AARC Review for NBRC
Therapist Written RRT
Examination
Content Area III F:
Independently Modify Treatment Techniques
Based on the Patient’s Response
Tim Op’t Holt, Ed.D., R.R.T., AE-C, FAARC
Goal
Through patient scenarios and didactic
information, the participant will be able to
prepare for the NBRC Therapist Written
RRT Examination content outline section
III F: Independently Modify Treatment
Techniques Based on the Patient’s
Response
Objectives
The participant will be able to
independently modify the following
therapies, based on patient response:
– Lung expansion therapy
– Bland and medicated aerosol therapy
– Gas therapy
– Tracheobronchial hygiene, to include artificial
airway care and suctioning
– Maintenance of alarm settings and
mechanical dead space during mechanical
ventilation
Section Outline
1. Lung expansion therapy
2. Bland and medicated aerosol therapy
3. Oxygen therapy
4. Gas therapy
5. Tracheobronchial hygiene, to include
artificial airway care and suctioning
6. Maintenance of alarm settings and
mechanical dead space during
mechanical ventilation
Section 1: Lung Expansion
Therapy
Resorption atelectasis
– Associated with mucus plugging
Passive atelectasis
– Associated with decreased, monotonous tidal
volume and postoperative inactivity
– Alveoli shrink due to absence of periodic
hyperinflation, tachypnea, and hypopnea
– Surface tension increases to the point of
alveolar collapse
Section 1: Lung Expansion
Therapy
Clinical signs of atelectasis
– Hypoxemia
– Dyspnea
– Decreased breath sounds and late inspiratory
crackles
– Bronchial breath sounds as atelectasis
worsens
– Tachycardia
– Fever may be present, but not always
Section 1: Lung Expansion
Therapy
Selection of appropriate technique
– Indications for Incentive spirometry
Atelectasis
Conditions predisposing to atelectasis such as
upper abdominal or thoracic surgery
Restrictive lung defects associated with
quadriplegia and/or dysfunctional diaphragm
– Patient characteristics
Able to cooperate and understand instructions
Able to generate at least 33% of the predicted IC
Section 1: Lung Expansion
Therapy
Selection of appropriate technique
– Indications for IPPB
Atelectasis not responsive to other therapies
Patients unable to understand or participate in
other therapy for atelectasis or administration of
aerosol medications
– Patient characteristics
Obtundation, weakness
Pain, incompletely controlled by analgesia,
resulting in insufficient deep breathing
Unable to generate at least 33% of predicted IC
Section 1: Lung Expansion
Therapy
Modifying IPPB technique
Patient response Modification/intervention
Dizziness
Leaks
Ask the patient to slow their
breathing rate
Decrease goal pressure or
volume
Use a mouth seal or face
mask
Section 1: Lung Expansion
Therapy
Modifying IPPB technique
Patient response
Inspiratory time
too short
Inspiratory time
too long
Inadequate chest
excursion
Pain,
discomfort
Modification/intervention
Decrease inspiratory flow
Increase inspiratory flow
Increase pressure or volume
Decrease pressure or flow
Section 1: Lung Expansion
Therapy
Modifying IPPB technique
Patient response
Modification/intervention
Hypotension
Sudden
unconsciousness
Onset of chest
pain
Hemoptysis
Gastric distention
Discontinue treatment and
notify physician
Assure adequate
oxygenation and ventilation
Decrease goal volume or
pressure
Section 1: Lung Expansion
Therapy
Modifying IS technique
Patient response Modification/intervention
Dizziness,
tingling in
fingers, fatigue
Pain
Ask the patient to slow their
breathing rate
Assist patient with splinting of
operative site, assure adequate
analgesia
Section 1: Lung Expansion
Therapy
Modifying IS technique
Patient response Modification/intervention
Unable to
achieve goal
volume
Assist patient with splinting of
operative site
Assure adequate analgesia
Temporarily decrease goal
volume, assure patient
Section 1: Lung Expansion
Therapy
History and physical
A 54-year-old previously healthy female was
referred to a surgeon and presented with
abdominal pain that had previously been treated
medically without relief. Abdominal palpation
revealed mid-abdominal pain. On admission the
following information was available:
T = 99.0°F
P = 88/min
R = 14/min
SpO2 = 99%
Height = 66”
Weight = 78 kg (175 lbs)
Section 1: Lung Expansion
Therapy
An exploratory
laparotomy resulted in a
large midline abdominal
incision. The incision was
closed and dressed.
Following surgery, there
was a small amount of
serosanguinous drainage
into the dressing.
www.pvss.org/ Cases/renal/2.jpg
Section 1: Lung Expansion
Therapy
The respiratory therapist was called to evaluate
and treat the patient postoperatively.
Three hours postoperatively, vital signs were:
–
–
–
–
T = 100.8°F
P = 98/min
R = 20/min and shallow
Room air SpO2 = 92%; 98% with 3L/min. nasal
cannula
Physical examination revealed the following:
– Observation revealed an awake, drowsy female, with
abdominal pain. Minimal abdominal excursion, fair
chest wall excursion, unable to take a deep breath.
Weak, dry cough.
Section 1: Lung Expansion
Therapy
– Abdominal pain on
palpation, no
abdominal excursion,
2 cm. chest wall
excursion.
– Breath sounds clear
and decreased to
auscultation in the
apices; crackles in the
left base.
– A chest radiograph
revealed the following:
http://www.meddean.luc.edu/lumen/meded/medicine/pulmonar/images/cxr2/80a.jpg
Section 1: Lung Expansion
Therapy
The initial order was for incentive
spirometry, q1° while awake
Measured Inspiratory Capacity = 700 mL
Section 1: Lung Expansion
Therapy
Question 1
Using the data given in this case scenario,
what therapy should the therapist
perform?
A. Incentive spirometry, q1 hour.
B. Chest physical therapy to the LUL and
LLL
C. IPPB with a goal volume of 2.0L
D. IPPB with a pressure of 10 cm H2O
Section 1: Lung Expansion
Therapy
Question 2
During IPPB, the patient complains of abdominal pain and
states, ”the breath is too long.” The therapist’s most
appropriate actions are to:
I. Contact the nurse for an analgesic
II. Increase the inspiratory flow
III. Decrease the peak pressure
IV. Use a mask to deliver the therapy
A. I, II only
B. II, III only
C. III, IV only
D. I, III only
Section 1: Lung Expansion
Therapy
Question 3
During IPPB with a pressure-controlled ventilator,
the therapist measures a volume of 1.0L. To
obtain a volume of 1.5L, the therapist should
increase the:
A. tidal volume setting
B. inspiratory flow
C. inspiratory pressure
D. trigger sensitivity
Section 1: Lung Expansion
Therapy
Question 4
Thirty-six hours after surgery, the patient has an
inspiratory capacity of 1.1L. What is the
therapist’s most appropriate action?
A. Increase the inspiratory pressure during IPPB
B. Add chest physical therapy to the left chest
C. Change therapy to incentive spirometry with a
goal of 2.0L, q1 hour.
D. Change therapy to coughing and deep
breathing every hour.
Section 1: Lung Expansion
Therapy
Question 5
The patient is performing incentive spirometry and
complains of tingling in her fingers and
dizziness. The therapist should:
A. explain that this is a normal outcome of
therapy.
B. encourage the patient to slow her breathing
rate.
C. pause 5 seconds at the end of each
inspiration.
D. have the patient perform IS every 2 hours.
Section 1: Lung Expansion
Therapy
KEY
1. C
2. D
3. C
4. C
5. B
Section 1: Lung Expansion
Therapy
Question 1 analysis:
If you answered C, you are right. Since the patient
had an IC < 33% of predicted, IPPB was
indicated.
Answer A: IS would not have been effective.1
Answer B: CPT was not indicated, as the patient’s
cough was dry and CPT would have been
painful.
Answer D: IPPB should be volume-oriented.
Section 1: Lung Expansion
Therapy
Question 2 analysis:
If you answered D, you are right. The patient was
in pain and needed an analgesic. Also, the
inspiratory time was too long. To make the
breath more comfortable and decrease
inspiratory time, the therapist should decrease
the peak pressure.
Increasing inspiratory flow would maintain an
uncomfortable pressure.
A mask was not indicated, as there was no
mention of a leak.
Section 1: Lung Expansion
Therapy
Question 3 analysis:
If you answered C, you are right. Tidal
volume will increase if the inspiratory
pressure is increased.2,3
It is not possible to independently increase
the tidal volume on a pressure-controlled
ventilator.
Increasing inspiratory flow or sensitivity will
not increase tidal volume.
Section 1: Lung Expansion
Therapy
Question 4 analysis:
If you answered C, you are right. The patient
has an adequate IC and can perform IS
appropriately.4
More IPPB and coughing and deep
breathing are possible, but not as effective
as IS at this point.
CPT is not indicated, as there is no evidence
of secretions.
Section 1: Lung Expansion
Therapy
Question 5 analysis:
If you answered B, you are right. Tingling and
numbness is caused by hyperventilation.
Slowing the respiratory rate will relieve this.5
Hyperventilation is not a normal event during IS.
Instituting an inspiratory pause is important, but
not the answer. Decreasing frequency of therapy
does not treat hyperventilation.
Section 1: Lung Expansion
Therapy
References
1. Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed. St.
Louis, Mosby; 2004:880.
2. Ibid:876.
3. White GC. Basic Clinical Lab Competencies for
Respiratory Care: An Integrated Approach.
Clifton Park, NY, Delmar;2003:335-337.
4. Reference 1:870.
5. Reference 1:868.
Section 1: Lung Expansion Therapy Clinical
Practice Guidelines
AARC Clinical Practice Guideline: IPPB.
http://www.rcjournal.com/contents/05.03/
05.03.0540.asp
AARC Clinical Practice Guideline:
Incentive Spirometry
http://www.rcjournal.com/online_resourc
es/cpgs/ispircpg.html
Section 2: IIIF3 Bland and
Medicated Aerosol Therapy
Bland aerosol therapy defined
– An aerosol of sterile distilled water or
hypotonic, isotonic or hypertonic saline
– May be delivered to the upper airways
(MMAD >5 _m), cool or warmed
– Hypo-and hypertonic saline for sputum
induction, MMAD1-5 _m
– Bypassed upper airway, MMAD 2-10 _m, cool
or warmed
AARC CPG: Bland Aerosol Administration 2203 revision and update. RCJ May
2003;48(5):529-33.
Bland Aerosol Therapy
Equipment
– Large volume aerosol generator (nebulizer)
Pneumatically powered
Control particle size by jet orifice size and baffling
FiO2 is controlled by a variable air entrainment port
Therapy is to be discontinued if the patient begins
to wheeze due to particle reaction
Bland Aerosol Therapy
Equipment
– Ultrasonic nebulizer
Electrically powered
Particle size 1/% signal frequency; MMAD 2.5 or 4-6 _m
Mist density % signal amplitude; up to 7 mL/min.
Blower delivers mist to the patient
More frequently used for sputum induction with hypertonic
saline
Present an infection hazard unless frequently decontaminated
(q 6 days)
Discontinue therapy if patient begins to wheeze
Bland Aerosol Therapy
Airway Appliances
– Aerosol mask and face tent for patients with
intact upper airway
– T-piece or Briggs adapter with reservoir for
orally intubated patients
– Tracheostomy mask for patients with a
tracheostomy tube
No traction, allows condensate to escape away
from the airway
Bland Aerosol Therapy
Aerosol output
– Large volume nebulizer
Unheated, output is 26-35 mg H2O/L
Heated, output is 33-55 mg H2O/L
2-3L/day depending on temperature and source
gas flow
– Ultrasonic nebulizer
Mist density % signal amplitude; up to 7 mL/min.
– Adjusted based on mucus viscosity, ease of
suctioning, and patient subjective response
Bland Aerosol Therapy
Aerosol temperature
– Unheated aerosol is cooler than ambient
temperature
Appropriate for patients breathing through native
airway
If patient complains that aerosol is too cold, a
heater may be applied
– Heated aerosol is ~ 88-95°F with a heater that
warms liquid just prior to aerosolization
Useful when upper airway is bypassed and for
sputum induction
Bland Aerosol Therapy
History and physical
A 55-year-old previously healthy male was referred
to a thoracic surgeon due to a lung mass.
Following surgery the patient developed
pneumonia, which required an additional 10
days of antibiotic therapy and mechanical
ventilation. On day 10, ventilator parameters
were:
Mode: VC-SIM/PSV
FiO2: 0.4
Mandatory rate: 6/min
PEEP: 5 cm H2O
Set tidal volume: 700 mL PSV: 8 cmH2O
Bland Aerosol Therapy
Question 1
Since the patient could not be extubated, a jet
nebulizer was used to deliver aerosol to the
patient using a T-piece and 100 cc reservoir.
Tenacious secretions made suctioning at -120
mm Hg difficult. The therapist should:
A. replace the jet nebulizer with an ultrasonic
nebulizer.
B. attach a heater to the jet nebulizer.
C. lengthen the reservoir tubing.
D. make the suction pressure more negative.
Bland Aerosol Therapy
Question 2
This patient required a tracheotomy and was weaned from
the ventilator. A T-piece and reservoir were used to
deliver aerosol from a jet nebulizer. The nurses have had
to adjust the aerosol tubing and change the dressing at
the tracheotomy site frequently. The therapist should:
A. clean the tracheotomy site with peroxide.
B. contact the surgeon.
C. replace the T-piece with a tracheostomy collar.
D. attach a heater to the nebulizer.
Medicated Aerosol Therapy
Delivery of medications to the lower
airways in the form of:
– A liquid aerosol using a small volume gas
powered nebulizer (SVN), vibrating mesh
nebulizer, or other electrically-powered SVN
– A liquid aerosol using a metered dose inhaler
(MDI) with or without a valved holding device
– A dry powder, using a dry powder inhaler
(DPI)
Medicated Aerosol Therapy
Drug categories
– Beta adrenergic agents (albuterol, pirbuterol,
bitolterol, salmeterol)
– Anticholinergic agents (ipratropium,
tiotropium)
– Corticosteroids (fluticasone, beclomethasone,
budesonide, etc.)
– Mucokinetics (acetylcysteine, DNAse)
Small Volume Nebulizers
Factors favoring SVN
50 psi @ 6-10 L/min
source gas flow available
Any breathing pattern or
level of cooperation
Any combination of liquid
medication
Variable dilution
Mouthpiece or mask
delivery with mouth
breathing
Factors limiting SVN
MDI or DPI available for
same drugs
Ambulatory patient
Drug only available as MDI
or DPI (i.e
salmeterol/fluticasone)
Treatment time for SVN
Increased cost of
equipment for SVN
Variation in SVN
output/dependence on
pressure and flow for
optimal particle size
Infection
Metered Dose Inhalers
Factors favoring MDI
Short treatment time
As effective as SVN
Now the device of
choice, assuming
drug availability and
patient cooperation
Factors limiting MDI
Technique-dependent
Patient teaching time
Often requires a
valved holding
chamber or spacer
Several different drug
MDIs may be required
CFC propellants
Need to prime/drug
loss
Valved Holding Chambers
The MDI is actuated into the VHC to
– slow the particles and allow propellant evaporation to
improve airways deposition
– decrease reliance on hand-breath coordination
– decrease pharyngeal deposition
The plastic VHC should be washed in soap and
water at least monthly to clean and decrease
electric charge
A reservoir must be used when administering an
MDI to a mechanically ventilated patient
Dry Powder Inhalers
Factors favoring DPI
Short treatment time
As effective as SVN
Now the device of
choice, assuming
drug availability and
patient cooperation
No CFC
Factors limiting DPI
Humidity causes drug
clumping
Technique dependent
– Patient must maintain
a designated
inspiratory flow
Patient teaching time
Drug Dilution
The amount of diluent added to a liquid
drug to be aerosolized does NOT
decrease the dose delivered to the patient
– It only increases the time for nebulization
– The dose of active drug remains the same
Decreasing the amount of drug WILL
decrease the dose delivered to the patient
– Such as using _ of a unit dose or using 0.25
mL of a 0.5% solution instead of a full unit
dose or 0.5 mL
Drug Dilution
Pneumatic SVNs require at least 1 mL of
solution to nebulize (dead volume)
– Optimal total SVN volume is > 4mL
Vibrating mesh nebulizers nebulize drops
of solution (no dead volume)
– Failure to dilute results in full mg dose
delivered in a few seconds
– May cause side-effects
– Dilute conventionally
Medicated Aerosol Therapy
Question 3
An employed, ambulatory patient with COPD is to take
treatments with albuterol and ipratropium QID following
hospital discharge. What drug delivery method should
the therapist teach to the patient?
A. metered dose inhaler with valved holding chamber
B. small volume nebulizer with compressor
C. dry powder inhalation
D. metered dose inhaler with closed-mouth technique
Medicated Aerosol Therapy
Question 4
A patient with mild persistent asthma returns to the clinic
after a two-week trial of fluticasone (Flovent) 110, 1 puff
BID. His symptom diary shows no improvement. What
should the respiratory therapist do FIRST:
A. Increase the fluticasone dose to 2 puffs BID.
B. Switch the patient to budesonide (Pulmicort) by SVN.
C. Have the patient demonstrate proper spacer
cleansing.
D. Check and reinforce proper MDI technique.
Medicated Aerosol Therapy
Question 5
A patient with steroiddependent COPD is
receiving mechanical
ventilation. She receives
albuterol/ipratropium unit
dose by SVN Q4 hours
and 1 puff of Flovent
(fluticasone) 220 BID
using an MDI using the
adapter shown here:
Medicated Aerosol Therapy
Question 5 continued
Her flow-volume loop is
shown here:
What should the
respiratory therapist
do first?
Flow
L/min
Vol.
(L.)
Medicated Aerosol Therapy
Question 5 continued
A. Replace the adapter with a chamber spacer for
the fluticasone treatments.
B. Contact the physician for an order to double the
fluticasone.
C. Contact the physician for an order to double the
dosage of albuterol/ipratropium.
D. Change the inspiratory flow pattern to
decelerating ramp.
Section 2: Bland and Medicated
Aerosol Therapy
Key
1. B
2. C
3. A
4. D
5. A
Section 2: Bland and Medicated
Aerosol Therapy
Question 1 analysis
If you answered B you are right. A heater will
increase the temperature of the delivered gas
and increase it’s water vapor content. This is
supposed to increase water to the airway and
make the inhalation of the aerosol more
comfortable.
A USN will also add water, perhaps too much, and
it is difficult to adjust the FiO2.
Lengthening the reservoir tubing helps stabilize
FiO2.
Making suction pressure more negative increases
the chance of trauma to the airway.
Section 2: Bland and Medicated
Aerosol Therapy
Question 2 analysis
C is correct. A T-piece will pull on a tracheostomy
tube, possible causing bleeding and
inflammation. Always use a tracheostomy collar
in this case.
Cleaning the tracheostomy site only will
temporarily make the site look better.
The surgeon will tell the therapist to wait for his
next visit, prolonging corrective action.
A heater is indicated, but the tracheostomy collar is
most important at this time.
Section 2: Bland and Medicated
Aerosol Therapy
Question 3 analysis
A is the best answer. MDIs with a spacer are the
delivery device of choice for ambulatory patients,
and these drugs are available as MDIs.
A SVN and compressor tethers the patient to his
home and is unnecessarily expensive.
These drugs are not available as DPIs
The closed mouth technique is suboptimal, as
much of the medication is deposited in the
oropharynx.
Section 2: Bland and Medicated
Aerosol Therapy
Question 4 analysis
D is the best answer. Because MDI therapy is
dependent upon correct technique, this is the
first and cheapest thing to check when the
patient complains of therapy ineffectiveness.
If technique is appropriate, the dosage may need
to be increased.
Changing therapy to another drug and increasing
the cost, especially when the problem is inhaler
technique, is unproductive.
After only two weeks, it is unlikely that the spacer
will have needed cleaning.
Section 2: Bland and Medicated
Aerosol Therapy
Question 5 analysis
A is correct. Narrow barrel and elbow adapters
allow delivery of almost no drug and should
always be replaced by a spacer chamber. The
flow-volume loop shows air-trapping,
characteristic of bronchospasm.
Doubling the fluticasone with this administration
device wastes the medication faster
The dose of albuterol/ipratropium is already
appropriate
Increasing inspiratory time is appropriate, but will
not solve the problem of poor drug delivery.
Section 2: Bland and Medicated
Aerosol Therapy
References
AARC Clinical Practice Guideline: Bland aerosol
administration-2003 revision and update. RCJ
2003;48(5):529-533
AARC Clinical Practice Guideline: Selection of
aerosol delivery device. RCJ 1992;37:891-897.
Rau JL. Respiratory Care Pharmacology 6th ed. St.
Louis, Mosby;2002:77-78.
Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed. St.
Louis, Mosby; 2004:751-755,766-782.
Section 2: Bland and Medicated
Aerosol Therapy
Other resources
AARC Professor’s Rounds: Getting the Most from
the Mist: Current and Future Aerosol Delivery.
http://www.aarc.org/education/professors_round
s_05/
AARC Webcasts:
Pneumatic aerosol devices: Past, present and
future.
Liquid aerosol drug delivery: Nebulization for the
21st century. AARC.org/education/webcast
Section 3: IIIF4 Oxygen Therapy
Changing the “mode” of oxygen
administration
– Changing from high to low flow therapy
– Changing from low to high flow therapy
– Changing devices within high/low flow
categories
– Changing from ambient oxygen therapy to
continuous positive airway pressure
Oxygen Therapy
Changing from high to low flow therapy
– Initial patient condition consists of an unstable
ventilatory pattern or high minute ventilation, unstable
vital signs, and/or unknown cause of mild-moderate
hypoxemia
– An air entrainment mask is often chosen to deliver an
FiO2 to keep SpO2 > 92%
FiO2 may be > 30%
– After initial therapy, stable ventilatory pattern, vital
signs, and FiO2 < 35%: therapy could be changed to
a low flow device (nasal cannula) at 3-5 L/minute,
concurrent with pulse oximetry to assure oxygenation
Oxygen Therapy
Changing from low to high flow therapy
– Initial patient condition consists of a stable ventilatory
pattern or normal minute ventilation, stable vital signs,
and/or known cause of mild hypoxemia
– A low-flow device (nasal cannula) is in use at 2-5
L/minute.
– A sudden or gradual deterioration of vital signs and
SpO2, ventilatory pattern instability: therapy should be
changed to an air entrainment mask at an FiO2 > 0.4
concurrent with pulse oximetry to assure oxygenation
Oxygen Therapy
Changing high flow devices, beginning with the
air entrainment mask
– In the event of tracheostomy or intubation, without
mechanical ventilation, use a heated air entrainment
nebulizer with a tracheostomy collar or T-piece.
– at an appropriate FiO2, as the FiO2 requirement
increases, consider an open blending system to
provide a greater total flow (> 60 L/minute)
– In the event of inspissated secretions, an air
entrainment nebulizer at the same FiO2 as the
entrainment mask may be used.
Oxygen Therapy
Changing low flow devices, beginning with the
nasal cannula
– In sudden onset of respiratory distress, unstable vital
signs, and SpO2 < 90%: change to a nonrebreather
mask at >10 L/minute concurrent with pulse oximetry
to assure oxygenation. This is usually short-term
while determining necessity for intubation.
– In mouth-breathing patients with mild-moderate
hypoxemia and congested nasal airway: change to a
simple mask at 5-8 L/minute, concurrent with pulse
oximetry to assure oxygenation; usually short-term as
it is uncomfortable.
Oxygen Therapy
Changing from ambient oxygen to CPAP
– Hypoxemia refractory to ambient oxygen
therapy with a nonrebreather mask
– Impending or established hypoxemic
respiratory failure
– Heart failure, early ARDS, atelectasis
unresponsive to ambient oxygen therapy
– PaO2 < 50-60 mm Hg on > 50% oxygen
– P/F ratio < 300
– Dyspnea
Oxygen Therapy
Adjusting flow and FiO2
– Flow is adjusted on low flow devices until the:
desired SpO2 is achieved, or
FiO2 delivery limits are reached, or
mode or delivery device should be changed
protocol is satisfied
– Flow and FiO2 are adjusted on high flow devices until
the:
desired SpO2 is achieved, or
FiO2 delivery limits are reached, or
mode or delivery device should be changed
protocol is satisfied
Oxygen Therapy
Air/Oxygen blenders
– Provide 50 psi gas at an FiO2 of 0.21-1.0 at flows up
to 180 L/minute
– Used when high flow oxygen therapy is desired at
flows in excess of the air entrainment mask or
nebulizer
80% oxygen from an air entrainment mask has an air:oxygen
entrainment ratio of 0.3:1. If the patient has a minute
ventilation of 12 L/minute, the flow needed is 36 L/minute
(flow needed = 3 x VE). Source gas flow would have to be 28
L/minute, beyond the operable range of most air entrainment
nebulizers and masks.
Oxygen Therapy
Air/Oxygen blenders
– Provide mixed gas for
ambient or CPAP
systems
– In both open and
closed systems
(pictured here) an antiasphyxia valve must
be in place, in the
event of gas failure
Oxygen Therapy
Air/Oxygen blenders
– FiO2 must be checked at least each shift
– Unstable or incorrect FiO2 must be followed
by exchanging the blender
– Blender alarms indicate a loss of one source
gas
Assure connection to both oxygen and air
Assure air and oxygen sources have pressures
within specifications
Test low air and oxygen source gas alarms by
disconnecting each source
Oxygen Therapy
Liquid oxygen
systems
– 1 ft3 of liquid oxygen =
860 ft3 of gaseous
oxygen
– Storage unit is much
like a thermos, with a
liquid oxygen storage
bottle suspended in a
vacuum
– Portable and in-home
storage dewars
Portable
dewar
Large storage dewar
Oxygen Therapy
Liquid oxygen systems
– Oxygen supply company fills the large storage dewar
as needed
45-100 lbs of liquid oxygen
Up to 34,000 L gaseous oxygen
– Patient may use oxygen from the large dewar, or from
a portable dewar, refillable from the large dewar.
5-14 lbs.
5-8 hours of oxygen at 2 L/minute
– Service pressure is 20-25 psi
– Gas flow is metered by an adjustable flow restrictor, _
- 15 L/minute
Oxygen Therapy
Liquid oxygen systems
Computing duration of flow
– Size of dewar in lbs x fraction of full = lbs.
available
– lbs. available x 344 L gas/lb. = liters gas
available
– liters available/flow (L/min) = minutes
available at that flow
Oxygen Therapy
Liquid oxygen systems
Advantages
Disadvantages
Large volumes in a small
space
Low pressure system
Refillable portable system
allows ambulation
Frequent deliveries necessary
Oxygen is constantly venting
when not in use (waste)
Contact with liquid causes
burns
Potential difficulty when filling
portable unit
High cost
Less likely to be covered by
insurance
Oxygen Therapy
Oxygen concentrators
– Electrically powered
– Removes oxygen from
the air by passing air
through molecular
sieves
– O2 concentration
1-2 L/min: 92-95%
3-5 L/min: 85-93%
– If FiO2 falls below
85%, sieve canisters
are replaced by home
care provider
http://www.ucanhealth.com/graph/m400-410.jpg
Oxygen Therapy
Oxygen concentrators
Advantages
Disadvantages
No waste or loss
Low pressure system
(15 psi)
Cost-effective when in
continuous use
No oxygen deliveries
Covered by insurance
Require electrical
supply, so backup
oxygen cylinder is
required
FiO2 1/% flow
Increased power costs
Oxygen Therapy
Question 1
The respiratory therapist is checking oxygen on an
elderly patient with heart failure who is using a
nasal cannula at 3L/min. The therapist notes that
the patient’s pulse is weak, SpO2 is 83%, and
the patient is poorly responsive. The therapist
should:
A.
B
C.
D.
Increase the oxygen flow to 4 L/min.
Apply a nonrebreather mask at 12 L/min.
Apply a 40% air entrainment mask
Apply a simple mask at 8 L/min.
Oxygen Therapy
Question 2
A patient with lung cancer arrives on the medical
unit from the ICU wearing a 50% air entrainment
mask at 12 L/min. The patient’s color is good
and his SpO2 is 100%. The therapist should:
A.
B.
C.
D.
continue present oxygen therapy.
apply a nonrebreather mask at 12 L/min.
decrease the FiO2 to 35%
apply a nasal cannula at 2 L/min.
Oxygen Therapy
Question 3
A 35-year-old male who crashed a motorcycle into a
freeway overpass is seen by the respiratory therapist
36 hours after the crash. The patient is dyspneic and
has an SaO2 of 85% on a 50% air entrainment mask.
What is the optimal therapy at this time:
A. mask CPAP.
B. an increase in the FiO2 to 0.7.
C. mechanical ventilation.
D. a nonrebreather mask
Oxygen Therapy
Question 4
A patient’s liquid oxygen system holds 30 lbs.
when full. It now reads _ full. How much longer
will the supply last running at 4 L/min?
A.
B.
C.
D.
1.8 days
7.2 days
43 hours
645 minutes
Oxygen Therapy
Question 5
A patient with COPD is using an oxygen
concentrator at 2 L/min. The respiratory therapist
measures the FiO2 and finds that it is 0.85. The
therapist should:
A.
B.
C.
D.
increase the liter flow.
have the sieves changed.
note the FiO2 and continue with his checks.
clean the air filter on the concentrator.
Section 3: Oxygen Therapy
KEY
1. B
2. C
3. A
4. D
5. B
Oxygen Therapy
Question 1 analysis
Answer B is correct. The patient is severely
hypoxemic, has a weak pulse, and
decreased sensorium. While awaiting
definitive medical therapy, the patient’s
oxygenation status must be improved by
greatly increasing FiO2. The other options
are incorrect because they do not offer as
high an FiO2 as the nonrebreather mask.
Oxygen Therapy
Question 2 analysis
The correct response is C. Since the
patient’s color and SpO2 are good, the
FiO2 can be decreased using SpO2 as a
guide. Responses A and B would increase
the FiO2 which is not indicated. Response
D represents a decrease in FiO2 that may
be too great for the patient to tolerate at
this time.
Oxygen Therapy
Question 3 analysis
The correct response is A. The first 24-36 hours
after trauma represents the latent period for
ARDS. Once the patient becomes tachypneic
and refractory hypoxemia is established, the
only way to improve oxygenation is to implement
CPAP, either by mask or artificial airway.
Options B and D increase FiO2, but do nothing
to increase alveolar surface area. Mechanical
ventilation is a possibility, but may be more than
the patient needs at this time.
Oxygen Therapy
Question 4 analysis
– Size of dewar in lbs (30) x fraction of full (.25)
= lbs. available (7.5 lbs.)
– lbs. available (7.5) x 344 L gas/lb. = liters gas
available (2580 L.)
– liters available (2580 L.)/flow (L/min) (4L/min.)
= minutes available at that flow (645 min.)
The correct response is D.
Oxygen Therapy
Question 5 analysis
The correct response is B. When the sieves
become “full” of nitrogen, they are unable
to filter out more nitrogen, so the zeolite in
the sieve canisters must be replaced. The
other responses do nothing to correct this
problem. Failure to replace the zeolite will
result in a further decrease in the FiO2
delivered by the concentrator.
Section 3: Oxygen Therapy
References
Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed. St.
Louis, Mosby; 2004:833-852,1254-1260.
AARC Clinical Practice Guideline: Oxygen therapy
for adults in the acute care facility-2002 revision
and update. RCJ 2002;47(6):717-720.
Selecting the Most Appropriate O2 Device for Your
Patient. AARC Webcast.
http://www.aarc.org/education/webcast/index.asp
Section 4: IIIF5 Specialty Gas
Therapy
Helium/Oxygen (Heliox) therapy
– Indications
Large airway obstruction
Dyspnea and tachypnea in COPD
Acute upper airway obstruction
Asthma with acute respiratory failure
Anesthesia through small endotracheal tubes
Postextubation stridor
– Effects
Decreases the work of breathing by carrying
oxygen in a gas less dense than nitrogen
Specialty Gas: Heliox
Guidelines for Use
– Always mix Helium with > 20% oxygen
– Most common mixes are 80/20 and 70/30
Helium/Oxygen
– Use for as long as necessary in
postextubation stridor
Treat concurrently with steroids and racemic
epinephrine
Specialty Gas: Heliox
Modes of administration
– Use a nonrebreathing system, simple mask, or
nonrebreather mask
– Always check the FiO2 of the cylinder before use, to
assure the correct FiO2
– May be administered with a ventilator but it confounds
the volume delivery systems of most ventilators, so
should be used only with caution and experience
– May be bled into the mask of an NPPV system
Recent study does not demonstrate decreased intubation
rate or ICU stay
Specialty Gas: Heliox
May be administered
using a commercially
available system (GE
Aptaér Heliox
Delivery System)
Nonrebreathing
system
For spontaneouslybreathing patients
http://www.gehealthcare.com/usen/respiratory_care/images/ac_80.jpg
Specialty Gas: Heliox
Modes of
administration
– During aerosol therapy
Improves aerosol
delivery: improves
FEV1, PEF, decreases
intubation rate
Don’t let air into the
system
Run the nebulizer at 11
L HeO2/min.
Aerogen nebulizer may
also be used
Specialty Gas: Heliox
Adjusting Heliox flow
– Correction factors for heliox use through an oxygen
flowmeter
1.8 for 80/20 heliox
1.6 for 70/30 heliox
For example, if 80/20 heliox is being delivered with an
oxygen flowmeter set to 10 L/min., there are actually 18
L/min. of heliox.
Adjusting Heliox concentration
– Use 70/30 heliox in the treatment of airway
obstruction with accompanying hypoxemia
Specialty Gas: Heliox
References
Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed.
St. Louis, Mosby; 2004:858-859.
AARC Webcast: Heliox Therapy.
http://www.aarc.org/education/webcast/ind
ex.asp
Specialty Gas: Nitric Oxide
Indications
– Disorders where blood flow to ventilated
alveoli is decreased
Effect is limited to the pulmonary arteries
Approved only for use in neonates
– Treatment of term and near-term neonates
with hypoxic respiratory failure with pulmonary
hypertension
Specialty Gas: Nitric Oxide
Mode of administration
GE INOvent
–
–
–
–
Adjustable [NO]
Limits production of NO2
Monitors [NO] and [NO2]
Adds NO to the inspiratory
limb of the ventilator
– Most effective when
combined with HFOV
– Scavenging unnecessary
http://www.gehealthcare.com/usen/anesthesia/products/anelifesupport_inovent.html
Specialty Gas: Nitric Oxide
Adjustment of concentration and flow
– Recommended initial dose is 20 ppm
– < 14 days or until underlying oxygen desaturation has
improved
– Dose can often be reduced to 5 ppm after the initial 4
hours
– Higher doses did not improve effect and increased the
hazard of NO2
– starting at a high dose and working down is more
effective than starting at a low dose and working up
Specialty Gas: Nitric Oxide
Withdrawal of therapy
– Reduce concentration to lowest effective dose
(< 5ppm)
– Patient should be hemodynamically stable
– Oxygenation should be stable with < 40%
oxygen
– Hyperoxygenate with 60-70% oxygen before
removing NO
– Prepare to provide hemodynamic support if
needed
Specialty Gas: Nitric Oxide
References
Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed.
St. Louis, Mosby; 2004:855-858.
AARC Webcast: Nitric oxide therapy.
http://www.aarc.org/authenticate.asp?/edu
cation/webcast/archives/nitric_oxide/index.
asp
Specialty Gas
Question 1
What flow of Heliox should be used to power a
small volume nebulizer for bronchodilator
administration?
A. 6 L/min.
B. 8 L/min
C. 11 L/min.
D. 15 L/min
Specialty Gas
Question 2
What is the correct flow setting for an oxygen
flowmeter to deliver a 70/30 heliox at 18
L/minute?
A. 18 L/min.
B. 11 L/min.
C. 32 L/min.
D. 29 L/min.
Specialty Gas
Question 3
A patient with asthma is inhaling 80/20 heliox with
a simple mask. The SpO2 is 90%. The
therapist should:
A. increase the heliox to 70/30.
B. deliver the heliox with a nonrebreather mask.
C. decrease the heliox to 70/30 and use a
nonrebreather mask
D. decrease the heliox to 70/30 and use an air
entrainment nebulizer set at 80% oxygen.
Specialty Gas
Question 4
What initial dose of nitric oxide should the therapist
administer to an infant with pulmonary
hypertension?
A. 100 ppm
B. 80 ppm
C. 40 ppm
D. 20 ppm
Specialty Gas
Question 5
An infant who is receiving 5 ppm nitric oxide has a stable hemodynamic
status and a PaO2 of 60 mm Hg on an FiO2 of 0.38. What are the
therapist’s most appropriate actions?
I. Prepare to hyperoxygenate the infant.
II. Turn the nitric oxide off.
III. Decrease the FiO2 to 0.35
IV. Increase the nitric oxide to 8 ppm
A. I, II only
B. III, IV only
C. I, IV only
D. II, III only
Specialty Gas
Key
1. C
2. B
3. C
4. D
5. A
Specialty Gas
Question 1 analysis
C is the correct response, according to Hess
in the AARC Webcast on heliox. Lower or
higher values decreased aerosol
deposition.
Specialty Gas
Question 2 analysis
The correct answer is B, 11 L/minute. If one
wants an 18 L/min. flow of 70/30 heliox,
the desired oxygen flowmeter setting = the
quotient of the desired heliox flow/1.6:
Flow = 18/1.6 = 11.25 L/min.
Specialty Gas
Question 3 analysis
The correct response is C. The patient is
hypoxemic and is receiving heliox using a
less than optimal delivery device. The
therapist should increase the FiO2 by
obtaining a cylinder of 70/30 heliox and
assure a higher concentration of source
gas by using a nonrebreather mask.
Specialty Gas
Question 4 analysis
The correct response is D. The other
concentrations of NO are higher than the
recommended dose and have not been
shown to improve oxygenation index,
survival, or less need for ECMO. Higher
doses are also associated with an
increase in nitrogen dioxide, a toxic
byproduct of NO administration.
Specialty Gas
Question 5 analysis
The correct response is A. This infant has an
acceptable oxygenation status and is on the
lower end of the NO dose range, so is ready to
be weaned from NO. The therapist is to prepare
for temporary hyperoxygenation and to
discontinue the NO. Decreasing the FiO2 may
cause hypoxemia. Increasing the [NO] is not
indicated.
Section 5: IIIF6, 7, 8 Bronchial Hygiene
Therapy, Management of Artificial Airways,
and Suctioning
Patient positioning and duration of bronchial
hygiene therapies
Coordination of sequencing of bronchial hygiene
therapies
Management of artificial airways to:
–
–
–
–
Change type of humidification equipment
Initiate suctioning
Control cuff inflation
Perform tracheostomy care
Section 5: IIIF6, 7, 8 Bronchial Hygiene
Therapy, Management of Artificial Airways,
and Suctioning
Suctioning, related to
– Altering the frequency and duration
– Changing the type and size of catheters
– Changing pressure
– Use of irrigating solutions
Bronchial Hygiene Therapy
Refers to postural drainage therapy (CPT),
cough techniques, PEP techniques, and
HFCWO
Altering patient position in unilateral lung
disease
– Poor oxygenation associated with a particular
position, i.e. while lying on right side; would indicate
atelectasis/consolidation on the right side. Lying on
the left side may improve oxygenation.
Altering patient position in ARDS
– Prone positioning 1° for the purpose of improving
oxygenation, 2° for postural drainage
Bronchial Hygiene Therapy
Altering patient position for secretion
clearance or atelectasis
– Indicated for any of the following in a lobe or
segment not currently receiving CPT
Radiographic indication of consolidation or
atelectasis
Coarse crackles
Bronchoscopic evidence of secretions
Rhonchial fremitus
Bronchial Hygiene Therapy
Duration of bronchial hygiene therapies
– 3-15 minutes in each position, as tolerated
– Total treatment time of 30-40 minutes
– Reevaluate every 48-72 hours
– Mechanical insufflation-exsufflation consists
of five cycles followed by secretion removal
Bronchial Hygiene Therapy
Coordination of sequencing
– Hygiene therapy follows medicated aerosol or
may be concurrent with bland aerosol therapy
– “secretion mobilization” phase is first
CPT, Huffing, slow exhalation through PEP device
Slow, deep breathing at tidal volume > normal
through PEP device
– “secretion elimination” phase follows
Coughing
Rapid exhalation through vibratory PEP device
(FlutterTM or AcapellaTM)
Bronchial Hygiene Therapy
Reference
Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed.
St. Louis, Mosby; 2004:888-904.
Artificial Airway Management
Humidification equipment
– Heated humidifier
May be used during mechanical ventilation or while
spontaneous breathing
Delivers water vapor
Require a high-flow of mixed gas (blender and
flowmeter) if not used with a ventilator
Constant airway temperature is maintained
Can deliver 100% RH at body temperature
Long-term mechanical ventilation (>96 hours)
When the HME is contraindicated
Artificial Airway Management
Humidification equipment
– Heated bland aerosol
Air entrainment nebulizer
Patients not receiving mechanical ventilation
Aerosol temperature is controlled by a heater
33-55 mg H2O/L water output
Delivers aerosol through a T-piece or
tracheostomy collar
Easy, from an equipment setup point-of-view
Adjustable, stable FiO2, unless a high flow and
high FiO2 are necessary
Artificial Airway Management
Humidification equipment
– Heat and Moisture exchanger (HME)
The two most efficient types are the hygroscopic
condenser and hydrophobic condenser
Contraindications:
–
–
–
–
Thick, copious or bloody secretions
Expired VT < 70% inspired VT (bronchopleural fistula)
Body temperature < 32°C
Spontaneous VE > 10L/min.
Remove HME from circuit when administering
aerosolized medications
May be used for all mechanical ventilation unless
contraindicated
Artificial Airway Management
Humidification equipment reference
Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed.
St. Louis, Mosby; 2004:741-753.
Artificial Airway Management:
Indications for Suctioning
Coarse crackles
Radiographic evidence of
secretions
Changes in monitored
pressure/flow graphics
Increased PIP (VCV)
Decreased VT (PCV)
Atelectasis or
consolidation, consistent
with secretions
Visible secretions in the
airway
Observed increase in
WOB
Deteriorating ABGs
Need to obtain a sputum
specimen
Need to maintain artificial
airway patency
Need to stimulate cough
Artificial Airway Management:
Cuff Care
An increase in cuff
pressure or volume
may be indicated
when:
There is an audible leak
There are bubbles at the
mouth
Exhaled VT < Inhaled VT
Aspiration is suspected
There is loss of PEEP
A decrease in cuff
pressure or volume
may be indicated
when:
Cuff pressure is >25-30
cm H2O
***Always use the lowest
inflation pressure
needed to obtain a
satisfactory seal***
Artificial Airway Management:
Tracheostomy Care
Cleaning the
tracheostomy site:
Daily
When gauze or ties
are soiled
When there are
visible secretions or
blood around the site
Replacing a
tracheostomy tube:
When plugged with
blood clot or mucus
When cuff is ruptured
When a different size
tube is indicated
Artificial Airway Management:
Tracheostomy Care
Repositioning a
tracheostomy tube is
indicated if the distal end
migrates into the
pretracheal space
–
–
–
–
Tube may be too short
Neck may be too thick
Postoperative swelling
Insecure ties
Pretracheal space
Requires emergent
reinsertion or placement
of an ETT in the stoma
http://um-jmh.org/images/healthlibrary/TRACH-1.gif
Airway Management:
Suctioning
Altering frequency or duration of
suctioning
– Suction when any of the previously listed
indications exist
– Total suction time should be < 10-15 sec.
Discontinue if bradycardia, arrhythmia,
desaturation or hypotension is induced by
suctioning
Oxygenate the patient using 100% oxygen by
resuscitator or ventilator
Airway Management:
Suctioning
Changing size of catheter
– Catheter size is determined by airway diameter; two
methods
Catheter size = ETT (mm) x 2, use the next size smaller
catheter in Fr.
Catheter size (Fr.) = ETT (mm) x 3
2
– Larger catheter will be more difficult to pass and may
occlude the airway
– Smaller catheter will not be as efficient in removing
secretions
– Once the optimal size is determined, it should not be
changed
Airway Management:
Suctioning
Changing type of catheter
Four types available
– Straight and Coudé catheters
Used when a closed-system catheter is not
available or seems ineffective
Coudé may be useful to access the left mainstem,
since it has an angled tip
– Straight and Coudé closed-system catheters
Generally used for all mechanically-ventilated
patients
Airway Management:
Suctioning
Indications for closed suction systems
– High ventilator requirements
PEEP > 10 cm H2O
MAP > 20 cm H2O
TI > 1.5 sec.
FiO2 > 0.6
– Suctioning > 6times/day
– Hemodynamic instability associated with
ventilator disconnection
– Ventilated patients with active TB
– Nitric oxide or heliox in use
Airway Management:
Suctioning
Negative pressures for suctioning
– Adult: 100-120 mm Hg
– Child: 80-100 mm Hg
– Infant: 60-80 mm Hg
If secretions are too thick to suction at the
top of any negative pressure range
– Evaluate effectiveness of humidifier
– Consider instilling solution (see below)
Do not exceed recommended ranges
Airway Management:
Suctioning
Use of irrigating solutions
– Routine use is not recommended
– Efficacy of saline remains unclear; may make the
airway and mucus “slipperier”
– Instillates may increase nosocomial infection by
washing bacteria from the airway wall into the
trachea; have been demonstrated to cause
desaturation
– Instillates have included 3-5 mL normal saline, 2%
NaHCO3, and 10% acetylcysteine; the latter two being
mucolytics
NO proven value!
Artificial Airway Management
References
Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed.
St. Louis, Mosby; 2004:655-659,681-685,
686-688.
Bronchial Hygiene
Question 1
Bronchoscopy has revealed mucus plugging of the right
lower lobe bronchus in a patient with pneumonia who is
receiving mechanical ventilation. Chest physical therapy
is ongoing while the patient is lying on his right side in
Trendelenberg. What is the therapist’s most appropriate
action?
A. Place the patient on his left side in Trendelenberg and
continue chest physical therapy.
B. Increase the frequency of suctioning.
C. Instill 3-5 mL of 10% acetylcysteine and suction.
D. Select a Coudé suction catheter and continue
suctioning.
Bronchial Hygiene
Question 2
A patient with cystic fibrosis is receiving vibratory PEP
therapy. After three secretion mobilization breaths,
several secretion elimination breaths fail to produce any
secretions. The therapist should:
A. suggest postural drainage and percussion.
B. have the patient take 8-10 secretion mobilization
breaths.
C. suction the patient.
D. administer an aerosol with 5 mL of 10%
acetylcysteine.
Bronchial Hygiene
Question 3
A patient is receiving mechanical ventilation through a
hygroscopic condenser HME. Secretions are tenacious.
There is continuous bubbling in the water seal chamber
of the pleural drainage system. The therapist should:
A. install a new hygroscopic condenser HME.
B. install a hydrophobic condenser HME.
C. instill 3 mL of 10% acetylcysteine and suction.
D. replace the HME with a heated humidifier.
Bronchial Hygiene
Question 4
A patient is receiving mechanical ventilation in the PCV mode with 15
cm H2O above PEEP. Tidal volumes measured over the past 90
minutes are as follows:
1:00pm 450 mL
1:30pm 425 mL
2:00pm 415 mL
2:30pm 405 mL
The therapist palpates an increase in rhonchial fremitus. The therapist
should:
A. increase the PCV level to achieve a tidal volume of 450 mL.
B. switch to volume controlled ventilation with a VT of 450 mL.
C. suction the patient.
D. check the ventilator circuit for leaks.
Bronchial Hygiene
Question 5
A patient’s endotracheal tube cuff pressure is 30
cm H2O. The therapist determines that the seal
is satisfactory with a pressure of 15 cm H2O.
The therapist should:
A. maintain a 30 cm H2O cuff pressure.
B. maintain the cuff at minimal leak.
C. increase cuff pressure to 34 cm H2O.
D. set the cuff pressure at 15 cm H2O.
Bronchial Hygiene
Question 6
A patient is receiving mechanical ventilation through a
tracheostomy tube. A leak is detected and the cuff will
not seal with injection of additional air. The therapist’s
most appropriate action is to:
A. replace the tracheostomy tube.
B. pack additional gauze into the stoma around the tube.
C. clean around the tube and stoma with hydrogen
peroxide.
D. insert an endotracheal tube in the stoma.
Bronchial Hygiene
Question 7
An adult with an 8mm ID endotracheal tube is being
suctioned through a 10 fr. catheter at -100 mm Hg.
However, the thick secretions are not being effectively
aspirated into the catheter. The therapist should:
A. instill 3 mL normal saline and increase suction
pressure to -140 mm Hg.
B. increase suction pressure to -120 mm Hg and
suction catheter size to 14 fr.
C. increase suction catheter size to 16 fr. And maintain
-100 mm Hg suction
D. instill 3 mL normal saline and continue suctioning.
Bronchial Hygiene
Question 8
An adult with an 8 mm ID tracheostomy tube is being suctioned with a
14 fr. Catheter at -120 mm Hg. Secretions are thick and are not
being aspirated effectively. Which of the following should the
therapist consider?
I. Increasing the airway temperature
II. Installing an HME
III. Instilling normal saline before suctioning
IV. Increasing the size of the suction catheter
A. I, II only
B. II, III only
C. I, III only
D. II, IV only
Bronchial Hygiene
Key
1. A
2. B
3. D
4. C
5. D
6. A
7. B
8. C
Bronchial Hygiene
Question 1 analysis
Answer A is correct because it alters the
patient’s position to addresses the issue of
mucus plugging in the right lower lobe.
More frequent suctioning may help. The
undirected instillation of acetylcysteine
down the trachea has little or no effect. A
Coudé suction catheter may be useful
when one wants to suction the left lung.
Bronchial Hygiene
Question 2 analysis
Answer B is correct. When using the Flutter
or AcapellaTM, 8-10 secretion mobilization
breaths precede secretion elimination
breaths. If the patient uses these devices
as directed, CPT and suctioning should be
unnecessary. There is no documentation
that aerosolized acetylcysteine is useful
for any pulmonary condition.
Bronchial Hygiene
Question 3 analysis
Since secretions are tenacious and there is
bubbling in the water seal chamber
(indicating that exhaled VT is < inhaled VT),
any HME is contraindicated. Therefore, D,
a heated humidifier, should be used in
place of the HME. Instilled acetylcysteine
would be hazardous and make no
difference.
Bronchial Hygiene
Question 4 analysis
Since the tidal volume is decreasing, there must be
an increase in resistance. This is confirmed by
the increased fremitus which indicates
secretions. The answer is C, suction the patient.
Increasing the pressure or changing to VCV
could expose the patient to excessive pressure
and would not correct the problem. If there was
a leak, the ventilator would likely be time cycling
and there would be an alarm.
Bronchial Hygiene
Question 5 analysis
Always use the lowest inflation pressure
needed to obtain a satisfactory seal.
Therefore, D is the correct answer. Cuff
pressure could be set to minimal leak,
minimal seal, 30 or 34 cm H2O, but any of
these may cause tracheal damage
eventually.
Bronchial Hygiene
Question 6 analysis
There is a leak in the cuff or in the pilot
balloon line. The best fix is to replace the
tube (A). There should always be a spare
nearby. Cleaning and packing the tube
does nothing in this case. Inserting an
endotracheal tube in the stoma will restore
ventilation, but is not the optimal
procedure.
Bronchial Hygiene
Question 7 analysis
Both the suction catheter size and vacuum
pressure are inadequate and should be
increased (B). Instillation of saline may
help. An 18 fr. catheter is too big for an 8
mm airway.
Bronchial Hygiene
Question 8 analysis
Increasing the gas temperature at the airway
is correct, since the humidifier will provide
more water vapor. Instilling saline may
help my making secretions slipperier,
which may help temporarily. An HME is
contraindicated in the presence of thick
secretions and the correct size catheter is
already in use.
Section 6: IIIF9 Mechanical
Ventilation
Monitoring and adjusting alarm settings
– Volume
– Pressure
– Incompatible settings
– FiO2
– Temperature
– Apnea
Mechanical dead space
– A “dead” issue
– No longer used or recognized
Monitoring and Adjusting Alarm
Settings
Low exhaled tidal volume
– Set 100 mL or 10-15%% below set VT
Low exhaled minute volume
– 2-5 L/min. or 10-15% below baseline VE
Alerts personnel to the presence of a leak
If VT or VE change or are changed appropriately,
alarm tolerances should be adjusted accordingly
When a volume alarm sounds, the patient
should be manually ventilated until mechanical
ventilation can be restored
Monitoring and Adjusting Alarm
Settings
High exhaled minute volume
– Set to 5L/minute or 10-15% above baseline minute
volume
– High volume alarm indicates tachypnea and/or
hyperpnea and some level of patient distress
– May indicate the patient is trying to meet metabolic
demands by increasing ventilation (i.e.
sepsis/metabolic acidosis)
– May indicate patient discomfort or anxiety
– If VE changes or is changed appropriately, alarm
tolerances should be adjusted accordingly
Monitoring and Adjusting Alarm
Settings
Low [peak] pressure
– Set to 8 cm H2O or 5-10 cm H2O below PEEP
– Indicates loss of pressure during inspiration
– Usual cause is a leak at any circuit
connection, at the endotracheal tube cuff, or
in the humidifier
– If tidal volume is adjusted in VC modes or
pressure is adjusted in PC modes, the low
pressure tolerance is adjusted accordingly.
Monitoring and Adjusting Alarm
Settings
Low PEEP
– Set to 3-5 cm H2O below PEEP
– Some ventilators will attempt to compensate for this
by increasing flow
– Any condition causing a leak, leading to a low peak
pressure alarm, may lead to a low PEEP alarm
– As PEEP is changed, the low PEEP alarm is adjusted
accordingly
– In the event of a low pressure or PEEP alarm, manual
ventilation is provided until the fault is corrected
Monitoring and Adjusting Alarm
Settings
High pressure limit
– Set to 50 cm H2O initially, then 10-12 cm H2O above
PIP once PIP is established
– Indicates an obstruction in the circuit, decreasing
compliance, or increasing resistance
Secretions, tube kink, coughing
– In the event of repeated high pressure alarms, the
patient should be manually ventilated while the cause
is determined and remedied
– If tidal volume or PIP are changed appropriately, then
the high pressure limit is adjusted accordingly
Monitoring and Adjusting Alarm
Settings
Incompatible settings
– Part of the ventilator’s logic to prevent an
inverse I:E ratio
– Automatic, alerts the therapist to the
incompatibility of requested settings and
suggests an action
– Example: the therapist sets a flow of 30
L/minute and a mandatory rate of 24
breaths/minute with a tidal volume of 800 mL.
– This results in an inverse I:E, and a message
suggesting an increase in flow
Monitoring and Adjusting Alarm
Settings
FiO2
– Ventilators that incorporate an oxygen
analyzer may allow the therapist to set high
and low limits
– Set to 5-10% above and below the desired
FiO2
– If FiO2 is changed, the therapist adjusts the
FiO2 limits accordingly
Monitoring and Adjusting Alarm
Settings
Temperature
– Set 2°C above and below set temperature at the
airway
– Some humidifiers allow this setting, for others it is
automatic
– Alerts the therapist if there is excess/loss of heat at
the airway
– Usually the result of a faulty heater, circuit wire,
thermistor wire, or entire heater, usually requiring
replacement of the wire at fault
– In this event, it may be appropriate to place an HME
until the problem is resolved
Monitoring and Adjusting Alarm
Settings
Apnea
– Alerts the therapist of apnea in spontaneous
breathing modes or low-rate IMV
– Set to a value < mandatory total cycle time or
20 seconds
– Frequent apnea alarms may indicate loss of
ventilatory drive or oversedation and require
an increase in mandatory rate
Mechanical Dead Space
A length of ventilator circuit tubing inserted
between the circuit Y and the endotracheal tube
Provides for a measured amount of rebreathed
volume in each breath equal to 50 mL/6” length
of tubing inserted
Used to normalize/increase a patient’s PaCO2
and decreased pH when a high minute volume is
used
No contemporary use of mechanical dead
space, no reference in contemporary texts
There are no written recommendations on
changing mechanical dead space
Mechanical Ventilation
Reference
Wilkins RL, Stoller JK, Scanlan CL. Egan’s
Fundamentals of Respiratory Care, 8th ed.
St. Louis, Mosby; 2004:1031-1032.
Mechanical Ventilation
Question 1
A patient is receiving volume controlled ventilation.
It is agreed that the patient’s ARDS is
worsening. Ventilatory parameters are not being
changed at this time. Which of the following
adjustments may be required?
A.
B.
C.
D.
increase the pressure limit
increase the minute volume limit
decrease the apnea interval
decrease the tidal volume limit
Mechanical Ventilation
Question 2
A patient with COPD is receiving volume controlled
ventilation. A bronchodilator treatment has
provided significant relief from bronchospasm.
An alarm sounds frequently after the treatment.
The therapist will likely:
A. increase the high pressure alarm limit
B. decrease the minute volume limit
C. increase the tidal volume alarm limit
D. decrease the low pressure alarm limit
Mechanical Ventilation
Question 3
A patient awakens following coronary artery
bypass grafting, and is receiving volume
controlled ventilation. He appears restless and
an alarm sounds on his ventilator. The therapist
is most likely to:
A. increase the high pressure alarm limit.
B. increase the minute volume limit.
C. decrease the tidal volume alarm limit.
D. decrease the low pressure alarm limit.
Mechanical Ventilation
Question 4
A postoperative patient is receiving pressure
support ventilation during the weaning process.
After receiving medication for pain, an alarm
sounds. The therapist will most likely have to:
A. increase the high pressure alarm limit.
B. increase the minute volume limit.
C. decrease the low tidal volume alarm limit.
D. decrease the low pressure alarm limit.
Mechanical Ventilation
Key
1. A
2. D
3. B
4. C
Mechanical Ventilation
Question 1 analysis
Worsening or ARDS is characterized by a
decrease in compliance. At a fixed tidal
volume, this means that peak pressure will
increase. The pressure limit will sound,
indicating a limiting of both pressure and
volume. For the patient to receive the
same volume, the pressure limit will have
to be increased, so the answer is A.
Mechanical Ventilation
Question 2 analysis
Whenever bronchospasm is relieved,
resistance decreases and so does peak
pressure. If the peak pressure decreases
below the previously set low pressure
alarm limit, that alarm will sound. This
necessitates a decrease in the low
pressure alarm setting. The answer is D.
Mechanical Ventilation
Question 3 analysis
When a patient awakens and is receiving
mechanical ventilation, it is likely that he will be
restless, or at least, move around some and
increase his ventilation. Therefore, the minute
ventilation should increase, which may result in
a high minute ventilation alarm. Therefore, the
therapist may have to increase the minute
ventilation limit. The answer is B.
Mechanical Ventilation
Question 4 analysis
When a patient receives a pain medication,
ventilatory drive may be decreased, which, in
PSV, may decrease tidal volume or minute
ventilation. In this case, the tidal volume has
likely decreased, which will trigger the low tidal
volume alarm. The therapist will have to adjust
the low tidal volume alarm and consider if it is
necessary to implement a mandatory rate until
the sedation has metabolized. C is correct.