Vent material Flashcards
1
Q
A
restriction
2
Q
A
airway obstruction
3
Q
A
fixed obstruction
4
Q
A
variable intra thoracic obstruction
5
Q
A
early airflow obstruction
6
Q
A
variable extra thoracic obstruction
7
Q
A
normal flow volume loop
8
Q
spirogram
A
9
Q
wright respirometer
A
10
Q
3 types of dead space
A
11
Q
what is I TIME
A
amount of time spent in inspiration
12
Q
what is E time
A
amount of time spent in expiration
13
Q
what is volume
A
the amount of tidal volume a patient recieves
14
Q
what is pressure
A
measure of impedence to gas flow rate
15
Q
what is flow
A
measure of rate at which gas is delivered
16
Q
what is the ideal amount of tidal volume
A
6-8ml/kg of ideal body weight
17
Q
when do you give lower TVs
A
ARDS or COPD or ASTHMA
18
Q
what is PIP
A
peak inspiratory pressure
the highest level of pressure aplied to lungs in cm H2O
19
Q
what is PIP limit
A
40 cmH2O
20
Q
when can PIP be higher
A
ARDS
21
Q
what should PIP be in masked or LMA patient
A
20 cmH2O
bc lower esophageal sphincter opens at >20cmH20
22
Q
what triggers a ventilator to cycle inspiration
A
time
pressure
volume
flow
23
Q
what is a normal peep level
A
5-8 cm h2o
24
Q
what conditions require higher peep of 8-12 or 20 cm H2O
A
ARDS
25
what happens if PEEP exceeds 20 cm H20
severe lung damage
barotrauma
subq emphysema
pneumo
26
slope is a measure of
time
27
slope is how long it takes to reach a set
pressure
28
what is range of slope
0-2 seconds
29
a higher number slope is a more (gradual/steep) slope
gradual
30
what mode is slope important in
pressure support
31
if slope is longer than inspiratory time what is comprimised
TV
32
what is PIP- PEEP
delta P
33
pressure control is
preset pressure
delivered Vt changes according to lung compliance
when the patient is spontaneously breathing, as the PIP is fixed, reduces pt discomfort
34
volume control is
volume is preset
delivered PIP varies based on pulm compliance and airway resistance
pt spontaneously breathing, PIP is variable, it will deliver a breath during asynchrony leading to increased work of breathing and discomfort
35
pressure vs volume waveforms
36
which vent mode provides guaranteed MV and is more comfortable for patients
volume control
37
which vent mode is not optimal for poorly compliant lungs
volume
38
which vent mode provides more support at lower PIP for poorly compliant lungs
pressure
39
which vent mode does not have a guaranteed MV
pressure
40
which vent mode do we use right before extubation
pressure support
41
which vent mode is pressure support but with a BACKUP rate
PSV-pro
42
which vent mode has madatory breaths (synchronized) and pressure support for spontaneous breaths
SIMV
43
what flow is diminished in COPD
expiratory
FEV1 is low
44
normal flow volume loop
45
COPD flow-volume loop
46
how does restrictive lung disease affect volume loop
residual volume is low
inspiratory volume (TLC)
FEV1 normal
peak exp flow normal
47
restrictive flow-volume loop
48
flow volume loop comparison
49
what would cause a pattern of expiratory flow-volume curve to be normal, but have a low inspiratory value
upper airway obstruction
50
what causes upper airway obstruction
paralysis of vocal cords
laryngospasms
Thyromegaly
tracheomalacia
51
what complication obstructs both inspiration and expiration
fixed intrathoracic or extrathoracic airway obstuctions
EX. tracheal stenosis, foregn body, neoplasm
52
what is a cause of post op bradypnea
opioid overdose
53
what is a cause of post op tachypnea
pain
54
as TV decreases, dead space____
increases
55
what must be set in VCV mode
TV
RR
I:E ratio
56
PIP is ____ related to lung compliance
inversely
57
what is set in PCV
peak airway pressure
RR
I:E ratio
58
what must be monitored closely in PCV
tidal volume
CO2
59
what is the amount of gas inspired or expired with each normal breath
Tidal Volume (TV)
60
what is the maximum amount of additional air that can be inspired from the end of a normal inspiration
inspiratory reserve volume
61
what is the maximum volume of additional air that can be expired from the end of a normal expiration
expiratory reserve volume
62
what is the volume of air remaining in the lung after a maximal expiration
residual volume
63
what s the only lung volume which cannot be measured with a spirometer
residual volume
64
what is the volume of air contained in the lungs at the end of a maximal inspiration
total lung capacity
65
what is the sum of the 4 basic lung volumes
TLC
IRV+TV+ERV+RV
66
what is the maximum volume of air that can be forcefully expelled from the lungs following a maximal inspiration
vital capacity
67
what is the sum of inspiratory reserve volume, tidal volume and expiratory reserve volume
vital capacity
68
what is the formula for VC
IRV+TV+ERV= TLC-RV
69
what are some factors that decrease FRC
obesity
pregnancy
upright position
supine position
anesthetic induction
neuromuscular blockers
surgical displacement
70
what is the reservoir of oxygen that prevents hypoxemia during apnea
functional residual capacity
71
what is the volume of air remaining in the lung at the end of a normal expiration
functional residual capacity
72
what is the residual volume plus the expiratory reserve volume
FRC
73
what is the fomula for FRC
RV + ERV
74
how does GA affect FRC
decreases
75
how does obesity affect FRC
decreases
76
how does pregnancy affect FRC
decreases
77
how is FRC in neonates
decreased
78
how does advanced age affect FRC
increases
79
how does supine position affect FRC
decreased
80
how does lithotomy affect FRC
decreases
81
how does trendelenburg affect FRC
decreases
82
how does prone affect FRC
increases
83
how does sitting affect FRC
increases
84
how does lateral position affect FRC
no change or increases
85
how does paralysis affect FRC
decreases
86
how does inadequate anesthesia affect FRC
decreases
87
how does excessive IV fluids affects FRC
decreases
88
how does high FI02 affect FRC
decreases
89
how does reduced pulmonary compliance affect FRC
decreases
90
how does obstructive lung disease affect FRC
increased
91
how does PEEP affect FRC
increased
92
how do sigh breaths affect FRC
increased
93
what is the maximum volume of air that can be inspired from end expiratory position
inspired capacity
94
what is the sum of tidal volume and inspiratory reserve volume
inspired capacity
95
what is the formula for IC
tidal vol + inspiratory reserve volume
96
which lung zone has no blood flow
zone 1, pathological zone
97
in what lung zone does pulmonary pressure exceed alveolar pressure. blood flow here is pulmonary artery pressure-alveolar pressure
zone 2
98
what lung zone is blood flow proportional to PAP- pulmonary vein pressure
zone 3
99
where should Swan be
zone 3
100
which zone is present in pulmonary edema
zone 4
101
blood flow in zone 4 is PAP- ___________
pulmonary interstitial fluid pressure gradient
102
which lung zone is:
PA(alveolar)>Pa>Pv
zone 1
103
which lung zone is:
Pa>PA>pv
zone 2
104
which lung zone is:
Pa>Pv>PA
zone 3
105
which lung zone is:
Pa>Pi (interstitial pressure)> Pv>PA
zone 4
106
what is normal Va (alveolar ventilation)
4 L/ min
107
what is normal pulmonary capillary perfusion (Q)
5 L/min
108
what is normal V/Q ratio
0.8
109
what is normal V/Q range
0.3-3.0
110
what causes a low V/Q ratio
LUNG PROBLEM
shunt
airway obstruction to area
111
what causes a high V/Q ratio
BLOOD PROBLEM
deadspace
blood flow problem
pulmonary emoboli
112
low v/q
113
high V/Q
114
what is the affect of shunt/low V/Q
hypoxia
115
what is the affect of deadspace high V/Q
hypercapnea
hypoxia
116
shunt
117
dead space
118
in shunt:
PaO2 is __________
PaCO2 is ___________
Low
High
119
in pulmonary embolism (dead space):
PAO2 is_________
PACO2 is _________
higher
low
120
mapleson circuits
121
bain circuit
122
at what flow do you not need a CO2 absorber on circuit
>5L
123
where is dead space on a circle cicuit
distal to Y piece
124
what gives lungs their elasticity
collagen and elastin fibers
125
lungs with low compliance require (less/more) pressure to inflate
more
126
what is the elastance formula
127
what is compliance formula
128
what causes resistance in the lungs
tissue resistance and airway resistance
129
what law gives us the formula for resistance
poiseuilles law
130
poiseuilles law pressure formula
131
what does an increased alfa angle suggest
expiratory airway obstruction
-copd, bronchospasm, kinked et tube
132
what can cause increased dead space causing low etco2
pulm embolism
133
what does an increased beta angle suggest
rebreathing due to faulty inspiration valve
soda lime
134
what needs to be monitored when giving neuromuscular blocking agents
neuromuscular function and status
135
what are advantages of side stream sampling
lightweight,
less chance of disconnect,
accurate <40 breaths/min,
no dead space
136
what are disadvantages of side stream monitoring
water/secretions may clog line,
flexible tube easily obstructed,
inaccurate >40 breath so no peds
137
describe side stream sampling
pump in monitor aspirates sample of gas trhough thin/flexible sampling line
138
what monitoring sampling measures gas directly in breathing system
mainstream aka non diverting
139
what are advantages of mainstream sampling aka non diverting
fast,
good fidelity,
water and secretions not an issue
140
which sampling method can increase etco2
mainstream sampling by increasing dead space
141
what are disadvantages of mainstream sampling aka non diverting
heavy in circuit,
increases dead space,
greater opportunity for disconnect,
gas options limited
142
what is the measurement and numerical display of co2 concentrations during respiratory cycle
capnography
143
what is a graphic record of co2 concntratino on screen or paper
capnography
144
what is the actual waveform genered by capnometer
capnogram
145
what may be detected due to abnormalities in capnography
airway obstruction
146
what is produced by cells of body during metabolism into circulatory system and then is diffused into lungs
CO2
147
what is a better indicator of rosc during resuscitation
exhaled CO2
148
what cardiac changes can etco2 aid in detecting
decreased cardiac output,
pulmonary embolism,
reduced blood flow to lungs
149
what guides ventilator changes and can give a trend of anesthesia depth
CO2
150
what could a sudden increase in co2 represent during code
spontaneous cardiac function/output
151
what is difference between etco2 on monitor and blood
blood is usually 5 higher than monitor
152
What are some complications that can happen that etco2 can help alert to
esophageal intubation,
apnea,
extubation,
disconnection,
ventilator malfunction,
ett partial obstruction,
compliance vs resistance changes,
spontaneous resp w/muscle relaxant use,
poor lma fit,
leaking ett cuff
153
what is phase 1 in capnography (A)
inspiratory baseline- 0- low valley
154
what could be a problem if your co2 isn't reading 0 during phase 1
co2 canister needs to be changed out
155
what is phase 2 in capnography and what letters are in it
initiating exhale- b- c
156
what is phase 3 in capnography and what letters are in it
plateau c-d
no plateau= not reading correctly
157
how is slope of phase 3 increased
kink, ventilation perfusion status,
158
what is phase iv in capnography and what letters are in it
end tidal point down to zero (inhalation)
d-e
159
what is the letter with the highest co2 number on capnography
d- 35-40 torr
160
what could cause no co2 in gas line
obstruction,
disconnection,
esophageal intubation,
no blood circulation to lungs
161
what uses each anesthetic gas's ability to absorb specific frequencies of emr in the infrared spectrum
infrared absorption analysis
162
what anesthesia gas monitoring has advantages of being fast, reliable, low cost, multiagent/multigas
mass spectrometry
163
what anesthesia gas monitoring has disadvantages of warm up time, space, must be scavenged, and measures only preprogrammed gases
mass spectrometry
164
what has a laser that interacts with gas molecule and measures the fraction of energy absorbed at different live wavelengths called scattering
raman spectrometry
165
what anesthesia gas monitoring is less accurate with pediatric cases, since they use high carrier gas flow rates and small tidal volumes
raman spectrometry
166
what are disadvantages of raman spectrometry
costly, less accurate in pediatrics
167
what are advantages of raman spectrometry
no scavenging,
accurate,
fast multi-gas/agent
168
what do you need to do with o2 flow sensor (galvanic cell)
calibrate to room air, degrade in 30 days
169
what does vaporizer output assess
detects incorrect agents
detect vaporizer turned off/empty
provides info on uptake and elim of agent in pt
170
what should baseline be on capnography
zero
171
what can interfere with bis
shivering, electrocautery, forced air warmer, cardiac pacemaker spikes
172
how does electrocautery interupt bis
unipolar cautery overloads bis signal transmission
173
how can you reduce exposure to unheated gases and aid in volatile agent sparing
low FGF
174
t or f- the icu ventilator breathing circuit is typically a closed system
f- typically open system, does not have gas recirculated through
175
t or f- modern anesthesia machines are typically closed system
f- semi closed systems
176
why are modern anesthesia machines considered semi closed systems
removal of co2
conservation of volatile agents
177
what are the two major functions of the lung
ventilation
oxygenation
178
what is the term for elimination of co2
ventilation
179
what is the term for intake of oxygen
oxygenation
180
what determines the partial pressure of co2 in the arterialized blood
alveolar ventilation
181
what is the best indicator for oxygenation
PaO2
182
t or f- PAco2 is best estimated from Paco2
TRUE
183
the quantity of ___________ ________________ produced normally dictates minute ventilation
carbon dioxide
184
normally dead space minute ventilation makes up _______ of the minute volume
1/3
185
what is the normal oxygen consumption of an average 70kg adult human
250 ml/min
186
what is the ratio between co2 production and oxygen consumption
respiratory quotient
187
what is normal respiratory quotient
200/250
188
what is the energy expended to move the gas into and out of the lungs
work of breathing
189
work of breathing is measured by the work needed to overcome what two things
elastic properties of lung/chest wall
resistance aspects of circuit
190
what parts of circuit provide resistance
et tube
large and small airways
191
what does change of airway pressure/change in volume
elastance
192
under normal circumstances, the work of breathing is mostly overcoming what:
elastance of lung and chest wall
193
t or f- mechanical ventilation exhalation is passive
true
194
what is the formula for compliance
change in volume/change in pressure
195
what two pressures must the ventilator overcome during inspiration
compliance and resistance
196
changes in inspiratory pressure result in changes in what two variables
tidal volume
inspiratory flow
197
what does the symbol PI stand for
inspired pressure
198
what does the symbol PIMAX stand for
peak inspiratory pressure
199
what does the symbol VT stand for
tidal volume
200
what does the symbol mv mean
minute volume
201
what does the symbol QI stand for
inspiratory flow
202
what does the symbol f stand for
frequency
203
what does the symbol TC stand for
resp cycle time
204
what does the symbol Tplat stand for
inspiratory pause time
205
what does the symbol TI stand for
inspiratory time
206
what does the symbol TE stand for
expiratory time
207
what does the symbol I:E stand for
inspiratory/expiratory ratio
208
t or f- inspiratory pause (tplat) is not a part of the inspiratory time
false
209
what determines the duration of the respiratory cycle
frequency
210
in the I:E ratio, which is generally the bigger number
expiratory- need more time to exhale
211
what does intermittent positive pressure ventilation or PEEP do to cardiac output and how
decreases- pressure increases intrathoracic pressure, which decreases blood flow to heart, which decreases cardiac output
212
when does intrathoracic pressure increase during IPPV vs PEEP
IPPV: inspiration
PEEP: expiration
213
what are two possible negative effects of peep
increased dead space
reduced cardiac output
214
why is someone with pneumonia or ards at an increased risk for further lung damage
the good lung segments receive more tidal volume and peep, which can cause further damage
215
t or f- maintain large tidal volume (15-20ml/kg) to maintain alveolar distention and prevent atelectasis
f- may cause barotrauma
216
what can overdistention of health alveoli cause
pulmonary interstitial emphysema
pneumothorax
217
what is the recommended tidal volume
6-8 ml/kg
218
peep maximizes what lung volume measurement
functional residual capacity
219
what kind of ventilation is the goal to increase mean airway pressure and minimize peak pressure
inverse ratio ventilation
220
what kind of ventilation seeks to recruit alveoli without overdistention
inverse ratio ventilation
221
which bellows rises during exhalation
ascending- standing
222
which bellows falls during exhalation
descending- hanging
223
which type of bellows may inflate with room air even during circuit disconnect or leak
descending- hanging
224
what can a hole in a bellows lead to
barotrauma
225
does bellows driven or piston driven ventilator have more accurate tidal volumes
piston drive
226
which type of ventilator relies on a spinning fan to produce a drive gas pressure
turbine
227
t or f- exhalation is typically a passive event
true
228
how do you manipulate exhalation pressures
peep
229
what can high pressure ventilation lead to with blood pressure
hypotension
230
t or f- extending an inspiratory plateau may improve gas exchange by keeping alveoli expanded for a longer period
true
231
when is the relief valve to the scavenging system sealed
during inspiration
beginning of exhalation
232
t or f- relief valve to scavenging system is closed during the beginning of exhalation until the ascending bellows has been refilled
true
233
what provides the constant 2-3 cm h2o of peep even when peep hasn't been manually turned on
relief valve
234
t or f- there is alway 2-3 of peep on ventilator even when peep hasn't been manually turned on
true
235
why is it important to check adjustable relief valve on machines that have it
if it is improperly adjusted, it can result in too high of peep which can cause barotrauma or hypotension
236
what are the 3 ventilator modes of breathing
controlled breathing
assisted/supported
spontaneous
237
t or f- in controlled breathing mode, the patient can contribute effort toward work of breathing
f- cannot contribute any
238
what is set parameter in volume control ventialtion
volume
239
when needs to be closely monitored during volume control ventilation
Peak airway pressure- because airway pressure can get really high to hit specified volume in those with poor lung compliance
240
what is fixed parameter in pressure control ventilation
pressure
241
when are high flows delivered during pressure control ventilation
start of inspiration
242
what should be monitored with pressure control ventilation
CO2
tidal volume
243
which ventilator setting is the patient's effort to breath manifested by negative deflection in airway pressure, and a predetermined negative pressure triggers the vent to deliver a set tidal volume
assisted ventilation
244
which vent setting will a control breath not be delivered as long as the patient triggers ventilator more than the interval defined by set control rate
assist control ventilation
245
what are the characteristics of acv
-set control rate: patient triggers ventilator, but if less than interval defined, vent initiates breath
-volume is also set on machine
246
what is set by clinician in pressure support ventilation
peak airway pressure,
i time,
trigger
247
which mode does clinician set mandatory vent breaths by either volume or pressure at a defined rate and i time
intermittent mandatory ventilation
248
what is patient at risk for with intermittent mandatory ventilation
breath stacking-->barotrauma
249
t or f- breath stacking is a common problem with SIMV mode
false
rarely occurs
250
what does the cpap number represent on vent
airway pressure between exhalation and inhalation
251
the gas flow in the airway is always __ between exhalation and inhalation
0
252
which mode has t-slope, simv or psv pro
psv pro
253
what should you make sure to monitor with pressure control ventilation
CO2
tidal volume
254
if lung perfusion/cardiac output decreases, what will happen to amount of dead space ventilation
increases
254
what modes are commonly used with lma
SIMV
pressure support
255
how is incoming gas warmed in the bain circuit
exhaled gas
256
which mapleson is best for spontaneous ventilation
mapleson a
worst= B
257
which mapleson is best for controlled ventilation
d
worst= A
258
what is an example of a surgery where patient will have decreased compliance
laparoscopy
259
what is the maximum amount of additional air that can be inspired from the end of normal inspiration
inspiratory reserve volume
260
which volume keeps alveoli open during exhalation
residual volume
261
what is the maximum volume of additional air that can be expired from end of normal expiration
expiratory reserve volume
262
what is the volume of air remaining in lung after a maximal expiration
residual volume
263
what is fev1
forced expiratory volume in 1 sec
264
t or f- you can breath all of the air out in your lungs
false
always a residual volume
265
what is the only lung volume that cannot be measured with a spirometer
residual volume
266
what is the volume of air contained in lungs at end of maximal inspiration
total lung capacity
267
what is the term for the sum of the 4 basic lung volumes
total lung capacity
268
what is the equation for tlc
residual volume + inspiratory reserve volume+ tidal volume + expiratory reserve volume
269
what is vital capacity
max volume of air that can be forcefully expelled from lungs following a maximal inspiration
270
what are the two formulas for vital capacity
tlc- residual volume
or
inspiratory reserve+tidal volume+ expiratory reserve
271
what is functional residual capacity
amount of air left in lung at end of normal expiration
272
residual volume + expiratory volume
functional residual capacity
273
what is the reservoir that prevents hypoxemia during apnea
functional residual capacity
274
what is approximate normal frc
35 ml/kg
275
what are some factors that decrease functional residual capacity
general/inadequate anesthesia
obesity
pregnancy
neonates
certain positions
paralysis
excess iv lfuids
high fio2
reduce pulm compliance
276
which positions decrease frc
supine
lithotomy
trendelenburg
277
what are some factors that increase functional residual capacity
advanced age
certain positions
obstructive lung disease
peep
sigh breaths
278
which positions increase frc
prone
sitting
lateral
279
how does position increase or decrease frc
changes position of diaphragm
gravity alters distribution of pulmonary blood flow
280
how does advanced age increase frc
decreased elastic lung tissue= air trapping= increased residual volume
281
why do neonates have decreased frc
less alveoli= less lung compliance
ribcage is cartilaginous, prone to collapse
282
why does pregnancy decrease frc
-diaphragm shifts cephalad as a result of uterus
-restrictive lung disease
283
why does obesity decrease frc
decrease chest wall compliance
increased airway collapsibility
284
how does general anesthesia cause decreased frc
diaphragm shifts 4cm cephalad as a result of decreased inspiratory muscle tone and increased expiratory muscle tone
285
how does sigh breaths increase frc
recruits collapsed alveoli
286
how does obstructive lung disease increase frc
air trapping= increased residual volume= increased frc
287
how does high fio2 decrease frc
absorption atelectasis= conversion of low v/q unit= shunt unit
288
how does peep increase frc
prevents alveoli from collapsing
partially overcomes general anesthesia effects
decreases venous blood admixture= increased pao2
289
t or f- peep pops open alveoli aka alveolar recruitment
f- maintains open alveoli from collapsing
290
how do you pop open more alveoli
alveolar recruitment mechanism
-forceful breath for long period=high peak
291
how does excessive iv fluids decrease frc
fluid accumulation in dependent lung favors zone 3
292
how does inadequate anesthesia decrease frc
straining= forceful expiration= decreased lung volumes
293
how does paralysis decrease frc
diaphgram moves cephalad= decreased lung volumes
294
what are some disease that decreases frc/pulmonary compliance
acute lung injury
pulmonary edema
pulmonary fibrosis
atelectasis
pleural effusion
295
what conditions cause diaphragm to shift cephalad causing decreased frc
general anesthesia
pregnancy
paralysis
296
what lung capacity is of less clinical significance
inspiratory capacity
297
what is the max volume of air that can be inspired from normal-end expiratory position
inspiratory capacity
298
what is the formula for inspiratory capacity
tidal volume + inspiratory reserve
299
what are the names of the 4 lung zones
1. collapse
2. waterfall
3. distention
4. interstitial pressure
300
which lung zone is only present with pathology
1 and 4
301
which lung zone is pulmonary artery pressure negligible
zone 1
302
after blood passes through alveoli of zone 2, where does it go
falls into pulmonary venous system
303
what is blood flow proportional to in zone 2
Pa-PA
304
what is blood flow proportional to in zone 3
Pa-pv
305
pressure is reflected from ____________ ventricle back through zone ____ to site where swan is wedged
left, 3
306
what is blood flow proportional to in zone 4
Pa-Pi
307
which zone is present with pulmonary edema
zone 4
308
what is normal alveolar ventilation (V)
4L/min
309
what is normal capillary perfusion (q)
5L/min
310
what is normal vq range
0.3-3.0
311
what are the 4 components of a mapleson circuits
breathing tube
fresh gas inlet
apl valve
reservoir
312
which mapleson is considered a bain circuit
mapleson d
313
what are the advantages and disadvantages to bain circuit
advantages: fgf flows through center, helps prevent heat loss
disadvantages: fgf may be kinked without you knowing it
314
which mapleson is a jackson rees circuit
mapleson f
315
which mapleson is used for peds laryngospasm
mapleson f- jackson rees
316
what is decreased in circle system
dead space
317
what breathing test is severe copd defined by
fev1 <30% predicted
318
what is vq of an absolute intrapulmonary shunt
vq is 0
319
what is vq of a relative intrapulmonary shunt
low v/q ratio
320
what is a shunt
airway obstruction to area= low v/q
-low oxygenated blood leaving alveoli
321
what is a shunt
airway obstruction to area= low v/q
-low oxygenated blood leaving alveoli
322
what is deadspace
blood flow problem- high v/q ratio
high oxygen, but no blood flow
323
what can be a cause of deadspace
PE
324
what mismatch does dead space cause
high v/q
325
what mismatch does shunt cause
low v/q
326
what is predominant effect of low v/q
hypoxia (shunt)
327
what is predominant effect of high v/q
hypercapnia (dead space)
-also hypoxia
328
which v/q is perfusion to nearby segment of alveoli increase and ventilation to diseased segment is wasted
high v/q
329
which v/q is ventilation increased to nearby segments--hypoxic vasoconstriction
low v/q (shunt)
330
which v/q ratio will you have hypoxic vasoconstriction
low v/q ratio- shunt
331
what is v/q defect when v/q values is 0.8
normal
332
what is v/q defect when v/q value is 0
airway obstruction - shunt
333
what is v/q defect when v/q value is infinity
pulmonary embolus- dead space
334
what is v/q defect when pAo2 is 150 mmhg
pulmonary embolus-dead space
335
what is v/q defect when pAco2 is 0
pulmonary embolus- dead space
336
what is v/q defect when pao2 is 40
airway obstruction- shunt
337
what is v/q defect when paco2 is 46 mmhg
airway obstruction- shunt
338
what are normal values of pa/pA o2/co2
pAo2= 100
pAco2= 40mmhg
pa02- 100mmhg
paco2= 40 mmhg
339
any process that decreases ______________ ______________ and ____________ ________________ will lead to a relative increase in dead space ventilation
cardiac output
lung perfusion
340
what are some causes of decreased cardiac output and lung perfusion leading to increased dead space
hypovolemia
shock
pulmonary embolism
reverse trendelenburg
increased intraabdominal pressure
341
where is dead space in circle system
distal to y piece
342
what are causes of resistance in circle system
valves and absorbers
343
when a patient is in lateral position, which side gets more air
independent
344
what is the independent zone of lung in lateral position
zone1
345
when a patient is in lateral position, which side gets more blood
dependent
346
what provides heat/moisture in circle system
granules
347
what decreases moisture in circle system
high flow
348
how do you adjust i:e ratio for copd
lengthen e time so they have longer to get air out
349
how long will each breath take if freq is set to 12
5 sec
350
if I:E ratio is 1:1, how long will inspiration take if freq is set to 12
2.5 seconds
351
what can high volumes cause in ards or acute copd exacerbation cause
barotrauma
352
t or f- co2 absorber prevents rebreathing of co2 in closed system
true
353
what does fgf need to be below to make it a closed system
<1 L/min
354
at what fgf do you not need co2 absorber
> 5L/min
355
during inspiration gas flow into alveoli until what?
until alveolar pressure reaches upper airway pressure
356
t or f- during expiration, positive pressure is removed
t- it decreases
357
what is the process of providing positive airway pressure at upper airway
mechanical ventilation
358
why is the lung elastic
elastic and collagen fibers in parenchyma
359
what is the formula for elastance
Change in pressure (cmH20) / change in volume (L).
360
what is the opposite of elastance
compliance
361
what do lungs with low compliance need to infalte
more pressure
362
what is the equation for compliance
change in volume (L)/
change in pressure (cmH2O)
363
what are the two types of lung resistance
tissue resistance
airway resistance
364
tissue resistance accounts for ___ of total resistance
20%
365
what kind of resistance is impedance to motion caused by moving organs and chest wall during resp cycle
tissue resistance
366
what does resistance depend on
type of flow- turbulent/laminar
geometry of tube
viscosity of gas
flow rate of gas
367
what is formula for resistance derived from by
poiseuilles law
368
how is resistance calculated via poiseuilles law
r= 8NL/pi (r^4)
369
what is amount of tidal volume that a patient receives
volume
370
what is the term for measure of impedance to gas flow rate
impedence
371
what is the measure of rate at which gas is delivered
flow
372
what setting refers to number of breathers per minute that the ventilator delivers
frequency
373
what is typical freq
8-12 bpm
374
t or f- ventilator always provides all of patient's ventilation
f- can also breath spontaneously between vent breaths
375
how do you calculate tidal volume
6-8 ml/kg ideal body weight
376
what disease may require lower tidal volume
ards
acute copd exacerbation
asthma
377
what patient may benefit from higher tidal volumes that prevent atelectasis
neuromuscular disease
378
what is highest level of pressure applied to lungs during inhalation
pip (cmh2o)
379
what should pip never be higher than
40 cm h2o
unless patient has ards
380
what should pip be limited to in masked/LMA patient
20 cm h2o
381
what causes ventilator to cycle to inspiration
trigger
-time, pressure, volume, flow
382
what kind of trigger does vent cycle at a frequency as determined by controlled rate
time trigger
383
what kind of trigger does vent sense patient's inspiratory effort by way of a decrease in baseline pressure
pressure trigger
384
what is trigger in most modern vents
flow trigger
385
how does flow trigger work
deliver constant flow around circuit through resp cycle, deflection in this flow by patient inspiration is monitored by vent and it delivers a breath
386
which requires less work by patient, pressure or flow trigger
flow trigger
387
what can be used to increase oxygenation by maintaining alveoli
peep
388
what is peep most patients are started on
5 cm h2o
389
who requires higher level of peep
stiff lungs- ards
390
what does peep help prevent with ards
intrapulmonar shunting
391
what should peep not exceed
20 cm h2o
392
what does high peep settings increase risk of
subq emphysema
pneumothorax
393
how is t slope measured
seconds
394
what controls how long it takes to reach set pressure
t slope (sec)
395
what is range of t slope
0-2 seconds
396
what mode is t slope most important in
pressure support modes
397
what t slope is set longer than inspiratory time, what can happen to tidal volume
shortened tidal volume
398
what does a higher t slope mean for the slope
more gradual slope
399
how do calculate delta p
PIP-PEEP
400
during pressure limited ventilation the delivered tidal volume is determined by the pressure level above ____________
peep
401
what type of ventilation is not optimal for poorly compliant lungs
volume control
402
what does ventilator determine in volume control
pressure required
403
what are advantages of volume control
guaranteed minute vent
more comfortable for patient-if-not-spontaneously-breathing
404
what type of ventilation is more comfortable for patient if they are not spontaneously breathing
volume control
405
is volume control a controlled mechanical ventilation mode or an assisted mechanical ventilation
controlled
406
what is typical fio2 during a case
40-50%
407
what typical fio2 during extubation
50-80%
408
what type of ventilation has guaranteed minute ventilation
volume control
409
what are presets on volume ventilation
volume
peep
rate
i time
fio2
410
what type of ventilation does vent determine tidal volume
pressure control
411
what type of ventilation is minute ventilation not guaranteed
pressure control
412
what type of ventilation provides more support at lower pip for poorly compliant lungs
pressure ventilation
413
what are presets of pressure ventilation
pip
peep
rate
i time
fio2
414
in pressure control what changes according to lung compliance
tidal volume
415
in volume control, what varies based on pulmonary compliance/airway resistance
delivered peak inspiratory pressure
416
what happens when patient is spontaneously breathing during pressure control
pip is fixed, mode reduces discomfort
417
which ventilation method is better for spontaneously breathing patient, volume or pressure
pressure
volume control will give asynchronous breaths
418
what happens when patient is spontaneously breathing during volume control
pip is variable, delivers breath during asynchrony leading to increased work of breathing and discomfort
419
what mode can cause asynchrony during spontaneous breathing
volume control
420
how many breaths does pressure support give
none
421
what parameters are set during pressure support
pressure support
fio2
422
what is purpose of pressure support
final step prior to extubation
assist spontaneous breath
423
what is final mode before extubation
pressure support
424
what mode are patient's spontaneous breaths supported by a set pressure
pressure support
425
what does simv mode stand for
Synchronized Intermittent Mandatory Ventilation
426
what is simv mode
mandatory breaths-synchronized
pressure support for spontaneous breaths
427
will inspiratory and expiratory flow on copd flow volume loop be low or high
low
428
which flow volume loop has low residual volume
restrictive flow volume floop
429
which flow volume loop is inspiratory volume diminished
restrictive flow volume
430
what is your ventilator mode if you set your freq at 12 but the patient can still initiate spontaneous breaths where vent provides pressure supoort
simv
431
what is psv-pro mode
pressure support with a backup rate
432
what are differences between psv-pro-and simv
psv has: t slope, ps with backup rate
433
what is diminished on copd flow volume loop
expiratory flow
434
why is expiratory flow loop diminished in copd
resistance due to airway collapse
435
which flow volume loop has normal amount of volume exhaled in three seconds, but forced exp volume in one second is low
copd
436
t or f- residual volume is high in copd
true
437
are inspiratory/expiratory flow low or high in copd
low
438
residual volume is low in the ________________ flow volume loop
restrictive
439
what happens to inspiratory volume in restrictive flow loop
diminished
440
t or f- peak expiratory flow and one second expiratory flow is normal copd flow loop
f- restrictive flow volume loop
441
what are examples of variable extrathoracic obstruction
paralysis of vocal cords
laryngospasm
thyromegaly
tracheomalacia
442
which obstruction is indicative of upper airway obstruction- extrathoracic or intrathoracic
extrathoracic
443
what does flow volume loop of extra-thoracic obstruction indicate
upper airway obstruction
444
t or f- extrathoracic obstructions have normal inspiration but abnormal exhalation
f- abnormal inspiration, normal exhalation
445
which obstruction does inspiratory plateau reach a low value-extrathoracic or intrathoracic
extrathoracic
446
what kind-of-obstruction does inspiratory plateau reach a low value
variable extrathoracic obstruction
447
what would cause a fixed intrathoracic obstruction flow volume loop
fixed large airway obstruction
tracheal stenosis
foreign body/neoplasm
448
what obstruction effects both inspiration and expiration-extrathoracic or intrathoracic
fixed intrathoracic obstruction
449
what's the difference between variable extrathoracic vs variable intrathoracic obstruction
extra: inspiration obstruction
intra: expiration obstruction
fixed-intra: effects both
450
what is A
liters
451
what is B
L/sec
452
what is C
expiration
453
what is D
inspiration
454
what is E
obstruction
455
what is F
normal
456
what is G
restrictive
457
what is H
fixed
458
what is A (x axis)
volume
459
what is B
vital capacity
460
what is C (y axis)
flow
461
what is D
peak expiratory flow rate
462
what is E
normal
463
what is G
obstruction
464
what is A
Vt
465
what is B
expiration
466
what is C
L/sec
467
what is D
total lung capacity
468
what is E
residual volume
469
what is F
functional residual capacity
470
what is G
vital capacity
471
what circuit is this
mapleson A
472
what circuit is this
mapleson D
473
what circuit is this
mapleson B
474
what circuit is this
mapleson E
ayres piece
475
what circuit is this
mapleson C
476
what circuit is this
mapleson F
jackson-Rees
477
which is the only circuit where the fresh gas inlet is near the bag
mapleson A
478
which is the only circuit with no corrugated tubing
Mapleson C
479
which is the only circuit with the APL valve away from the patient
Mapleson D
480
which is the only circuit without a reservoir bag
Mapleson E
481
which circuit does not have an APL valve anywhere
Mapleson E
482
which circuit can have either an APL valve or a small hole at the tail of the bag that is manipulated to control pressure like an APL valve
Mapleson F
483
which circuit is best for a spontaneous ventilation patient
Mapleson A
A>DFE>CB
484
which circuit is the worst for spontaneous ventilation patient
Mapleson B
485
which circuit is best for the controlled ventilation patient
Mapleson D
DFE>BC>A
486
which circuit is the worst for controlled ventilation patients
Mapleson A
487
acronym for best circuits for spontaneous ventilation patients
All Dogs Bite
A>DEF>CB
488
acronym for circuits for controlled ventilation patients
DFE>BC>A
Dont Be Arrogant
489
which system is a modified Mapleson D design
Bain system
490
what is the Pethick test
used to test circuit integrity during pre-anesthetic checkout procedure
491
what does this show
esophageal intubation
492
what does this show
incompetent expiratory valve
incompetent inspiratory valve
exhausted soda lime canister
493
what does this show
prolonged upstroke and expiratory plateau
494
what does this show
incompetent inspiratory valve
-not returning to zero axis
-inspiratory limb prolonged
495
what is this
hyperventilation
-less amplitude
-ventilation is increased
496
what does this show
hypoventilation: rate
-y axis scale large
-slow down in RR
-probably chronic condition
497
what does this show
inspiratory effort
-lack of adequate paralysis
-alveolar plateau is key
498
what does this show
cardiogenic oscillations
499
what does this show
external chest compressions
500
what does this show
incompetent inspiratory valve take off angle
501
what is this
malignant hyperthermia
-very rapid increase in CO2
502
what does this show
hypoventilation
-wave does not reflect hypercarbia
-acute hypoventilation
503
what does this show
pulmonary embolus2 is down (low)
-alveolar plateau is angled
rate is increased
