Anesthesia Machine Flashcards
2 types of vaporizer Temperature compensation
- Thermocompensation
2. Supplied heat
What color are oxygen tanks?
green
Function of the vaporizer
facilitates the change of a liquid anesthetic into its vapor and add a controlled amount of this vapor to the fresh gas flow.
the operating pressure of the pipeline gas supply is _______ psig
50-55
T/F
Oxygen is wet when it comes out of the cylinder
F
____________ use unique pin and receptacle combinations on cylinder hanger yokes to prevent
the misconnection of a gas cylinder to the wrong cylinder inlet.
Pin Index Safety System (PISS) Connections
_____: This is the junction where the gas emerging from each flow meter must be joined together.
manifold
The flowmeter will function correctly if the tube is _______
vertical
Structural components of the high-pressure system (4)
- gas source
- pressure regulator
- flow control valve
- oxygen flush
function of the breathing bag
allows accumulation of fresh and expired gases during expiration
3 Methods of vaporization
- Flow over
- Bubble through
- Injection
The scavenging system can be composed of the following: (3)
- Gas collecting assembly
- Interface
- Disposal system
_______: collects excess gas from the breathing system and transports it to the waste gas evacuation system
scavenging system
What color are N2O tanks?
blue
2 types of vaporizer specificity
- Agent specific
2. Multiple agent
When a anesthetic machine is attached to both pipeline gas and the gas cylinder is turned on, what would the machine preferably use the pipeline gas?
Pipeline gas runs at 50 psig while the gas cannisters run at 45 psig. The pressure difference causes the machine to preferably use the pipeline gas.
________ breathing system: with reservoir for anesthetic gas mixture, complete rebreathing of expired gas without the CO2 (CO2 removed by soda lime or baralyme in a canister).
closed
Components of the low pressure system
- flow meter
- manifold
- vaporizer
- fresh gas outlet (common gas outlet)
Features of a precision vaporizer (5)
- concentration calibrated (variable bypass)
- flow over
- thermocompensated,
- agent specific
- high resistance.
Liquid oxygen is less _______ and preferred when ________
- expensive
- large amounts of oxygen are needed
The amount of gas remaining in an E-cylinder is directly proportional to its ______
pressure
_______ separates the high-pressure system from the low-pressure system
flow control valve
______exists as a liquid when compressed in a cylinder
N2O
the ________ safety system can be defeated by pulling out the pins or by placing extra washers between the hanger yoke and the cylinder stem
Pin Index Safety System (PISS) Connections
________: provides direct connection between the high-pressure system and the breathing system and bypasses the vaporizer
oxygen flush valve
______: where an O2 and anesthetic gas mixture are blended
low-pressure system
___________ is accomplished by using different sizes of body, nipple, and nut for different gases
Diameter Index Safety System (DISS) Connections
Precision vaporizers for _______ and ______ are the most commonly used in practice.
- isoflurane
- sevoflurane
The indicator or float of a flowmeter is read at the ____ except for the ____ type, which is read in the ______
- top
- ball
- center
Characteristics of “old” or exhausted soda lime (4)
- Hard and chalky
- Color turns blue/violet with exhaustion (if ethyl violet is used as the pH sensitive dye)
- CO2 canister stays cool during anesthesia
- Slightly salty taste (Again, do not attempt to taste it.)
______ tanks are green
oxygen
3 disadvantages of a non-rebreathing system
a. Very high gas flow needed in mL/kg/min and higher anesthetic consumption especially in bigger animals
b. Inspired gas is not humidified leads to a greater loss of body heat
c. More pollution of the environment
the _______ carries the gas mixture and attaches to the breathing system.
fresh gas outlet (common gas outlet)
_________ releases excess gases to the atmosphere and provides the connection to the scavenging system
Adjustable pressure limiting valve (popularly known as the pop-off valve)
2 features of non-rebreathing systems
- The non-rebreathing systems provide less dead space than circle breathing systems
- The non-rebreathing systems provide less or no resistance to breathing compared with the circle breathing systems.
hypoxic gas is defined as inspired O2 concentration below _____%
21%
3 functions of the interface
- prevents the transfer of pressure changes in the scavenging system to the breathing system
- provides positive pressure relief to protect the patient from occlusions of the scavenging system
- provides negative pressure relief to limit the pressure effects of an active disposal system
The safety features of the high pressure system are designed to prevent ______________
delivery of hypoxic gas to the patient
function of unidirectional valves
ensures that gases flow toward the patient in one breathing tube and away in the other breathing tube
in a _________ an internal tube supplies fresh gases to the patient end of the system minimizing mechanical dead space
Bain Coaxial System
Characteristics of fresh soda lime (4)
- Crumbles easily
- White
- CO2 canister feels warm during anesthesia
- Bitter taste (Do not taste it though. It is corrosive when swallowed.)
_______ breathing system: no reservoir for anesthetic gas mixture and no rebreathing of expired gas
open
__________ allow faster connection of gas supply hoses to the pipeline outlets than do the DISS connectors
Quick Connectors
in _______ specificity of the connectors is based on matching the pins and holes
Quick Connectors
What are the 2 sizes of gas tanks? Which is larger?
- H and E
- H
________: delivers the anesthetic gas mixture to the patient
breathing system
Characteristics and features of a good precision vaporizer
Produces accurate anesthetic concentrations over a range of gas flows of 300 ml/min to 10.0 liters/min
b. Has reliable temperature compensation mechanism
c. Able to compensate for changes in pressure, e.g., pressure transmitted to the vaporizer during positive pressure ventilation
d. Presence of keyed filler systems to prevent use of the wrong liquid anesthetic
When the pressure in a N2O tank begins to drop, the content is about _____% of a full tank. After this point, the pressure correlates directly with the volume remaining
25%
______: a three-way tubular connector which connects the inspiratory and expiratory sides of the system to the patient
Y-piece
_________ measures the flow of gas emerging from the flow control valve
flowmeter
The use of oxygen flush should be reserved for use in ____________
recovery when using a rebreathing system (circle) to rapidly replace the gas in the breathing bag when it is emptied to expedite the reduction in the anesthetic concentration in the circuit
__________ breathing system: with reservoir for anesthetic gas mixture, partial rebreathing of expired gas and with CO2 absorption
semiclosed
2 methods of regulating output concentrations in vaporizers
- Concentration calibrated or variable bypass
2. Measured flow or kettle-type
2 types of vaporizer resistance
- Plenum
2. Low resistance
_______: source of the dead space in a circle breathing system
Y-piece
________: with reservoir for anesthetic gas mixture, no rebreathing of expired gas and without CO2 absorption
semiopen
3 safety features that may be used in the high pressure system
- Diameter Index Safety System (DISS) connections
- Quick Connectors
- Pin Index Safety System (PISS) Connections
the ______allows maintenance of constant flow as cylinder pressure changes. It prevents
flowmeter fluctuations
pressure regulator
2 types of gas sources
- pipeline gas supply
- cylinders of compressed gas
function of the breathing system
to deliver the anesthetic gas mixture to the patient
components of circle breathing systems (7)
- CO2 absorber
- Unidirectional valves
- Breathing bag (reservoir bag)
- Breathing tubes and Y-piece
- Pressure gauge
- Negative pressure relief valve
- Adjustable pressure limiting valve (popularly known as the pop-off valve)
N2O is compressed at _____ psig and O2 is
compressed at ______ psig
- N2O : 745 psig
- O2 : 2200 psig
6 characteristics of vaporizers
- location
- method of regulating output concentrations
- method of vaporization
- temperature compensation
- specificity
- resistance
How do you determine the appropriate breathing bag size for a patient?
6 times the tidal volume
Tidal volume = 10-15 ml/kg
Choose the bag that is equal or slightly bigger, not smaller, than the calculated size.
Oxygen can be stored as liquid at a temperature of ____
-297 degrees C
A full H tank holds about _____ L of oxygen
A full E tank holds about _____ L of oxygen
H - 6,900 L (7,000)
E - 700 L
2 problems associated with circle breathing systems
- Resistance to breathing
- Dead space
___________ is designed to prevent the misconnection of a gas supply hose to the wrong pipeline gas inlet
Diameter Index Safety System (DISS) Connections
2 vaporizer locations
- In the circuit
2. Out of the circuit
Disadvantages of the circle breathing system using a vaporizer out of the circuit
- Expensive vaporizer
- Slow changes in anesthetic concentration because the expired gas dilutes the anesthetic concentration in the breathing circuit
_______ tanks are blue
N2O
________:where the pipeline and cylinder gas supplies are connected; responsible for regulating the pressure
high-pressure system
T/F
Flowmeters are interchangeable between gases
F
4 types of breathing systems
- open
- semiopen
- semiclosed
- closed
_____ exists as a gas when compressed in a cylinder
oxygen
3 advantages of a non-rebreathing system
a. No valves, so low resistance
b. Good control of anesthetic concentration which means that the inspired anesthetic concentration is the concentration set on the vaporizer
c. Less dead space
Advantages of the circle breathing system using a vaporizer out of the circuit (4)
- The output of the vaporizer is not affected by the changes in the ventilation of the patient
- Assisted or controlled ventilation will not greatly increase the inspired anesthetic concentration
- Known anesthetic concentration can be delivered to the patient breathing circuit
- Inspired gas, especially at low fresh gas flow, is humidified resulting in decreased loss of patient’s body heat
