Anesthesia Gas Machine

Front 1

How do gases come to the anesthesia machine?

Back 1

Pipeline- wall outlets, connecting valves and hoses, filers and check valves, pressure gauges

Cylinders- hanger yolks, filters and check valves, pressure gauge, pressure regulators

Front 2

how does the anesthesia gas machine prepare gases before their delivery to the patient? & what are some aspects of processing?

Back 2

Site:within the machine, proximal to common gas outlet

Failsafe- o2 pressure-failure devices, flowmeters, o2 flush, low o2 alarms, venilator driving gas, proportioning systems (hypoxic gaurd), vaporizers, common gas outlet

Front 3

how is the interaction of gases with the patient controlled and monitored?

Back 3

(site breathing circit)
gas delivery hose connecting common gas outlet and breathign circit
-carbon dioxide absorber
ventilators
integral monitors (o2 analysis, disconnect, spirometer, capno, airway pressure, vent alarms)
-Peep
-humidification

Front 4

how are gases disposed of?

Back 4

scavenger system

Front 5

what is the primary gas source pressure and what is a full cylinder pressure?

Back 5

pipeline pressure is 50psi
O2 cylinder pressure full is 2000psi

Front 6

What are required monitors on an anesthesia machine?

Back 6

Exhaled volume
Inspired oxygen, with a high priority alarm within 30 seconds of oxygen falling below 18% (or a user-adjustable limit).
Oxygen supply failure alarm
A hypoxic guard system must protect against less than 21% inspired oxygen if nitrous oxide is in use.
Anesthetic vapor concentration must be monitored.
Pulse oximetry, blood pressure monitoring, and EKG are required

Front 7

what is o2 flush pressure?

Back 7

25-75 L/min

Front 8

How are pipeline linlets connected?

Back 8

Pileline inlets are connected with DISS (diameter index saftey system) non-interchangeable connections.

The check valve (located downstream form the pipeline inlet) prevents reverse flow of gases (from machine to pipeline)

Front 9

What are the colors for o2, no2, and air?

Back 9

o2 green
o2 blue
air yellow

Front 10

Cylinder saftey system?

Back 10

PISS Pin index saftey system prevents misconnection of a sylinder to the wrong yolk.
Use only one washer!!

Front 11

What does the hanger yolk do?

Back 11

Hanger yolk orientes cylinders, provides unidirectional flow and ensures gas-tight seal

Front 12

cylinder pressure regulator converts ___ cylinder pressure to a constant prssure of ___ downstream of the regulator?

Back 12

cylinder pressure regulator converts HIGH cylinder pressure to a constant prssure of 45 downstream of the regulator?

Front 13

Devices and techniques which do NOT rely on wall outlet electrical power include?

Back 13

spontaneous or manually assisted ventilation
mechanical flowmeters
scavenging
laryngoscope, flashlights
intravenous bolus or infusion
battery operated peripheral nerve stimulators or intravenous infusion pumps
monitoring using the anesthetist's five senses

Front 14

In the event of a o2 crossover ( o2/no2) or low o2 pipeline pressure what should the CRNA do ?

Back 14

turnb on backup o2 cylinder and disconnect o2 pipeline supply hose from the wall (because the gas will flow from whichever has the highest pressure, pipeline 50 psi, cylinder 45psi)

Front 15

Does the fail- safe system prevent a hypoxic mixture from being delivered?

Back 15

NO! only the hypoxic gard only connects o2 and no2 flowmeters.
The failsafe ensures the o2 concentration is delivered (pressure)

Front 16

What should you do if you lose o2 pipeline pressure?

Back 16

Same as a crossover! Open the o2 cylinder completely and disconnect the pipeline because it delivers a higher pressure than the cylinder! o2 analyzer should warn of a crossover or the pulse ox will after all o2 is washed out of the FRC! and Ventilate by hand because it uses less o2 than the vent!

Front 17

Proportioning Systems are the board exam terminology for the hypoxic guard system. What do they do?

Back 17

These systems link nitrous oxide and oxygen flows (mechanically, pneumatically, or electronically) to prevent final inspired oxygen concentration less than 0.25.

Front 18

How to eliminate Co2 during anesthesia?

Back 18

 Co2 is eliminated by washout with FGF or soda lime absorption

Front 19

What is vent deadspace for
VD/VT= ____ normally, ___ if intubated ___mask case.

Back 19

Dead space is increased (by all respiratory apparatus). VD/VT= 0.33 normally, 0.46 if intubated and 0.65 if mask case.

Front 20

What is the soda lime activators?

Back 20

NaOh or KOH

Front 21

Capnography has been shown to be effective in the early detection of? (4)

Back 21

adverse respiratory events
malpositioning of ET tube
Circulatory failure
defective breathing circuits

Front 22

True or False? Capnography is the best method to confirm correct placement of the ETT?

Back 22

TRUE

Front 23

PHYSICS: This technique is the most popular for monitoring and analysing gases. It absorbs specific wavelengths.

Back 23

Infra Red Spectrography

(Oxygen does not absorb IR light and is not measured using this technique)

Front 24

What is the correlation between PaCo2 and ETCO2?

Back 24

ETCO2 is 5-10 torr lower than PaCO2
(because ETCO2 is diluted with alveolar deadspace gas from under perfused alveoli)

Front 25

Name some problems with pipeline supply?

Back 25

pressure loss, excessive pressure, cross-connection of delivery pipelines, contamination, leaks

Front 26

True or False? Always trust the oxygen analyser until you can prove it wrong?

Back 26

TRUE

Front 27

what is the function of the pipeline inlet check valve?

Back 27

unidirectional flow
prevents retrograde flow

Front 28

what is the most fragile part of the cylinder?

Back 28

cylinder valve! protect it during transport

Front 29

What are the 3 functions of the hanger yolk?

Back 29

orientes cylinders, provides a gas-tight seal, ensures unidirectional flow

Front 30

What will happen if the oxygen cylinder is left open after checking it and pipeline pressure fails?

Back 30

Nothing, the operator will not be alerted to the failure because gas will simply begin to flow from the cylinder due to it becoming the higher pressure.

Front 31

Which reglitory agency issues regulations for the manufacture, handling, transport, storage and disposal of cylinders?

Back 31

Department of transportation

Front 32

name 4 circumstances can permit a hypoxic mixture even when the hypoxic gaurd system is employed?

Back 32

1. wrong supply gas in oxygen pipeline or cylinder
2. defective pneumatics or mechanics (hypoxic gaurd system is broken)
3. leaks downsteram of flowmeter control valves
4. inert gas administration (third gas such as helium administration)


O2 analyzer is of great importance!!!!

Front 33

Name the only system that ensures that oxygen is present

Back 33

ONLY ONE SYSTEM that ensures that oxygen is present in the oxygen pipeline or cylinder: the inspired oxygen analyzer

supply failure alarms warn of trouble with o2 supply & hypoxic guard and fail-safe systems lessen the chance of hypoxemia but are based on pressure within the system. They do not sample the lines to determine that o2 is present.

Front 34

Does a face mask or ett have greater deadspace?

Back 34

face mask

Front 35

Where does deadspace end?

Back 35

Deadspace ends where the inspiratory and expiratorygas streams diverge. in a circle system this is the y piece

Front 36

Can you have a semi-open classicication with a circle system?

Back 36

yes, at high fresh gas flow (more than minute ventilation) or with the use of a nonrebreathing circuit

Front 37

for a closed breathing circuit the flow should be (high/low) and the APL valve should be ____?

Back 37

for a closed breathing circuit the flow should be HIGH and the APL valve should be CLOSED?

Front 38

4 common reaturs of nonrebreathing systems

Back 38

NO UNIDIRECTIONAL VALVES
NO SODALIME/ CO2 ABSORPTION
REBRETHING IS HIGHLY DEPENDENT ON FGF
LOW RESISTENCE

Front 39

NAME 3 NON-REBREATHING (semi-open) CIRCUITS

Back 39

BAIN
MAPLESON
CIRCLE WITH HIGH FGF (GREATER THAN MINUTE VENTILATION)

Front 40

2 causes for increase in inspired co2?

Back 40

exhaused co2 absorber
unidirectional valves are faulty

Front 41

if inspired co2 on the capnogrophy is 1-3 mmhg what can be done?

Back 41

increase FGF to 5-8L (this converts the closed system to a semi-open and minimized rebreathing of exhaled gases.

Front 42

How do you check the unidirectional valves?

Back 42

place a reservoir bag on the y piece and mechanically ventilate watching the valves.

or
occlude one side at a time and breath into the unidirectional tubing. should only be able to expire not inspire on the expiratory limb and viseversa

Front 43

carbon monoxide is most common with which agent____ and with a __dry/moist__ absorbant?

Back 43

carbon monoxide is most common with des and with dry absorbent.

it is recommended that o2 be turned off at the end of each case to keep grandules moist.

Front 44

Carbon dioxide absorbers recommendations?

Back 44

1.turn off all gases when not in use
2. change absorbent regularly
3. change both canesters not just one
4. change absorber if hydration state unknown of if gas left on overnight/weekend
5. low flows preserve humidity, dry absorbent exhausts quickly

Front 45

2 examples of open breathing systems?

Back 45

nasal canula
open drop ether

Front 46

this type of breathing system has a minumum FGF of 5L/min

Back 46

semi-open. 5L/Min required to prevent rebreathing
the FGF exceeds minute ventilation 2-3 times

Front 47

this is a version of the mapleson D with 200-300cc/kg/min for spontenaous and 70cc/kg/min for controlled

Back 47

Bain

Front 48

describe the bain system including the tube, where FGF enters, and FGF required for spontenous and controlled ventilation

Back 48

bain system is a coaxial tube (tube within a tube)
FGF enters though a narrow inner tube
FGF to prevent rebreathing 200-300ml/kg/min with sponteneous breathing and 70mg/kg/min with controlled vent.

Front 49

name advantages of bain system

Back 49

warming and humidification of gases
ease of scavenging
APL valve
disposable

Front 50

does the semiclosed circle system allow for rebreathing of exhaled gases?

Back 50

partial

Front 51

does the semiclosed circle system have sodalime?

Back 51

yes

Front 52

true or false, semiclosed circle system has a higher FGF than minute ventilation?

Back 52

false, FGF is less than minute ventilation

Front 53

name the 7 components of the semi-closed circle system

Back 53

FGF
inspiratory and expiratory unidirectional valves
insp aind exp corrugated tubes
y piece
apl
reservoir bag
co2 absorbent

Front 54

name 3 advantages to a semi-closed circle system

Back 54

consistancy of inspired concentration
concserves resp moisture
minimal pollution (scavenging)

Front 55

What is the APL valve

Back 55

limits the amount of pressure build up that can occure during manual ventilation

Front 56

if you have no air in you resevior bag is you pop off valve open or closed

Back 56

open

Front 57

what is the reaction with a co2 absorber?

Back 57

a BASE neutralizing an ACID

Front 58

name 3 endproducts of CO2 absorber reaction

Back 58

heat, water, carbonate

Front 59

what is the mesh size of the granules for co2 absorber

Back 59

4-8 mesh. higher the number smaller the granule

Front 60

carbon monoxide production increases with (4)

Back 60

des (and other agents)
low fresh gas flows
high concentrations of agents
dry absorbent

Front 61

what is the nitrous oxide cylinder pressure when full

Back 61

745psi

Front 62

what does the failsafe gaurd against?

Back 62

decrease oxygen pressure
if pressure is lost the failsafe shuts off the flow of all other gases. can NOT DETECT A CROSSOVER

Front 63

what does the hypoxic gaurd?

Back 63

works on oxygen pressure. it controls the ratio of oxygen and nitrous oxide so that there is a minimum of 25% oxygen. it does not analyze the gas.

Front 64

what 2 devices willl inform you of a crossover of o2 and n2o?

Back 64

FIRST- oxygen analyzer
second- pulse oximeter

Front 65

how do you calculate how long your cylinder will last?

Back 65

contents L/gauge pressure= capacity L/ service pressure

EX: xL/1000psi(whats left in container)= 660L/ 2000psi

answer is in L then divide by however many L/min.

Front 66

2 things that can cause high positive pressure to the patient that are related to the anesthesia machine?

Back 66

obstruction of the scavenger
failure of the ventilator relief valve

Front 67

what is the most common site for disconnecton? and what is the most important monitor for disconnection?

Back 67

common site is y piece
monitors for disconnect: apnea, circuit pressure, co2, acustic sound of ventilator or percordial steth.

Front 68

What is the preferred bellow design and why?

Back 68

descending bellows do not indicate a disconnection and it collects exhaled humidity
ascending is best!!

Front 69

every vent is different, what is the best way to initiate machanical ven

Back 69

switch to bag/vent
make sure the vent starts to cycle (check for chest expansion with the first breathing cycles)
review mode, volume or pressure, and rate settings

Front 70

during an emergency what is the minimum that must be checked even when time is at a premium?

Back 70

1. high pressure test of the breathing circuit (ensure no leaks are present distal to the common gas outlet)
2. when placing the mask on the patients face to rpe-oxygenate them always observe or palpabe the breathing bag for fluctuation (flow)
3. check suction

Front 71

what is the best way to preoxygenate?

Back 71

4-6L/min FGF
apl fully open
tight mask
3-5 min of TB or 4-8 vital capacity

Front 72

what is the threshold for smelling volatile agents and what is the NIOSH standard concentration amount?

Back 72

smelling agents 5-300ppm and standard is not more than 2ppm

Front 73

if you can smell an agent what should you do? what are the causes?

Back 73

poor mask fit
unscavenging technique such as insufflation
agent on before mask is on patient
spilled agent
uncuffed tracheal tube
machine leak
increase scavenger

Front 74

if your fgf is 4L/min how much is scavenged per minute

Back 74

must be the same amount or else barotrauma

Front 75

this system consists of a NEEP and PEEP relief valve

Back 75

scavenging system

Front 76

This alarm system detects disconnects, major air leaks, leaking tracheal cuff and failure to cycle

Back 76

LOW PRESSURE ALARM
This alarm system detects disconnects, major air leaks, leaking tracheal cuff and failure to cycle

Front 77

This alarm system detects airway obstruction, laryngospasm, decreased lung compliance (bronchospasm), kinked or occluded ETT, patients coughing against ETT, occlusion of expiratory limb

Back 77

HIGH PRESSURE ALARM
This alarm system detects airway obstruction, laryngospasm, decreased lung compliance (bronchospasm), kinked or occluded ETT, patients coughing against ETT, occlusion of expiratory limb

Front 78

This alarm system detects NG tube in the trachea, blocked inspiratory limb, malfunctioning scavenging system, inhalation against an empty reservoir bag

Back 78

SUB-AMNIENT PRESSURE
This alarm system detects NG tube in the trachea, blocked inspiratory limb, malfunctioning scavenging system, inhalation against an empty reservoir bag

Front 79

The apnea pressure alarm limit should be adjusted as close as possible to the patients ____ without exceeding it?

Back 79

PIP
because... if threshold is too low it will not detect partial breathing, leaks, or disconnect. ALARM WILL NOT SOUND.

Front 80

When preoxygenating your patient what should your FGF be? APL valve?

Back 80

8-10 L and APL should be OPEN

Front 81

3 Pressure relief valves for cylinders? (can have one or more of the following)

Back 81

fusible plug (thermally operated)
frangible disc (burst with high pressure)
safety relief valve (opens under high perssure)

Front 82

what is the fail-safe valve and where is it located?

Back 82

controlled by oxygen poressure, it senses a drop in o2 pressure (below 12-30) and (shuts off or proportionaly decreases supply of N2O.
Located in-line between the N2O supply and the flowmeter

(can not sense a crossover)

Front 83

what is the fail-safe valve and where is it located?

Back 83

controlled by oxygen poressure, it senses a drop in o2 pressure (below 12-30) and (shuts off or proportionaly decreases supply of N2O.
Located in-line between the N2O supply and the flowmeter

(can not sense a crossover)

Front 84

Give examples of ways the the fail-safe system helps prevent hypoxia?

Back 84

disconnects, low 02 pressure in pipeline, depletion of o2 cylinders

EX: disconnect the o2 and the No2 shold decrease to zero

Front 85

Give examples of ways the the fail-safe system helps prevent hypoxia?

Back 85

disconnects, low 02 pressure in pipeline, depletion of o2 cylinders

EX: disconnect the o2 and the No2 shold decrease to zero

Front 86

Where is the oxygen analyzer positioned?

Back 86

inspiratory limb

Front 87

Where is the oxygen analyzer positioned?

Back 87

inspiratory limb

Front 88

what is part of the low pressure system?

Back 88

vaporizers, common gas outlet, flowmeters

Front 89

what is part of the low pressure system?

Back 89

vaporizers, common gas outlet, flowmeters

Front 90

Where is the hypoxic gard system located?

Back 90

flowmeters, minimum oxygen ratio device, actively increases o2 when n2o is increased

Front 91

Where is the hypoxic gard system located?

Back 91

flowmeters, minimum oxygen ratio device, actively increases o2 when n2o is increased