Monitoring Flashcards
1
Q
Standard 9 for Nurse Anesthesia Practice
A
Monitoring, alarms
2
Q
5 parts of Standard 9
A
- Oxygenation (pulse ox)
1. monitor ventilation (SpO2, ETCO2)
2. monitor CV status continuously
3. monitor thermoregulation continuously (MH triggers)
4. monitor NM function (NMBs)
5. monitor & assess patient positioning
3
Q
Monitor alarms must:
A
- variable pitch
- reflect changes in patient or equipment status
- threshold alarms on and audible
4
Q
Pulse Ox uses what law?
A
Beer-Lambert
5
Q
What is the wavelength of deoxyhemoglobin?
A
660nm
6
Q
What is the wavelength of oxyhemoglobin?
A
940nm
7
Q
Order of pulse ox sites
slowest → fastest
A
toe → finger → nose
8
Q
What is the PaO2 of oxygen when SpO2 is 90%?
A
60mmHg
9
Q
What is the PaO2 of oxygen when SpO2 is 80%?
A
50mmHg
10
Q
What is the PaO2 of oxygen when SpO2 is 70%?
A
40mmHg
11
Q
What are factors that alter SpO2?
A
- CoHb (falsely high reading) or MetHb (false ↑ or ↓)
- ambient light/high intensity
- tremors/vibration
- methylene blue (gives the largest DECREASE; pulse ox will overestimate), indigo carmine
- decreased perfusion
- deeply pigmented skin
- fingernail polish
- non-pulsatile flow (CBP, LVAD)
- electrocautery
- ## hypothermia
12
Q
What are the two “methods/location” of ETCO2 monitoring?
A
Mainstream (in-line)
Sidestream (diverting)
13
Q
Describe mainstream ETCO2
A
device attached to ETT
- increased dead space & weight
14
Q
Describe sidestream ETCO2
A
device located outside of airway
- pumping mechanism & water trap
15
Q
What occurs in phase 1 of capnogram?
A
exhalation of anatomic dead space- reading should be ZERO
16
Q
What occurs in phase 2 of capnogram?
A
exhalation of anatomic dead space & alveolar gas;
beginning expiration
17
Q
What occurs in phase 3 of capnogram
A
exhalation of alveolar gas;
should be horizontal with mild upstroke
- steepness is function of respiratory resistance (COPD, Bronchospasm)
18
Q
What occurs in phase 4 of capnogram
A
inspiration of fresh gas
19
Q
Where are the alpha & beta angles of the capnogram located?
A
_______
/a b\
___/ \___
20
Q
What is the degree of a normal alpha angle on the capnogram?
A
100-110degrees
21
Q
What are 4 factors that will increase the alpha angle?
A
[prolonged upstroke]
- expiratory airflow obstruction
- COPD
- Bronchospasm
- Kinked ETT
22
Q
What is the degree of a normal beta angle on the capnogram?
A
90degrees
23
Q
What are 2 factors that will increase the beta angle of the capnogram?
A
- rebreathing
2. faulty unidirectional valve
24
Q
What is a curare cleft?
A
spontaneous breathing during ventilation / inadequate muscle relaxation / dyssynchronous intercostal muscles & diaphragm
25
When does a low ETCO2 tracing occur?
hyperventilation
↓ CO2 production
↑alveolar dead space
- light anesthesia metabolic acidosis, hypothermia, hypotension, PE
26
What are factors that will increase ETCO2
MH, sepsis, fever, hyperthyroidism, hypoventilation, narcotics
27
What causes an elevated baseline on the ETCO2 tracing?
rebreathing
28
How will an incompetent unidirectional valve present on the ETCO2 tracing?
increased beta angle
- tracing may or may not reach baseline, depending on FGF
29
What will cause a "peak" in phase 3 of the ETCO2 tracing?
leak in the sample line during positive pressure ventilation
- obesity
- pregnancy
30
What electrical event coincides with the p-wave?
depolarization of the atria begins
31
What electrical event coincides with the PR interval?
depolarization of the atria is complete
32
What electrical event coincides with the QRS?
repolarization of the atria, depolarization of the ventricles begins
33
What electrical event coincides with the ST segment?
depolarization of the ventricles is complete
34
What electrical event coincides with the T wave
repolarization of the ventricles begins
35
What electrical event coincides with after the t wave
repolarization of the ventricles is complete
36
What are 5 pathologies that cause right axis deviation?
```
COPD
Acute bronchospasm
Cor pulmonale
Pulmonary HTN
Pulmonary embolus
```
37
What are 5 pathologies that cause left axis deviation?
```
Chronic HTN
LBBB
Aortic Stenosis
Aortic Insufficiency
Mitral Regurgitation
```
38
What degrees coincides with normal EKG axis?
-30 to 90
39
What degree coincides with left axis deviation?
-90 to -30
40
What degree coincides with right axis deviation?
90-180
41
What degree coincides with extreme right axis deviation?
180 to -90
42
What are 5 monitoring sites of invasive ABP?
radial, brachial, axillary, pedal, remoral
43
What indicates contractility on the ABP waveform?
upstroke
44
What on the ABP tracing indicates stroke volume?
area under the curve
45
What does the dicrotic notch indicate on the ABP tracing?
closure of the aortic valve
46
What partial pressure of oxygen correlates with 50% saturation?
25mmHg
47
Below what pulse ox number is it less reliable?
80-85%
48
What is the purpose of monitor alarms?
protect the patient by alerting the practitioner that the pt is at an increased risk and needs immediate assistance
49
What is the monitoring algorithm?
COVER-ABCD
50
What does COVER-ABCD (monitoring algorithm) stand for?
```
C- circulation, color
O- oxygen, oxygen analyzer
V - ventilator, vaporizer
E- ETT
R- Review monitors & equipment
```
A- Airway
B- Breathing
C- Circulation
D- Drugs
51
AANA Standard 9
monitor, evaluate, document the pts physiological condition.
When a monitoring device is used, VARIABLE PITCH & THRESHOLD alarms should be turned on and audible.
document BP, HR, RESP at least every 5 minutes
52
What does the oxygenation portion of Standard 9 entail?
continuous monitor by observation & pulse oximetry
- surgical or procedure team communicates & collaborates to mitigate risk of fire
53
Carboxyhemoglobin
90% oxyhemoglobin
10% deoxyhemoglobin
- pulse ox OVER-estimates saturation (not as high as the monitor thinks)
54
Methemoglobin
hemoglobin has been OXIDIZED
Ferous to Feric state (2+ → 3+)
does not bind oxygen = cannot deliver
- congenital (may be cyanotic) or acquired (can be severe or fatal; abrupt development of s/s. → hypoxia)
CAN CAUSE METHEMOGLOBINEMIA: Local anesthetics; topical sprays/creams; ped teething gel
Reglan; methylene blue
nitroglycerin
55
Monitoring of oxygenation includes which 4 devices/mechanism?
1. oxygen analyzer
2. clinical observation
3. pulse oximeter
4. arterial blood gas analysis
5. color of blood
56
During clinical observation of oxygenation, what is assessed?
- skin color
- temperature
- nail-bed perfusion
- depth & rate of respirations
- auscultation of breath sounds
- upper airway patency [see-saw; rtxn; WOB; stridor]
57
What 2 things does the pulse oximeter measure?
HR & SPO2
58
What is the goal of ventilation monitoring?
ensure adequate minute ventilation
59
What is evaluated when assessing ventilation?
adequacy & efficiency of the air/gas exchange
60
Monitoring of ventilation includes which 8 devices/mechanisms?
1. clinical observation
2. stethoscope (precordial)
3. RR
4. Tidal volume
5. ETCO2
6. Pulse oximetry
7. Oxygen analyzer
8. disconnect alarms
61
During clinical observation of ventilation, what is assessed?
- skin color
- temperature
- nail-bed perfusion
- depth & rate of respirations
- auscultation of breath sounds
- upper airway patency
62
What is capnometry?
all means of measuring CO2
63
What is capnography?
recording of the CO2 measurement
64
What is a capnogram?
continuous display of CO2 during the phases of ventilation
65
What is the goal ETCO2 during CPR?
10mmHG
66
During ABP monitoring, the further the catheter gets from the aorta... (4)
1. the taller the systolic peak
2. the further the dicrotic notch
3. the lower the end-diastolic pressure
4. the later the arrival of the pulse
67
What is the a point of the CVP waveform?
RA contraction
68
What is the c point of the CVP waveform?
tricuspid valve elevation into RA
69
What is the x point of the CVP waveform?
downward movement of contracting RV
70
What is the v point of the CVP waveform?
RA passive filling
71
What is the y point of the CVP waveform?
RA emptying through the open tricuspid valve
72
What is normal RA pressure?
0-10mmHg
73
What is normal RV pressure?
15-20/0-8
74
What is normal PAP?
15-30/5-15
75
What is normal PAOP
5-15
76
What is the a wave on a PA waveform?
LA systole
77
What is the c wave on a PA waveform?
Mitral valve into LA during LV systole
78
What is the v wave on a PA waveform?
passive LA filling
79
What are 6 body temperature monitoring sites?
```
bladder
pulmonary artery
esophageal
nasopharynx
tympanic
axillary
```
80
What nerve is best to measure onset of a NMBD?
orbicularis oculi
81
What muscle is best to measure onset of a NMBD?
facial nerve
82
What nerve is best to measure recovery from NMBD?
adductor pollicis
83
What muscle is best to measure recovery from NMBD?
ulnar nerve
84
TOF 4/4 indicates how much block?
<70%
85
TOF 3/4 indicates how much block?
75%
86
TOF 2/4 indicates how much block?
80%
87
TOF 1/4 indicates how much block?
90%
88
TOF 0/4 indicates how much block?
100%
89
Recovery from NMBD is defined as TOF > ___ at the adductor pollicis
0.9
90
What are 2 limitations of bispectral index?
1. 20-30 second lag
| 2. ketamine
91
BIS of 100 is
fully awake
92
BIS of 80 is
light/moderate sedation
93
BIS of 40-60 is
GA
94
BIS of 40 is
deep hypnotic state
95
BIS of 20 is
burst suppression
96
BIS of 0 is
absence of cerebral activity
97
What are the 6 elements of cardiovascular monitoring?
1. ECG rhythm
2. circulation
3. preload
4. afterload
5. contractility
6. hemodynamic status
98
What are 7 monitors/devices used in cardiovascular monitoring?
1. stethoscope
2. ECG
3. BP cuff
4. CVC
5. Arterial catheter
6. Pulmonary artery catheter
7. TEE
99
What are 3 things the ECG measures?
1. HR
2. rhythm
3. ST segment
100
What are benefits of monitoring lead II?
1. assesses narrow QRS complex rhythms
2. ST segment depression visible
3. detects inferior wall ischemia
4th intercostal space right sternal border
101
What is the benefit of monitoring lead V5?
detects anterior & lateral wall ischemia
5th intercostal space left anterior axillary line
102
Electrode placement
```
RA: 2nd inter Right MC line
LA: 2nd inter Left MC line
RL: 6-7 inter Right MC line
LL: 6-7 inter Left MCL
V: 4th inter Right sternal border
```
103
BP cuff should measure ___ greater than the mean diameter of the extremity
20%
104
A BP cuff that is too narrow will result in
high BP
105
A BP cuff that is too wide will result in
low BP
106
Normothermia is
37c
107
Hypothermia is
<36c
108
Hyperthermia is
>38c
109
What are the 4 mechanisms of heat loss?
1. radiation
2. evaporation
3. convection
4. conduction
110
Who is at high risk of thermoregulation issues?
- high ASA status
- long duration of surgery
- complex surgery
- combining epidural & GA
- advanced age
- lean body mass
- failure to monitor temperature
111
What are risks of hypothermia
- wound infection & delayed wound healing
- ↑O2 consumption d/t shivering
- ↑ cardiovascular incidents & MI
- ↑sickling in sickle cell patients
- prolonged PACU stay
112
What are 7 locations of core temperature measurement
1. tympanic membrane
2. distal esophagus
3. nasopharynx
4. pulmonary artery
5. bladder
6. oral
7. rectal
113
3 techniques to keep a patient warm
1. room temperature
2. forced air warming blankets
3. fluid warmers
114
Radiation
#1 loss of heat
Greatest heat loss is in the first hour.
transfer body heat into cooler environment
115
Evaporation
loss of liquids on the skin
116
Convection
Cool air moving over the body
117
Conduction
contact with a cooler object
118
How does the CRNA use inspection during monitoring?
LOOK
| retractions, color, mucous membranes
119
How does the CRAN use auscultation during monitoring?
heart and lung sounds, wheezing, continuous suction
120
What does the CRNA evaluate with palpitation during monitoring?
pulses, edema, crepitus, muscle tension, resistance, compliance
121
How does the CRNA use the sense of smell during monitoring?
smoke/burning, volatile anesthetics
122
What are the 5 standard categories of monitoring?
```
oxygenation
ventilation
cardiovascular
thermoregulatory
neuromuscular function
```
123
What is the AANA's standard 11?
transfer of care to another qualified healthcare provider
124
What is the most important aspect of anesthesia? per Dr. Simmons
AIRWAY
125
What is the fundamental goal of anesthesia, per Dr. SImmons?
avoid hypoxia
126
What does the O2 analyzer do?
measures FiO2 of inspired gas @ the inspiratory limb of the anesthesia circuit
127
What is the low concentration alarm of the O2 analyzer?
30%
128
The O2 analyzer is calibrated to what 2 oxygen percentages?
21% (room air)
| 100%
129
What is the alveolar gas equation?
PAO2 = FiO2 * (Pb-47) - PaCO2
ie.
PAO2 = 0.5*713 - 40
PAO2 = 317
130
What are the 2 mechanical parts of the oxygen analyzer called?
cathode
| anode
131
Where is the cathode located?
in the O2 analyzer
132
Where is the anode located?
in the O2 analyzer
133
The pulse oximeter provides what kind of a warning?
early & late
early: hypoxemia
late: cyanosis
134
What is plethysmography?
pulsatile measurement tracing
135
What is pleth variability? (Pvi)
indication of pulse strength of the pulse oximeter reading; 0-100
136
What is the Pvi good for?
fluid directed therapy
137
A SpO2 measurement of 60% is what partial pressure of oxygen?
PaO2 = 30mmHg
138
What SpO2 is used to indicate hypoxia?
<90%
139
What are the 2 components that make up ventilation?
1. movement of volume (inhale/exhale)
| 2. elimination of CO2
140
Where is a precordial stethoscope placed?
apex of lung or supra sternal notch
141
A precordial stethoscope does what?
Allows a provider to detect rapid changes in breath sounds or heart sounds;
anesthetic depth, circuit disconnections, endobronchial intubation, ↑HR, contractility
142
What is an esophageal stethoscope used for?
better quality heart and lung sounds;
| incorporated temperature probe
143
Where does an esophageal stethoscope placed?
intubated patients only,
through mouth or nose
ends at distal 1/3 of the esophagus
144
What are 2 contraindications of an esophageal stethoscope?
1. esophageal varices
| 2. esophageal strictures
145
What does a respiratory gas analysis do?
rates the absorbance characteristics of the gas sample;
| allows measurement of volatile anesthetics
146
What is the most common type of respiratory gas analysis?
non-dispersive infrared (NDIR)
147
Non-dispersive infrared respiratory gas analysis uses which type of sample collection?
side stream sampling
148
What is the volume of gas that is moved through the gas sampling line?
50-250mL/minute
149
Which monitor is the most effective in detecting circuit problems (ie. valves)?
ETCO2
150
What are 2 things ETCO2 monitoring does?
1. confirms ETT placement
| 2. used to assess if ventilation is adequate
151
Contamination of the side stream sampling by H2O will change the reading, up or down?
falsely ↑ readings
152
Rank arterial pp CO2, ETCO2, and alveolar CO2, from least to greatest
ETCO2 < alveolar CO2 < PaCO2
153
What is the normal PACO2 - PaCO2 gradient?
2-10mmHg
154
What are 7 causes of an abnormal PACO2-PaCO2 gradient?
1. gas sampling errors
2. prolonged expiratory phase
3. V/Q mismatch
4. airway obstruction
5. embolic states
6. COPD
7. Hypoperfusion
155
A low plateau on the capnography tracing indicates
↑ dead space, ↓Cardiac output
156
A high plateau on the capnography tracing indicates
high CO2 production;
| hypoventilation
157
An integrated ___ allows tidal volume monitoring with the mechanical ventilator
spirometer
158
What are 4 pressures that are monitored by the mechanical ventilator
1. in circuit pressure (via gauge)
2. peak inspiratory pressure
3. sustained elevated pressure
4. low airway pressure / disconnect alarm
159
Which ECG lead yields max p wave voltage?
Lead II
160
inferior wall ischemia is best detected by what lead?
Lead II
161
Anterior and Lateral wall ischemia are best detected by which lead?
V5
162
When do you hear Korotkoff sounds?
Manual BP
163
Accuracy of BP measurements decreases at what pressure?
70mmHg
164
What are 4 factors that can cause errors in BP reading?
1. surgeon leaning on cuff
2. inappropriate size
3. shivering or excessive movement
4. atherosclerosis/HTN (SYS reads low; DIA reads high)
165
What arterial line site increases risk of pseudoaneurysm & atheroma formation?
femoral
166
What arterial line site increases risk of increase difficulty?
Ulnar
167
What arterial line site increases risk of kinking or complications risking limb
brachial
168
What arterial line site increases risk of a distorted waveform?
dorsalis pedis
169
What arterial line site increases risk of plexus/nerve damage from hematoma or traumatic cannulation?
axillary
170
4 sites of insertion to monitor CVP
1. IJ
2. subclavian
3. external jugular
4. antecubital
171
What EF is considered poor function?
40%
172
What cardiac index is considered poor function?
2L/min/m^2
173
What are 5 indications for a pulmonary artery catheter
1. valvular heart dz
2. recent MI
3. ARDS
4. Massive trauma
5. major vascular surgery
174
A 70kg patient receiving 1L of room temperature fluid will decrease their body temperature by how much?
0.4c
175
A 70kg patient receiving one unit of room temperature blood will decrease their body temperature by how much?
0.2c
176
Spinal/epidural anesthesia has what effect on thermoregulation?
vasodilation below block = redistribution of heat
177
General anesthesia has what effect on thermoregulation?
inhibits central thermoregulation d/t disruption of hypothalamic function
178
Phase II of anesthesia alters perception of what, leading to hypothermia?
dermetomes
179
For each % isoflurane, the body's vasoconstriction threshold is dropped by how much?
3c
180
What is considered mild hypothermia?
33c-36c
181
What occurs in mild hypothermia?
- reduced enzyme function
| - coagulopathy
182
What is considered moderate hypothermia?
= 32c
183
During anesthesia, the body temperature may drop by ___
1c-4c
184
Who is at greatest risk of hypothermia intraoperatively?
elderly, neonates, burn patients, spinal cord injury
185
Comorbidities that limit oxygen supply may not tolerate, what?
Increased MVO2 (ie. shivering)
186
What are some causes of hyperthermia?
```
MH (late sign)
endogenous pyrogens
thyrotoxicosis or pheochromocytoma (↑metabolism)
anticholinergic blockade of sweating
excessive environmental warming
```
187
What are active warming modalities? (7)
```
Bair hugger
warming blanket
radiant heat unit
heated liquids
IV fluid warmer (Hotline)
gastric lavage
peritoneal irrigation
```
188
What are passive warming modalities? (
ambient temperature
insulation
heat & moisture exchanger (humidifier/"nose")
coaxial breathing circuit ("King" circuit)
189
Adequate NMB is what % of receptors
85-90%
190
What are 4 factors that can alter the reading of the peripheral nerve stimulator?
1. electrolyte imbalance
2. hypothermia
3. NM disorder
4 drugs
191
What are s/s of residual NMB?
```
hypoxia
↓TV
stridor
weakness
↑O2 requirements
```
192
During ulnar nerve monitoring, the black lead goes where?
flexor crease
193
With paralysis at the ulnar nerve, patient can still have
coughing, breathing, vocal cord movement
194
Facial nerve is CN ___
7
195
The facial nerve lies within what gland?
parotid
196
Is the facial nerve or ulnar nerve a better indicator of NMB of the diaphragm & airway?
facial
197
Posterior tibial nerve is monitoring which muscle?
flexor hallucis brevis = flex of big toe
198
Peroneal nerve is on the medial or lateral aspect of the leg?
lateral aspect of the knee/calf
199
Stimulation of the peroneal nerve results in ___
dorsiflexion of the foot
200
A normal twitch on TOF can be produced with up to what % of receptors blocked?
75%
201
Single twitch TOF is ___ every ___
0.1Hz - 1Hz every 10 seconds
| 1Hz will decrease time of detection (use on induction)
202
TOF is a __Hz stimulation every __
2Hz every 0.5 seconds (4 total = 2 seconds)
203
RATIO between twitch 1 and 4 is a sensitive indicator of
NM block
204
What type of blockade produces fade?
non-depolarizing
205
Depolarizing block will produce fade, T/F?
F
206
Tetanic stimulation is tetany at __ for ___
50-100Hz for 5 seconds
207
When TOF ratio is >70%, what will occur?????
sustained response????
208
Post-tetanic count
50Hz for 5 seconds
THEN
1Hz every second up to 20x
209
less twitches in a post tetanic count means
more block
210
Profoundly blocked is indicated by
no post-tetanic count
no single twitch
no TOF
211
Double burst stimulation
3 short 50Hz impulses; 750ms pause; another 3 short 50Hz pulses
- more sensitive than TOF and less painful than tetany
- #3 is most common, can use other
212
What 2 NM monitoring test for induction
single twitch
| TOF
213
What 2 NM monitoring tests for maintenance
TOF
| Post-tetanic count
214
What 2 NM monitoring for emergence
TOF
| Double burst stimulation
215
What nerve do we monitor for NMB onset?
facial
216
What nerve do we monitor for NMB recovery?
ulnar nerve
217
TOF 1/4, reversal may take up to how long?
30 minutes
218
TOF 2-3/4, reversal may take up to how long?
10-12 minutes following long-acting medication;
| 4-5 minutes following intermediate-acting medication
219
TOF 4/4, adequate recovery is after how long?
within 5 minutes of neostigmine;
within 2-3 minutes of edrophonium
220
6 unreliable signs of NMB recovery
- sustained eye opening
- tongue protrusion
- arm lift to opposing shoulder
- normal tidal volume
- normal or near normal vital capacity
- Max inspiratory pressure <40-50cmH2O
221
4 "most" reliable signs of NMB recovery
- sustained head lift x5 seconds
- sustained leg lift x5 seconds
- sustained hand grip x5 seconds
- max inspiratory pressure 40-50cmH2O
222
BIS monitor is used to assess:
the depth of anesthesia
223
4 advantages of the BIS monitor
- reduced risk of awareness
- better management of response to surgical stim
- faster wake up? (controversial)
- more cost effective use of meds/anesthetics
224
BIS >70
greater risk of recall
225
BIS reading must be interpreted ALONG WITH ___- & ____
SQI (signal quality index)
| EMG
226
The best BIS reading, includes ↑ or ↓ SQI?
↑SQI
227
The best BIS reading, includes ↑ or ↓ EMG?
↓EMG
228
What are 5 factors that may affect the BIS reading?
- patient movement
- electrocautery
- EMG
- pacer spikes
- EKG signal
229
What are 4 factors that can ↓ BIS reading?
- change in BP
- partial pressure of CO2 in arterial blood
- Hgb concentration
- regional blood volume
230
A patient with a falsely LOW BIS reading is:
moving, paced, anemic, hypotensive, hypercapnic, patient
231
The brain consumes what % of oxygen in the body?
20%
232
What is the goal cerebral oximetry reading?
MINIMUM is no less than 75% of baseline
233
What does a cerebral oximeter detect?
decrease in CBF in relation to CMRO2
234
More than 20% reduction in reading of the cerebral oximeter is correlated with what?
regional &/or global ischemia
235
What are 5 different types of quantitative nerve monitoring?
```
Acceleromyography (AMG)
Electromyography (EMG)
Kinemyography (KMG)
Mechanomyography (MMG)
Phonomyography (PMG)
```
236
What is Acceleromyography (AMG) NM monitoring?
muscle acceleration
237
What is Electromyography (EMG) NM monitoring?
muscle AP recorded;
| monitoring electrical activity proportional to muscle movement
238
What is Kinemyography (KMG) NM monitoring?
quantifies muscle movement with motion sensor strip
239
What is Mechanomyography (MMG) NM monitoring?
detects contraction force & converts it to an electrical signal
↑amplitude = ↑strength
240
What is Phonomyography (PMG) NM monitoring?
muscle contraction produces low frequency sounds; calculates muscle response
