FINAL REVIEW Flashcards
(151 cards)
1
Q
What are the characteristics of oxygen?
A
Non-flammable, oxidizing and supports combustion
Colorless, tasteless, transparent and odorless
2
Q
What are the advantages to storing O2 in liquid form vs gas?
A
Liquid has more storage capacity and is more convenient. Also its less hazardous and operates at a lower pressure. No regulator is needed
3
Q
What are the different Heliox mixtures and their dilution factors?
A
80/20 - 1.8
70/30 - 1.6
4
Q
What does the DOT stand for and what do they do?
A
Department of Transportation- they regulate manufacturing and filling and do hydrostatic testing every 5-10 years
5
Q
What does the CGA stand for and what do they do?
A
Compressed Gas Association- they regulate storage and safety and color codes
6
Q
What does the NFPA stand for and what do they do?
A
National Fire Prevention Agency- they regulate bulk O2 systems
7
Q
What are the DOT fabrication markings mean? (3A, 3AA, and 3M)
A
3A- Carbon steel
3AA- Steel alloy
3M- Aluminum
8
Q
How often are safety tests performed for medical gas cylinders?
A
Every 5-10 years
9
Q
What does EE- (followed by a number) stand for on a gas cylinder?
A
Elastic expansion
10
Q
What does * (next to a date) stand for on a gas cylinder?
A
This indicates DOT approval for 10 year testing
11
Q
What does + mean on a gas cylinder?
A
This means the cylinder can be filled 10% above service pressure
12
Q
What type of tanks CANNOT be overfilled?
A
Aluminum
13
Q
What is a frangible disk?
A
A safety feature on a gas cylinder that ruptures at 3000 psi
14
Q
What is a fusible plug and what type of tanks are they common on?
A
It is a safety feature on a gas cylinder that melts at 170 degrees C (on most small cylinders)
15
Q
What safety feature is on most large cylinders?
A
Spring loaded- opens and vents gas at set high pressures
16
Q
What does PISS stand for and what type of tanks?
A
Pin Index Safety System and it is for small cylinders
17
Q
What does ASSS stand for and what type of tanks?
A
American Standard Safety System and it is for larger cylinders (threaded)
18
Q
What does DISS stand for and what type of tanks?
A
Diameter Index Safety System and it is for low flow gas connectors like in the wall at hospitals (Quick Connect)
19
Q
What type of medical cylinder is green? Brown? Yellow?
A
Green- Oxygen
Brown- Helium
Yellow- Air
20
Q
How do you measure gas filled cylinders vs liquid cylinders?
A
Gas- a full tank is 2200 and it is directly proportional to its pressure (psi)
Liquid- weight
21
Q
What are the conversion factors for E, G and H tanks?
A
E- .28
G- 2.41
H- 3.14
22
Q
What are the 3 types of flow meters?
A
Flow restrictor
Bourdon gauge
Thorpe tube
23
Q
In what situation is the Bourdon Gauge a good option and why? What does the Bourdon gauge measure?
A
It is great for transport and can be used in any position (laying down). It measures pressure, not flow
24
Q
What happens when the Bourdon Gauge has back pressure?
A
The reading stays the same and yet the patient is getting less than what the gauge says.
25
What type of orifice and pressure does the Bourdon gauge and Thorpe tube use?
Bourdon gauge - fixed orifice and adjustable pressure reducing valve
Thorpe tube- flow variable orifice and constant pressure device (always 50 psi)
26
What are the 2 types of Thorpe tubes available and in what situation is it not ideal?
Uncompensated and compensated and it is not ideal for transport because it is only accurate in an upright position
27
What does increasing the size of the tube do to the gas flow?
Increases it
28
What is the difference between a compensated and uncompensated Thorpe tube?
Uncompensated shows flow lower than actually delivered to patient if there is a kink and compensated is not affected by back pressure and reads actual flow going to patient
29
How do we know if we are using a compensated Thorpe tube when we plug it into the wall?
The ball will jump up and fall back down
30
What is a regulator?
A pressure reducing valve and flow meter together (high pressure gas cylinders need them)
31
Why do we crack the tank before using?
The clear out dust and debris
The prevent damage to the regulator
32
What type of bulk system do most large facilities use?
Liquid bulk
33
What are zone valves used for and how do we turn them off?
They are used for maintenance and in case of fire. We can turn them off one section at a time
34
What is the overall goal of oxygen therapy?
Maintain adequate tissue oxygenation while minimizing cardiopulmonary work (reduce the work on the heart)
35
What are the normal adults values of PaO2 and SpO2?
PaO2 - 80-100 mmHg (ABG)
SpO2 - 95-99% on room air
36
Does oxygen treat breathlessness and can we have too much oxygen?
Oxygen doesn't treat breathlessness, only hypoxia, and we can have too much oxygen
37
What are some symptoms of oxygen toxicity?
Vasoconstriction and decreased cardiac output (PaO2 > 300 mmHg)
38
What is depression of ventilation and who is affected by this?
Decrease in ventilation of about 20% and COPD patients (patients get lethargic and confused)
39
What is retinopathy of prematurity and who is affected?
Abnormal eye condition in premature and low birth rate babies who receive supplemental O2, can lead to blindness
40
What is fixed vs. variable FiO2?
Fixed- system provides all of the patients inspired gas
Variable- system only provides some of the inspired gas and the patient must draw (or entrain) the remainder from surrounding air
41
What are the 3 types of oxygen therapy designs and are each one variable or fixed?
Low flow (variable), high flow (fixed) and reservoir (variable)
42
What are the different types of low flow systems and what L/m are they prescribed at?
Nasal cannula, nasal catheter and transtracheal catheter
8 L/m or less
43
What flow rates are used with a nasal cannula and what FiO2 is delivered? When do we use a humidifier?
1 L/m = 24%
2 L/m = 28%
3 L/m = 32%
4 L/m = 36%
5 L/m = 40%
6 L/m = 44%
>4L/m
44
What are some safety hazards for oxygen and what does NOT affect safety?
Smoking, Vaseline, electronics
Lead- based products DO NOT affect
45
What are advantages of high and low flow devices?
High flow guarantees the patients needs and low flow has an ease of use (comfortable, eating, moving around)
46
What is the best way to identify what gas is in a tank?
Label
47
What is the difference between hypoxia and hypoxemia?
Hypoxia- low level of oxygen in the tissue
Hypoxemia- low level of oxygen in the blood
48
What is a reservoir system and what types are there?
Incorporates a mechanism for gathering and storing O2 between breaths to draw extra flow from when their inspiratory flow exceeds the flow coming from device
Reservoir cannulas, masks and non-rebreathing circuits
49
What are the most commonly used reservoir systems and what are the three types?
Simple masks, partial rebreathing mask and nonrebreathing mask (all low flow)
50
What is the L/m used with a simple mask (and %) and what is the most common hazard?
5-10 L/m (35-50%)
Must be used with a minimum of 5 L/m
Aspiration
51
What FiO2 does the partial rebreather deliver and are there valves? What does flow rate start at?
40-70%, no valves, 10L/m
52
What FiO2 does the non rebreather deliver and how many valves?
60-80% with 2 valves
90-100% with 3 valves
10L/m and adjust so that bag doesn't collapse
53
In rebreathers and non-rebreathers, how is the flow rate and % ordered?
By the name of device
54
When is a non rebreather (one with the bag) indicated?
Emergencies and when delivering Heliox
55
When do we use High Flow vs. Low Flow?
High flow is used if breathing pattern is erratic or the RR > 25. We use low flow when the tidal volume is 300-700 ml and they have a normal RR and breathing pattern
56
What are high flow devices?
Air entrainment mask, air entrainment nebulizer, high flow nasal cannula (HFNC) and blending systems
57
What L/m qualify a device as a high flow?
60 L/m
58
What is the Venturi/ Bernoulli/ Air entrainment principle?
The velocity of the fluid increases as it flows through the narrower tube while the pressure decreases, due to conservation of energy.
59
How is the liter flow determined by an air-entrainment mask?
Liter flow is determined by the manufacturer
60
In air entrainment mask, what does changing the flow meter setting do to the flow and FiO2?
It alters the output flow but has little effect on set FiO2
61
What percentage of oxygen does the air entrainment mask provide?
24-50%
62
What happens when more air is entrained in a mask?
Total output flow is increased but the delivered O2 is decreased
63
Difference between high flow and low flow systems?
High flow is guaranteed to meet the patients need
64
In a low flow system, what happens when the patient is shallow breathing?
The oxygen percentage will increase
65
In a low flow system, what happens when the patient is breathing fast and heavy?
The oxygen concentration will decrease
66
The bigger the port size...
The more air and the less oxygen
67
The smaller the port size...
The less air and the more oxygen
68
What range of flow and FiO2 does the high flow nasal cannula provide?
Flow- 30-60 L/m
FiO2- 21-100%
69
What 3 components do HFNCs require?
A patient interface (nasal prongs or nasal cannula), a gas delivery device that regulates FiO2 and a humidifier
70
In what situations do we use a simple O2 mask? What flowrate and O2 %?
We use this short term, for mouth breathers or for surgery.
Flowrate- 5-10 L/m
O2 %- 35-50%
71
In what situations do we use a partial rebreathing mask or a non-rebreathing mask? What flow rate and O2 %?
We use this for traumatic injuries, smoke inhalation, MVAs (not for long term use)
Flow rate- min 10 L/m
Partial O2 %- 40-70%
Non-Rebreather O2%
w/ 1 side valve- 60-80%
w/ 2 side valve 90-100%
72
In what situations do we use a air-entrainment mask (Venturi)? What flow rate and O2%?
We use this when we need an exact oxygen concentration.
Flow rate- 4-12 L/m (based on manufacturer)
O2%- 24-50%
73
What are the 3 P's?
We use this when selecting a device
Purpose
Patient
Performance
74
When do we use a blending system?
When air entrainment can't provide a high enough gas concentration or flow (when we need an EXACT concentration)
75
What would we use an oxyhood for and what needs used in conjunction with this?
They are used for infants and need analyzed close to the babies face for accurate O2 %
Use with WICK humidifier
76
What would we use a mist tent for?
A child but frequent analyzing needed from the opening of the tent
77
What are some indications for hyperbaric oxygen therapy?
Carbon monoxide poisoning, wound healing, decompression sickness
78
What is one of the benefits of nitric oxide therapy ?
Lowers pulmonary hypertension
79
What are some benefits of heliox therapy?
Decreased RR, level of dyspnea and need for intubation for patients with croup, stridor, etc.
80
What is the definition of humidity?
Water in a vaporous or molecular form
81
What is absolute humidity?
the amount of water in a given volume of gas (expressed in mg/L)
82
What is relative humidity?
the ratio of actual water vapor content to its saturated capacity at a given temperature (expressed in percentage)
83
Air that is fully saturated with water vapor (100%) at 37 degrees C and 760 mmHg barometric pressure has water vapor pressure of ______ and absolute humidity of ______
water vapor pressure of 47 mmHg
absolute humidity of 44 mg/L
84
What is humidity deficit?
amount of water vapor that the body must add to a gas in order to achieve 100% humidity at a body temp
85
Explain gas flowing through a tube, what happens in relation to temperature and condensation.
Room air causes condensation to occur. Since the temperature of the room air is cooler, vapor will turn back into liquid.
86
Providing inadequate humidity to a patient can result in what?
Atelectasis or pneumonia due to retained secretions
87
What is the effect of water in the tubing?
Concentration of gas will increase due to less air mixing with it
Flow will decrease due to less room available for air to go through
88
How can we eliminate condensation in tubing?
Water drainage bag or draining tubing
89
What does a humidifier do?
Adds molecular water to gas
90
What are the 3 types of active humidifiers?
Bubble
Passover (reservoir) - WICK
Vaporizer
91
When do we use a bubble humidifier and do we heat it?
For flows greater than or equal to 4 L/m and it typically isn't heated
92
When do we use a tandem set up?
If the desired O2 is >60% to assure that the total flow meets or exceeds patient's peak inspiratory flow needs
93
What should the total flow be on a tandem set up?
Greater than or equal to 3 times the minute volume (generally 40-60 L/m)
94
What will low water levels do to a humidifier?
Decrease the efficiency of the humidifier
95
What do we need to do to assure the effective set up of a humidifier?
Occlude or pinch the tubing and listen for a chirp
96
What do we use the Passover type humidifier for?
Used with mechanical ventilator, CPAP and high flow nasal cannula
97
What are three types of Passover humidifiers?
Simple reservoir, Wick and membrane
98
What is the best type of humidifier in most (if not all) situations?
WICK- provides 100% humidity
99
What does HME stand for and what does it do?
Heat moisture exchangers and it is an "artificial nose" and ideal for patient transport, short term vent use or short term surgery
100
When should we NOT use an HME?
With thick or bloody secretions or a high minute volume
101
What is the role of a diffuser in a bubble humidifier?
The diffuser tube exposes the gas to the water and makes the bubbles
102
What is the difference between humidity and aerosol?
Humidity is just moisturized air, not actual particles. Aerosol is particles suspended in gas (bland aerosol, meds, etc)
103
What are goals of bland aerosol therapy and how do we receive this therapy?
Relieve bronchospasms, thin mucus, humidify respiratory tract and administer drugs
Through a nebulizer
104
What is the biggest hazard of aerosol therapy?
Pseudomonos
105
What is an USN used frequently for? What is the device powered by?
Used frequently for sputum induction and it uses a piezoelectric crystal
106
What are the 4 different airway appliances that can be used with a LVN?
Aerosol mask, face tent, t-tube or trach mask
107
What do we need to heat a bypassed airway to and why?
37 degrees C to prevent burns
108
What does it mean when the mist is disappearing on inspiration with an aerosol set up? What do we do to fix it?
This indicates that the patient isn't getting enough flow. We would increase the flow, add a tube, or add a tandem
109
How does the O2 concentration affect the density and flow?
Higher O2 concentration- less total flow and more dense
Lower O2 concentration- more total flow and less dense
110
What is the best way to confirm patient is getting adequate aerosol?
Watch mist coming out of tubing on inspiration
111
What do we do if aerosol is produced in short puffs?
Drain the tubing of condensation
112
What equipment is needed for application of a trach collar or T Tube?
Nebulizer, device being used (mask, face tent, etc.), thermometer, water collection bag, O2 analyzer and heater
*Also tandem set up if over >60%
113
When using blender to get desired FiO2 with LVN what do we set the blender and air entrainment port to?
Set blender to desired FiO2 and set port to 100%
114
What is a baffle and what is its purpose?
Anything inside the device and its purpose is to take away the large particles
115
What do we use a bleed in for?
To get the exact concentration when we are unable to get desired concentration with a nebulizer alone
116
What device would we use with upper airway swelling (subglottic edema)?
Cool aerosol LVN
117
What device would we use when our patient has hypothermia?
Heated aerosol or humidifier
118
What device would we use to hydrate excessive secretions?
LVN or USN
119
What are the indications for Home O2 prescription? (PaO2 and SpO2)
PaO2 - < 55 mmHg
SpO2 - < 88%
120
How do we assess our PaO2, SaO2 and SpO2?
PaO2 - ABG
SaO2 - ABG
SpO2 - pulse ox
121
How can you determine oxygen toxicity?
PaO2 and exposure time
122
What are the physical responses of oxygen toxicity?
Substernal chest pain, coughing, restlessness, hypertrophy, decreased lung compliance, decreased lung surfactant, etc.
123
How do we administer oxygen to avoid oxygen toxicity?
Lowest possible FiO2 (maintain FiO2 below 50-60%) but DON'T withhold oxygen if needed
124
Who does depression of ventilation effect and how? What is one way we can avoid depression of ventilation?
It affects a very small percentage of COPD patients when breathing moderate to high O2 concentrations
Use lowest flow possible with COPD patients
125
What are the signs of depression of ventilation?
Confused, lethargic, decreased RR, decreased chest expansion
126
Is hypoventilation typical in COPD patients?
No, so O2 to avoid hypoxemia should always be a priority
127
Do we measure FiO2 or PaO2 to determine retinopathy of prematurity?
We measure PaO2, not FiO2. Keep between 40-60 mmHg
128
Who is at greatest risk of absorption atelectasis?
Post-op, sedated patients, CNS dysfunction and retained secretions
129
What is the normal values for PaO2 and PaCO2?
PaO2 - 80-100 mmHg
COPD PaO2 - 50-65 mmHg
PaCO2 - 35-45 mmHg
130
What is the normal values for SaO2 and SpO2?
SaO2 - 95-100%
SpO2 - 94-100%
131
CHART for PaO2
< 80mmHg - hypoxemia
>100 mmHg- hyperoxemia
80-100 mmHg- normal
132
Hypoxemia classifications
Severe, moderate and mild
<40 mmHg - severe
40-59 mmHg- moderate
60-79 mmHg- mild
133
What is the use of the capillary tube in a nebulizer?
The capillary tube draws up water and makes little particles from the velocity of the jet stream, similar to a diffuser in bubble humidifier
134
What happens to the HR and RR in hypoxemia?
Increased HR and RR due to the increased work on the heart
135
What effect does the peripheral chemo-receptors have on depression of ventilation?
Peripheral chemoreceptors are sensitive to a decrease in oxygen level
136
What do we use for suspected carbon monoxide poisoning to measure the SpO2?
Co-oximetry
137
What does a pulse oximeter measure?
the O2 in the blood carried by the hemoglobin (SpO2)
138
How does pulse oximetry work?
Uses 2 light sources (red and infrared) that are absorbed in hemoglobin
139
Can we use a pulse oximeter on a pulseless patient?
No
140
Can anemia affect pulse ox?
Yes
141
What should we do if we are unsure of the reading from a pulse ox?
Get ABG
142
What should we always do first before anything else with an oxygen analyzer?
Calibrate to room air and 100%
143
What has the biggest effect on accuracy with an O2 analyzer?
Altitude
144
What effect does moisture have on an O2 analyzer reading?
It will cause the reading to be lower (condensation)
145
What is the first thing we do when we are told a patient needs oxygen?
Check the order!
146
Are cylinders used for large or small volumes of gas for home use?
Small (prevents waster of oxygen) and commonly used as back up
147
What are the flow rates used with liquid O2?
1-8 L/m
148
Do concentrations increase or decrease with higher flows from oxygen concentrators?
Decrease because there is not as much time for air to move through the sieves
149
What device can you not use with an oxygen concentrator and why?
Venturi mask because of back pressure
150
What are 2 advantages of home O2 concentrators?
They last a long time and don't need refilled
151
What is one disadvantage of home oxygen concentrators?
They are less pure so we may need to up the flow
