ANESTHESIA MACHINE QUESTIONS & ANSWERS
Identify the components of the low pressure system in the anesthesia machine (select
2)
a. cylinder pressure regulator
b. Oxygen flush valve
c. Flowmeter tubes
d. common gas outlet - Answer -c. Flowmeter tubes
d. common gas outlet
High pressure: cylinder pressure regulator
intermediate pressure: oxygen flush valve
Match the following examples of anesthesia machine/circuit components to their proper
location in the SPDD model
1) Disposal a) Cylinder
2) Delivery b) Vaporizer
3) Supply c) Circle system
4) Processing d) Scavenger - Answer -Disposal= scavenger
Delivery= circle system
Supply= cylinder
Processing= vaporizer
If there is a leak after you install a cylinder, do not be tempted to place more than one
washer b/t the cylinder & the hanger yoke assembly. This may bypass the PISS & allow
the wrong cylinder to be matched up with the wrong hander yoke assembly
The oxygen pressure failure device activates when the: (select 2)
a. FiO2 in the inspiratory limb is less than 21%
b. oxygen pressure in the supply line is less than 20 psi
c. oxygen pipeline crossover with N2O
d. oxygen tank is exhausted - Answer -b. oxygen pressure in the supply line is less
than 20 psi
d. oxygen tank is exhausted
The oxygen pressure failure device monitors O2 pressure (not concentration). It
activates when O2 pressure in the intermediate pressure system falls below 20 psi. By
contrast, the O2 analyzer monitors O2 [ ] in the low pressure system. It alarms when the
FiO2 falls below 21%
, If pipeline pressure fails, the auxiliary O2 tank is open, the O2 pressure failure device
won't activate until O2 pressure from tank is < 20 psi. This explains why you don't want
to leave O2 cylinder open if not using it.
Hypoxia prevention safety device on the anesthesia machine will:
a. prevent a hypoxic mixture if a third gas is used
b. shut off the flow of N2O if the O2 supply pressure is less than 30psi
c. limit the N2O flow to 3x O2 flow
d. alarm if the FiO2 is less than 21% - Answer -c. limit the N2O flow to 3x O2 flow
Hypoxia prevention safety device prevents you from accidentally setting a hypoxic
mixture w/ he flow control valves. It's a pneumatic or mechanical device that limits the
N2O flow to no more than 3x the O2 flow.
Click on the annular space - Answer -The annual space is the area between the widest
area of the indicator float & side wall of the flowmeter.
This is a skirted float, which is read at the top of the float
You are administering air at 1L/min & O2 at 3L/min. Calculate the fraction of inspired
O2. Give as percentage - Answer -80
(1x 21) + (3 x 100)/4= 80.25
The PISS system is used to:
a. prevent the use of wrong gas hose
b. diagram the pathway of gas through the anesthesia machine
c. filter & exchange air in the OR
d. prevent the use of the wrong gas cylinder - Answer -d. prevent the use of the wrong
gas cylinder
The pin index safety system (PISS) prevents wrong cylinder from being attached to
anesthesia machine.
The diameter index safety system (DISS) prevents the wrong gas hose from being
attached to the anesthesia machine
SPDD model describes the pathway of gas through the anesthesia machine
Filtering & exchanging air in the OR is not a function of the anesthesia machine
The bourdon pressure gauge on an oxygen cylinder reads 500psi. If the flow rate is
2L/min, how long will this cylinder provider O2 o the patient. (enter minutes & round to
nearest whole number) - Answer -83-87
Identify the components of the low pressure system in the anesthesia machine (select
2)
a. cylinder pressure regulator
b. Oxygen flush valve
c. Flowmeter tubes
d. common gas outlet - Answer -c. Flowmeter tubes
d. common gas outlet
High pressure: cylinder pressure regulator
intermediate pressure: oxygen flush valve
Match the following examples of anesthesia machine/circuit components to their proper
location in the SPDD model
1) Disposal a) Cylinder
2) Delivery b) Vaporizer
3) Supply c) Circle system
4) Processing d) Scavenger - Answer -Disposal= scavenger
Delivery= circle system
Supply= cylinder
Processing= vaporizer
If there is a leak after you install a cylinder, do not be tempted to place more than one
washer b/t the cylinder & the hanger yoke assembly. This may bypass the PISS & allow
the wrong cylinder to be matched up with the wrong hander yoke assembly
The oxygen pressure failure device activates when the: (select 2)
a. FiO2 in the inspiratory limb is less than 21%
b. oxygen pressure in the supply line is less than 20 psi
c. oxygen pipeline crossover with N2O
d. oxygen tank is exhausted - Answer -b. oxygen pressure in the supply line is less
than 20 psi
d. oxygen tank is exhausted
The oxygen pressure failure device monitors O2 pressure (not concentration). It
activates when O2 pressure in the intermediate pressure system falls below 20 psi. By
contrast, the O2 analyzer monitors O2 [ ] in the low pressure system. It alarms when the
FiO2 falls below 21%
, If pipeline pressure fails, the auxiliary O2 tank is open, the O2 pressure failure device
won't activate until O2 pressure from tank is < 20 psi. This explains why you don't want
to leave O2 cylinder open if not using it.
Hypoxia prevention safety device on the anesthesia machine will:
a. prevent a hypoxic mixture if a third gas is used
b. shut off the flow of N2O if the O2 supply pressure is less than 30psi
c. limit the N2O flow to 3x O2 flow
d. alarm if the FiO2 is less than 21% - Answer -c. limit the N2O flow to 3x O2 flow
Hypoxia prevention safety device prevents you from accidentally setting a hypoxic
mixture w/ he flow control valves. It's a pneumatic or mechanical device that limits the
N2O flow to no more than 3x the O2 flow.
Click on the annular space - Answer -The annual space is the area between the widest
area of the indicator float & side wall of the flowmeter.
This is a skirted float, which is read at the top of the float
You are administering air at 1L/min & O2 at 3L/min. Calculate the fraction of inspired
O2. Give as percentage - Answer -80
(1x 21) + (3 x 100)/4= 80.25
The PISS system is used to:
a. prevent the use of wrong gas hose
b. diagram the pathway of gas through the anesthesia machine
c. filter & exchange air in the OR
d. prevent the use of the wrong gas cylinder - Answer -d. prevent the use of the wrong
gas cylinder
The pin index safety system (PISS) prevents wrong cylinder from being attached to
anesthesia machine.
The diameter index safety system (DISS) prevents the wrong gas hose from being
attached to the anesthesia machine
SPDD model describes the pathway of gas through the anesthesia machine
Filtering & exchanging air in the OR is not a function of the anesthesia machine
The bourdon pressure gauge on an oxygen cylinder reads 500psi. If the flow rate is
2L/min, how long will this cylinder provider O2 o the patient. (enter minutes & round to
nearest whole number) - Answer -83-87
