Equipment Flashcards
1
Q
Check valve in pipeline inlet assembly is a floating valve and seats according to pressure. What is the function of this valve?
A
Prevents oxygen cylinder gas from escaping the anesthesia machine
2
Q
Power outlet valve for ventilator
A
DISS fitting
Ball and spring type valve
YOU supply the energy
3
Q
Hanger yoke valve
A
Pins : Air - 1,5/ O2 - 2,5/ N2O - 3,5
Free floating valve
Prevents a full cylinder from emptying into an empty cylinder or wall oxygen from entering a cylinder
4
Q
What is the name of the gauge that shows oxygen tank pressure?
A
Bourdon
5
Q
You have a dual hanger yoke with 2 oxygen E cylinders. Both cylinders are turned on; which one will supply the gas machine?
A
The E cylinder with the highest pressure
6
Q
Pressure Regulators
A
Diaphragm valves
ONLY role = REDUCE PRESSURE
7
Q
First Stage Regulators
A
High (cylinder) pressure decreased to intermediate pressure (40-50 psig)
*Diaphragm valve
8
Q
Second Stage Regulators
A
Intermediate pressure decreased to low pressure (16 psig)
Receives oxygen from first stage regulator OR wall pressure oxygen
*Diaphragm valve
9
Q
Oxygen Flush Valve
A
Flow rate: 35-75 L/min
Pressurized: 40-50 psig (intermediate pressure)
Ball and spring valve
YOU supply the energy
10
Q
What are the 2 negatives of the oxygen flush valve?
A
- May cause barotrauma
2. Dilutes anesthetic gas
11
Q
Pressure Sensor Shut-Off Valve
Oxygen Failure Pressure Device
A
Senses oxygen pressure at intermediate pressure
Shuts off nitrous oxide if oxygen PRESSURE falls (< 25 psi)
Ball and spring valve
12
Q
Oxygen Flow Meter
Flow Control Valve
A
Receives low pressure (16 psig)
Thorpe tube is gas specific and tapered
13
Q
Check Valve Located b/t the Vaporizer Outlet and the Machine CGO
*Ohmeda machine only!
A
Prevents reversal of flow to vaporizer (back pressure)
Free-floating type valve
14
Q
What happens if the inspiratory valve sticks open?
A
Expiratory volume will exhaust through the inspiratory limb
ETCO2 waveform will become elevated
15
Q
What happens if the expiratory valve sticks open?
A
Inspired volume will not enter the ETT
It will exhaust through the expiratory limb
16
Q
Inspiration and Expiration Check Valves
A
Flutter valves
Unidirectional flow
17
Q
APL valve
A
Pop off
Attached to the exhalation check valve
Adjusts the limit of pressure in that patient circuit and rebreathing bag
18
Q
Waste Gas Scavenging System
A
Adjusting the needle valve alters the FLOW of waste gases into the vacuum
19
Q
What will happen when the vaporizer is tipped?
A
Liquid vapor will get into the vaporizer chamber
Carrier flow will carry MORE agent
Do NOT use, needs to be re-calibrated
20
Q
High Pressure (cylinder)
A
Cylinder pressure
Bourdon gauge
Check valves in the hanger yoke
Index pins on the hanger yoke
21
Q
Intermediate Pressure (40-50 psi)
A
Flush valve Second stage regulator Oxygen pressure "failsafe" shut-off valve Pressure gauges from pipeline DISS Flow control valve of manifold Flow meter valves Ventilator power inlet
22
Q
Low Pressure (16 psi)
A
Vaporizer
CGO
Manifold/Flow meters
Check valves
23
Q
Free Floating Valve
A
DISS
Dual hanger yoke systems
Prevent gases from leaking out of the system
24
Q
Ball and Spring Valve
A
Oxygen flush valve
Oxygen pressure sensor valve
25
Diaphragm valve
First and second stage regulators
| Reduce pressure
26
The path...
Oxygen cylinder - open cylinder valve - hanger yoke system - free floating valve - first stage regulator - NOW 4 options
27
What are the 4 options following the first stage regulator?
1. Oxygen pressure sensor valve
2. Flush valve
3. DISS
4. Second stage regulator - flow meters - vaporizer - CGO - soda lime - inspiratory valve - inspiratory limb - ETT
28
What type of anesthesia machines should be tested with a negative-pressure leak test?
Machines with check valves
Suction bulb is attached to the CGO - squeezed repeatedly until the bulb is fully collapsed - leak-free if the bulb remains collapsed for a least 10 sec
29
Your next patient has MH. What 3 steps will you take?
1. Flush gas machine for 10 min
2. Replace the breathing circuit and the CO2 canister
3. Remove vaporizers
30
What is the purpose of the interlock system?
Prevents more than one vaporizer from being turned on at a time
31
What are your actions when the oxygen low-pressure alarm sounds?
D/c pipeline
Open E cylinder
Use low flow FGF
32
The vacuum control valve should be adjusted to allow the evacuation of what volume of waste gas per min?
10-15 L/min
33
What is the purpose of the proportioning system?
Prevent hypoxic mixture
N2O and O2 are mechanically/pneumatically linked
Min O2 concentration at CGO is b/t 23-25%
Max N2O-O2 flow ratio of 3:1
34
Who controls such processes as the filling and manufacturing of gas cylinders?
The US Department of Transportation
35
What is the working pressure of the hospital pipeline system?
50 psig
36
What is the most common contaminant of medical gas lines?
Water
37
Which 2 gases are in liquid form in pressurized cylinders?
1. N2O
| 2. CO2
38
When should you change the O2 cylinder?
When < 1000 psi
| Half full
39
The nitrous oxide tank reads 700 psi. What is the significance of this?
N2O pressure below 745 psi indications that the cylinder has NO liquid and is < than 1/4 full (400 L)
Change!
*Does NOT follow Boyle's Law
40
Calibration of flowmeters is based upon what physical property of gases: density or viscostiy?
Low flows - viscosity - laminar
| High flows - density - turbulent
41
All compressed gas cylinders are constructed according to...
Interstate Commerce Commission specifications
ICC3S
Must have 7 cylinder markings
42
Each cylinder must be subject to a test by interior hydrostatic pressure at least once every...
5 years
43
Explain the safety device on each valve stem on the cylinder.
Under hazardous conditions of excessive heat or fire the cylinder will become exhausted
This is a simple plug of soft metal alloy called Wood's metal
44
What does it mean when you crack the cylinder?
Open the cylinder slightly to clear the outlet of possible dust
45
Open System
| No Mask On Face
No dead space
No rebreathing or reservoir bag
No valves
Pediatric induction
46
Semi-Open
| Mask On Face
No rebreathing
Unidirectional valve
Reservoir bag
Room pollution
High FGF
Open drop technique
47
Semi-Closed
| Mask On Face
No room air inspired
CO2 absorber
Unidirectional valves
Reservoir bag
FGF can be < MV
Circle system
48
Closed
| Mask On Face
Rebreathing gases - pop off closed
CO2 absorber
Unidirectional valves
Flow 150-500 mL/min - physiological requirements
Flow 150-250 mL/min - under anesthesia
49
Specific Semi-Open Systems
Mapleson Systems - 5 Components
```
No rebreathing
Unidirectional valve
Reservoir bag
Room pollution
High FGF
```
1. Face mask
2. Spring-loaded pop-off valve
3. Reservoir tubing
4. Fresh gas inflow tubing
5. Reservoir bag
50
Mapleson A is best for what? Worst for what?
Best for spontaneously breathing patient
| Worst for controlled ventilation
51
What is the most commonly used breathing system today?
Bain Circuit
| Modification of the Mapleson D system
52
Which Mapleson systems are rarely used today?
A, B, C
53
Which Mapleson systems can you ventilate an apneic patient?
All Mapleson systems
54
Mapleson Systems
| Preventing rebreathing during spontaneous ventilation
A > DFE > CB
55
Mapleson Systems
| Preventing rebreathing during controlled ventilation
DFE > BC > A
56
Which Mapleson System has the fresh gas inlet and popoff valve at opposite ends?
A
57
Which Mapleson System has the fresh gas inlet at mask end, next to popoff valve?
B, C
58
Which Mapleson System has fresh gas inlet at mask end and popoff valve at other end --- also called the T-piece group?
D, E, F
59
American Society for Testing and Materials standards for reservoir bags require that with a bag distended to ___x its normal capacity, the pressure will not exceed ___cmH2O.
4x
| 50 cmH2O
60
What are the 5 components of the circle system?
1. Gas reservoir bag
2. 2 corrugated tubes
3. 2 unidirectional valves
4. CO2 absorbent
5. Overflow valve
61
What is the most common site for breathing circuit disconnection?
B/t breathing system and ETT
62
Where does the FGF enter the breathing circuit in the circle system?
Semi-closed system
| B/t the absorbers and the inspiratory valve
63
In a circle system, where is dead space located?
B/t Y piece and the patient
64
When does a semi-closed, or semi-open, system exist?
When high FGF are used with a circle system
65
Which breathing circuits, open or closed, have the slowest induction time?
Closed
66
What flow rate must be achieved when using an Ayre's T-piece to prevent rebreathing or air entrapment?
2-3x the patient's MV
67
Mapleson ___ is the Jackson-Reese modification of Mapleson ___.
F
| E
68
Where should the oxygen sensor be placed in a circle system?
Inspiratory limb
69
Don't use an LMA with the following...
Risk of aspiration - NPO violations, > 14 weeks pregnant, hiatal hernia
Delayed gastric emptying issues - obese, DM, opiate use
Trauma
Acute abdomen
Thoracic injury
Decreased pulmonary compliance - peak airway pressures > 20 cmH2O
70
What nerve could you damage with insertion of an LMA?
Hypoglossal nerve
71
What is the max use per LMA?
40x
72
Is a NG tube compatible with an LMA?
Yes
| Pass NG before LMA
73
Where does the LMA rest?
Against the upper esophageal sphincter
74
How can the head be turned when an LMA is in place?
Side to side
| Do NOT flex or extend the neck
75
The following nerve injuries will cause hoarseness of the voice...
Bilateral superior laryngeal nerve injury
Unilateral recurrent laryngeal nerve injury
Unilateral vagus nerve injury
76
What nerve injury will cause aphonia?
Chronic bilateral recurrent laryngeal nerve injury
| (Acute - stridor, respiratory distress
77
Avoid vocal cord paralysis by not inflating the LMA cuff too much! What are the maximum cuff volumes for each size?
```
1 (5 kg) - 4 mL
1.5 (5-10 kg) - 7 mL
2 (10-20 kg) - 10 mL
2.5 (20-30 kg) - 14 mL
3 (30-50 kg) - 20 mL
4 - 30 mL
5 - 40 mL
6 (> 100 kg) - 50 mL
```
78
Fasttrach LMA
Epiglottic elevating bar int he mask aperture
79
What is the aspiration risk with an LMA? Incidence of sore throat?
Aspiration 2 per 10,000
| Sore throat 10%
80
What type of lubricant should be used with LMAs?
Water-soluble
| NOT silicone-based, lidocaine-containing
81
With use of an LMA...
Airway pressures should be < than?
TV should not be > than?
Mask should be inflated to a pressure of ____ cmH2O.
20 cmH2O
8 mL/kg
60 cmH2O
82
What do the initials RAE stand for?
Ring - Adair - Elwyn tube
83
List 5 risk factors for difficult mask ventilation from greatest to least.
1. Beard
2. BMI > 26
3. Edentulous
4. Age > 55
5. History of snoring
84
What is the max ETT that can be passed through an intubating LMA?
8.0
85
What is the distance an ETT moves from flexion to extension?
3.8 cm (1.9 each direction)
86
During apnea, PaCO2 will rise by ___ mmHg during the first min, and _____ mmHg each minute thereafter.
6
| 3-4
87
Name 3 rigid, fiberoptic laryngoscopes.
1. Bullard
2. Wu
3. Upshur
88
What is Ludwig's angina? What is the most common cause?
Generalized septic cellulitis of the submandibular region
Cause: hemolytic strep
*Trach candidate
89
What do you need for transtracheal jet ventilation?
```
12-14-G needle
3 mL syringe
Self-inflating reservoir bag
ETT tube adapter
Oxygen supply
Driving pressure of at least 50 psi
```
90
What is the best way to assess mobility of the TMJ?
Ask the patient to open his/her mouth
| Simultaneously assess cervical spine mobility
91
What BIS level corresponds to flat-line EEG?
10-0
92
Pulse Ox
```
Beer-Lambert Law
Principles of oximetry and plethysmography
2 wavelengths
Red light - deoxyhgb - 660 nm
Infrared light - oxyhgb - 940 nm
Accurately detects SaO2 (predicts PaO2)
```
93
List 4 examples of low perfusion states that can cause pulse ox artifact.
1. Low CO
2. Anemia
3. Hypothermia
4. Increased SVR
94
List examples, unrelated to low perfusion, that interfere with an accurate pulse ox reading.
Carboxyhemoglobin - false HIGH
Methemoglobinemia - locked at 85%
Methylene blue dye
*NOT - fetal hgb or bilirubin
95
What 2 measurements assess blood oxygen?
1. PaO2
| 2. SaO2
96
Capnometry vs. Capnography
Capnometry: #s
Capnography: waveform
97
Abnormal Capnogram
Incompetent Expiratory Valve
Incompetent Inspiratory Valve
Exhausted Soda Lime
Capnogram does NOT return to baseline
*Incompetent Inspiratory Valve - inspiratory limb prolonged, "take-off" angle
98
Does the capnogram of a patient with MH return to baseline?
YES
| Very, very rapid increase in CO2
99
Abnormal Capnogram
ETCO2 is low
Alveolar plateau is angled
Rate is increased
Pulmonary Embolism
100
Which phase of the capnogram reflects a mixture of anatomic and alveolar dead-space?
Phase II
101
What phase of the capnogram is the alveolar plateau?
Phase III
102
What phase of the capnogram represents inspiration?
Phase IV
103
The slope of Phase III of the capnogram depends on...
V/Q status
| *Airway obstruction and PEEP cause an increased slope and a larger alpha angle
104
What are the normal degrees of the alpha and beta angles on the capnogram?
Alpha: 100-110 deg
Beta: 90 deg
105
What gases are measured by mass spectrometry?
CO2, O2, N2, inhaled agents
106
Can the mass spectrometer detect a V/Q mismatch?
NO
| Doesn't assess PaO2
107
CVP waveform
```
A: atrial contraction +
C: tricuspid valve elevation +
X: ventricular systole -
V: venous return to atrium +
Y: early ventricular filling -
```
108
Large A waves
Tricuspid stenosis
Pulmonic stenosis
Pulmonary HTN
Decreased RV compliance
*Absent in Afib
109
Large V waves
Tricuspid regurgitation
RV papillary muscle ischemia/RV failure
Constrictive pericarditis
Cardiac tamponade
110
The RVEDP is ___ the LVEDP in a healthy heart.
3/4
111
When the CVP line is inserted via the RIJ, the tip of the cath on x-ray will be seen at the level of what thoracic vertebrae?
Below the inferior border of the clavicles
Above the T4-T5 interspace
Above the level of the 3rd rib
112
What would cause the CVP > PCWP?
RV failure
Pulmonary HTN
PE
113
```
Pulmonary Artery Cath Distances
Insertion Sites
Subclavian
RIJ
LIJ
R AC
L AC
Fem
*RA to RV to PA
```
```
Subclavian - 15
RIJ - 20
LIJ - 25 - should NOT be used for PA?
R AC - 40
L AC - 45
Fem - 50
Those are to RA
To get to RV + 10
To get to PA + 25
```
114
Describe the RV tracing while placing a PA cath.
Pressure - 15-25/1-8
| No dicrotic notch
115
Describe the tracing once the PA cath reaches the PA.
Pressure - 15-25/8-15
| Dicrotic notch
116
RAP = CVP = RVEDP =
0-8 mmHg
117
RVA = PAS =
15-25 mmHg
118
PADP =
8-15 mmHg
119
PCWP
Normal: 6-12 mmHg
Measures "back pressure" from the pulmonary veins
Max wedge time is 15 sec
PCWP is NEVER higher than PADP
120
```
What will happen to CVP and PCWP with the following?
Hypovolemia
LV failure
RV failure
PE
Pulmonary HTN
Cardiac tamponade
```
Hypovolemia - low CVP and PCWP
LV failure - normal CVP and high PCWP
RV failure - high CVP and normal PCWP
PE - high CVP and normal PCWP
Pulmonary HTN - high CVP and normal PCWP
Cardiac tamponade - high CVP and PCWP
121
List 3 contraindications to use of a PA cath.
1. Complete LBBB
2. WPW
3. Ebstein's malformation
122
Is the area under a thermodilution curve directly related or inversely related to CO?
Inversely
| Smaller area - Higher CO
123
Why is it important to inject such a precise volume when measuring CO via thermodilution curve?
If you inject too small of volume - false high CO
| If you inject a large volume - false low CO
124
Insufficiency of what 2 valves may lead to a falsely high thermodilution CO reading?
Regurgitation of either the tricuspid or pulmonic valve
125
Any PA cath measurements are equivalent indirect indicators of _____ in the absence of mitral stenosis or pulmonary HTN.
Preload
126
Does PCWP under or overestimate LVEDP in the patient with mitral valve stenosis?
Overestimate
| *Mitral valve insufficiency is NOT a factor that can lead to a false estimate
127
Identify 3 situations where PCWP > LVEDP.
1. Mitral stenosis
2. Elevated alveolar pressure
3. Pulmonary venous obstruction
128
PCWP will underestimate LVEDP in patients with what valve issue?
Aortic regurgitation
129
If the BP cuff is too big, then the BP will be _____.
Lower
130
What sounds identify the onset of systole?
Karotkoff sounds
131
What 3 valuable CV parameter are obtained from an Aline?
1. LV volume
2. LV function
3. SVR
132
Where is the proper placement of the pressure transducer in a sitting position?
At the base of the ear
133
What does the dicrotic notch represent on the Aline tracing?
Closure of the aortic valve
134
Overdamping of the Aline results in what?
Underestimation of the SBP
Overestimation of the DBP
MAP remains constant
135
What nerve could you possibly damage when placing an aline in the brachial artery?
Median nerve
136
The width of BP cuff should be ___% of the arm's circumference.
40%
137
Is the BP reading erroneously high or low when the cuff is too narrow or wrapped loosely?
High
138
When using a tourniquet, where can most damage occur to a limb, proximal to, distal to, or under the cuff?
Under the cuff
139
The BIS reading is a derived # that correlates with the level of:
Hypnosis
140
Department of Transportation
Defines compressed gas standards
| Established design, construction, testing, marking, labeling, and transportation requirements for gas cylinders
141
Interstate Commerce Commission
Sets specifications for compressed gas cylinder construction
142
Federal Food, Drug, and Cosmetic Act
Regulates the medical gases contained in cylinders
143
US Pharmacopeia
Develops purity standards for medical gases
144
National Fire Prevention Association
Has recommendations for the construction and location of bulk oxygen containers
145
Compressed Gas Association
Set standards of safe practice
146
American National Standards Institute
Performance and safety requirements for components of anesthesia machine, ETT, connectors, vacuum, and gas pressure regulators
147
American Society for Testing Materials
Assess technology and revises standards
148
What vaporizer delivers isoflurane, enflurane, halothane, and sevoflurane?
Variable-bypass vaporizers
- Agent-specific
- Temp compensated
- Flow over
- Maintains constant partial pressure
149
Describe the vaporizer for desflurane.
Tec 6
Dual-gas blender
39 deg C
1500 mmHg
Maintains constant concentration of vapor output (must adjust in higher altitudes - increase concentration)
Why is it special? Vapor pressure is near atmospheric pressure, boils at sea level and it is only 1/5 as potent as other agents so a large volume must be delivered to the patient
150
In most instances, ___ psi is a sufficient inspiratory pressure.
25
151
Operation of the jet ventilator is based on what principle?
Venturi effect
| Bernoulli principle
152
What are the 5 final products when CO2 reacts with soda lime?
1. Calcium carbonate
2. Sodium hydroxide
3. Potassium hydroxide
4. Water
5. Heat
153
What are the 4 final products when CO2 reacts with Baralyme?
1. Calcium carbonate
2. Barium hydroxide
3. Water
4. Heat
154
Does the descending bellows descend during the inspiratory or expiratory phase?
Expiratory
155
Which bellows are safer when there is a disconnect...ascending or descending?
Ascending
| will not rise if disconnection occurs
156
What is another name for the bougie?
Eschmann introducer
157
What are the 3 characteristics of the high frequency jet ventilator? What does it require?
1. Small TV (< dead space)
2. High ventilation rate
3. Low airway pressures
Requires a high-pressure oxygen source (central wall outlets, tank regulators, flush valve) and a regulating valve
158
What is the most common complication to a patient being jet ventilated?
Tracheal mucosal damage and thickened secretions blocking the airways (inadequate humidification)
159
What site gives the most reliable approx of core body temp?
Lower 25% of the esophagus
Most accurate - PA cath
160
Where is the ideal placement of the esophageal stethoscope?
Lower 1/3 of the esophagus
161
Intraoperative Blood Salvage
Contamination with what is relatively common?
What coagulopathy is expected?
Bacteria, skin organisms
Dilutional coagulopathy - washing process removes all clotting factors and most plts
162
Will fail safe valve prevent delivery of hypoxic mixture?
NO
163
Most volatile agents produce about 200 mL of gas for each mL of liquid.
100 mL of Sevo, 3 L/min, 2%
3000 x 0.02 = 60 mL/min of Sevo
100 x 200 = 20,000 mL of gas
20,000/60 = 333 min
