Anesthesia Equipment & Technology(test 1) Flashcards
What is the minimum thickness for a gas cylinder?
0.26 inches
What is the capacity of an E cylinder of oxygen?
660 liters
What is the capacity of an E cylinder of nitrous oxide?
1590 liters
What does a fusible plug offer protection from and what does it not offer protection from?
it offers protection from EXCESSIVE PRESSURE, but not from OVERFILLING
What does a rupture disc offer protection from?
it offers protection from both high temperature and from overfilling
How often must gas cylinders be inspected?
every 5 years
What are 3 safety systems that are used to avoid incorrect gas connections?
cylinder color coding
pin indexing
diameter indexing
At what psi should an oxygen cylinder be changed?
1000 psi
What is the full cylinder pressure for oxygen?
2200 psi
What is the full cylinder pressure for air?
2200 psi
What is the full cylinder pressure for nitrous?
745-750 psi
Pipelines are used to deliver what 5 nonflammable gases?
oxygen, nitrous oxide, air, carbon dioxide and nitrogen
What is the most common contaminant of medical gas lines?
water
In what 2 forms can oxygen be stored in?
as a cryogenic liquid at low pressures or as compressed gas in cylinders
Purity of medical gases is specified in the _____?
US Pharmacopeia
Purity of medical gases is enforced by who?
the Food and Drug Administration
What three agencies have published standards regarding gas cylinders?
Department of Transportation(DOT)
National Fire Protection Association
Compressed Gas Association
What is the most common cause of a leak in a new gas cylinder?
a missing or defective washer
What safety system is used to help prevent incorrect connections between central pipeline connection and the anesthesia machine?
diameter indexed safety system(DISS)
What psi is cylinder gas reduced to by a regulator upon entering the anesthesia machine?
50 psi
What are 3 hazards in gas pipeline systems?
leaks
fires
cross-connections
At what level does pipeline alarms indicate a change?
if there is an increase or decrease in pressure by 20% from normal
What regulatory body covers anesthesia workstations and their components?
The American Society for Testing and Materials(ASTM)
How often should computer-driven anesthesia machines be turned off and restarted?
every 24 hours
What are the only things that should be plugged into the anesthesia machineās electrical outlets?
Only the anesthesia monitors
How long should the anesthesia backup battery power last?
at least 30 minutes
When gas travels from the high-pressure cylinder to the machine, a pressure regulator decreases the pressure to what?
50 psig
What are three functions of the hanger yoke on the back of the anesthesia machine?
- orients and supports the cylinder
- provides a gas-tight seal
- ensures unidirectional flow
What components on the anesthesia machine are exposed to high pressure(3)?
- hanger yoke
- cylinder pressure gauge
- cylinder pressure regulators
What is the function of the check valves on the back of the anesthesia machine?
- allows gas to enter the machine
2. prevents gas from exiting the machine when there is no gas cylinder in the yoke
What are cylinder and pipeline pressure gauges?
metal needles which stretch with pressure and point to correct pressure(Bourdon gauges)
What are the three pneumatic components of the intermediate pressure system?
- master switch
- oxygen failure devices
- flow control devices
What 4 accessories on an anesthesia machine is supplied by oxygen?
- ventilator
- accessory flowmeter
- jet ventilation
- oxygen flush
What does the flush button do on the anesthesia machine and does it require activation of the master switch?
- directs a high unmetered flow directly to the CGO(35-75 LPM)
- it does not require activation of the master switch
What are 4 hazards related to the oxygen flush valve?
- leaks
- sticking and obstructing flowmeter output
- barotrauma
- awareness
At what low oxygen supply pressure does the machine alarm by either an electronic or pneumatic alarm?
30 psig
What is the function of the āfail-safeā valve(oxygen pressure sensor shut-off valve)?
it will decreased supply pressure of other gases as the oxygen supply pressure decreases(i.e.,below 20-25 psig).
What is the function of reducing devices just upstream of flow valves?
they decrease gas pressure a second time to 15 - 19 psig
What 4 machine components are exposed to the low pressure system on the anesthesia machine?
- flowmeter tubes
- vaporizers
- check valves
- common gas outlet
What is the most common means of regulating flowmeter rate?
it is a needle valve
Name and describe traditional flowmeters
traditional flowmeters are Thorpe tubes, vertical glass tubes tapered with its smallest diameter at the bottom.
Physical properties of the gas affect the flowmeter indicator and includeā¦.(4)?
- viscosity
- density
- weight of the float
- annulus of the tube
How are flowmeters distinguished between the gases?
flowmeters are color coded and the flow control knob for oxygen is larger and shaped differently
Where are Bobbin flowmeters read from?
from the top
Where are ball float flowmeters read from?
from the middle
What are 3 factors affecting flowmeter accuracy?
- back pressure from a ventilator
- static electricity/dirt
- a float stuck at the top of the Thorpe tube
Should the common gas outlet be used to administer supplemental oxygen to a patient?
NO!
What are the 4 components in the high pressure flow system?
- hanger yoke
- yoke block with check valves
- cylinder pressure gauge
- cylinder pressure regulators
What are the 6 components in the intermediate pressure flow system?
- ventilator power inlet
- pipeline inlets, check valves, pressure gauges
- flow meter valves
- oxygen pressure-failure devices
- oxygen second stage regulator
- flush valve
What are the 4 components in the low pressure flow system?
- flow meter tube
- vaporizers
- check valves
- common gas outlet
Modern vaporizers are accurate over a wide range of ___and ___ ___ ___.
temperatures
fresh gas flows
What is a measure of the volatility of the liquid anesthetic in the carrier gas?
SVP
What is the definition of heat of vaporization?
its the amount of calories required to convert 1 g of liquid to vapor without temperature change in the remaining fluid.
What is being referred to when one speaks of a substanceās specific heat?
its the quantity of heat required to raise the temperature of 1 gram(1 ml) of a substance by 1 degree C.
What are 4 factors that can potentially affect vaporizer output?
- FGF
- temperature
- carrier gas composition
- ambient pressure
What does increased contact area between gas and liquid in the vaporizer increase?
it increases the efficiency of vaporization(baffles, spiral tracks or wicks).
What are 3 characteristics of modern vaporizers?
- agent-specificity(keyed filling port required)
- temperature compensation
- flow-over
What is the function of the vaporizer interlock system?
its a safety feature that only allows one vaporizer on at a time.
What is the basic operating premise of a variable-bypass vaporizer?
it states that FGF enters the vaporizer and splits into carrier gas(much less than 20%) and bypass gas(80%)
What is the āsplitting ratioā of the two flows of the variable-bypass vaporizer dependent upon?
The āsplitting ratioā of the two flows depends on the ratio of resistances to their flow(determined by concentration dial). Output is relatively constant over a wide range of flows(250 ml/min to 15 L/min)
What does the āpumping effectā describe in relation to the breathing system?
āPumping Effectā describes the affect on on vaporizer output from intermittently fluctuating pressure in the breathing system.
What 4 standards did the ASTM establish in 1988?
- FGF limits(15 L/M)
- unidirectional rotation for concentration increase
- concentration calibration of vaporizers
- temperature/pressure effects
What are 4 hazards associated with vaporizers?
- using the wrong agent
- tipping
- overfilling
- empty vaporizer
What are 3 safety features of modern-day vaporizers?
- agent specific keyed fillers
- secured vaporizers
- interlocks
- counterclockwise rotation of dial for increase in concentration
In relation to FGF what are 2 difference between a Tec 5 vaporizer and the newer model vaporizers(Tec 6, 7, ect.)?
- Tec 5 vaporizer require FGF close to 5 LPM
2. is more affected by pumping
What happens to the temperature of Desflurane as large amounts of it is vaporized?
Desflurane is heated to 39 degrees(above boiling point) as large amounts are vaporized and over pressurized to 1300 mmHg.
Where is the electronic control mechanism at in the Aladin cassette?
The electronic control mechanism in the Aladin cassette is in the anesthesia machine.
Can the Aladin cassette be tipped?
YUP!
Vapor 2000 vaporizers may be tipped as long as they are in the ___ setting.
āTā
What should you do if the wrong agent is used to fill the vaporizer?
If the wrong agent is used, discard contents of vaporizer and run 5 liters oxygen flow until no agent is detected(about 20 minutes).
Of the following accessories which are supplied by oxygen? Oxygen flush Vaporizer interlock Scavenger All of the above
Oxygen flush
An āEā cylinder of oxygen completely filled should hold?
660 liters
A factor potentially affecting vaporizer output is: fresh gas flow temperature carrier gas composition all of the above
all of the above
Pipelines are used to deliver all of the gases below except:
oxygen
nitrogen
carbon dioxide
all of the above are delivered by pipeline
all of the above delivered by pipeline
What is an example of a cylinder pressure gauge(metal needles that stretch with pressure)?
bourdon gauge
Flush buttons direct 35 - 75 ppm directly to the: high pressure system intermediate pressure system scavenger common gas outlet
common gas outlet
What is used to prevent incorrect connections between the pipeline and the anesthesia machine?
diameter index safety system
Safety features of vaporizers include: empty vaporizer alarms vaporizer interlocks clockwise rotation of concentration ideals for increased output all of the above?
vaporizer interlocks
What is the minimum thickness for a gas cylinder?
0.26 inches
What describes the effect on vaporizer output from intermittently fluctuating pressure in the breathing circuit?
Pumping effect
The _____ _____ of carrier gas and bypass gas depends on the ratio of resistances to their flow(determined by the concentration dial and the temperature compensation device).
splitting ratio
The basic operating premise of variable bypass vaporizers states that fresh gas flow enters the vaporizer and splits into carrier gas and bypass gas. Carrier gas is approximately what percentage of fresh gas flow?
20%
Oxygen tanks should be changed when the service pressure is how much?
less than 1000 psi
Gas cylinders must be inspected every?
5 years
Which of the following anesthesia machine components is exposed to high pressure?
hanger yoke
cylinder pressure gauge
cylinder pressure regulators
all of the above?
all of the above
Purity of medical gases is specified by who?
U.S. Pharmacopeia
The most common contaminant of medical gas pipelines is?
water
Desflurane is heated to ____ and pressurized to ___ to compensate for a low boiling point and high vapor pressure.
39 degrees celsius and 1300 mmHg
What device offers protection from excessive pressure from high temperature but not from overfilling?
fusible plug
When gas travels from the cylinder to the machine, a regulator decreases pressure to
45 - 55 psi
Machines possess a pneumatic or electronic alarm device that sounds a warning when the pressure is below?
30 psi
What is the measure of the volatility of a liquid anesthetic in a carrier gas?
Saturated Vapor Pressure
Hazards in pipeline systems include:
cross-connections
leaks
fires
all of the above
all of the above
What is the term used to describe the amount of calories required to convert 1 G(ml) of liquid to a vapor without temperature change in the remaining fluid?
Heat of vaporization
Hazards associated with vaporizers include:
use of the wrong agent
tipping
overfilling
all of the above
all of the above
Which statement best describes the hypopharynx?
a. Adenoids and openings to Eustachian tubes are found here
b. Level C23 location
c. Also known as oropharynx
d. Lowermost portion of pharynx, which leads to esophagus and larynx, extending down
into trachea
d. Lowermost portion of pharynx, which leads to esophagus and larynx, extending down
into trachea