Westminster Machine 2

Front 1

The Electric System [5]

Back 1

Master switch
Power failure Indicator
Backup power (battery)
Electric outlets
Circuit breakers

Front 2

Floating (check) valve:

Back 2

Move whichever way pressure is pushing.

Front 3

Diaphragm valve:

Back 3

Turning the stem raises or lowers the flexible diaphragm and seals the opening to internal parts.

Front 4

Flutter valve:

Back 4

Inspiration/Expiration check valves, unidirectional

Front 5

Flow control (needle/pin/fine adjustment/flow adjustment) valve:

Back 5

Controls the rate of flow of a gas through its associated flow indicator by manual adjustment of a variable orifice. One/gas.

Front 6

APL (pop of):

Back 6

Adjustable pressure limiting valve. Adjustable knob and mechanism with spring control placement of diaphragm in valve seat to regulate how much anesthesia gas enters into gas scavenging system.

Front 7

Spring disc (ball) valve:

Back 7

A spring holds the disc against the seat. When pressure on the disc is great enough to overcome the force of the spring, the valve opens. Flush valve, all or none.

Front 8

Check Valves: 3 main functions

Back 8

1) Prevents “back-flow” from high-pressure to low-pressure sides; prevents “pumping action” of gases. Pumping action is generated by positive pressure ventilation or by intermittent pressing and releasing of the O2 flush valve, especially when running low flows, the net result was an increased concentration of anesthetic being delivered. New vaporizers have a decreased size of vaporizing chamber and an increased volume in the inflow channel.

2) Allows for an empty cylinder to be exchanged for a full one with minimal loss of gas

3) Minimizes leakage from an open cylinder to the atmosphere

Front 9

The Pneumatic System
3 Systems

Back 9

High Pressure

Intermediate Pressure

Low Pressure

Front 10

High Pressure System

Hanger Yoke

Back 10

Body, Filter
Retaining screw
Nipple
Index pins on yoke
Washer
Check valves in hanger yoke
Check valve assembly
Cylinder pressure gauges

Front 11

High Pressure System[4]

Back 11

Hanger yoke
Cylinder Pressure Indicator (gauge)
Pressure-reducing device (regulator), 1st stage, diaphragm valve
Woods metal: bows with high heat (200 C.) to let gas out slowly

Front 12

Intermediate Pressure System [10]

Back 12

Pipeline inlet connections
Pipeline pressure Indicators/gauges
Piping
Gas power outlet
Master switch (pneumatic component)
Flush valve
2nd stage regulator, psig 40-50 drops to 16 psig
“Fail safe” shut off valve
DISS: diameter indexed safety system
Flow control valve of manifold has the greatest fluctuation in pressure

Front 13

Intermediate Pressure System

DISS: Diameter Indexed Safety System [6]

Back 13

1) Quick push-on connectors
2) indexed for a specific gas
3) 40-50 ppsi for O2/N2O
4) Check valve in pipeline inlet assembly is a floating valve and seats according to pressure
5) On back of gas machine
6) Power outlet valve is ball & spring valve

Front 14

02 tank

Hanger Yolk Valve: [4]

Back 14

1) In yolk assembly and has pins for E cylinders to fit on. The O2 pin index is 2,5 & N2O is 3,5
2) Acts as a safety valve
3) Opens/closes with pressure,
“free floating valve”
4) Prevents a full cylinder from emptying into an empty cylinder and from wall oxygen from entering a cylinder

Front 15

02 tank

Oxygen cylinder pressure regulator (first stage regulator) [3]

Back 15

1) Cylinder pressure decreased to 40-50 ppsi
2) Serves both yolks
3) This is a diaphragm valve

Front 16

Intermediate Pressure System functions [3]

Back 16

1) Check valve between vaporizer outlet and machine outlet (not present on all machines)
Prevents reversal of flow
Diaphragm type valve (stifffer)
2) Inspiration and Expiration valve (flutter valves)
3) Permits direction of gas flow to and from the patient
(unidirectional)
- Opening is limited by a retainer

Front 17

Intermediate Pressure System

Oxygen flow meter and flow control valve

Back 17

Deliver gas to patient circuit
Receives low pressure gas (16 psi)Oxygen flow meter and flow control valve
Deliver gas to patient circuit
Receives low pressure gas (16 psi)
Needle valve
The thorpe tube is gas specific and tapered with largest diameter at the top

Front 18

Intermediate Pressure System
\Oxygen pressure failure devices (Oxygen failure safety device)

Back 18

Senses oxygen pressure at 50 psi
Shuts off N2O
O2 must maintain at least 25 psi on the diaphragm to keep the valve open
Pin and spring valve
Senses pressure only, not flow delivery
Fluted knobs

Front 19

Intermediate Pressure System

Oxygen supply failure alarm

Back 19

Electronic alarms
Pneumatic alarms

Front 20

Intermediate Pressure System


Oxygen flush valve;

Back 20

O2 is delivered directly to the patient at a rate of 35-75 l/min. This will dilute the anesthetic gases. Can cause barotrauma.

Front 21

Intermediate Pressure System

Gas selector switch:

Back 21

bag vs. ventilator

Front 22

Intermediate Pressure System

Second-stage-reducing device:

Back 22

reduces line pressure and maintains constant flow with changing supply pressures

Front 23

Intermediate Pressure System

-Flow control valves
components [3]

Back 23

-Flow control valves
components
a) Body
b) Stem and seat
c) Control knob

Front 24

Intermediate Pressure System

-Problems with flow control valves

Back 24

a) Inadvertent alterations
b) Inability to turn control knob
c) Leak through open flow control valve
d) Failure to allow adequate gas flow

Front 25

Low Pressure System components [3] [5]

Back 25

1) Vaporizer
2) Common gas oputlet
3) Manifol and check valves, fluctuates the least

Unidirectional (check) valve
Pressure relief device
Low-pressure piping
Vaporizer mounting devices
Common (fresh) gas outlet

Front 26

Low Pressure System

Flow indicators
Physical principles

Back 26

A) Flow indicators
1) Physical principles
Pressure drop across the constriction
Size of the annular opening
Physical characteristics of the gas
Temperature and pressure effects

Front 27

Low Pressure System

Flow indicator blocks

Back 27

Tube
Float
Nonrotating floats
Rotameters
Ball floats
Stop
Scale
Lights
Arrangement of flow indicator tubes
Parallel
Series
Sequence of flow indicator tubes
Safety devices
Mandatory minimum oxygen flow
Minimum oxygen ratio device
Mechanical linkage
Pneumatic linkage
Alarms

Front 28

Low Pressure System

Problems with flow indicators/thorpe tube

Back 28

- Improper assembly or calibration
- Sticking Indicator, large on top, small on bottom
- Back pressure
Problems with the float
Indicator unnoticed at top of tube
Blockage of tube outlet
Reading of wrong flow indicator
Changes in float position
Leaks
Using the wrong flowmeter

Front 29

APL Valve (pop off)

Back 29

Adjusts the limit of pressure in the patient circuit and rebreathing bag
2) Tightening the knob will increase the pressure
3) Attached to exhalation check valve

Front 30

Machine Check

Nine parameters that the anesthesia machine must monitor in order to be in federal compliance

Back 30

1) Continuous breathing system pressure
2) Exhaled tidal volume
3) Ventilatory CO2 concentration
4) Anesthetic vapor concentration
5) Inspired O2 concentration
6) Arterial oxygen concentration
7) Oxygen supply pressure
8) Arterial blood pressure
9) Continuous EKG

Front 31

High pressure system check

Back 31

2) Check oxygen cylinder supply
a) open O2 cylinder and verify at least half full (about 1000psi),
close cylinder
3) Check central pipeline supplies
a) check that hoses are connected and pipeline gauges read about 50 psi

Front 32

Low pressure system check

Back 32

Check initial status of low pressure system
a) Close flow control valves and turn vaporizers off
b) Check fill level and tighten vaporizers’ filler caps

Front 33

Perform leak check of machine low pressure system

Back 33

a) Verify that the machine master switch and flow control valves are off
b) Attach “suction bulb” to common (fresh) gas outlet
c) Squeeze bulb repeatedly until fully collapsed
d) Verify bulb stays fully collapsed for at >10 seconds
e) Open 1 vaporizer at a time and repeat c and d above
f) Remove suction bulb, and reconnect fresh gas hose

Front 34

Test flowmeters

Back 34

a) Adjust flow of all gases through their full range, checking for smooth operation of floats and undamaged flowtubes
b) Attempt to create a hypoxic O2/NO2 mixture and verify correct changes in flow and/or alarm

Front 35

Scavenging system check

Adjust and check scavenging system

Back 35

a) Ensure proper connections between the scavenging system and both APL (pop-off) valve and ventilator relief valve
b) Adjust waste gas vacuum (if possible)
c) Fully open APL valve and occlude Y-piece
d) With minimum O2 flow, allow scavenger reservoir bag to collapse completely and verify that absorber pressure gauge reads about zero
e) With the O2 flush activated, allow the scavenger reservoir bag to distend fully, and then verify that absorber gauge reads <10cm H2O

Front 36

Breathing system check

Back 36

9) Calibrate O2 monitor
a) Ensure monitor reads 21% in room air
b) Verify low O2 alarm is enabled and functioning
c) Reinstall sensor in circuit and flush breathing system with O2
d) Verify that monitor now reads greater than 90%
10) Check initial status of breathing system
a) Set selector switch to “Bag” mode
b) Check that breathing circuit is complete, undamaged and unobstructed
c) Verify that CO2 absorbent is adequate
d) Install breathing circuit accessory equipment (ie. Humidifier, PEEP valve) to be used during the case

11) Perform leak check of breathing system
a) Set all gas flows to zero (or minimum)
b) Close APL (pop-off) valve and occlude Y-piece
c) Pressurize breathing system to about 30 cm H2O with O2 flush
d) Ensure that pressure remains fixed for at least 10 seconds
e) Open APL (pop-off) valve and ensure that pressure decreases

Front 37

Manual and automatic ventilation systems check

Back 37

Test ventilation systems and unidirectional valves
a) Place a second breathing bag on Y-piece
b) Set appropriate ventilator parameters for next patient
c) Switch to automatic ventilation (Ventilator mode)
d) Turn ventilator ON and fill bellows & breathing bag with O2 flush
e) Set O2 flow to minimum, other gas flows to zero
f) Verify that during inspiration bellows delivers appropriate tidal volume and that during expiration bellows fill completely
g) Set fresh gas flow to about 5L/min
h) Verify that the ventilator bellows and simulated lungs fill and empty appropriately without sustained pressure at end expiration
i) Check for proper action of unidirectional valves
j) Exercise breathing circuit accessories to ensure proper function
k)Turn ventilator OFF and switch to manual ventilation (Bag/APL) mode
l) Ventilate manually and assure inflation and deflation of artificial lungs and appropriate feel of system resistance and compliance
m) Remove second breathing bag from Y-piece

Front 38

Monitors check

Back 38

13) Check, calibrate and/or set alarm limits of all monitors
-Capnometer -Oxygen analyzer
-Pressure monitor with -Respiratory volume
high and low airway alarms monitor (spirometer)

Front 39

Final position check

Back 39

Final position
14) Check final status of machine
a) Vaporizers off
b) APL valve
c) Selector switch to “Bag”
d) All flowmeters to zero
e) Patient suction level adequate
f) Breathing system ready to use

Front 40

CO2 Absorbant

Back 40

Function: makes rebreathing possible, thus conserving gases and volatile agents, decreasing OR pollution, and avoiding hazards of CO2 re-breathing
Soda lime-Activator: NaOH or KOH. Silica and kieselguhr added as hardeners
Indicators for Sodasorb are colorless when fresh, and purple when exhausted because of pH changes in the granules
Gas flows downward

Front 41

CO2 Absorbant...more

Back 41

1) When soda lime is exhausted, the granules do not crumble
2) 1500cc canister holds a tidal volume of 750cc
3) Mesh size is 4x8, granules will fall through a screen with 4 wires/1 inch, but not through a screen with 8 wires/1 inch
4) A total obstruction of the circle system occurs if the clear plastic shipping wrapper is not removed from the CO2 canister before use

Front 42

To change canisters:

Back 42

1) Wear gloves
2) Loosen clamp
3) Remove and discard top canister
4) Promote the bottom canister to the top and put the fresh canister on the bottom
5) Check for circuit leaks
6) Always remove wrap before inserting canister
7) Don’t change mid-case; convert to semi-open circuit by increasing FGF to >5L/min

Front 43

Expired gas monitoring

Back 43

The most common type of monitor is sidestream. In this case a connector is placed in the circuit which is connedted to a small bore tubing (gas sampling line) that is then connected to the gas inlet of the monitor. A sample of gas from the breathing circuit is continuously collected by the monitor and measured.

Front 44

Compressed Gas Cylinders

Back 44

Steel tanks 3/8 inch thick, some are chrome alloy
Pressure tested to 5/3 their serve pressure
Subject to a test by interior hydrostatic pressure at least once/5 years

Front 45

Compressed gas cylinders Standards

Back 45

1) Interstate Commerce Commission: gas cylinder construction
2) Federal Food, Drug, and Cosmetic Act: regulates the medical gases contained in cylinders
3) United States pharmacopeia: regulates potency and purity
4) Department of Transportation: design, construction, testing, marking, labeling, filling, storage, handling, maintenance, and transportation
5) Compressed Gas Association: standards of safe practice. Has no legal force, but compliance is basis for accreditation by JCAHO
6) National Fire Prevention Associaion: same as CGA, recommendations for the location, construction, and installation of bulk oxygen systems
7) American National Standards Institute: sets down basic performance and safety requirements for components of anesthesia machines, endotracheal tubes, connections, pressure and vacuum, and gas pressure regulators
8) National Institute for Occupational Safety and Health Act: standards to protect the health and safety of workers
9) Food and Drug Administration: makes standards for medical devices and gases
10) American Society for Testing Materials: assess technology and revise standards
11) Joint Commission on Accreditation of Healthcare Organizations: voluntary accrediting agency
12) Pharmacopoeia of the US: develops purity spec’s for gases
13) National Formulary: developed purity spec’s for gases

Front 46

Compressed gas cylinders
Labeling and Marking

Back 46

A) All cylinders must be marked according to ICC regulations. The lettering must be _” high
B) 7 markings must be on the cylinder
1) Regulatory body (DOT), type/material of cylinder
2) Serial number
3) Purchaser, user, manufacturer
4) Manufacturer’s identifying symbol
5) Manufacturer’s manual
6) Retest date, re-tester, ID symbol, 110% filling, 10 year test
interval
7) Neck ring owners identification

Front 47

Critical temperature:

Back 47

the temperature at and above which vapor of the substance cannot be liquefied, no matter how much pressure is applied.

Front 48

Critical pressure:

Back 48

the pressure required to liquefy a gas at its critical temperature

Front 49

nitrous-blue

PSI
capacity

Back 49

745
1590l

Front 50

o2-green

psi
capacity

Back 50

1900 (full)

660l

Front 51

air-yellow

psi
capacity

Back 51

1900 (full)
625l

Front 52

Withdrawing cylinder contents:

Back 52

1) The cylinder should be opened slightly for a moment to clear the outlet of possible dust. This called cracking the cylinder.
2) The adiabatic heat of compression can generate heat and cause ignition. The compression of cylinder content into a smaller space generates the heat that may cause combustion.
3) Each valve stem on the cylinder has a safety device which under hazardous conditions of excessive heat or fire will cause the cylinder to become exhausted. This safety device is a simple plug of soft metal alloy called Wood’s Metal; it is composted of bismuth, lead, tin, and cadmium. This plug will melt at 200 degrees F.

Front 53

Oxygen:

Back 53

a) At room temperature, a full O2 cylinder is at 136 atm. Of
pressure or 2000 lb/in2 and contains 625 L of gas.
b) Oxygen behaves as an ideal gas: pV=m/MRT, where
V=volume, m=mass, M=molecular weight, R=universal
gas constant
c) for any isothermal process (T is constant) the product pV
is constant (boyle’s law)
d) for an isobaric process (p is constant) the ratio V/T is constant (Charles’ Law)

Front 54

Nitrous Oxide:

Back 54

Because the density of N2O vapor at 51 atm and 20 degrees C is less than _ the density of liquid N2O, the tank is actually less than _ full (or <400L) just before the tank pressure begins to fall

Front 55

breathing circuit with no reservoir

Back 55

open (open drop)

Front 56

circle circuit with APL closed

Back 56

closed

Front 57

circle circuit with low FGf's

Back 57

semi-closed

Front 58

2 circuits with no rebreathing

Back 58

open
semi-open

high FGF's
non-rebreather

Front 59

Closed Circuits

advantages/disadvantages

Back 59

Advantages:
1) Cost containment
2) Heat & moisture containment
Disadvantages:
1) Slow changes in amount of anesthetic delivered
2) Significant error possible since agent is closed to system over time.

Front 60

Mapleson Systems

Back 60

No valves, no CO2 absorption, variable rebreathing
A: SV
B: SV, FGF .8-2 x mV
B: CV, FGF 2-2.5 x mV
C: SV, FGF 2 x mV
C: CV, FGF 2-2.5 x mV
D: SV, FGF 1.5-3 x mV,
volume of tubing &
reservoir bag must
exceed patients tidal
volume
E: SV, FGF 2 x mV, “T-piece”
F: SV, FGF 2 x mV, “Jackson-Rees”

Front 61

NonRebreathing Circuits

Back 61

Mapleson D circuit is commonly used today
Mapleson D-modified “Bain system”







Mapleson F “Jackson-Rees modification of Ayre’s T-piece”
Coaxial “King system” has a single inspiratory limb inside the expiratory limb

Front 62

Mapleson F “Jackson-Rees modification of Ayre’s T-piece”

advantages/diosadvantages

Back 62

Advantages:
1) No valves to open, minimizes the work of breathing
2) Minimizes dead space.
The net result is a more rapid induction of anesthesia, but there is a greater risk of anesthetic overdose
Disadvantages:
1) Increased heat loss from the patient
2) Decreased humidity of gases
3) Need to deliver a fresh gas inflow more than twice the patient’s minute ventilation wasting large volumes of anesthetics.
All three disadvantages are a result of the
high flow rates in the nonrebreathing circuit

Front 63

Scavenging

Back 63

Receives gas from the machine (APL) and ventilator
Positive pressure relief valve will allow gas to escape from the system to the OR if pressure builds up in system
Wall evacuation system requires the needle valve to be properly adjusted. If excess flow is present then the negative pressure relief valve opens and waste gas enters the OR
Adjusting the needle valve alters the flow of waste gases into the vacuum source. Adjusting the needle valve does not regulate vacuum or suction

Front 64

Vaporizers

Back 64

Physics: All anesthetic vaporizers are designed to convert liquid anesthetic into vapor in a controlled fashion
Vapor: Gaseous phase of a substance that is liquid at room temperature and atmospheric pressure
Interlock System: Prevents more than one vaporizer from being turned on at a time. Also ensures vaporizers are locked in so leaks are decreased and vapor output is minimal when the vaporizer is off

Front 65

Vapor Pressure:

Back 65

Pressure exerted by the gaseous phase of a liquid substance. Molecules strike the container walls exerting pressure against the container

Front 66

Saturated Vapor Pressure:

Back 66

Maximum possible pressure at a given temperature. Equilibrium is established where the number of halothane molecules leaving the liquid phase equals the number re-entering the liquid phase from the gas phase.

Front 67

Physics:

Back 67

1) Increased T = Increased VP
2) Increased liq. T = eventually VP = atmospheric pressure
3) Pressure, this occurs at the boiling point of the liquid
4) Reducing the atm. P = reduces the boiling point
5) T dependent change in anesthetic VP is why anesthetic vaporizers need temperature compensation.
6) Temperature compensation allows a constant concentration output as the liquid anesthetic changes temperature during use of a vaporizer. As liquid anesthetic is vaporized, energy is removed from the liquid and the vaporizer, and the liquid anesthetic temperature will decline.

Front 68

Specific Heat:

Back 68

Amount of energy (in calories) required to increase 1 gram of substance 1 degree C. Therefore, substances with a low specific heat are easy to heat up, and those with a high specific heat will require more energy to heat.

Front 69

Thermal conductivity:

Back 69

Measure of the speed with which heat energy can flow through material. The greater the thermal conductivity, the better the material conducts heat. This allows for better flow of heat from the environment to the vaporizer and then to the liquid anesthetic.

Front 70

Calculating vaporizer flow output:

Back 70

Halothane VP=243, want 1% concentration @ 5L/min @760 mmHg (torr). 760 is sea level.
243/760 = .32, thus, 1/3 of the vaporizer output is saturated halothane vapor.

Front 71

Most modern vaporizers:

Back 71

Variable bypass, concentration calibrated, flow over, thermocompensation, agent specific, plenum type vaporizers. Exceptions are Siemens and Desflurane vaporizers.

Front 72

Malfunctioning vapoprizers:

Back 72

Incorrect filling, pumping/pressurizing, tipping, internal failure.

Front 73

Desflurane vaporizer:

Back 73

Boils at 23.5 degrees C., heated electrically to keep it in the vapor state (2 atm) which drives the agent towards the fresh gas flow. In contrast to other vaporizers, no fresh gas flow goes through the desflurane sump. Vaporizer will shut off if power goes out. In TEC 6 vaporizer, Des is heated to 39 degrees C.

Front 74

Problems & Hazards-vaporizers

Back 74

Administration of incorrect agent
Tipping
Overfilling with agent
Simultaneous inhaled agent administration
Leaks
Electronic Failures

Front 75

Problems & Hazards

Back 75

1) Hypoxia:
Incorrect gas supplied from cylinder
Hypoventilation or low flows
Insufficient gas in the system
Kinked/compromised tube
2) Hypercapnia:
Hypoventilation, low flows
Inadvertent administration of carbon dioxide
Rebreathing without CO2 removal
Unidirectional valve problems
3) Breathing circuit: disconnected, occlusion, high flow
4) Bellows: leaks from improper seating or holes in bellows

Front 76

5 tasks of O2 in the SPDD model

Back 76

low pressure alarm
ventilator driving gas
oxygen flush
flowmeter
failsafe for n20, air

Front 77

The ______ is the ultimate destination of gases.

Back 77

scavenging system

Front 78

hospital pipeline pressure

Back 78

50 psi

Front 79

low pressure componenents [4]

(distal to flowmetere needle valve)

Back 79

thorpe tubes
vaporizers
check valves (if present)
common gas outleet

Front 80

intermediate pressure components (exposed to pipeline pressure)[6]

Back 80

pipeline inlets, check valves, guages
ventilator power inlet
oxygen pressure failure devices
flowmenter valve
oxtgen second stage regulator (if present)
fluch valve

Front 81

high pressure components
(exposed to cylynder pressure)(4)

Back 81

hanger yoke
yoke block with check valves
cylinder pressure regulators
cylynder pressure guage

Front 82

______ are a comm on source of leaks

Back 82

o-rings at pipeline

Front 83

working pressure of machine
pipeline pressure
tank pressure

Back 83

50psi
50 psi
45 psi (after regulator)

Front 84

at the pipeline a __, __ and __ are present

Back 84

filter
check valve
pressure guage

Front 85

required components

backup battery life

Back 85

30 minutes

Front 86

required components

high priority alarm

must sound if [3]

Back 86

-may not be silences for more than 2 minutes

1-if user adjustable limits are exceeded
2-if continuing high pressure is sensed
3-for negative pressure

Front 87

required components

disconnect alarms may be besed on [3]

Back 87

low pressure
exhaled volume
CO2

Front 88

required components

automatically enabled alarms [4]

Back 88

-breathing circuit pressure
-oxygen concentration
-exhaled volume
-carbon dioxide monitor

Front 89

required components

monitors {8}

Back 89

-exhaled volume
-inspired oxygen (30sec-if <18% FI02)
-oxygen supply failure alarm
-hypoxic guard system
-anesthetic vapor concentration
-pulse oximetry
-NIBP
-EKG

Front 90

requirements

pressure in breathing system is limited to ______

Back 90

125cm H20

Front 91

requirements

the cylindeer

Back 91

at least one oxygen cylinder
pin indexed
pressure guage

the machine must use the pipeline supply as long as the pressure is greaeter than 50 psi

Front 92

requirements

flowmeters [7]

Back 92

-single for each gas
-flow control next to flow indicator
-fluted knob (different for 02)
-valve stops
-02 flow is on the right
-02 enters manifold downstream of the other gasses
-an auxillary flowmeter is strongly recommended

Front 93

requirements


02 flush [3]

Back 93

-an 02 flush must be present
-capable of 35-75 lpm
-does not go through any vaporizers

Front 94

requirements

vaporizers [6]

Back 94

-concentration calibrated
-an interlock must be present
-liquid level indicator
-designed to prevent overfilling
-should used keyed devices
-no discharge of liquid even at max FGF

Front 95

requirements

common gas outlet [4]

Back 95

-only one CGO
-22mm outer diameter
-15mm inner diameter
-designed to prevent accidental disconnection

Front 96

requirements

pipeline gas supply [5]

Back 96

-pipeline pressure guage
-inlets for at least 02 and N20
-DISS protected
-in-line filter
-check valve

Front 97

requirements

a ______ data interface must be provided

Back 97

digital

Front 98

In the event of a suspected cross-over, what do you do? [3]

Back 98

-open emergency 02 cylinder supply,
-disconnect pipeline supply
-consider low FGF, manual ventilation

Front 99

the 02 tank has to be a minimum of ____ psi.

Back 99

1000 psi

Front 100

cylinders use the ______ pin index system

Back 100

PISS

Front 101

hanger yoke 3 functions

Back 101

-orients cylinders
-provides a gastight seal
-endures unidirectional flow

also has a mandatory filter and check valve.

Front 102

transfilling is a haxard because...

Back 102

cylinder filling creates HEAT

Front 103

What is the rationale for keeping cylinders closed during normal pipeline supply operation?

Back 103

there is no alarm when switching to the cylinder, there would be no alarm if the pipeline supply fails and the only alarm would be when the emergency supply is empty.

Front 104

______ the plastic cover on the port when installing.

Back 104

remove!

Front 105

always use a ______ when removing a cylinder from the hanger yoke.

Back 105

yoke plug

Front 106

When installing a cylinder. [7]

Back 106

-check labels
-crack vavle
-check PISS pins
-check for one washer only
-place in hanger yoke
-listen for leak
-check for proper pressure

Front 107

amount of gas remaining equation...

Back 107

capacity (l) divided by service pressure (psi) = remaining contents 9l0 divided by guage pressure (psi)

Front 108

the use of a mechanical ventilator uses approximately _____ of driving gas each minute.

Back 108

a minute volume

Front 109

N20 frost starts at

Back 109

4 lpm

Front 110

N20 is flammable?

Back 110

non-flammable, but supports combustion

Front 111

Drager Fabius GS

Back 111

-piston driven ventilator
-thermal anemometry (hot wire) flow sensor
-can do PCV
-variable bypass vaporizers (no tool needed)
-cicuit volume 2.8l of which 1.5l is absorbent volume)
-only loosse granules
-45 minute battery

Front 112

Drager Narkomed 6000/6400

Back 112

-piston driven ventilator
-ultrasonic flow ssensor
-can do PCV/SIMV
-variable bypass vaporizers (no tool needed)
-circuit vol (1.5l absorb)
-only loose granules

Front 113

Datex-Ohmeda Aestiva

Back 113

-gas driven bellows
-PCV
-high volume circuit (5.5)
-30 minute battery

Front 114

Datex-Ohmeda S/5 ADU

Back 114

-gas driven bellows
-variable bypass vaporizers (no tool needed)
-PCV/SIMV
-very low volume circuit (only 750ml absorb)

Front 115

most fragile part of machine?

Back 115

flowtubes

turn off before connecting gas and at end of day.

Front 116

excessive use of the flush valve can result in..

Back 116

barotrauma
dilution of inhalatinoal agents leading to a decreased depth of anesthesia

Front 117

failsafe mech's do what

Back 117

prevent the delivery of a hypoxic gas mixture in the event of 02 supply failure

Front 118

low pressure alarms

Back 118

28-37mmhg

Front 119

______ ventilators can be used outside of the OR for prolonged periods because..

Back 119

they use electric motors to comp0ress the bellows, therefore not exhausting the FGF supply

Front 120

all current machines incorporate hypoxic guard system that limit to final misture to at least ______ % 02

Back 120

25% +/- 4%

Front 121

a vapor is compsed of molecules that are liquid at __ and __

Back 121

room temp and q atm.

Front 122

as evaporation proceeds, the remaining liquid and it's container cool because..

this is called the...

Back 122

heat enregy is carried from the liquid with the energetic, mobile evaporating molecules (joule/thompson effect)

the latent heat of evaporization

Front 123

______ limits the rate of evaporization

Back 123

cooling

Front 124

vaoprizers need a _____ and _____ to stabilize anesthetic temperature

Back 124

high thermal conductivity

high thermal capacity

Front 125

the rate of evaporization depends on [4]

Back 125

temperature
vapor pressure of the liquid
partial pressure of the vapor above the liquid

Front 126

the splitting ration is the..

Back 126

gas entering the chamber divided by the FGF.

automatically determined by variable bypass vaporizeers

Front 127

the flow entering the chamber is called the [2]

Back 127

chamber flow
carrier gas

Front 128

full saturation of the carrie gas is by means of ___ and _____

Back 128

wicks
baffles

Front 129

sa the vaporizer cools more/less gas is directed into the chamber?

Back 129

more

Front 130

variable bypass vaporizers are in/out of the circut?

Back 130

out

Front 131

measured flow vaporizers..

Back 131

can be used with any agent
operator deterimes amount of gas bubbled through the liquid by a formula
called maula temperature compensation

Front 132

which vaporizer is heated for des?

Back 132

datex-ohmeda Tec 6

heated dual circuit 39C, 1500mm

uses a vapor-circuit that is mised with FGF circuit

Front 133

The modern vaporizors output may be influenced by [3]

Back 133

extremes of FGF
extremes of temp
backpressure from the vent/circuit

Front 134

what limits the 'pumping effect'?

Back 134

a unidirection valve at the chamber inlet or distal to the vaporizer

Front 135

What prevents the operator from delivering more that one agent at a time?

Back 135

interlock system

Front 136

variable-bypass vaporizers must be on/off while filling?

Back 136

off

Front 137

preop check for VB vaporizers? [3]

Back 137

are they full?
are they on off?
is the interlock funtioning?

Front 138

preop check for Tec-6(des)?

Back 138

check alarm-low battery
turn on at 1%, pull plug, alarm in 15 sec (no output alarm)
trun off reconnect power, mute for 4 sec to test alarms and display

Front 139

The purpose of the anesthesia breathing circuit is...

Back 139

delivery of 02 and elimination of C02

Front 140

advantages of a rebreathing circuit are...[3]

Back 140

cost reductions
warmth and humidity
decreased exposure to gases

Front 141

Va=VE - ______

Back 141

dead space

Front 142

the most common circuit is the ___

the Bian modification is...

how to test?

Back 142

mapleson D

the FGF is inside the inspiratory corrrugated tubing.

must use the Pethick test

Front 143

The minimm weight of a child in whom a pediatric circuit would be suitable is __ to __

Back 143

10-20kg

Front 144

The FGF required to prevent rebreathing is_____

Back 144

2 to 3 times the VE

Front 145

breating circuit system most commonly used is-----

Back 145

circle system

Front 146

gas enters the circle system from the _____ and exits at the ____

Back 146

CGO

APL

Front 147

only 2 reasons for an increase in inspired C02

Back 147

exhausted absorbent granules
faulty unidirectional valves

Front 148

The time constant equals ____ divided by ____ and measures how quickly a breathing system reaches equilibruim with changes in inlflow.

Back 148

capacity/flow

Front 149

The correct response to increased C02 resultinmg from exhausted absorbant is...

Back 149

increase GFG (NOT Ve)

Front 150

The absorption of 1 mol of C02 produces ____ Kcal of heat energy

Back 150

13,000

Front 151

at a critical ph of _____ ethyl viloet changes to bluish purple

Back 151

10.3

Front 152

main constituent of sada lime?

ideal water %?

size?

Back 152

calcium hydroxide

14-19%

4-8 mesh

Front 153

soda lime degredation...

most/least

Back 153

most-Sevo (compound A)

lest-Des

Front 154

Sevo low FGF #'s?

Back 154

total FGF's of less tha 1 LPM for more than 2 MAC hours

Front 155

Carbon monoxide produciton,

most/least

Back 155

most-des
least-iso

gretest with baralyme

Front 156

____ is the new absorbent

Back 156

Amsorb

Front 157

absorbent/canister resistance?

Back 157

less than 1.5 cm at a flow of 100LPM

Front 158

after a pressure check, always release the pressure throught the ____

Back 158

APL valve

Front 159

Do/don't replace canisters in the middle of a case?

Back 159

NO

don't

Front 160

each 100gm of granules can absorb as much as ______ of C02

Back 160

15 liters

we produce about 12-18 liters per hour

Front 161

fires may occur if sevo is used with..

Back 161

a dessicated absorbent

Front 162

There is ________ PEEP in the breathing circuit when standing bellows mechanical ventilation is used

Back 162

2-3cm

Front 163

______ bellow are the safest.

Back 163

ascending

Front 164

typical CMV settings

Back 164

10ml/kg VT
rr 6-12
0 peep to start

Front 165

PCV indications

Back 165

low complicance
laparoscpopy
infants
pregnacy
ARDS

Front 166

no inherent PEEP with _____ ventilators

Back 166

piston driven

Front 167

______ helps to ensure that the set and delivered tidal volumes are equal.

Back 167

FGF decoupling

Front 168

____ is the most common preventable equipment related cause of mishaps

Back 168

failure to ventilate caused by disconnection

Front 169

the m ost important monitor for disconnection is _______ and ______

Back 169

continuous aucultation

direct visualizatin of chest wall movement

Front 170

how much gas is scavenged each minute?

Back 170

an amount equal to FGF

Front 171

The most important componetn of the scaveging system is the...

Back 171

interface, because it proects the patient adn breathing circuit from excessive buildup of positive pressure and from exposure to suction.

Front 172

______ is mandatory for all closed scavenging interfaces (older machines)

with an open system there are no ______ to impede flow into or out of the reservoir

_____ is critical to scavenging system fucntion

Back 172

relief of pressure

no valves in open

an appropriate suction device

Front 173

The open scavenging system interface should/should not hiss if functining properly

Back 173

should HISS

Front 174

leaks in the low pressure system could lead to _____ and ______

Back 174

hypoxic breathing mixtures

awareness under anesthesia

Front 175

what do you do?

decreased FI02?

Back 175

call for help
open the cylinder and disconnect the pipeline
if that doesn't increase the FI02, ambubag with room air

Front 176

what do you do?

Pethick test for Bain circuit.

Back 176

occlude elbow
close APL
fill circuit with flush valve
release occlusion at elbow and flush. a venturi effect flattens the reservoir bag if the inner tube is patent

Front 177

what do you do?

sustained high breathing circuit pressure?

Back 177

1-try manual ventilatin in BAG mode (that works, you have a faultyventilator releif valve-new vent)
2-scavenger could be obstructed or its relief valves failed
3-disconnect the scavenger gas collectin tubing from the back of the APL
4-if still nogo, then ventilate by ambu bag

Front 178

with AIDS..

Back 178

avoid using mechanincal ventilators
use bacterial and virela filters on each limb
use a dispoisable soda lime assembly
change soda lime after each

Front 179

Wash in time constants

Back 179

1 time constant=capacity/flow

1-63%
2-86%
3-95%

Front 180

density equation

Back 180

density = weight x volume

Front 181

ideal gas law

Back 181

PV = nRT

p=pressure
V=volume
n=number of gas molecules
r=contant for all gases
t=absolute tem (in kelvin)

kelvin = C+273

Front 182

Boyle's law

Back 182

expresses the compressability of gases

P1V1=P2V2

constant temp

Front 183

Charles's Law

Back 183

if pressure is held constant, the volume of expansion is proportional to the absolute temperature
V

V1/V2=T1/T2

constant pressure

Front 184

Gay-Lussac's law

Back 184

When volume is held constant, gas pressure varies directly with absolute temperature

P1/P2=T1/T2

volume is constant