Anesthesia Machine Flashcards
Name 2 components that are located in the low pressure system in the anesthesia machine? (4 total)
Thorpe tubes (flowmeter tubes) and the common gas outlet
Also vaporizers and check valves (if present)
(Begins at flowmeter tubes and ends at common gas outlet)
Name 4 components that make up the high pressure system?
Hanger yoke Yoke block with check valves Cylinder pressure gauge Cylinder pressure regulators (Begins at cylinder and ends at cylinder regulators)
This is used to prevent the wrong cylinder from being attached to the anesthesia machine?
This prevents the wrong gas hose from being attached?
*Filtering and exchanging air in the OR is not a function of the anesthesia machine
PISS (pin index safety system)
DISS (diameter index safety system)
- Place cylinder like this when not in use?
- Remove the ___ from the port before installing the cylinder. Failure to do so may obstruct gas flow.
- On its side
- Plastic cover
This will activate when the oxygen tank is exhausted or oxygen pressure in the supply line is less than 30 psi?
Oxygen pressure failure device
- This will limit the nitrous oxide flow to 3 times oxygen flow?
- This reduces and or stops the flow of nitrous oxide when pressure in the oxygen pipeline falls below 30 psi?
- This will alarm if the FIO2 is less than 21%?
- This device will not prevent a hypoxic mixture if a gas other than nitrous oxide is used (example: helium)?
- Hypoxia prevention safety device
- Oxygen pressure failure device
- Oxygen analyzer
- Hypoxia prevention safety device
Area between the widest area of the indicator float and side wall of the flowmeter?
Annular space
The Isoflurane dial is set to 2%. What percent of fresh gas exiting the vaporizing chamber is saturated with Isoflurane?
100%
The Tec-6 Vaporizer:
- Is pressurized to ?
- Its output is increased inside a ?
- It is heated to ?
- Uses an injector design, not a flow over design (iso, Sevo etc.)
- 2 atmospheres
- hyperbaric chamber
- 39 degrees Celsius
What two actions should be carried out in the event of an oxygen pipeline crossover?
Disconnect the pipeline supply (key step!!!) and
turn on the oxygen tank
- Only device downstream of the flowmeters that can detect a hypoxic mixture?
- Located in the?
- Only the oxygen analyzer measures ___. Thus only component that can detect a crossover.
- Oxygen analyzer
- Inspiratory limb of the breathing circuit
- oxygen concentration (the others detect oxygen pressure)
Most common cause of low circuit pressure is ?
If this is not listed this is second best answer?
Disconnect at the Y piece
CO2 cannister
Oxygen flush valve:
- The risk of barotrauma is minimized by ventilators with?
- Excessive use may lead to ?
- Delivers a continuous oxygen flow of?
- During inspiration, the ventilator drive gas closes the ___. Pressing the oxygen flush valve will have no effect on this function.
- fresh gas decoupling
- awareness
- 35-75 L/min (NOT A PRESSURE of 35-75 psi)
- ventilator spill valve
- The drive gas ____ the bellows and ____ the spill valve.
- Fresh gas from the ventilator goes to ____.
- Expired gas ____ the bellows.
- When circuit pressure is ____, expired gas is directed through the spill valve to the ____.
- compresses the bellows and closes the spill valve
- the patient
- refills the bellows
- greater than 2-4 cm H2O
- scavenger
Critical to not press the oxygen flush during ____ when patient on ventilator. Risk of barotrauma since ___ is closed.
If oxygen flush is pushed during ____ the excess flow will first fill the bellows then the rest is vented out the scavenger.
Inspiration!!!
Ventilator spill valve is closed
Expiration
What is the first monitor that will detect an oxygen pipeline crossover?
Oxygen analyzer
- A ___ may transmit the high gas pressure to the breathing circuit and cause barotrauma.
- If there is a bellows leak and oxygen is used as the ventilator drive gas, the FIO2 in the breathing circuit may ____.
- A leak in the bellows
- increase
- This ventilator does not require oxygen as a drive gas, thus will not consume tank oxygen in the event of an oxygen pipeline failure?
- It also allows for more precise?
- It does not couple ____ with the ventilator.
- Any ventilator can cause barotrauma - piston or pneumatic
- Piston ventilator
- delivery of tidal volumes
- fresh gas flow with the ventilator
Piston Ventilator:
- The piston will ___ extrinsic peep to the anesthesia circuit.
- Breathing bag incorporated into vent circuit during MV. Bag inflates during ___ and deflates during ___.
- If breathing bag rapidly deflates suspect a ___.
- The piston won’t move when patient initiates ____ while on the vent.
- will NOT add extrinsic PEEP
- inspiration, expiration
- circuit disconnect
- spontaneous breaths
What is the most common cause of low circuit pressure?
-Any electronic monitor that detects a circuit disconnect will have a delay!!! If all have some degree of delay which is the shortest???
Circuit disconnect (usually at the Y piece)
During a general anesthetic with an ETT, the high peak pressure alarm sounds. After changing the bag selector switch from ventilator to bag mode, the peak inspiratory pressure returns to baseline. What malfunction is most likely responsible for the rise in peak inspiratory pressure?
Ventilator spill valve malfunctioned
High Pressure in Circuit:
- First rule out patient related causes, chief concern is ____.
- Attempt to manually ventilate as you rule out these causes. Since the ____ improved immediately upon removing the patient from the ventilator, bronchospasm was unlikely.
- Bronchospasm
- PIP
High Pressure in Circuit:
-If you remove the patient from the ventilator and the PP returns to baseline, most likely explanation is the ____ failed. This valve functions to vent excess fresh gas from the flowmeter to the scavenger. If the valve malfunctions fresh gas therefore has nowhere to go, resulting in high circuit pressures.
-Ventilator spill valve failed
High Pressure in Circuit:
If you removed the patient from the ventilator and the circuit pressure remains elevated, the most likely cause is that the ____ or that the ____ on the scavenger has failed. For both you must remove the scavenger transfer tubing from the APL valve. If you can’t do this or this does not relieve the high pressure, remove the patient from the breathing circuit and ventilate with an AMBU bag and begin TIVA.
- scavenger is occluded
- positive pressure relief valve on the scavenger has failed
