased flow of backpressure travels to the vaporizer chamber during PPV.
- When the positive pressure is released during PPV, the result is a rapid expansion of compressed gas in the vaporizer chamber.
- The end result of the pumping effect is an increased output concentration of the vaporizer.
Desflurane Vaporizer
- The TEC 6 desflurane vaporizer works by heating and pressurizing the desflurane to 39°C and 2 atm.
- The effect of higher ambient pressure on the desflurane vaporizer is an increased output concentration.
- The result of a lower ambient pressure when using desflurane is a decreased output concentration.
- Desflurane must be heated and pressurized to 39°C and 2 atm to achieve a consistent output concentration.
Miscellaneous
- The oxygen alternate flowmeter is used to measure oxygen flow separately from other gases.
- The master switch is normally linked to the O2 flush valve switch.
- Pipeline pressure (50) is higher than cylinder pressure (45) to ensure a reliable supply of oxygen to the anesthesia machine.
- Oxygen is used as a driving gas in the bellows because it is safer and more efficient.
- The failsafe device in the intermediate system shuts off the machine in case of failure.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.