1. AIRWAY CLEARANCE
Karen Conyers, BSRT, RRT

2. Airway Clearance Pulmonary Physiology and Development
Impaired Airway Clearance
Airway Clearance Techniques
Therapy Adjuncts

3. PULMONARY PHYSIOLOGY
AND DEVELOPMENT

4. Birth Respiratory Function Airways Lung compliance
Terminal respiratory unit not fully developed
Respiratory function performed by alveolar-capillary bed
Airways
Little smooth muscle
Small airway diameter
Increased airway resistance
Lung compliance
Incomplete elastic recoil
Decreased lung compliance

5. Age 2 Months Alveoli Respiratory muscles
24 million alveoli present
Alveoli small but fully developed
Ability to form new alveoli
Respiratory muscles
Underdeveloped accessory muscles
Diaphragm is primary muscle of respiration
Response to increased ventilatory demands
Respiratory rate increases, not tidal volume

6. Ages 3 to 9 Months Increasing strength Changes in respiratory function
Baby learns to hold head up, reach for things
Upper body strength develops, including accessory muscles for respiration
Changes in respiratory function
Learns to sit up: rib cage lengthens
Greater chest excursion
Increased tidal volume

7. Age 4 Years Lung development
Development of pre-acinar bronchioles and collateral ventilation (pores of Kohn)
Development of airway smooth muscle

8. Age 8 Years Continued lung development Alveolar development complete
Alveolar size increases
Total lung volume increases
300 million alveoli (increased from 24 million at age 2 months)

9. Adult Lung Gradual loss of volume Loss of elasticity
Decreasing compliance
Environmental effects
Smoking
Air pollution
Occupational hazards
Disease effects

10. Factors Affecting Airflow
Airway resistance
Turbulent airflow
Airway obstruction

11. Normal Airway Resistance
Decreasing cross-sectional area from acinus to trachea causes increased resistance, as airflow moves from small to large airways.
Cross-sectional areas:
trachea diameter cm
4th generation bronchi cm
bronchioles cm
acinus cross-section cm
Greatest airway resistance in large airways; laminar airflow in small airways

12. Airway Obstruction Increased airway resistance Hypersecretion of mucus
Bronchospasm
Inflammation
Hypersecretion of mucus
Acute process
Chronic disorder

13. Mucus Mucus produced by goblet cells in airway
Chronic airway irritation increased numbers of goblet cells larger quantities of mucus
Cilia move together in coordinated fashion to move mucus up airways

14. IMPAIRED
AIRWAY CLEARANCE

15. Impaired Airway Clearance: Factors
Ineffective mucociliary clearance
Excessive secretions
Thick secretions
Ineffective cough
Restrictive lung disease
Immobility / inadequate exercise
Dysphagia / aspiration / gastroesophageal reflux

16. Results of Impaired Airway Clearance
Airway obstruction
Mucus plugging
Atelectasis
Impaired gas exchange
Infection
Inflammation

17. Impaired airway clearance
A Vicious Cycle
Impaired airway clearance
Mucus
retention
Mucus plugging,
obstruction
Lung
damage
Lung
infection
Inflammation,
mucus production

18. Impaired airway clearance
Entering the Cycle
ASTHMA
NEURO-
MUSCULAR
WEAKNESS
Impaired airway clearance
PRIMARY
CILIARY
DYSKINESIA
Mucus
Retention
Mucus plugging,
Obstruction
ASPIRATION
Lung
Infection
Lung
Damage
CYSTIC
FIBROSIS
GASTRO-
ESOPHAGEAL
REFLUX
Inflammation,
Mucus production
ASPERGILLOSIS

19. AIRWAY CLEARANCE
TECHNIQUES

20. Airway Clearance Techniques
Goals
Conventional Methods
Newer Therapies
Therapy Adjuncts

21. Goals Interrupt cycle of lung tissue destruction
Decrease infection and illness
Improve quality of life

22. Conventional methods
Cough
Chest Physiotherapy
Exercise

23. Cough Natural response Only partially effective
Frequent coughing leads to “floppy” airways
May be suppressed by patient

24. Chest Physiotherapy (CPT)
Can be used with infants
Requires caregiver participation
Technique dependent
Time consuming
Physically demanding
Requires patient tolerance
Effectiveness debated

25. Exercise Recommended for most patients
Pulmonary rehabilitation expectation
Training
Ability to exercise related more to muscle mass than to pulmonary function
Improves oxygen uptake by muscle cells
Many patients limited by physical disability

26. Newer Therapies PEP valve Flutter In-Exsufflator HFCWO (Vest)
Intrapulmonary percussive ventilation (IPV)
Cornet
PercussiveTech HF

27. PEP valve Positive Expiratory Pressure
Action: splints airways during exhalation
Can be used with aerosolized medications
Technique dependent
Portable
Time required: minutes

28. Flutter
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: minutes

29. In-Exsufflator
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

30. ABI Vest (HFCWO)
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: minutes

31. Intrapulmonary Percussive Ventilation (IPV)
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

32. Other devices Cornet PercussiveTech HF Similar to action of Flutter
Lower cost, disposable
PercussiveTech HF
Hand-held device used with aerosol meds
Similar to action of IPV
Requires 50 PSI gas source

33. European / Canadian Techniques
Huff cough (forced expiratory technique)
Active Cycle of Breathing Technique (ACBT)
Autogenic Drainage

34. Forced Expiratory Technique
“Huff” cough
Three second breath hold
Open glottis
Prevents airway collapse
Effective technique for “floppy” airways
Easy to learn

35. Active Cycle of Breathing Technique
Three steps:
Breathing control
Thoracic expansion / breath hold
Forced expiratory technique
May be performed independently
Easily tolerated

36. Autogenic Drainage Three phases May be performed independently
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

37. Autogenic Drainage Cough IRV VT ERV RV COLLECTING EVACUATING
UNSTICKING VT
Normal
Breathing
ERV RV
Complete
Exhalation

38. THERAPY
ADJUNCTS

39. Therapy Adjuncts Antibiotics Bronchodilators Anti-inflammatory drugs
Mucolytics
Nutrition

40. Antibiotics Oral Intravenous Nebulized Aminoglycosides: P. aeruginosa
Gentamycin: mg
Tobramycin: mg
Tobi: 300 mg per dose: high dose inhibits mutation of P. aeruginosa in lung

41. Bronchodilators
Hyperreactive airways common in many pulmonary conditions
Albuterol, Atrovent
MDI or nebulized
Administered prior to other therapies

42. Mucolytics Mucomyst (acetylcysteine) Pulmozyme (dornase alfa or DNase)
Breaks disulfide bonds
Airway irritant
Pulmozyme (dornase alfa or DNase)
Targets extracellular DNA in sputum
Specifically developed for cystic fibrosis
Hypertonic saline
Sputum induction
Australian studies

43. Anti-inflammatory Drugs
Inhaled steroids via metered dose inhaler
Oral or IV prednisone
High-dose ibuprofen (cystic fibrosis)

44. Nutrition Connection between nutrition and lung function!
Worsening lung function increased work of breathing & frequent coughing increased caloric need
Increasing dyspnea decreased caloric intake
malnutrition decreased ability to fight infection worsening lung function

45. Interrupting the Vicious Cycle
Impaired airway clearance
NUTRITION
MUCOLYTICS
Mucus plugging,
obstruction
Mucus
retention
AIRWAY
CLEARANCE
TECHNIQUES
BRONCHODILATORS
Lung Damage
Lung infection
INFLAMMATORIES
ANTI -
ANTIBIOTICS
Inflammation,
mucus production