Chapter 9 Ventilation Assistance Flashcards
1
Q
Essential nursing interventions (3)
A
- Maintain adequate airway
- Ensure adequate ventilation
- Ensure adequate oxygenation
2
Q
Respiratory A & P
- Function is?
- Lungs
- Upper airway
- Lower airway
A
- Function is gas exchange
- Lungs
- Left: two lobes
- Right: three lobes
- Upper airway
- Nasal cavity
- Pharynx
- Lower airway
- Larynx
- Trachea
- Right and left mainstem bronchi, bronchioles, and alveoli
3
Q
Physiology of Breathing
- Rest
- Inspiration
- Expiration
A
- Rest:
- Intrapleural pressure < atmospheric
- Intraalveolar = atmospheric
- Inspiration:
- Intrapleural pressure more negative
- Intraalveolar negative = airflow
- Expiration:
- Passive when intrapulmonary
pressure exceeds atmospheric
- Passive when intrapulmonary
4
Q
Gas Exchange
- Ventilation =
- Diffusion of O2 and CO2 at?
- Oxygenated blood is?
- Diffusion of O2 and CO2 occurs at?
A
- Ventilation = movement of O2 and CO2 in and out of alveoli
- Diffusion of O2 and CO2 at pulmonary capillary
- Oxygenated blood perfused or transported to the tissues
- Diffusion of O2 and CO2 occurs at cellular level
* Transport of CO2 to the right side of the heart
* Diffusion based on concentration gradients
5
Q
Regulation of Breathing
- Respiration is stimulated by?
- COPD patients?
A
- Respiration stimulated by elevated CO2
- Not true for COPD
- Stimulus is hypoxia
- Rationale for low oxygen in patients with COPD
6
Q
- Work of Breathing (WOB)
A
- Amount of effort required to maintain ventilation
- Respiratory pattern changes automatically
- WOB increases, more energy needed
- WOB high, leads to muscle fatigue and eventually respiratory failure
7
Q
Compliance
- What is it?
- Types
A
- Distensibility or stretch
- Determined by elasticity, “recoil”
- Elastic recoil and compliance are inversely related
- Types
- Static—measured under condition of no airflow (inspiratory hold)
- Dynamic—measured while gases flowing
8
Q
Resistance
A
- Opposition to gas flow in the airways
- Airway length
- Airway diameter
- Small tube
- Spasms
- Mucus
- Flow rate of gases
- Increased breathing effort
9
Q
Lung Volumes and Capacities (2)
A
- Assess baseline function
- Monitor responses
10
Q
Selected Measures
- Tidal Volume (TV)
- Functional Residual Capacity (FRC)
- Vital Capacity (VC)
A
- Tidal Volume (TV)
- Normal breath; 500 mL or 5 to 7 mL/kg
- Functional Residual Capacity (FRC)
- Volume of gas remaining in the lungs at normal resting expiration
- Average: 2300 mL
- Vital Capacity (VC)
- Maximum volume of gas forcefully expired after maximum inspiration
- Average: 4600 mL
11
Q
Health History (8)
A
- Tobacco pack per year history
- Occupational history
- Sputum production
- Shortness of breath, dyspnea, cough, anorexia, weight loss, and chest pain
- Oral and inhalant respiratory medicines
- OTC drugs
- Allergies: medication and environmental
- Last chest x-ray and tuberculosis screen
12
Q
Physical Examination
- Inspection
- Respiratory rate
A
- Inspection
- Head, neck, fingers, and chest
- Accessory muscles, sternal retractions, nasal flaring, asymmetrical chest movements, open-mouth breathing, and gasping breaths
- Respiratory rate
- Tachypnea: rate > 20
- Bradypnea: rate < 10
- Assess rate and depth and altered patterns
13
Q
Abnormal Breathing Patterns (4)
A
- Cheyne-Stokes: cyclical with apneic periods
- Biot’s: cluster breathing
- Kussmaul’s: deep, regular, and rapid
- Apneustic: gasping inspirations
14
Q
Cheyne-Stokes
A
Respirations gradually increase in depth, then become more shallow; followed by a period of apnea
15
Q
Biot’s
A
Highly irregular breathing pattern with abrupt pauses between efforts
16
Q
Kussmaul’s
A
Respiration faster and deeper without pauses
17
Q
Apneustic
A
Respirations prolonged, gasping, followed by extremely short, inefficient expiration
18
Q
Palpation
-Evaluate (5)
A
- Chest wall excursion
- Tracheal deviation
- Chest wall tenderness
- Subcutaneous crepitus
- Tactile fremitus
19
Q
Percussion
- Resonance:
- Dullness:
- Flatness:
- Hyperresonance:
- Tympany:
A
- Resonance: normal lung sound
- Dullness: denser than normal tissue
- Flatness: air is absent
- Hyperresonance: increased amount of air
- Tympany: air-filled area
20
Q
Auscultation
- Assess?
- Environment
- Approach
A
- Assess breath sounds, presence of adventitious lung sounds, voice sounds
- Quiet environment
- Systematic approach
21
Q
Breath Sounds
- Normal
- Advenitious
A
- Normal
- Bronchial
- Bronchovesicular
- Vesicular
- Adventitious sounds
- Crackles
- Rhonchi
- Wheezes
- Pleural friction rub
- Stridor
22
Q
Arterial Blood Gases
A
- Adequacy of oxygenation and ventilation
- Acid-base status
- Interpret in conjunction with:
- Clinical history
- Physical assessment
23
Q
Oxygenation
- PaO2─partial pressure of oxygen dissolved in arterial blood
- SaO2─amount of oxygen bound to hemoglobin
A
- PaO2─partial pressure of oxygen dissolved in arterial blood
- Normal value 80 to 100 mm Hg
- Decreases in elderly
- Value < 60 mm Hg treated
- Value < 40 mm Hg is life threatening
- SaO2─amount of oxygen bound to hemoglobin
- Normal value 92% to 99%
- Frequently measured via pulse oximetry (SpO2)
24
Q
Hypoxemia:
A
decreased oxygenation of arterial blood
25
Hypoxia:
decreased oxygenation at tissue level
26
PaO2 and SaO2 Relationship
- Oxyhemoglobin dissociation curve
- Critical zone: PaO2 < 60 mm/Hg
- Shifts of oxyhemoglobin dissociation curve
* Acidosis: release of oxygen to tissues
* Alkalosis: hemoglobin holds on to oxygen
27
pH
- Concentration
- Normal range
- Concentration of hydrogen ions (H+)
- Normal range 7.35 to 7.45
* pH < 7.35 = acidosis
* pH > 7.45 = alkalosis
28
PaCO2
- What is it?
- Normal value
- Partial pressure of carbon dioxide in arterial blood
- Normal value 35 to 45 mm Hg
* PaCO2 > 45 mm Hg = Acidosis
* PaCO2 < 35 mm Hg = Alkalosis
29
HCO3— Bicarbonate
- What is it?
- Normal value
- Concentration of sodium bicarbonate in the blood
- Normal value is 22 to 26 mEq/L
* HCO3 < 22 = Acidosis
* HCO3 > 26 = Alkalosis
30
Buffer System
- Maintain body’s pH
| - Substances that change the pH when either acids or bases are added
31
Bicarbonate Buffer System
- Most common
- Activated as H+ ions increase
- Increased H+ ions combined with HCO3 to form carbonic acid (H2CO3)
- Carbonic acid breaks down into H2O and CO2
32
Respiratory Buffer System
- Excretes excess CO2 from system when metabolic disorder occurs
- Immediate action
33
Base Excess or Base Deficit
- Normal range
- Base deficit occurs when?
- Base excess occurs when?
- The normal range for base deficit/base excess is −2 to +2 mEq/L.
- Base deficit occurs when all body’s buffers are used up – Acidosis
- Base excess occurs when the body’s buffers are increased - Alkalosis
34
Compensation
1)
2)
3)
1) None
2) Partial: mechanisms occurring; pH abnormal
3) Complete: mechanisms occurring; pH normal range
35
Interpretation of ABGs
STEP 1: Look at each number and label
STEP 2: Evaluate oxygenation
STEP 3: Determine acid-base status. Evaluate the pH
STEP 4: Determine the primary cause of the acid-base status (respiratory or metabolic)
STEP 5: Determine compensation (absent, partial, or complete)
36
Oxygenation
- Pulse oximetry (SpO2) noninvasive measure
* Value of 90% = PaO2 60 mm Hg
- Ensure accurate readings
* Limit movement
* Avoid edematous areas
* Effect of sunlight, fluorescent light, nail polish, artificial nails, and dyes
- Periodic ABGs to compare value with SaO2
37
Assessment of Ventilation
- End-tidal Co2 (ETCO2)
- CalorimetricCo2 detector
- End-tidalCO2 (ETCO2)
* Must compare with ABGs and use for trending
* Values tend to be 2 to 5 mm Hg less than PaCO2
- CalorimetricCO2 detector
* Disposable devices
38
Oxygen Administration
- Oxygen to treat or prevent hypoxemia
- Humidification
* Flow rates > 4 L/min
* Mechanical ventilation
- Delivery devices
* Low flow: nasal cannula
* High flow: nasal cannula
* Simple face mask
* Reservoir systems
* Venturi or air-entrainment mask
39
Oxygen Delivery Devices
- Fraction of delivered oxygen (FiO2)
- Nasal cannula =
- High-flow cannula =
- Simple face mask =
- Face masks w/ reservoirs
* Partial rebreather =
* Nonrebreather =
- Air-entrainment mask =
- Manual resuscitation bags
- Fraction of delivered oxygen (FiO2)
* Room air 21% or 0.21 FiO2
- Nasal cannula = 0.24-0.44 FiO2
- High-flow cannula = 0.60-0.90 FiO2
- Simple face mask = 0.30-0.60 FiO2
- Face masks w/ reservoirs
* Partial rebreather = 0.35-0.60 FiO2
* Nonrebreather = 0.60-0.80 FiO2
- Air-entrainment mask = varied, depending on size of jet orifice
- Manual resuscitation bags
* 15 L/min to deliver 1.00 FiO2
40
Airway Management
- Positioning
- Devices
* Oral airway
* Nasopharyngeal airway
* Endotracheal intubation
41
Endotracheal Intubation
| -What is it and why is it used?
- Insertion of an endotracheal tube (ETT) through the mouth or nose
* Orotracheal route preferred to reduce infections
- Used to:
* Maintain an airway
* Remove secretions
* Prevent aspiration
* Provide mechanical ventilation
42
```
Which is an advantage of nasotracheal intubation?
A.Easier to remove secretions from tube
B. Less likely to kink
C. More comfortable for the patient
D. Reduces risk of sinusitis
```
More comfortable for the patient
43
Endotracheal Intubation (13)
- Right size tube
* 7.5 to 8.0 mm female; 8.0 to 9.0 mm male
- Check balloon on tube for leak
- Stylet
- Lubricate tube
- Laryngoscope and blade
- Sniffing position
- Premedicate prn
- Topical anesthetic/ paralytic medication
- Ventilate patient
- Suction oropharynx
- Intubate within 30 sec (hyperoxygenate them)
- Inflate balloon
- Verify placement
44
Verify Placement (7 Steps)
- Auscultate epigastric area
- Auscultate bilateral breath sounds
- ETCO2 detector
- Esophageal detector device
- Chest x-ray—3 to 4 cm above carina
- Secure tube when placement is verified
- Record cm at the lip line for reference
45
- How do you tell if the ET tube is in the right mainstem bronchus?
- What do you do if you suspect the ET tube is in the esophagus?
- Unequal breath sounds and inflation, more on right sound
| - gurgling, saturations are declining, no CO2
46
Nasotracheal Intubation (3)
- Pass through the patient’s naris
- Blind visualization
- Direct visualization
47
Tracheostomy
- Indications
- Where is it performed?
- Indications
* Long-term mechanical ventilation
* Frequent suctioning
* Protecting the airway
* Bypass an airway obstruction
* Reduce WOB
- Performed in the operating room or bedside (percutaneous)
48
When is a tracheostomy done early in the course of airway management?
Trauma, upper airway trauma, critically ill, chronic lung disease
49
Tracheostomy (4)
- Cuffed versus cuffless tracheostomy tube
- Single versus double cannula
- Fenestrated tracheostomy tube
- Speaking tracheostomy valves
50
Endotracheal Suctioning
- Suction as indicated by assessment
- Procedures
- Suction as indicated by assessment
* Visible secretions
* Coughing
* Rhonchi
* High PIP on ventilator
* Ventilator alarm
- Conventional versus closed suction
- Procedures
* Hyperoxygenate throughout procedure
* Avoid normal saline instillation
51
Indications for Ventilation (3)
- Hypoxemia
* PaO2 ≤ 60 mm Hg on FiO2 > 0.5
- Hypercapnea
* PCO2 ≥ 50 mm Hg with pH ≤ 7.25
- Progressive deterioration
* Increasing RR
* Decreasing VT
* Increase in WOB
52
Ventilator Settings (4 Settings)
- FiO2
- Tidal Volume (VT)
* 6 to 8 mL/kg (ideal weight)
* Adjusted according to peak and plateau pressures
- Respiratory rate
* 14-20 breaths initially
- I:E ratio; normal 1:2
53
Ventilator Settings
- Positive end-expiratory pressure (PEEP)
- Sensitivity; amount of patient effort
- Positive end-expiratory pressure (PEEP)
* 5-20 cm H2O
* Increases FRC to improve oxygenation
* Can cause reduced cardiac output if high and impedes venous return
- Sensitivity; amount of patient effort
* Goal is to avoid patient-ventilator dyssynchrony (“fighting the ventilator”)
54
Auto-PEEP
- What is it?
- What is it caused by?
- Assess by?
- Auto Peep=
- Spontaneous development of PEEP
- Caused by gas trapping
* Insufficient expiratory time
* Incomplete exhalation
- Rapid RR
- Airflow obstruction
- Inverse I:E ventilation
- Assess by 2-sec pause (hold) maneuver
- Auto-PEEP = Total PEEP – Set PEEP
55
Data to Monitor During Mechanical Ventilation
1)
2)
3)
- Exhaled tidal volume (EVT)
* Should not be more than 50 mL
different from set VT
- Peak inspiratory pressure (PIP)
* Should be less than 40 mm Hg
- Total respiratory rate
* Count total rate, which accounts for set rate and patient effort
56
Volume Ventilation
- What is it?
- 2 Types
- The VT delivered by the ventilator is constant
- Types
* Volume assist/control (V-A/C)
* Synchronized intermittent mandatory ventilation (SIMV)
57
Volume Assist/Control Ventilation (V-A/C) (6)
- Preset number of breaths at preset VT
- Patient may trigger additional breaths
- VT does not vary
- Ventilator performs most of the WOB
- Useful in normal respiratory drive but weak or unable to exert WOB
- Risk of hyperventilation and respiratory alkalosis
58
Pressure Ventilation
- Ventilator set to allow airflow until preset pressure is reached
- VT is variable
- PIP can be better controlled
- Risk of hypoventilation and respiratory acidosis
- Includes CPAP, pressure support (PSV), pressure A/C, inverse-ratio ventilation, and airway pressure release (APRV)
59
CPAP
- Continuous positive airway pressure throughout respiratory cycle to patient who is spontaneously breathing
* Similar to PEEP
* Via ventilator or nasal or face mask
* Option for patients with sleep apnea
- May facilitate weaning
- Can also be used to prevent reintubation
60
Pressure Support (PS)
- Patient’s spontaneous effort is assisted by preset amount of positive pressure
* 6 to 12 cm H2O
- Decreases WOB with spontaneous
breaths
- Also useful in weaning
61
Pressure Assist Control (P-A/C)
- Set respiratory rate
- Every breath augmented by set amount of inspiratory pressure
- If patient triggers breath, these breaths are enhanced with positive pressure
62
Advanced Modes
- Pressure-Controlled Inverse-Ratio Ventilation
| - Airway pressure-release ventilation (APRV)
63
High- Frequency Oscillatory Ventilation (HFOV)
- Delivers low tidal volume at very fast rate (300-420 bpm)
- Used in patients with noncompliant lungs (such as ARDS) who remain hypoxemic despite conventional and advanced ventilation
- Close monitoring essential
- Sedation and paralysis may be indicated
64
Noninvasive Positive- Pressure Ventilation (NPPV)
- Delivery of positive-pressure ventilation (PPV) without artificial airway
* Via face mask, nasal pillow
* Tight seal
* Intact respiratory drive
- Reduces complications associated with MV
- Useful in many patients
* COPD
* Heart failure
* Palliative care
- Examples
* Nasal CPAP
* BiPAP
- Used in conjunction with portable ventilator
- Requirements
* Tight seal of mask
* Intact respiratory drive
* Able to protect airway
65
Which patient would probably not be a candidate for NPPV?
A. COPD with acute pneumonia
B. Heart failure exacerbation in need of
diuretics
C. Drug overdose with shallow respirations
D. Asthma exacerbation in need of bronchodilators and steroids
C. Drug overdose with shallow respirations
66
Alarms and Interventions
- Never shut alarms off; silence only
| - Manually ventilate if uncertain of problem
67
Types of Alarms
- High peak pressure
- Low pressure; low PEEP/CPAP
- Low exhaled tidal volume
- Low minute ventilation
- High exhaled tidal volume
- High minute ventilation
- Apnea
68
```
The nurse assesses a patient with an ETT and mechanical ventilation whose high peak pressure alarm is sounding. A cause of this alarm is:
A. Anxiety
B. Biting or kinking of ETT
C. Disconnected ventilator circuit
D. Patient not initiating any breaths
```
B. Biting or kinking of ETT
| -high peak means there is some sort of block.
69
Unplanned Extubation
- Nurse must protect airway to prevent unplanned extubation
- Securing the tube is important
- Support patient’s ventilation-BVM
70
Laryngeal/ Tracheal Injury
- Prevent excessive head movement
- Routine monitoring of ETT cuff pressure
* Keep no higher than 25 to 30 cm H2O
71
Damage to Oral and Nasal Mucosa
Skin breakdown from tape and commercial devices
72
Barotrauma
- Examples
- Detect
- Examples
* Pneumothorax
* Tension pneumothorax
- Detect
* High PAP, mean airway pressure
* Decreased breath sounds
* Tracheal shift
* Subcutaneous crepitus
* Hypoxemia
73
Barotrauma
| -Treat tension pneumothorax emergently
- Manually ventilate
| - Needle thoracostomy
74
Volutrauma
- Overdistension of alveoli
- Damages the lung similar to early ARDS
- Keep PIP < 40 cm H2O
75
Oxygen Toxicity
- The degree of injury is related to the duration of exposure and to the FiO2, not to the PaO2.
- Signs
* Tracheobronchitis
* the FiO2 of 1.0 may be tolerated for 24 hours
* Atelectasis
76
Infection
- Normal protective mechanisms bypassed by ETT tube
* Ventilator-associated pneumonia (VAP)
- Ventilator bundle
* Head of bed 30 degrees
* Awaken daily and assess readiness to wean
* Stress ulcer prophylaxis
* DVT prophylaxis
* Oral care (chlorhexidine in some bundles)
77
Research-Based Ventilator Associated Pneumonia (VAP) Prevention
- Elevate head of bed 30 to 45 degrees
- Prevent drainage of condensate back to patient
- Hand hygiene
- ETT with subglottic suction capability
- Aspirate secretions from above ETT
- Oral hygiene program
- Noninvasive ventilation as possible
78
Ventilator- Associated Events
- New concept of identifying ventilator- associated events rather than just VAP
- Determined by worsening oxygenation or higher PEEP needs after patient has shown improvement
- May indicate infection or other respiratory complication
79
Dysphagia and Aspiration
* Dysphagia is common after extubation
| * Assess swallowing prior to initiating oral feedings
80
Cardiovascular System
- Hypotension
| - Decreased cardiac output, especially with PEEP
81
GI System
- Complications
- Interventions
- Complications
* Stress ulcers
* GI bleeding
- Interventions
* Stress ulcer prophylaxis
* Provide nutritional support
82
Psychosocial Complications
- Stress
- Anxiety
- Dyssynchrony
- Noise
- Altered sleep-wake patterns
- Dependence
83
Communication with ET Tube
- Lack of vocal expression
- Ineffective communication
- Major stressors
* Fear
* Frustration
* Isolation
* Anger
* Helplessness
* Anxiety
* Sleeplessness
84
Medications
- Analgesics: morphine
- Sedatives: benzodiazepines, neuroleptics, and propofol
- Neuromuscular blocking agents (NMBAs): paralytic agents
85
PPN and TPN
TPN has to be in superior vena cava
86
Non- pharmacological Interventions
- Create a healing environment
* Focus the plan of care on patient and family
* Reduce noise levels
* Reduce light stimulation
* Provide reassurance
* Adequate rest with near-normal sleep- wake cycles
* Orientation measures (time, place)
- Complementary and alternative measures
* Therapeutic touch
* Guided imagery/relaxation
* Spirituality/prayer
87
Weaning Patients from Ventilator: Liberating
- Individualized decisions
| - Collaborative team effort
88
Readiness to Wean
- Underlying cause for mechanical ventilation resolved
- Hemodynamic stability; adequate cardiac output
- Adequate respiratory muscle strength
- Adequate oxygenation without a high FiO2 and/or high PEEP
- Absence of factors that impair weaning
- Mental readiness
- Minimal need for medicines that cause respiratory depression
89
Weaning Trial
Weaning trial or spontaneous breathing trial (SBT)
90
Weaning Methods
- Review Table 9-5
- Synchronized intermittent mechanical ventilation
- Pressure support
- T-piece trials
- CPAP
91
Stop the Weaning Process
| -Respiratory
- Respiratory rate > 35 or < 8 breaths/min
- Low spontaneous VT < 5 mL/kg
- Labored respirations
- Use of accessory muscles
- Abnormal breathing pattern
- Low oxygen saturation < 90%
92
Stop the Weaning Process
| -Cardiovascular
- HR or BP changes > 20% from baseline
- Dysrhythmias (e.g., PVCs)
- ST-segment elevation
- Blood pressure changes more than 20% from baseline
- Diaphoresis
93
Stop the Weaning Process
| -Neurologic
- Decreased level of consciousness
- Anxiety/agitation
- Subjective discomfort
94
Extubation
- Determine need for secretion management
- Assess
* Stridor
* Hoarseness
* Change in vital signs
* Low oxygen saturation
- NPPV may prevent need for reintubation
