Increased Work of Breathing

Question 1

inc. WOB

Answer 1

¬ Can occur with respiratory distress, respiratory failure, COPD, anxiety, exertion
o Accessory muscle use
o RR
o Energy available for other organs

Question 2

Management of Increased WOB

Answer 2

1. Positioning

2. Breathing Control (BC)

Question 3

Positioning

Answer 3

1. Recovery positions
2. Supported positions
   o Forward lean sitting/standing
   o Relaxed sitting/standing
3. Recruitment of axiohumeral muscles
   o Reverse origin-insertion action
   o Assists respiration
   NB. Fixating the upper limb will allow the axiohumeral muscles to assist in breathing.

Question 4

Breathing Control (2)

Answer 4

• Gentle tidal breathing
• Emphasise lower chest, not upper chest
o Minimal effort expended
• Inspire through nose to warm, humidify and cleanse air (but through mouth if nose is blocked)
• Intersperse throughout other techniques for recovery to prevent airflow obstruction
• Duration of BC depends on patients presentation
• 2-3 breaths, up to minutes++

Question 5

Normal Airway Clearance

Answer 5

Depends on 2 main mechanisms:

1. Mucociliary clearance (MCC)
2. Effective cough (as a backup for impaired MCC)

Question 6

Impaired Airway Clearance

Answer 6

Breakdown of 1 or 2 mechanisms can lead to:
Secretions + Obstruction +/- Atelectasis
o Inhomogeneous ventilation > gas exchange > hypoxaemia
o inc. Infection risk > inc. Inflammatory response > chemical mediators (destroy lung tissue) > unstable airway

Question 7

Mucociliary Escalator

Answer 7

• Coordinated, unidirectional wave-like motion cilial motion to propel mucous
• Moves foreign particles toward trachea at 5 to 15 mm/min

Components
(1) Gel Layer:
o less water, more viscous
o Catches foreign material

(2) Sol layer:
o more water, less viscous
o * Cilia beat within this layer

Question 8

Factors Reducing Mucociliary Clearance ( dec. Cilial Beating)

Answer 8

¬ Temporary Causes (Medications, Dehydration, High inspired O2 concentration FiO2, Positive Pressure Ventilation, etc.)
¬ Permanent Causes (Smoking; Disease state: CF, Bronchiectasis)
¬ inc. Secretion volume/thickness

Question 9

Effect of Increased Secretions

Answer 9

Congested Airway
• dec. Cilial function
•inc. WOB  > Fatigue
• dec.Ventilation,  dec. V/Q ratio, dec. PaO2
• Long term damage/scarring

Question 10

2 Key Components for Management of Secretions:

Answer 10

1. Secretion MOBILISATION

2. Secretion REMOVAL