Test 1 Flashcards

(372 cards)

1
Q

Define NIV.

A

The delivery of mechanical ventilation to the lungs using techniques that don’t require an endotracheal airway.

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2
Q

What are the three basic methods of applying NIV?

A
  1. Negative-pressure ventilation
  2. Positive-pressure ventilation
  3. Abdominal-displacement ventilation
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3
Q

Explain how negative pressure ventilators work.

A

The negative pressure is transmitted across the chest wall, into the pleural space, and into the intraalveolar space. Resulting in an increase in transpulmonary pressure causing air to enter the lungs.

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4
Q

List the clinical benefits of NIV in the chronic care setting. (4)

A
  • Prolongs survival
  • Improves duration and quality of sleep
  • Alleviates symptoms of chronic hypoventilation
  • Improves functional capacity
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5
Q

List 5 symptoms of chronic hypoventilation.

A
  • Fatigue
  • Morning headache
  • Daytime hypersomnolence
  • Cognitive dysfunction
  • Dyspnea
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6
Q

What clinical indicators demonstrate improvement in patient comfort?

A
  • Decreased respiratory rate
  • Reduced inspiratory muscle activity
  • Synchronization with the ventilator
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7
Q

What tidal volume range should be used with NIV and how is it manipulated?

A

5-7 mL/kg or greater. Volume is manipulated by increasing the difference between IPAP and EPAP. This is usually accomplished by increasing the IPAP.

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8
Q

What are the typical ranges for the inspiratory and expiratory settings on the BiPAP?

A
  • IPAP: 2-30 cm H2O
  • EPAP: 2-20 cm H2O
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9
Q

What role does NIV play in “end of life” situations?

A
  • May relieve dyspnea
  • Reduce sedation requirement
  • Preserve patient comfort.
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10
Q

List four clinical disorders that manifest in chronic respiratory failure and require NIV as supportive therapy.

A
  • Acute exacerbation of COPD
  • Hypoxemic respiratory failure
  • Community-acquired pneumonia
  • Cardiogenic pulmonary edema
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11
Q

Describe how the use of NIV in the acute respiratory failure improves gas exchange.

A

By resting respiratory muscles and increasing alveolar ventilation.

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12
Q

What are some clinical benefits of NIV in the acute care setting? (7)

A
  • Reduces need for endotracheal intubation
  • Reduces incidence of VAP
  • Shortens stay in the ICU
  • Reduces mortality
  • Improves patient comfort
  • Reduces need for sedation
  • Preserves physiological airway defenses
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13
Q

What is the physiological goal of NIV in ARF?

A

Improve gas exchange by resting respiratory muscles and increasing alveolar ventilation.

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14
Q

Invasive ventilation has been shown to be an effective and often necessary method to support alveolar ventilation; however, there are associated risks that can often result in ________________.

A
  • Increased mortality and morbidity
  • Higher financial cost
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15
Q

Use of negative pressure ventilators peaked during a world wide _____________ that peaked in the 1950s.

A

Polio epidemic

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16
Q

Negative pressure ventilators are also known as ________________.

A

Body ventilators

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17
Q

Negative pressure ventilators operated on the principle of _________________.

A

Increasing lung volumes by intermittently applying negative pressure to the entire body below the neck or just to the upper region of the chest. Exhalation is passive and depends on the elastic recoil of the lungs and chest wall.

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18
Q

The first successful negative pressure ventilator is commonly referred as the ____________.

A

Iron lung

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19
Q

Exclusion criteria for NIV (8)

A

- Hemodynamic instability
- Excessive secretions
- Agitated or confused patients
- Inability to protect airway
- Brain injury with unstable respiratory drive
- Uncooperative or unmotivated patients
- Facial deformities
- Respiratory arrest or the need for immediate intubation

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20
Q

Pressure targeted ventilators are __________-limited, ____________-triggered and ___________-cycled ventilators.

A
  1. pressure-limited
  2. flow and time-triggered
  3. time-cycled
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21
Q

What is shown to be effective in the treatment of acute cardiogenic pulmonary edema (ACPE)?

A
  • Bilevel NIV
  • CPAP
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22
Q

What were some cons of the negative pressure ventilators?

A
  • Lack of portability
  • Difficulty in providing routine nursing care
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23
Q

What form of positive pressure ventilation is known to be effective in the treatment of obstructive sleep apnea?

A

CPAP

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24
Q

____________ is considered by most clinicians to be a lifesaving application of ARF.

A

Noninvasive ventilation

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25
Endotracheal intubation is associated with complications such as what? (4)
- Airway trauma - Increased risk for aspiration - VAP - Patient discomfort, typically requiring the use of sedatives **Such complications can lead to a longer hospital stay, higher mortality rate and increased healthcare costs.**
26
What is the primary goal of NIV in the acute care setting?
Avoid the need for endotracheal intubation and invasive ventilation.
27
Pressure support facilitates inspiration, thus ________________.
Increasing the tidal volume
28
NIV reduces diaphragmatic pressure swings, which suggest that ________________.
The respiratory muscles are being rested.
29
When PEEP is applied during PSV, PEEP helps _______________, thereby reducing the work required to initiate inspiration.
Offset auto-PEEP
30
Resting of the respiratory muscles and improved VT lead to what? (3)
- Lower PaCO2 - Better oxygenation - Decreased respiratory rates
31
During an acute exacerbation of COPD, increased airway resistance and an increased respiratory rate lead to what?
Hyperinflation, development of auto-PEEP (air trapping) and alveolar hypoventilation.
32
What are some conventional medical therapies used COPDs that have an acute exacerbation?
- Bronchodilators - Antiinflammatory agents - Antibiotics - Supplemental oxygen
33
In **chronic** respiratory failure, NIV is considered to be a ________________ rather than a lifesaving treatment.
Supportive therapy
34
Which was the first group of patients to be successfully converted from invasive ventilation to NIV?
Patients with neuromuscular disorders
35
Several disorders associated with nocturnal hypoventilation include: (4)
- CSA - Obesity hypoventilation syndrome - OSA combined with COPD - CHF **These disorders may lead to daytime CO2 reention**
36
If OSA continue to experience hypoventilation and nocturnal desaturation, what is typically indicated next?
NIV
37
The first step in establishing the need for ventilatory assistance is based on what clinical and blood gas criteria?
- P/F ratio less than 200 - pH less than 7.35, CO2 greater than 45 - tachypnea - use of accessory muscles - paradoxical breathing
38
Indications for NIV (9)
- Acute exacerbation of COPD - Acute asthma - Hypoxemic respiratory failure - Community-acquired pneumonia - Cardiogenic pulmonary edema - Immunocompromised patients - Postoperative patients - Postextubation - "Do not intubate"
39
What mode is this? Patient breaths spontaneously at a set **baseline pressure.**
CPAP mode
40
Pressure-targeted ventilators (PVTs) are designed to increase minute ventilation and improve gas-exchange capabilities by ________________.
Using the delivery of an IPAP and EPAP.
41
What does the patient control in CPAP mode?
Rate and depth of breathing
42
With pressure support ventilation, the difference between the two pressure levels determines _________________________.
The level of pressure support for each assisted breath
43
A change to the set IPAP only occurs when?
In response to the patient's inspiratory effort
44
What does the clinician set for S/T mode (older models may use the term A/C)? (3)
- IPAP and EPAP - Respiratory rate - Inspiratory time
45
In **all modes,** the patient's delivered VT depends on what? (4)
- The gradient between the IPAP and EPAP level - inspiratory time - patient inspiratory effort - patient's lung characteristics (airway resistance and lung compliance)
46
Average volume-assured pressure support devices automatically adapt pressure support to match a patient's ventilatory need by doing what?
Delivering an average tidal volume **based on the patient's condition.**
47
To prevent CO2 rebreathing, EPAP level should be set at ______________ so adequate gas exchange can flush CO2 from the breathing circuit.
4 cmH2o or **higher**
48
What are the two most common disadvantages of the nasal mask?
1. Air leaks 2. Skin irritation
49
The most significant disadvantage of using acute care ventilators is _________________.
The inability of some machines to compensate for leaks.
50
What does BiPAP help manage?
Oxygenation (O2) Ventilation (CO2)
51
What does CPAP help with?
Oxygenation only
52
On a BiPAP, what controls the CO2?
IPAP (VT/PIP)
53
On a BiPAP, what controls the O2?
EPAP (PEEP)
54
How do you increase O2 on BiPAP?
Increase EPAP
55
How do you decrease O2 on BiPAP?
Decrease EPAP
56
How do you correct a high CO2 on BiPAP?
Increase IPAP to blow of CO2
57
How do you correct a low CO2 on BiPAP?
Decrease IPAP to retain CO2
58
If you're adjusting a patient's mask and its not correcting a leak issue, what is likely the problem?
Wrong size
59
How do you increase oxygenation on CPAP?
- Increase FiO2 and pressure (PEEP)
60
Inspiratory time is determined by what? (4)
- Pressure setting - Flow rate - Lung compliance - Airway resistance
61
**Decreased** compliance ____________ volume. Increase or decrease?
Decreases
62
**Increased** compliance ____________ volume. Increase or decrease?
Increases
63
**Decreased** airway resistance ____________ volume. Increase or decrease?
Increases
64
**Increased** airway resistance ____________ volume. Increase or decrease?
Decreases
65
What happens if you increase the sensitivity dial?
It will make the machine less sensitive to patient inspiratory trigger.
66
What happens if the patient effort dial is set too low?
May cause auto-triggering.
67
For negative pressure ventilators, exhalation was passive and dependent on _________________________.
The elastic recoil of the lung and chest wall
68
The iron lung was designed in 1928 by who?
Phillip Drinker and Dr. Charles McKhann
69
Caution should be used when non-COPD patients with pneumonia are treated with NIV.
Something to know.
70
What is the recommendation for treating acute cardiogenic pulmonary edema?
CPAP (10-12 cmH2O). NIV should be used in patients who continue to be hypercapnic and dyspneic thereafter.
71
_________________ can have certain clinical benefits for patients with chronic hypoventilation disorders.
Nocturnal use of NIV (4-6 hours)
72
What is the argument against using NIV on DNI patients?
Prolongs dying process, adds to patient discomfort and consumes valuable resources.
73
In the acute care setting, the selection process for NIV is based on what? (3)
Patient's diagnosis, clinical characteristics and the risk for failure
74
**Portable homecare** pressure-targeted ventilators are ____________-controlled ventilators.
Micropressor-controlled, electrically powered units that use a blower to regulate gas flow into the patient circuit.
75
Explain S/T mode.
The patient may initiate breaths that are supported to the IPAP level, but if patient fails to make inspiratory effort within a set interval, machine triggers inspiration to the set IPAP level.
76
The highest pressure recorded at the end of inspiration is called:
Peak Inspiratory Pressure or Peak Airway Pressure, Peak pressure
77
Normally, two types of forces oppose inflation of the lungs. What are they called?
- Elastic forces - Frictional forces
78
_______________ is a measurement of the frictional forces that must be overcome during breathing.
Resistance
79
Airway resistance is increased or decreased when an artificial airway is inserted?
Increased
80
The product of compliance and resistance is called a _______________.
Time constant
81
For air to flow through a tube or an airway, what must exist?
Pressure gradient
82
Transrespiratory pressure has two components. What are they?
- Transthoracic pressure - Transairway pressure
83
The primary variable the ventilator adjusts to achieve inspiration is called the ________________.
Control variable
84
What are the most commonly used control variables?
Pressure and volume
85
What are some predictors of success with NIV? (8)
- Higher level of consciousness - Younger age - Less severe illness; no comorbidities - Less severe gas exchange abnormalities - Intact dentition **- Minimal air leakage around the interface** - Lower quantity of secretions - Absence of pneumonia
86
What may be the most significant indicator of success or failure to NIV?
Patient's initial response to NIV
87
Duration of ventilatory assistance depends on what?
How quickly the cause of respiratory failure can be reversed.
88
What is the ventilator mode of choice for chronic respiratory failure caused by restrictive thoracic disorders in patients who can protect their airway?
NIV
89
NIV increases VT, reduces diaphragmatic activity and improves oxygen in some patients with CF who have _______________.
Acute exacerbations
90
The therapy of choice for OSA is CPAP, but if the patient continues to hypoventilate despite CPAP therapy, what may improve daytime gas exchange and symptoms associated with chronic hypoventilation?
NIV
91
What provides a viable weaning alternative for patients who demonstrate respiratory muscle fatigue postextubation?
NIV
92
What type of patients are not viewed as good candidates for ET intubation and mechanical ventilation?
DNI patients, patients with terminal and advanced disease who develop ARF.
93
**Chart 19.1 - Pg. 360** What are symptoms indicating the need for NIV? (4)
- Moderate to severe dyspnea - RR greater than 24 breaths/min - Accessory muscle use - Paradoxical breathing
94
NIV may be unnecessary for patients with ________ respiratory distress.
Mild Also not appropriate for patients who have already deteriorated to severe respiratory failure because it may delay lifesaving intubation and ventilation.
95
____________________ MUST be considered before NIV initiated.
Reversibility of the disease process
96
___________________ involves the exchange of oxygen and carbon dioxide between an organism and its environment
Respiration
97
___________________________ is the pressure difference the alveolar space and the pleural space. **REMEMBER THERE ARE TWO NAMES**
Transpulmonary pressure or transalveolar pressure
98
_______________________ is the pressure difference between the airway opening (mouth) and the alveolus .
Transairway pressure
99
____________________________ is the pressure difference between the alveolar space or lung and the body's surface.
Transthoracic pressure
100
______________________ is the pressure in the potential space between the parietal and visceral space.
Intrapleural pressure
101
Airway opening pressure is most often called __________________________ or __________________________.
Mouth pressure or airway pressure
102
_________________________ represents the pressure required to expand or contract the lungs and the chest wall at the same time.
Transthoracic pressure
103
___________________________ is the pressure gradient required to produce airflow in the conductive airways.
Transairway pressure
104
______________________ is the pressure difference between the airway opening and the body surface.
Transrespiratory pressure
105
What two parameters are often used to describe the mechanical properties of the respiratory system and the elastic and frictional forces opposing lung inflation?
Compliance and elastance
106
One time constant should allow approximately what percentage of a lung to fill?
63%
107
Plateau pressure is used as a measure of _______________________.
Alveolar pressure
108
Air can be trapped in the lungs during mechanical ventilation if not enough time is allowed for exhalation. What is the most effective way to prevent this?
Monitor the pressure in the ventilator circuit at the end of exhalation.
109
When is plateau pressure measured?
End inspiration
110
Plateau pressure is similar to what?
Holding a breath at the end of inspiration
111
How do you obtain plateau pressure measurements?
By selecting a control marked "inflation hold" or "inspiratory pause"
112
Airway pressures are measured relative to a _______________________.
Baseline value
113
When PEEP is set, the ventilator prevents the patient from ________________________.
Exhaling to zero
114
PEEP applied by the operator is referred to as _____________________.
Extrinsic PEEP
115
PEEP and CPAP increases functional residual capacity. T or F?
True
116
What is auto-PEEP?
A potential side effect of PEEP, when air gets accidentally trapped in the lung.
117
When does intrinsic PEEP occur?
When a patient does not have enough time to exhale completely before the ventilator delivers another breath
118
High-frequency uses ______________ ventilating rates and _____________________ ventilating volumes.
- above normal ventilating rates - below normal ventilating volumes
119
Positive pressure ventilation occurs when _________________________________________.
a mechanical ventilator is used to deliver air into the patient's lungs by way of an endotracheal tube or positive pressure mask.
120
____________ time constants should be considered for I-time, particularly in pressure ventilation, to ensure adequate volume delivery.
Five
121
What happens if I-time is too long?
RR may be too low to achieve minute ventilation.
122
An expiratory time of less than _____ time constants may lead to incomplete emptying of the lungs.
3 This can increase FRC and causing air trapping in the lungs.
123
Define time constant.
The amount of time (in seconds) required for the lungs to inflate/deflate to a certain percentage of their volume
124
One time constant equals the amount of time it takes for ______% of the volume to be inhaled.
1 - 63% 2 - 86% 3 - 95% 4 - 98%
125
What are normal resistance values for intubated patients?
Approximately 6 cm H2O or higher
126
What are normal resistance values for unintubated patients?
0.6 to 2.4 cmH2O/(L/s) at 0.5 L/s flow.
127
Intrapleural pressure is usually about _____________ at the end of expiration during spontaneous breathing.
-5 cmH2O
128
What are some other names for airway opening pressure? (5)
- Mouth pressure - Airway pressure - Upper airway pressure - Mask pressure - Proximal airway pressure
129
_______________ is the pressure required to maintain alveolar inflation and is therefore sometimes called the **alveolar distending pressure.**
Transpulmonary pressure
130
The resistance to airflow depends on what? (4)
- Viscosity of the gas - Gas density - Length and diameter of the tube - Flow rate of gas through the tube
131
The diameter of the airway lumen and flow of gas can decrease as a result of: (4)
- Bronchospasm - Increased secretions - Mucosal edema - Kinks in the tube
132
The tendency of a structure to return to its original shape after being stretched or acted on by an outside force.
Elastance
133
What does increasing pressure do the I-time?
Increases
134
What does increasing flow do the inspiratory time?
Decreases
135
Increased compliance and decreased airflow resistance _______________ volume.
Increases
136
What happens if you decrease "patient effort dial" on a ventilator?
Makes the machine more sensitive. Can cause auto-triggering.
137
What is considered normal PaCO2 range for COPD patients?
50-60 mmHg
138
Decreasing the VT = _____________ PaCO2
Increased **- Decreases minute ventilation - Decreases alveolar ventilation**
139
Increasing the VT = ______________ PaCO2
Decreased **- Increases alveolar ventilation - Increases minute ventilation**
140
What manipulations would you make on a ventilator for a patient with a closed head injury? Why?
Increased RR. Hyperventilation reduces the blood flow to the brain which in turn, minimizes further swelling.
141
________________ is perhaps the single most important function a ventilator accomplishes.
Delivery of an inspiratory volume
142
What two factors determine the way the inspiratory volume is delivered?
The structural design of the ventilator and the mode set by the clinician
143
With time controller, what changes and what remains constant?
- Time remains constant - Pressure, volume and flow curves changes as lung characteristics change.
144
Flow controller: What changes, what remains constant?
- Volume delivery and flow waveform remain constant and not affected by changes in lung characteristics. - Flow is measured. - Pressure waveform varies
145
Volume controller: What changes, what remains constant?
- Ventilator volume delivery and volume waveform remain constant and not affected by lung characteristic changes. - Volume is measured. - Volume and flow waveforms are unchanged - Pressure waveform varies
146
Pressure controller: What changes, what remains constant?
- Vent maintains same pressure waveform at the mouth regardless of lung characteristic changes. - Volume and flow vary with compliance and resistance changes.
147
When the vent maintains the pressure waveform in a specific pattern, the breathing is described as __________________.
Pressure-controlled
148
T or F. Inflation hold increases I-time.
True
149
What is the most common cycling mechanism in the pressure support mode?
Flow cycling
150
What are the two most common patient-triggering variables?
Pressure and flow
151
What are the two primary control variables?
Pressure and volume
152
PEEP is defined as _____________________.
Positive pressure at the end of exhalation during either spontaneous breathing or mechanical ventilation.
153
An end-expiratory pressure is impossible to obtain if ______________________.
The patient is breathing spontaneously.
154
The pressure level from which breath begins is called the _______________________.
Baseline pressure
155
If a patient is in distress, what type of mask would you switch them to?
FULL FACE MASK
156
Ramp allows positive pressure to _________________.
Increase gradually over a set interval
157
What is the corrective action for this complication that is associated with Mask CPAP/NIV therapy? **Hypotension**
Avoid excessively high peak pressures. (<20 cmH2O)
158
What is the corrective action for this complication that is associated with Mask CPAP/NIV therapy? **Mucous plugging**
- Ensure adequate hydration - Adequate humidification - Avoid excessive O2 flow rates
159
What is the corrective action for this complication that is associated with Mask CPAP/NIV therapy? **Aspiration**
Adhere to proper selection of patients who can protect their own airway.
160
What is the corrective action for this complication that is associated with Mask CPAP/NIV therapy? **Aerophagia, gastric distention**
Use lowest effective pressures for adequate VT delivery
161
What is the corrective action for this complication that is associated with Mask CPAP/NIV therapy? **Pressure sores**
Use wound-care dressing over nasal bridge
162
What is the corrective action for this complication that is associated with Mask CPAP/NIV therapy? **Excessive leaks around mask**
- Minimize headgear tension - Switch mask style
163
What is the corrective action for this complication that is associated with Mask CPAP/NIV therapy? **Nasal/oral dryness or nasal congestion**
- Add or increase humidification - Irrigate nasal passages with saline - Apply topical decongestants - Use a chin-strap to keep mouth closed
164
What is the most common complication of NIV?
Mask discomfort
165
What can alleviate pressure on the nasal bridge and protect the skin during NIV?
Forehead spacers, wound-care dressing Nasal pillows or nasal seals
166
________________ affect delivery and response to bronchodilator during NIV.
Ventilator settings High PIP - greater deposition Increased expiratory pressure - decreased delivery in aerosol delivery
167
How long after you put a patient on NIV should you get a blood gas?
1 hr
168
Which of the following mechanical ventilation techniques mimic pursed-lip breathing and has been used to prolong the expiratory phase of spontaneously breathing individuals with a disease that leads to early airway closure?
Setting a high pressure limit
169
IPPB is _____________ triggered and ____________ cycled.
- patient (pressure), manual or time triggered - pressure cycled (NOT FULL SUPPORT)
170
IPPB machines are ___________ powered.
Pneumatically
171
IPPB is what type of tool?
Lung expansion tool
172
What is the best position for IPPB?
Semi-Fowler's
173
Equipment needed for IPPB
- Mouthpiece or nose clip - Circuit - Tracheal adapter
174
What are some clinical situations contraindicating IPPB? (9)
- Tension pneumothorax - Active hemoptysis - Tracheoesophageal fistula - Singultus - Nausea - Hemodynamic instability - ICP greater than 15 mm Hg - CXR: Blebs - Recent facial, oral or skull surgery
175
What are some potential outcomes of IPPB? (6)
- Decrease or elimination of atelectasis - Improved breath sounds - Normal or improved CXR - Increased SpO2 - Increased VC - Improved inspiratory muscle performance and cough
176
State the indication for IPPB.
- Patient with pulmonary atelectasis NOT responsive to other modalities like Incentive Spirometry - Patient inability to clear secretions - Aerosol delivery to patients with ventilatory muscle weakness or fatigue
177
Gas absorption can occur when ______________________.
Mucous plugs block ventilation to selected regions of the lungs.
178
Resistance when bagging could mean what?
- Patient needs suctioning - Bronchospasm
179
What are some clinical signs of atelectasis?
- Tachypnea - Fine-late inspiratory crackles (alevoli are trying to pop open) - Increased density and signs of volume on CXR - Bronchial breath sounds
180
What are some factors associated with atelectasis? (5)
- Neuromuscular disorders - Obesity - Heavy sedation - Surgery near diaphragm - Restrictive chest wall deformities
181
What is the standard criteria for instituting mechanical ventilation? (4)
- Apnea - Acute ventilatory failure - Impending ventilatory failure - Refractory hypoxemia respiratory failure with increased WOB or an ineffective breathing pattern
182
What is the normal tidal volume for someone who is breathing spontaneously?
5-7 mL/kg
183
What are the goals of therapy for mechanically ventilated patients? (5)
1. Support the pulmonary system so it can maintain an adequate level of alveolar ventilation. 2. Reduce the WOB until the cause of respiratory failure can be idenitified and treated. 3. Restore arterial and systemic acid-base balance to levels that are normal to the patient. 4. Increase oxygen delivery to and oxygenation of body organs tissue. 5. Prevent complications associated with MV.
184
What are the initial settings for IPPB?
- Sensitivity: -1 to 2 cmH2O - Initial pressure: 10-15 cmH2O - Breathing 6-8 breaths/min (I:E ratio of 1:3 or 1:4) - Low rate to provide full expansion for lungs. - I:E ratio: 1:3 or 1:4
185
Give 2 examples HFPAP devices.
- MetaNeb - IPV (Intrapulmonary percussion ventilator)
186
NIV is typically used for ______________.
Chronic ventilatory failure
187
What is the recommended range to use on CPAP for the initial treatment of acute cardiogenic pulmonary edema?
10-12 cmH2O, to push the fluid out
188
What is the equipment generally required for NIV?
- Ventilators - Humidifiers - Interfaces or mask
189
What does pneumatically powered mean?
It needs a gas source to run
190
What does flow triggered mean?
The machine will sense what the patient is doing and it will allow the patient to trigger a breath
191
PTVs allow adjustment of the amount of time required to reach IPAP, what is this called?
Rise-time control
192
What is rise time?
The amount of time until you reach the maximum pressure or maximum volume.
193
Ramp rates can be set in increments of _______.
1, 2, 3 cmH2O
194
What type of vent has no graphic display and very basic alarms?
Portable home care ventilators.
195
Why is the passover-type heated humidifiers often used?
Heated bubble humidifier and HME can increase airway resistance in the ventilator circuit and interfere with patient triggering and increase inspiratory WOB.
196
What are the initial pressure for NIV? EPAP and IPAP.
- EPAP: 4-5 cm H2O - IPAP: 8-10 cm H2O
197
Insufficient IPAP levels often result in…..
- Sustained or increased RR caused by inadequate VT delivery
198
When is NIV terminated in favor of invasive measures? (4)
- pH and PaCO2 continues to worsen accompanied by respiratory distress - worsening level of consciousness - hemodynamic instability - worsening oxygenation
199
Complications with NIV are usually related to what? (3)
- Mask discomfort (most common) - Air pressures - Gas flow
200
Standard weaning techniques have not been established most common approach involves increasing __________________.
Periods off mask ventilation
201
Criteria for Terminating NIV and Switching to Invasive MV. (7)
- Worsening pH and PaCO2 - Tachypnea (>30 breaths/min) - Hemodynamic instability - SpO2 <90% - Decreased level of consciousness - Inability to clear secretions - Inability to tolerate interface
202
What are a few ways to increase volume?
- Increase pressure - Decrease flow
203
Hazards and Complications of IPPB (5)
- Hypoventilation and respiratory alkalosis - Discomfort secondary to inadequate pain control - Pulmonary barotrauma - Exacerbation or bronchospasm - Fatigue
204
Define tension pneumothorax.
When pressure builds up until it shifts the mediastinum. Once it’s shifted, it causes cardiac instability.
205
How long does IPPB treatments last?
15-20 minutes
206
What is the main indication for hyperinflation therapy?
To prevent or treat atelectasis
207
What type of atelectasis is this? Ventilation is compromised in a large airway or bronchus.
Lobar atelectasis
208
What type of atelectasis is this? Atelectasis that occurs when a mucous plug blocks ventilation to selected regions of the lungs. (V/Q mismatch)
Gas absorption atelectasis
209
List some side effects of opioids. (11)
- Nausea - Vomiting - Constipation - Respiratory depression - Bradycardia - Hypotension - Myoclonus - Seizures - Histamine release - Immunosuppression - Physical dependence
210
What are some common side effects associated with diACh? (7)
- Transient hyperkalemia - Cardiac dysrhythmias - Prolonged apnea **- Anaphylactic responses** **- Postoperative myalgias** - Myoglubinuria - Sustained skeletal muscle contraction
211
What are the most common reasons for using NMBAs on patients on mechanical ventilation? (6)
- Patient-ventilator asynchrony - Facilitation of intubation - Dynamic hyperinflation that cannot be corrected - Adjunctive therapy for controlling ICP - Reduction of O2 consumption and carbon dioxide production - Facilitation of less conventional MV strategies
212
What is usually prescribed to critically ill patients to treat anxiety and agitation or at least minimize sleep deprivation?
Sedatives
213
The severity of opioid side effects depends on what three things?
- Dosage administered - Extent of patient's illness - Integrity of organ function
214
Potential adverse drug interactions are less likely with lorazepam that other benzodiazepines because _____________________________________________________.
It is metabolized in the liver to inactive metabolites.
215
What are some hemodynamic effects that propofol causes?
Reduced blood pressure, bradycardia, reduces cerebral blood flow and ICP .
215
Continual use of lorazepam has been associated with several side effects including: (3)
Lactic acidosis, hyperosmolar coma and a reversible neurotoxicity
216
Fentanyl has minimal effects on the cardiovascular system and does not cause ____________________ as does morphine.
Histamine release
217
_____________________________ are used to lessen pain.
Analgesics
218
**Which of the following is a naturally occurring opioid agonist?** a. Fentanyl b. Morphine sulfate c. Precedex d. Rocuronium
b. Morphine sulfate
219
What are paralytics used for?
Paralytics are used to facilitate invasive procedures, prevent movement and ensure the stability of artificial airways.
220
_______________ are used to reduce anxiety and agitation and promote sleep and anterograde amnesia.
Sedatives
221
___________________________ is an ideal sedative when rapid awakening is important, such as when neurological assessment is required, or for extubation.
Propofol
222
Paralysis can be achieved with neuromuscular blocking agents that are classified as ______________________________________ (2) depending on their mode of action.
- Depolarizing - Nondepolarizing
223
Which of the following is the ONLY example of a depolarizing neuromuscular blocking agent (NMBA)?
Succinylcholine
224
Reversal of the effects of benzodiazepines can be accomplished with _____________________________.
Flumazenil (Romazicon)
225
Neuroleptics are routinely used to treat patients demonstrating evidence of _______________ and ______________________.
Extreme agitiation and delirium
226
Benzodiazepines have been the drugs of choice for the treatment of ___________________ in critical care.
Anxiety
227
List some adverse effects of propofol administration. (4)
- Hypotension - Dysrhythmias - Elevation of pancreatic enzymes - Bradycardia
228
What two drugs should be used for rapid sedation of acutely agitated patients?
- Midazolam - Diazepam
229
The intensity and duration of action for various benzodiazepines can be affected by a number of patient-specific factors like:
Age, underlying pathology and concurrent drug therapy
230
What is the drug of choice for sedating mechanically ventilated patients in the ICU for longer than 24 hours?
Lorazepam
231
List what drugs are classified as a Sedative (Benzodiazepines)
- Diazepam - Midazolam - Lorazepam - Chlordiazepoxide - Dexmedetomidine - Alprazolam - Triazolam - Flurazepam
231
What are some of the most common side effects of flumazenil? (3)
- Dizziness - Panic attacks - Cardiac ischemia. May lead to seizures in patients receiving long term administration.
232
______________________ produces anxiolytic, hypnotic, muscle relaxation, anticonvulsant and anterograde amnesic effects.
Benzodiazepines
233
Depolarizing agents resemble _______________________ in their chemical structure.
Acetylcholine
234
**Provide the brand name for the following.** Pancuronium
Pavulon
235
**Provide the brand name for the following.** Vecuronium
Norcuron
236
**Provide the brand name for the following.** Atracurium besylate
Tracrium
237
**Provide the brand name for the following.** Cisatracurium
Nimbex
238
**Provide the brand name for the following.** Rocuronium
Zemuron
239
**Provide the brand name for the following.** Hydromorphone
Dilaudid
240
**Provide the brand name for the following.** Flurazepam
Dalmane
241
**Provide the brand name for the following.** Triazolam
Halcion
242
**Provide the brand name for the following.** Alprazolam
Xanax
243
**Provide the brand name for the following.** Dexmedetomidine
Precedex
244
**Provide the brand name for the following.** Chlordiazepoxide
Librium
245
I:E ratio is adjusted by what ventilator controls?
- Tidal volume (VT) - Respiratory rate - Flow rate
246
Increasing (higher) flow = ______________ i-time.
Lower
247
Decreasing (lower) flow = ______________ i-time.
Increased
248
What equipment adds to mechanical dead space?
- Long ET tube - Closed system suction - HME
249
What is the VE equation?
VT x RR
250
Define anatomic dead space.
Volume lost in the patient conducting airway where NO gas exchange occurs. - trachea - bronchi
251
What manipulation would you make to the tidal volume to get a higher i-time?
Increased, higher
252
What manipulation would you make to the tidal volume to get a lower i-time?
Decreased, lower
253
What is the alveolar minute ventilation equation?
(VT-VD) x RR
254
What is the TCT equation?
60 seconds/RR
255
What is the ideal breathing pattern for a patient on IPPB?
Slow, deep breaths
256
List ways to improve oxygenation. (6)
- Increasing FiO2 - Improving ventilation - **PEEP (second)** - Pressure control with inverse ratio ventilation - Proning - APRV and Bilevel ventilation (focuses on mean airway pressure)
257
Refractory hypoxemia caused by _________________________ **does not** respond to increased FiO2.
Intrapulmonary shunting
258
What is the static compliance equation?
Cs = VT/[Pplat-EEP]
259
What is the airway resistance equation?
(PIP- Pplat)/Flow(L/s)
260
What is the dynamic compliance equation?
VT/PIP-EEP
261
Which of the following is an anesthetic that reduces cerebral blood flow and intracranial pressure, making it a useful sedative for neurosurgical patients?
Propofol
262
What should be a primary goal when administering sedatives, analgesics and NMBAs?
Maintaining an optimal level of patient comfort and safety.
263
Haloperidol possesses _____________ and ________________ effects.
Antidopiminergic and anticholinergic
264
List all of the nondepolarizing NMBAs. (5)
- Pancuronium (Pavulon) - Vecuronium (Norcuron) - Atracurium besylate (Tracrium) - Cisatracurium (Nimbex) - Rocuronium (Zemuron)
265
Is succinylcholine a short or long-acting NMBA?
Short
266
Is pancuronium bromide a short or long-acting NMBA?
Long
267
Is vecuronium bromide a short or long-acting NMBA?
Long
268
Prolonged recovery from benzodiazepines typically occurs in what type of patients?
Renal and hepatic insufficiency
269
**Provide the brand name for the following.** Midazolam
Versed
270
**Provide the brand name for the following.** Diazepam
Valium
271
**Provide the brand name for the following.** Lorazepam
Ativan
272
**Provide the brand name for the following.** Succinylcholine
Anectine
273
**Provide the brand name for the following.** Haloperidol
Haldol
274
A common method used to assess the depth of paralysis is an electronic technique referred to as ____________________________.
Train-of-four (TOF)
275
What is the opioid of choice for patients with unstable hemodynamic status and renal insufficiency?
Fentanyl
276
What is the drug of choice for sedating mechanically ventilated patients in the ICU for longer than 24 hours?
Lorazepam
277
___________________________ is a synthetic opioid that is approximately 100 to 150 times more potent than morphine.
Fentanyl
278
Which of the following is most often used to facilitate endotracheal intubation?
Anectine or succinylcholine
279
What is usually prescribed to critically ill patients to treat anxiety and agitation or at least minimize sleep deprivation?
Sedatives
280
What is the name of the single-category scale used by the clinician to determine a patient's stimuli?
Ramsay Sedation Scale
281
Benzodiazepines generally produce only minimal effect on cardiovascular function, however they can cause a significant **(increase/drop)** in blood pressure when initially administered to hemodynamically unstable patients.
Drop
282
The Joint Commission has defined four levels of sedation. List them.
- Minimal sedation - Moderate sedation (conscious patient) - Deep sedation - Anesthesia
283
Propofol is an IV, general _______________ agent that possesses sedative, amnesic and hypnotic properties at low doses, although it has **no analgesic properties.**
Anesthetic
284
What is the primary pharmacological action of opioids?
To relieve pain
285
Which of the following produces anxiolytic, hypnotic, muscle relaxation, anticonvulsant and anterograde amnesic effects?
Benzodiazepines
286
Midazolam causes a reduction in cerebral perfusion pressure but it does not protect against increases in ICP for patients receiving _______________.
Ketamine
287
__________________ is a sedative that does not affect the patient’s ventilatory drive.
Precedex, Dexmedetomidine
288
Do neuromuscular blocking agents possess sedative or analgesic properties?
No.
289
Haloperidol is a butyrophenone that causes ____________________.
CNS depression
290
Diazepam is metabolized in the ____________ to activate metabolites that have relatively long half-lives (40-100 hours).
Liver
291
______________________ are endogenous and exogenous substances that can bind to a group of receptors located in the CNS and peripheral tissues.
Opioids (Opiates)
292
Morphine is potent opioid analgesic agent that is preferred agent for intermittent therapy because of its:
Longer duration of action
293
_________________ reverses the side effects caused by opioids.
Naloxone hydrochloride (Narcan)
294
Morphine can alter vascular resistance by causing _________________ in sympathetic tone and _____________________ in vagal tone.
Decreases; Increases
294
What are some hemodynamic effects that propofol causes? (4)
Reduced blood pressure, bradycardia, reduces cerebral blood flow and ICP
295
_______________ has been shown more effective than fentanyl in reducing ICP in patients with traumatic brain injury.
Propofol
296
**Which of the following is the drug of choice for delirium?** a. Haloperidol b. Morphine c. Precedex d. Anectine
a. Haloperidol
297
What opioid is preferred for patients with hemodynamic instability and renal insufficiency?
Fentanyl
298
Prolonged use (>48 hours) of propofol has been associated with _________________________ in pediatric patients.
- Lactic acidosis - Lipidemia
299
T or F. Morphine alters the control of breathing even in normal healthy individuals.
True
300
Which benzodiazepine can produce significant reduction in systemic vascular resistance and blood pressure in patients who depend on increased sympathetic tone to maintain venous return?
Midazolam (Versed)
301
List some potential side effects of morphine. (7)
- Reductions in minute ventilation - Periodic breathing and even apnea by altering respiratory activity - Reductions of cerebral blood flow, ICP and cerebral metabolic activity - Drowsiness - Lethargy - Miosis - Suppression of the cough reflex
302
What is the Vd/Vt ratio?
PaCO2-PeCO2/PaCO2
303
What is the alveolar air equation?
PAO2= (PB-PH2O) FiO2 - PaCO2 x 1.25
304
What does APRV and Bilevel ventilation focus on?
Mean Airway Pressure
305
**Specific Treatments for Arterial Hypoxemia** What is the treatment for _Hypoventilation?_
- Increase FiO2 - Increase alveolar ventilation
306
**Specific Treatments for Arterial Hypoxemia** What is the treatment for _Low ventilation/perfusion ratio?_
- Increase FiO2 - CPAP
307
**Specific Treatments for Arterial Hypoxemia** What is the treatment for _Intrapulmonary shunt?_
- CPAP - Increase FiO2
308
**Specific Treatments for Arterial Hypoxemia** What is the treatment for _Diffusion defect?_
- CPAP - Increase FiO2
309
**Specific Treatments for Arterial Hypoxemia** What is the treatment for _Low inspired oxygen concentration (<21%?_
Increase FiO2
310
What are the initial vent settings for **normal lungs?**
**Mode:** VC- or PC-CMV **VT:** 6-8 **Rate:** 10-15 **Flow:** 60 **Flow Waveform:** Descending or constant **I-time:** 1 **PEEP:** Less than or equal to 5 **FiO2:** Less than or equal to .5
311
What are the initial vent settings for **COPD?**
**Mode:** VC- or PC-CMV **VT:** 6-8 **Rate:** 8-12 **Flow:** >60 (80-100) **Flow Waveform:** Descending or constant **I-time:** 0.6-1.2 **PEEP:** Greater than or equal to 5 or 50% of intrinsic PEEP **FiO2:** Less than .5
312
What are the initial vent settings for **Neuromuscular disorders?**
**Mode:** VC-CMV **VT:** 6-8 **Rate:** 8-12 **Flow:** > or equal 60 **Flow Waveform:** Descending or constant **I-time:** 1 **PEEP:** 5 **FiO2:** 0.21
313
What are the initial vent settings for **Asthma?**
**Mode:** VC- or PC-CMV **VT:** 6-8 **Rate:** 10-14 **Flow:** 60-70 **Flow Waveform:** Descending **I-time:** < or equal to 1 **PEEP:** Only to offset intrinsic PEEP and improve triggering **FiO2:** > or equal to .5
314
What are the initial vent settings for **Closed Head Injury?**
**Mode:** VC- or PC-CMV **VT:** 6-8 **Rate:** 15-20 **Flow:** 60 **Flow Waveform:** Descending or constant **I-time:** 1 **PEEP:** 0-5 with caution. Only in severe hypoxemia. **FiO2:** 1.0
315
What are the initial vent settings for **ARDS?**
**Mode:** VC- or PC-CMV **VT:** 4-8 **Rate:** 12-35 **Flow:** > or equal to 60 **Flow Waveform:** Descending or constant **I-time:** 1 **PEEP:** 5 to >15 **FiO2:** 1.0
316
What are the initial vent settings for **CHF?**
**Mode:** VC- or PC-CMV **VT:** 6-8 **Rate:** > or equal to 10 **Flow:** > or equal to 60 **Flow Waveform:** Descending or constant **I-time:** 1-1.5 **PEEP:** 5-10 **FiO2:** 1.0
317
Airway clearance therapy uses noninvasive techniques designed to do what?
Assist in mobilizing and removing secretions to improve gas exchange.
318
What is the primary invasive method for removing airway secretions?
Suctioning
319
Normal airway clearance requires what? (4)
- Patent airways - Functional mucociliary escalator - Adequate hydration - Effective cough
320
Mucociliary clearance normally occurs from the _______________ down to the ______________.
Mucociliary clearance normally occurs from the **larynx** down to the **respiratory bronchioles.**
321
What are the four distinct phases of a cough?
- Irritation - Inspiration - Compression - Expulsion
322
_________________ is a good example of an inflammatory process that can stimulate a cough.
**Infection** is a good example of an inflammatory process that can stimulate a cough.
323
The abnormal stimulus is normally ________________________________. (4)
The abnormal stimulus is normally **inflammatory, mechanical, chemical or thermal.**
324
___________ can provoke a cough through mechanical stimulation.
**Foreign bodies** can provoke a cough through mechanical stimulation.
325
Inhaling irritant gases (e.g., cigarette smoke) can result in coughing through _________ stimulation.
Inhaling irritant gases (e.g., cigarette smoke) can result in coughing through **chemical** stimulation.
326
What may cause thermal stimulation of sensory nerves, producing a cough?
Cold air
327
Retentions of secretions can result in __________.
Retentions of secretions can result in **full or partial airway obstruction.**
328
Full obstruction, or mucous plugging, can result in what?
Atelectasis which causes hypoxemia due to shunting.
329
A partial obstruction restricts airflow, increasing work of breathing and possibly leading to.....
A partial obstruction restricts airflow, increasing work of breathing and possibly leading to **air trapping, lung overdistention and V/Q imbalances.**
330
In the presence of pathogenic organisms, retention of secretions can also lead to _________.
In the presence of pathogenic organisms, retention of secretions can also lead to **infections.**
331
What are some causes of impaired mucociliary clearance in intubated patients? (9)
- ET tube or tracheostomy tube - Tracheobronchial suction - Inadequate humidification - High FiO2 values - Drugs - General anesthetics - Opiates - Narcotics - Underlying pulmonary disease
332
What is the primary goal of ACT?
To assist the patient to mobilize and remove retained secretions.
333
In CF, the solute concentration of the mucus is altered because of what?
Abnormal sodium and chloride transport. This alteration increases the viscosity of mucus and impairs its movement up the respiratory tract.
334
What disease process permanently damages and dilates airways that are prone to obstruction due to retained secretions?
Bronchiectasis
335
What are the most common conditions affecting the cough reflex?
Musculoskeletal and NMD, including muscular dystrophy, ALS, spinal muscular atrophy, MG, poliomyelitis and cerebral palsy.
336
What is the most common finding in CF and ciliary dyskinetic syndrome?
Bronchiectasis.
337
Removal of retained secretions may do what?
- Improve gas exchange - Promote alveolar expansion - Reduce work of breathing
338
Patients with acute conditions in whom ACT may be indicated include:
- Acutely or chronically ill patients with copious secretions - Patients with retained secretions or ineffective cough (coarse crackles, worsening oxygenation and/or ventilation, volume loss of CXR) - Possibly patients with acute lobar atelectasis - Patient with V/Q abnormalities
339
What are some indications for airway clearance therapy (acute conditions)?
- Copious secretions - Inability to mobilize secretions - Ineffective cough
340
What are some indications for airway clearance therapy (chronic conditions)?
- CF - Bronchiectasis - COPD patients with retained secretions - Ciliary dyskinetic syndromes
341
In treating chronic respiratory conditions, ________ before ACT may improve the overall effectiveness of the treatment both by opening the airways and increasing mucociliary activity.
In treating chronic respiratory conditions, **inhaled bronchodilator therapy** before ACT may improve the overall effectiveness of the treatment both by opening the airways and increasing mucociliary activity.
342
What are some acute conditions for which ACT is probably not indicated?
- Routine care of COPD - Pneumonia without clinically significant sputum production - Routine postoperative care - Uncomplicated asthma
343
Bronchodilator therapy is not indicated in the acute care setting for airway clearance therapy unless what?
Unless the patient is wheezing due to bronchospasm or has a chronic pulmonary condition with retained secretions.
344
Generally, sputum production must exceed _______ for ACT to improve secretion removal significantly.
Generally, sputum production must exceed **20-30 mL/day** for ACT to improve secretion removal significantly.
345
What does the best-documented preventive uses of ACT include?
- Body positioning and patient mobilization to prevent retained secretions in acutely ill patients - ACT combined with physical activity to maintain lung function in patients with CF.
346
What are the indications for CPT?
- Presence of copious secretions - Inability to mobilize and expectorate the secretions - Pulmonary disorders associated with retained secretions
347
The RT should identify the appropriate lobes and segments for drainage based on what two things?
- Preliminary assessment of the patient - Review of the physician’s order
348
Before positioning the patient, what should be done?
Procedure must be explained to the patient.
349
Before starting the procedure, what should be obtained?
- Vital signs - Auscultate chest - Measure SpO2
350
What should be monitored before, during and after CPT?
- Subjective responses (pain, discomfort, dyspnea, response to therapy) - Arrhythmias - Breathing pattern - Sputum production - Skin color - ICP if monitored
351
What are contraindications to the use of CPT? (11)
- Bronchopleural fistula - Distended abdomen - Lung contusion - Coagulopathy - Osteoporosis - Bronchospasm - Esophageal surgery - Pulmonary edema associated with CHF - Subcutaneous emphysema - Pacemaker - Suspected TB
352
If the ACT/PD procedure causes vigorous coughing what should you do?
Have the patient sit up until the coughing subsides.
353
What machine performance should you be monitoring with Intermittent Positive Airway Pressure Breathing Therapy?
- Sensitivity - Peak pressure - Flow setting - FiO2
354
What patient response should you be monitoring with Intermittent Positive Airway Pressure Breathing Therapy? (12)
- Expired volume - Peak flow or FEV1/FVC - Pulse rate and rhythm - Blood pressure - ICP - CXR - Subjective responses - Mental function
355
What represents the greatest risk in patients receiving IPPB at high pressures?
Gastric distention
356
What is the most common complication associated with IPPB?
Inducing respiratory alkalosis
357
What are the **absolute** contraindications for IPPB?
-
358
What disease process causes an increase in **pulmonary compliance?**
Emphysema
359
Why is severe asthma so hard to manage with intubated patients?
Increased airway resistance **due to bronchospasm**
360
What mode of ventilation guarantees a set minute volume?
Volume control
361
What do you set in VC?
- VT - FiO2 - RR - PEEP - Flow
362
What do you set in PC?
- Inspiratory time - PEEP - FiO2 - RR - Inspiratory pressure
363
What does it mean if the patient does NOT return to baseline?
Airtrapping or auto-PEEP
363
Describe a pressure support breath.
1. Patient-triggered 2. Pressure-limited 3. Flow-cycled
364
Decreased compliance and elevated Pplat is indicative of _________.
Acute respiratory distress syndrome
365
What are some things that cause an increase of airway resistance?
- COPD - Excessive secretions - Water in tubing - Bronchospasm (E.g., asthma)
366
What disease process is **overly** compliant?
Emphysema
367
Alarms are especially important in what mode of ventilation?
Spontaneous mode
368
Describe APRV.
Provides 2 pressure. (High and low) Majority of the time is spent at the high level of pressure and there are short releases to blow off CO2. **Initially used to improve oxygenation.**