Transcript Airway Clearance Techniques in Cystic Fibrosis

AIRWAY CLEARANCE
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Karen Conyers, BSRT, RRT
Airway Clearance
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Pulmonary Physiology and Development
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Impaired Airway Clearance
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Airway Clearance Techniques
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Therapy Adjuncts
PULMONARY PHYSIOLOGY
AND DEVELOPMENT
Birth
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Respiratory Function
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Airways
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Terminal respiratory unit not fully developed
Respiratory function performed by alveolar-capillary bed
Little smooth muscle
Small airway diameter
Increased airway resistance
Lung compliance
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Incomplete elastic recoil
Decreased lung compliance
Age 2 Months
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Alveoli
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Respiratory muscles
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24 million alveoli present
Alveoli small but fully developed
Ability to form new alveoli
Underdeveloped accessory muscles
Diaphragm is primary muscle of respiration
Response to increased ventilatory demands
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Respiratory rate increases, not tidal volume
Ages 3 to 9 Months
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Increasing strength
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Baby learns to hold head up, reach for things
Upper body strength develops, including accessory
muscles for respiration
Changes in respiratory function
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Learns to sit up: rib cage lengthens
Greater chest excursion
Increased tidal volume
Age 4 Years
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Lung development
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Development of pre-acinar
bronchioles and collateral ventilation
(pores of Kohn)
Development of airway
smooth muscle
Age 8 Years
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Continued lung development
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Alveolar development complete
Alveolar size increases
Total lung volume increases
300 million alveoli (increased from 24 million
at age 2 months)
Adult Lung
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Gradual loss of volume
Loss of elasticity
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Environmental effects
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Decreasing compliance
Smoking
Air pollution
Occupational hazards
Disease effects
Factors Affecting Airflow
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Airway resistance
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Turbulent airflow
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Airway obstruction
Normal Airway Resistance
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Decreasing cross-sectional area from acinus to
trachea causes increased resistance, as airflow
moves from small to large airways.
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Cross-sectional areas:
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trachea diameter
4th generation bronchi
bronchioles
acinus cross-section
2 cm
20 cm
80 cm
400 cm
Greatest airway resistance in large airways; laminar
airflow in small airways
Airway Obstruction
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Increased airway resistance
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Bronchospasm
Inflammation
Hypersecretion of mucus
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Acute process
Chronic disorder
Mucus
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Mucus produced by goblet cells in airway
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Chronic airway irritation
of goblet cells
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increased numbers
larger quantities of mucus
Cilia move together in coordinated fashion to move
mucus up airways
IMPAIRED
AIRWAY CLEARANCE
Impaired Airway Clearance: Factors
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Ineffective mucociliary clearance
Excessive secretions
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Thick secretions
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Ineffective cough
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Restrictive lung disease
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Immobility / inadequate exercise
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Dysphagia / aspiration / gastroesophageal reflux
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Results of Impaired Airway Clearance
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Airway obstruction
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Mucus plugging
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Atelectasis
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Impaired gas exchange
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Infection
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Inflammation
A Vicious Cycle
Entering the Cycle
ASTHMA
NEUROMUSCULAR
WEAKNESS
PRIMARY
CILIARY
DYSKINESIA
ASPIRATION
GASTROESOPHAGEAL
REFLUX
CYSTIC
FIBROSIS
ASPERGILLOSIS
AIRWAY CLEARANCE
TECHNIQUES
Airway Clearance Techniques
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Goals
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Conventional Methods
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Newer Therapies
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Therapy Adjuncts
Goals
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Interrupt cycle of lung tissue destruction
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Decrease infection and illness
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Improve quality of life
Conventional methods
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Cough
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Chest Physiotherapy
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Exercise
Cough
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Natural response
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Only partially effective
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Frequent coughing leads to “floppy” airways
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May be suppressed by patient
Chest Physiotherapy (CPT)
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Can be used with infants
Requires caregiver participation
Technique dependent
Time consuming
Physically demanding
Requires patient tolerance
Effectiveness debated
Exercise
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Recommended for most patients
Pulmonary rehabilitation expectation
Training
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Ability to exercise related more to muscle mass
than to pulmonary function
Improves oxygen uptake by muscle cells
Many patients limited by physical disability
Newer Therapies
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PEP valve
Flutter
In-Exsufflator
HFCWO (Vest)
Intrapulmonary percussive ventilation (IPV)
Cornet
PercussiveTech HF
PEP valve
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Positive Expiratory Pressure
Action: splints airways during exhalation
Can be used with aerosolized medications
Technique dependent
Portable
Time required: 10 - 15 minutes
Flutter
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Action: loosens mucus through expiratory
oscillation; positive expiratory pressure splints
airways
Used independently
Technique dependent
Portable
May not be effective at low airflows
Time required: 10 - 15 minutes
In-Exsufflator
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Action: creates mechanical “cough” through the
use of high flows at positive and negative pressures
Positive/negative pressures up to 60 cm of water
Used independently or with caregiver assistance
Technique independent
Portable
ABI Vest (HFCWO)
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Action: applies High Frequency Chest Wall
Oscillation to entire thorax; moves mucus from
peripheral to central airways
Used independently or with minimal caregiver
supervision
May be used with aerosolized medications
Technique independent
Portable
Time required: 15-30 minutes
Intrapulmonary Percussive Ventilation (IPV)
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Action: “percussion” on inspiration, passive
expiration; dense, small particle aerosol
Used independently or with caregiver
supervision
Used with aerosolized meds
Technique dependent
May not be well tolerated by patient
Time required: 20 minutes
Other devices
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Cornet
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Similar to action of Flutter
Lower cost, disposable
PercussiveTech HF
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Hand-held device used with aerosol meds
Similar to action of IPV
Requires 50 PSI gas source
European / Canadian Techniques
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Huff cough (forced expiratory technique)
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Active Cycle of Breathing Technique (ACBT)
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Autogenic Drainage
Forced Expiratory Technique
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“Huff” cough
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Three second breath hold
Open glottis
Prevents airway collapse
Effective technique for “floppy” airways
Easy to learn
Active Cycle of Breathing Technique
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Three steps:
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Breathing control
Thoracic expansion / breath hold
Forced expiratory technique
May be performed independently
Easily tolerated
Autogenic Drainage
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Three phases
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Unsticking
Collecting
Evacuating
May be performed independently
Harder to teach and to learn than other techniques
May be difficult for very sick patients to perform
Autogenic Drainage
Cough
IRV
UNSTICKING
VT
Normal
Breathing
ERV
RV
Complete
Exhalation
COLLECTING
EVACUATING
THERAPY
ADJUNCTS
Therapy Adjuncts
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Antibiotics
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Bronchodilators
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Anti-inflammatory drugs
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Mucolytics
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Nutrition
Antibiotics
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Oral
Intravenous
Nebulized
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Aminoglycosides: P. aeruginosa
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Gentamycin: 40-80 mg
Tobramycin: 40-120 mg
Tobi: 300 mg per dose: high dose inhibits mutation of
P. aeruginosa in lung
Bronchodilators
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Hyperreactive airways common in many
pulmonary conditions
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Albuterol, Atrovent
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MDI or nebulized
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Administered prior to other therapies
Mucolytics
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Mucomyst (acetylcysteine)
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Pulmozyme (dornase alfa or DNase)
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Breaks disulfide bonds
Airway irritant
Targets extracellular DNA in sputum
Specifically developed for cystic fibrosis
Hypertonic saline
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Sputum induction
Australian studies
Anti-inflammatory Drugs
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Inhaled steroids via metered dose inhaler
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Oral or IV prednisone
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High-dose ibuprofen (cystic fibrosis)
Nutrition
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Connection between nutrition and lung function!
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Worsening lung function
increased work of
breathing & frequent coughing
increased
caloric need
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Increasing dyspnea
decreased caloric intake
malnutrition
decreased ability to fight
infection
worsening lung function
Interrupting the Vicious Cycle
AIRWAY
CLEARANCE
TECHNIQUES