Week 5: Rep. Monitoring, Ventilation and Capnography Flashcards
(122 cards)
1
Q
AANA and ASA standard of care
A
Continuous assessment of airway and breathing
2
Q
What does a precordial stethoscope do
A
Hear lung and heart sounds at the same time
3
Q
Why is a systemic approach to monitoring important and what does it entail?
A
Timely response
Habits of assessment avoids errors
“Sweep” the anesthesia field
4
Q
What does it mean to “sweep” the anesthesia field?
A
Always looking and listening to patient, checking vitals, watching monitors
5
Q
Crisis Management algorithm
A
COVERABCD
6
Q
C
(in COVERABCD and what it entails)
A
Circulation
Color, BP, ECG
7
Q
O
(in COVERABCD and what it entails)
A
Oxygenation
Check oxygen delivery system
8
Q
V
(in COVERABCD and what it entials)
A
Ventiltaion/Vaporizer
Ventilate by hand to assess breathing circuit and airway patency.
Assess chest rise
auscultate
assess ETCO2
check vaporizer function
9
Q
E
(In COVERABCD and what it entails)
A
Endotracheal tube
Asses patency, seal, position
10
Q
R
(In COVERABCD and what it entails)
A
Review Monitors
Review Equipment
Review Plan
11
Q
A
(In COVERABCD and what it entails)
A
Airway
Assess patency of unintubated airway, assess for laryngospasm, foreign body, air exchange
12
Q
B
(in COVER ABCD and what it entails)
A
Breathing
Quality
Pattern
Rate
Depth
Listen
Review ETCO2 and SPo2
13
Q
C
(in COVER ABCD and what it entails)
A
Circulation
14
Q
D
(in COVER ABCD and what it entails)
A
Drugs
review drugs given
15
Q
Important components of of airway monitoring
A
-Observe for gas exchange
-Subtle changes need intervention
-Verify placement
16
Q
Verify ETT or LMA by:
A
-breath sounds
-chest expansion
-ETCO2
17
Q
Muscular signs on airway issue
A
Seesaw
Stridor
Retractions
18
Q
Pulse oximetry measures
A
- Heart rate
- Percent of oxygen saturations of hemoglobin
19
Q
How does a pulse oximeter work?
A
Uses wavelengths of red and infrared light
oxygenated hgb and unoxygenated hgb absorb infared light at different wavelengths
one diode transits through tissue to oppositely place photosensitive diode that measures amount of absorbed red light
20
Q
Oxyhemoglobin dissociation curve expressess
A
Relationship between O2 tension and percent of O2 saturation
21
Q
P50 is:
A
PaO2 at which 50% of the Hgb is saturated
22
Q
Normal P50 adult
A
26-27
23
Q
Oxyhemoglobin dissociation curve rights shift = ______ p50
A
increaes
24
Q
Oxyhemoglobin dissociation curve left shift = ____ p50
A
decreases
25
oxyhemoglobin dissociation curve left shift means
Hgb has greater affinity for O2, does not want to give away
L=love
26
Greater affinity of Hgb for oxygen means ______ to tissue
Less oxygen
27
Oxyhemoglobin dissociation curve right shift means
Hgb has less affinity for O2, OK with giving it away
28
Less affinity of Hgb for oxygen means ____ to tissue
More oxygen
29
What causes a left shift of the oxyhemoglobin dissociation curve?
(CO2, temp, 2-3 DPG, pH)
Decreased CO2
Decreased Temp
Decreased level of 2-3 DPG
Elevated pH, alalosis
30
What causes a right shift of the oxyhemoglobin dissociation curve?
(CO2, temp, 2-3 DPG, pH)
Elevated CO2
Elevated Temp
Elevated levels of 2,3 DPG
Decreased pH, acidosis
31
SpO2 90% = PaO2 ____
(in nml ODC)
60
32
SPO2 80% = PaO2____
(in nml ODC)
80
and SPo2 70% is PaO2 of 40 and so on
33
If ODC sfhits right, p50 ___
increases
34
If ODC shfits left, p50 ____
decreases
35
General best area for SPO2 monitor
More central circulation
36
What can cause poor SPO2 reading?
-Motion artifact
-cold temps (vasoconstriction)
-Abnormal Hgbs
-Injectable dye
37
Metheglobin and oxyhemoglobin effect on SPo2 reading
if true SPO2 is less than 85%, reading can be overestimated
if true SPO2 is more than 85%, reading can be underestimated
38
What does pulse oximetry do (4)?
1. Provides percentage of hgb that is saturated by O2
2. Provides HR
3. Can monitor decreased perfusion
4. Predicts fluid responsiveness PPV
39
Pulse oximetry does NOT (3)
1. monitor DO2 or caO2
2. monitor VENTILATION (nml SpO2 in hypercarbia)
3. Monitor Anemia (can be anemic and be 100% saturated)
40
DO2
Oxygen delivery to alveoli
41
VO2
Consumption of oxygen by tissues
42
Boyle's law is a relationship between
Pressure and Volume
(as one increases, the other decreases)
43
As pressure increases, volume _____
decreases (and vice versa)
44
as pressure decreases, volume _____
increases (and vice versa)
45
When diaphragm and intercostals contract, what happens to the thoracic cavity?
How does this happen?
Sightly enlarges, so pressure is decreased
Diaphragm flattens and moves inferiorly while external intercostals elevate the rib cage and move sternum anteriorly
(We are expanding the container size)
46
Is 'quiet' expiration active or passive?
What happens?
Does this increase or decrease volume/pressure in thoracic cavity?
Passive process (diaphragm and external intercostal muscles relax)
elastic lungs and thoracic wall recoil inward.
Volume is decreased, pressure is increased in thoracic cavity
(we are shrinking the container size)
47
Deep/forceful expiration is active or passive?
Active process
dramatically decrease volume and increase pressure
48
As bronchus constricts, diameter ______ and resistances _____
Diameter decreases and resistance increases
49
As resistance decreases, airflow ____
Increases
50
Acetylcholine and airway resistance
PNS relaxes acetylcholine which CONSTICTS bronchioles = increased airway resistance
51
If acetylcholine is blocked, what happens to airway?
Airway relaxes!
52
Histamine and airway resistance
Histamine constricts bronchioles —>increases airway resistance —>decreases airflow
53
Epinephrine and airway resistance and airflow
Epi is released from adrenal medulla during exercise, stress—->dilates bronchioles—?decreases airway resistance—->increases airflow
54
Compliance equation
Change in volume
—————————
Change in pressure
55
Compliance definition
A measure of the distensibility of a chamber expressed AS A CHANGE IN VOLUME PER UNIT OF CHANGE IN PRESSURE
56
Two Factors determine lung compliance:
1. Stretchability of elastic fibers within the lungs
2. Surface tension within the alveoli
57
What does surfactant do?
lowers surface tension and increases lung compliance
without surfactant, alveoli can't open and close (alveoli resist expansion)
58
Dynamic compliance is a function of:
1. airway resistance
2. elasticity of the chest wall
59
Dynamic compliance equation:
Tidal volume
---------------------
Peak Inspiratory Pressure - PEEP
60
Static Compliance is a function of:
Elasticity of the chest wall only
NOT RESISTANCE
61
Static compliance equation:
Tidal volume
--------------------
Plateau Pressure - PEEP
62
Plateau Pressure is the:
Pressure applied to small airways and alveoli
63
Plateau Pressure is measured during:
inspiratory pause on the ventilator
64
Goal plateau is ____. Why?
<30-35 cm H2O.
To preent barotrauma
65
Without lung disease, compare peak expiratory pressure and plateau pressure
PIP is only slightly higher than PPlat. Will be very similar
66
What does increased resistance look like in terms of PIP and Pplat
increased peak pressures without increasing plateau pressures indicate INCREASED RESISTANCE
67
Does airway resistance effect PPlat? Why or why not?
Resistance does not effect Pplat because there is no airflow during that time (during inspiratory pause).
68
Plateau pressure reflects
the elastic recoil of the lungs and thorax (During inspiratory pause)
69
Complications of elevated plateau pressure:
1. lung injury
2. pseumomediastiunum
3. subcutaneous ephysema
70
PIP aka
Ppeak
71
Increased PIP and unchanged PPlat, problem is:
Increased inspiratory gas flow OR increased airway resistance
72
If PIP has increased and PP has no change, what has happened?
1. Resistance has increased
OR
2. Inspiratory flow rate has increased
73
If PIP and PPlat have increased, what has happened?
1. Total compliance has decreased
(Pelastic as increased)
OR
Tidal volume has increased
74
What do spirometry loops provide?
Rapid evaluation of changes in lunch compliance and resistance
75
Spirometry loops are a graphic representation of:
dynamic relationship between lung compliance and resistance
76
Pulmonary resistance looks at
flow and volume
77
Pulmonary compliance looks at
Pressure and Volume
78
The flow volume loop measures:
Pulmonary resistance by plotting Flow (L/sec and Volume (L)
79
Pressure volume loop measures
compliance by plotting Pressure (cm H2O) and Volume (L)
80
Pressure volume loop and what part of breathing cycle measures where
*reference notability study pages
81
PEEP effect on pressure volume loop (compliance)
WIth - increase of slope, better compliance
Without - Slope of curve less, low compliance. Lower inflection point
*reference notability study pages
82
What is PEEP?
Maintenance of positive pressure within the lungs at the end of expiration
(in spontaneous pt, equivalent to CPAP)
83
Why use PEEP?
Improves oxygenation by recruiting collapsed alveoli and decreasing shunt
84
Airway pressure caclulation
AIrway pressure = Flow x resistance + (alveolar pressure) + Peep
85
What does PEEP do?
Decreases airway resistance (negative pressure generated in lungs to draw in air) because it gives some pressure to begin with when pulling in air
*see PEEP video
86
PEEP contraindications (5)
1. Tension Pneumothorax
2. Hypovolemic shock
3. Bronchopleural fistula
4. High ICP
5. RV failure
87
Ventilation monitoring in anesthesia care evaluates:
BOTH ventilation and oxygenation
88
Ventilation monitoring in anesthesia care consists of (4):
-ensuring adequate minute ventilation of anesthetic (5-7) ml/kg ideal bodyweight
-Listening with precordial stethoscope to detect early changes
-Assessment of minute ventilation with rate and tidal volume
-determining patient changes to stimuli and response to drug administration (ex. rebreathing may need muscle relaxant re-dose, stimulation may need more narcotic)
89
Ways to monitor CO2 (2)
1.disposable ETCO2 (colorimetric)
2. ABG
3. Continuous measurement of CO2 in expired gas (gas line monitor)
90
Disadvantages of ETCO2
false positives and false negatives
91
Gas line monitor gives:
An accurate, continuous reflection of arterial blood CO2
92
ETCO2 in gas line monitor (continuous) measurement is _______ than PaCo2 in normal heart and lungs
2-5 torr mmhg LOWER
93
How is continuous measurement of ETCO2 obtained?
Infared analysis: Each gas in mixture absorbs infared radiation at different wavelengths
94
Nondiverting CO2 sampling line measures
directly from mainstream/ it is inline
gas passes between anesthesia circuit and mask adapter
95
diverting/sidestream CO2 sampling line measures
gas from sample line tubing attached to circuit near patient and flows to monitor
gas needs scavaging
96
ETCO2 Capnography records:
CO2 as expired lung volume throughout the phases of respiration plotted against time
97
Time capnography can:
differentiate between normal and abnormal patterns of ventilation
(reference study notability doc)
98
The shape of ETCO2 capnography can vary:
1. based on mode of airway management (ETT, LMA etc.)
2. Pt spontaneously breathing or being ventilated
99
Phase one of ETCO2 capnog reflects ____ and should be ____
Anatomic dead space (no CO2), should be 0
100
Phase 2 ETCO2 capnog is the _____ and contains _____
Expiratory upstroke, mix of dead space and alveolar gas
101
Phase 3 ETCO2 capnog
Represents plateau/alveolar emptying
102
Phase 4 ETCO2 monitoring
Rapid decrease in CO2 as a result of inspired air or O2
103
*See notability study doc for details and labeling practice
104
Normal alpha angle is (Degrees)
100-110 degrees
105
Increased alpha angle means
Expiratory flow obstruction
106
Beta angle should be ___ degrees. Why?
90 degrees.
Shows inspiration, capnograph should return quickly to 0
107
If beta angle is increased, could mean (3):
1. rebreathing
2. Faulty inspiratory valve
3. normal with exhausted CO2 absorber
108
Causes of increased CO2 on capnographhy (3)
1. From increased CO2 delivery/production
2. Hypoventilation (withholding)
3. Equipment problems
109
Causes of decreased CO2 on capnography (3)
1. Decreased CO2 deliver/production
2. Hyperventilation
3. Equipment problems
110
Two main base ventilator pathways:
1. Volume Controlled
2. Pressure controlled
*all ventilator modes are a combination of these 2 systems
111
Volume controlled mode attempts to ______ and ______ is variable based on _____
Achieve a pre-set TV.
Peak airway pressure is variable based on resistance, compliance.
112
Pressure controlled mode attempts to ____ and _____ is variable based on ____
Achieve preset pressure
variable tidal volume that is based on resistance and compliance
113
LMA is usually ____ mode of ventilation
Pressure mode
114
Peak Airway Pressure (PAW) iss:
the total pressure needed to deliver the tidal volume
115
Plateau Pressure (PPlat) is:
the pressure needed to distend the lungs
116
Sensitivity or trigger sensitivity is:
Effort of negative pressure required by the patient to trigger the machine to breath
117
Venous blood is captured by (in SpO2)
near infared light 940 nm
118
Arterial blood is captured by (in SpO2)
Red light 660nm
119
Oxy-hemoglobin dissociation curve axes
x: PaO2 (partial pressure of oxygen in blood)
Y: SaO2 (O2 saturation)/ SpO2
120
P50
partial pressure of oxygen at which our pulse oximeter reads 50%
121
Pressure dissociation curve tell us
At what pressure will oxygen dissociate from Hgb
122
