Transcript Review for Final Exam in RSPT 2160

Review for Final Exam in
RSPT 2160
By Elizabeth Kelley Buzbee AAS,
RRT-NPS, RCP
Question
• Your intubated patient is being bagged at
100% and you see that the Sp02 on her
finger is reading 93%.
• You would best set up the mechanical
ventilator at what Fi02?
answer
• If the Sp02 is only 93% on Fi02 100%, we
know that the P[A-a]D02 is wide.
• We don’t have enough information, so stay
at 100% on the mechanical ventilator until
we can get an ABG.
• Even with an ABG, we really don’t like to
make massive changes-it is safer to
decrease in steps of about 10-20% at a
time [Egan’s pp.1039, Box 41-18]
question
• While the anesthesiologist is bagging a
patient with no history of lung disease, you
need to set up initial ventilatory settings.
• If this female patient is 5 feet 3 inch tall,
what is her IBW and what would be a
reasonable VT?
answer
100 # for 5 feet +[3 x 5] = 115 # IBW
115/2.2 to convert to kg = 115/2.2 =52 kg.
At 10-12 mL/kg [Egan’s pp.1009]
We could safely start her
at a VT of 520-624 ml
Question
• While the anesthesiologist is bagging an
adult patient with no history of lung
disease, you need to set up initial
ventilatory settings.
• At what mode and respiratory rate
would start this patient?
answer
• CMC or SIMV are both acceptable modes
to start patients with most disorders.
• A respiratory rate of 10-12 bpm is
reasonable place to start with a person
with healthy lungs [Egan’s pp.1009]
question
• Your patient has no history of refractory
hypoxemia, yet the doctor orders a PEEP
of 3 cmH20.
• Why is this not a problem.
answer
• PEEP of less than 5 are considered
physiological PEEP-- similar to that level
of PEEP created in the lower airways by
the actions of the vocal cords during
breathing.
Question
• While the anesthesiologist is bagging an
adult patient with no history of lung
disease, you need to set up initial
ventilatory settings.
• At what initial flow rate do you want to
start with this patient; what flow curve
would you pick?
answer
• This person could be started at a flow rate of 6080 lpm to get a I:E ratio of 1:2 or more. [Egan’s
pp.1009]
• We want an inspiratory time of about 1 second
for an adult [Egan’s pp.1033]
• The initial flow curve for most folks could start
with square wave or a descending ramp, with
adjustments based on problems such as
excessive PIP or I:E problems [Egan’s pp.1033]
question
• You would look at a pressure-volume loop
to determine what kind of problems with a
patient who is getting volume-targeted
ventilation? [CMV or A/C]
answer
• The pressure-volume loop is used to assess
compliance. [Pilbeam pp. 197]
• pressure-volume loop can be used to look at
RAW [Pilbeam pp. 195]
• As flow rates change, the pressure-volume loop
can be affected. [Pilbeam pp. 195]
• pressure-volume loop can be related to WOB,
and to failure to trigger due to sensitivity issues
[Pilbeam pp. 198]
• The pressure volume loop can show you that
the Vt is excessive as we see pressures rise
without changes in volume
question
• Describe the use of monitoring of the
pressure curves during volume targeted
ventilation.
answer
• Other than giving information about PIP,
looking at the pressure vrs time curve,
– identify inspiratory holds [Pplateau]
– watch the base line rise as PEEP is dialed in.
– see the effect of gross changes in flow rate
which could alter inspiratory time and/or PIP
question
• How long do you need to wait before you
get an ABG on a patient who has had
ventilatory parameter changes?
answer
• As a rule, we need to get ABG within 30-1
hour of ventilator parameter changes so
that there is time for the patient to
stabilize.
question
• Your patient [70 kg] has
the following ABG on
these settings.
•
•
•
•
CMV rate 12
Vt 700 cc
PEEP 3
Fi02 40%
You would recommend
what parameter
change?
pH
PaC02
HC03-
Pa02
7.38
45
26
48
answer
• The pH and the PaC02 both show that the
ventilation is adequate, however the
patient has moderate hypoxemia at Fi02
40%
• increasing the Fi02 to 66% will raise the
Pa02 but we risk 02-toxicity, so a better
choice might be to raise the PEEP by 1-2
cmH20
question
• Your patient [70 kg]
has the following ABG
on these settings.
• CMV rate 12
• Vt 550
• PEEP 3
• Fi02 30%
You would recommend
what parameter
change?
pH
PaC02
HC03-
Pa02
7.275
49
22
70
answer
• increase to VT 700 ml [10ml/kg]. this will
drop the PaC02 and raise the pH.
• The Pa02 of 70 torr is adequate and there
is a chance that with increased alveolar
ventilation associated with the volume
change that this patient’s Pa02 might rise
also
question
• Your patient [68 kg] has
the following ABG on
these settings.
•
•
•
•
CMV rate 10
Vt 750
PEEP 5
Fi02 65%
You would recommend
what parameter
change?
pH
PaC02
HC03-
Pa02
7.40
38
23
135
answer
• The ventilation is fine; keep VE the same
• but we have excessive oxygenation, so we
need to decrease the Fi02 from 65% to
40% to get the Pa02 back to WNL.
question
• Your patient’s mechanical ventilation is on
the following settings:
SIMV 12
VT 700
Fi02 35%
PEEP 0
What parameter alarms need to be set?
answer
• We need to set the VE high and low alarms [+/10% Pilbeam pp. 132] [+/- 20% Egan’s]
• We need to set the low Pressure [5-10 below]
and high pressure [10-20 above] alarms
• We need to set the Fi02 low and high alarms [+/5%]
• We need to set the return VT about 100 ml low,
Pilbeam says 10%
• Low PEEP alarms 2-5 [Pilbeam pp. 132]
Question
• Your patient has a cuffed endotracheal
tube and you need to measure it.
• At what part of the ventilatory cycle should
this parameter be measured?
answer
• We measure the cuff pressure at end
inspiration because the increased airway
pressure will increase the pressure inside
the cuff –so this is the point where the
pressure is going to be its highest
question
• What is the effect of a endotracheal tube’s
cuff pressure of more than 24 cmH20?
answer
• Cuff pressures in excess of 25 mmHg can
hamper the capillary blood flow in the
trachea so that the tracheal tissue can
suffer damage from decreased perfusion
Question
• Identify those parameters you would
measure and calculate to discover that a
patient has suffered some form of airway
occlusion?
answer
• If there is serious occlusion of the artificial
airway, on the ventilator, we would see the
following:
– Increased PIP with the same Pplateau
– Increased RAW [see above]
– Decreased return VT & VE especially if the
high pressure alarm is functional
Question
• List the parameters, waveforms and other
indicators that an entubed ventilated
patient has increased WOB due to
bronchospasm.
answer
• Increased resistance to flow would show
up:
– on the flow/volume loop
– Flow curve- signs of air trapping
– Volume flow curve
– the PIP would rise without Pplateau
– The RAW would rise
Question
• How would you handle serious cardiac
arrhythmias triggered by suctioning?
answer
• I would stop suctioning, get the catheter
out of the airway and increase the Fi02
100% till the EKG returned to normal
• I would watch the Sp02 and the patient’s
WOB, LOC and bilateral BBS.
• In the future, I would raise the Fi02 for
several minutes prior to suctioning and I
would watch the level of and the timing of
the actual suctioning.
question
At 10:00 AM your patient is
on mechanical ventilation
on the following settings:
• CMV 12/ total f 12
• VE 7.5
• VT 700 [10ml/Kg IBW]
• PIP 33
• Pplateau 31
• PEEP 6
• Fi02 60%
The doctor wants to ‘get this
patient off the ventilator this
afternoon.” Is this possible?
pH
PaC02
HC03-
Pa02
7.40
38
23
108
answer
• Before we can wean this patient we need to assess the
spontaneous parameters, we need to check the history for a
resolution of the original problem, we need to assess the level of
sedation/paralytic agents.
– This patient seems too comfortable on the current settings- no
spontaneous breathing. Maybe we can change the mode to SIMV and
decrease the rate to 10 bpm to increase ventilatory demand
• Also his Fi02 needs to be less than 50% - we could wean to 45%
to get a predicted Pa02 80 torr
• But his C static is only 28 ml/cmH20 which implies that his WOB
would be too high for him to attempt to breath without help. We
could put him on SIMV 10 with PS of 10 -12 and watch his total RR.
If it rises more than 20%, we need to increase the PS.
• In short, we can start to wean this afternoon, but we may not get this
patient off the ventilator that quickly.
Question
• If you had a EKG and on lead II you
noticed that there are more P waves than
QRS waves, what kinds of arrhythmias are
we looking at?
Question
• We have [1] extra P waves such as PAC
or A-fib, [2] or we have a complete AV
block in which the atria and the ventricle
are pacing in isolation from one another.
Usually the atria will be faster in this case.
question
• Your patient has no pulse and the EKG is
completely chaotic and you cannot
recognize anything.
• What is going on and what do you do?
answer
• Course V-fibrillation
• We need to start CPR and get patient on a
defibrillator or AED
question
• When you initially set up a ventilator and
forget to increase the Pressure limit to a
reasonable level for this patient, what
would tell you that you have made a
mistake?
answer
• The audible and visual high pressure alarm will
sound
• If you are in volume-targeted or in pressuretargeted ventilator modes, the breath will end
prematurely, so that the return VT is lower than it
should be.
• The inspiratory time might be shortened.
• Remember, if you had scanned the settings
before placing this on the patient you would
have caught this mistake.
question
• You are setting up a Servo 900 C and to
set a Vt of 550 and a rate of 10 on A/C,
you would set the preset VE at what level
and the CMV at what level?
answer
• In volume control mode, we would set the
VE [.550 x 10] at 5.5 LPM.
• The CMV is set at 10 bpm
question
• You are still setting up the Servo 900 C.
after selecting the preset VE at 5.5 LPM
and the CMV at 10 bpm, you want to
select a I:E of 1:3….
• so what Ti % do you select and after you
select it ,calculate the peak flow [flow rate.]
answer
• At 1:3 this is 25:75 or 25%
• The flow rate is preset VE / Ti% or
[5.5 LPM / .25] = 22 LPM
question
• If your ventilator starts alarming and you
cannot figure out what is going on, what
do you do?
answer
• Remove the patient from the ventilator and
bag while you assess the patient’s VS,
BBS & Sp02
• If the patient is alert and anxious, reassure
him both verbally and with synchronized
bagging with his efforts
• Once the patient is stabilized, ask the
nurse or another RCP to bag while you
trouble-shoot the ventilator & circuit.
question
• Define the term “control variable.”
answer
• A control variable is the variable that
determines the inspiration of a ventilator in
a given mode. [Pillbeam pp. 417]
question
• Identify the function of measuring a
ventilated patient’s RAW.
answer
• A function of measuring the patient’s RAW
is to assess him for an explanation for
respiratory distress.
• If the RAW is increased, you need to
assess him for bronchospasm, need for
suctioning, or a endotracheal tube that is
too small for the VE and the flow rates
• To be complete, you might want to add
measuring the Cstatic for a possible change
in compliance.
question
• What would be the function of measuring
the NIF of a patient who is on mechanical
ventilation?
answer
• Measuring the patient’s NIP is part of the
assessment of a patient’s ability to take a
deep breath because this measures
strength of the chest wall muscles
question
• Calculate the P[A-a]02 when the Pb is
550, the Fi02 is .21 , PaC02 is 45 torr &
the Pa02 is 40 torr.
answer
PA02 = (PB – PH20) x Fi02 – [Ca02/.8]
PA02 = (550 – 47) x .21 – [45/.8]
PA02 = 105.63 – 56.25
PA02 = 49.38
P(A-a)02 = PA02- Pa02 =
• P(A-a)02 = 49.38 - 40 = 9.38 torr
question
• Your intubated patient
has the following
parameters:
mode
VT
PIP
P
plateau
CMV
800
35
26
PEEP
flow rate
5
60 lpm
3 hours ago, his lung compliance was 55 ml/cwp
Is his lung compliance getting better or worse?
answer
• We need to check the C
static to assess his lung
compliance. If we assume
the 800 VT is corrected, the
we use the compliance
formula
C static = VT/ [Pp –PEEP]
800 /[35-5]
800 /25
C static = 32 ml/cwp, so if the
last C static was 55 ml/ cwp,
he is getting worse
mode
CMV
VT
800
PIP
35
Pplateau
26
PEEP
flow
rate
5
60
lpm
question
• Your intubated patient
has the following
parameters:
mode
VT
PIP
P
plateau
CMV
800
45
24
PEEP
flow rate
5
60 lpm
3 hours ago, his RAW was 5.6
Is his bronchospasm getting better or worse?
answer
• To calculate the RAW
RAW = (P1-P2)/flow in
l/sec.
RAW = (PIP-PP)/60lpm
RAW = (45-24)/ l.0
l/sec
RAW = 21 cwp/1 l/sec
= 21cwp/liter/sec
The RAW is getting
worse
mode
CMV
VT
800
PIP
45
P
plateau
24
PEEP
flow
rate
5
60
lpm
question
• Your adult patient’s ET- tube is taped at 14
cm at the lip and you hear loud inspiratory
noise over the neck and the cuff will not
inflate even after you put 6-7 ml into the
cuff.
• What is going on?
answer
• This tube has migrated up, push it back
down to the proper level and reassess VS,
BBS and Sp02 to make sure the tube is
actually in the tracheal
question
• How would you treat a patient with CHF.
answer
• If the patient is in refractory hypoxemia but has a
reasonable pH and PaC02, you can get by with n-CPAP.
• If the patient’s VS, BBS and ABG don’t improve after 30
minutes on n-CPAP switch to BiPap.
• If the patient is in respiratory acidosis with refractory
hypoxemia, start BiPap but be ready to intubate and
ventilate with PEEP.
• If the patient’s VS, BBS and ABG don’t improve after 30
minutes on BiPap, intubate and ventilate with PEEP.
• Beta II agonists will not help.
• Diuretics and cardiac drugs can help
question
• What are the s/s of a patient whose
ventilator’s sensitivity is not set correctly?
answer
• If the patient is apneic, nothing
• If the patient has a respiratory effort there
will be visible and palpable s/s of
increased WOB
– On the pressure curve you will see the
pressure dips down lower than it should
– On the Pressure/volume loop, you will see the
pressure move into a negative number
without a change in volume
question
• Your patient has had a gradually dropping
compliance for the last few hours.
• His PIP is 50 and his Pplateau is 44.
• What do you suggest regarding his
settings.
answer
• assess this patient for ALI or ARDS
• get the pressures down to prevent
barotrauma.
• decrease the VT and adapt permissive
hypercapnea
• discover the optimal PEEP for this patient
and adjust both PEEP and Fi02 to get a
Pa02 above 60 torr