Breathlessness

Question 1

What is the typical diagnosis of dyspnoea?

Answer 1

↑ Load → Shortness of Breath ← ↑ Drive

Can be caused by:
- respiratory, cardiac, muscles weakness, metabolic, anaemia, psychogenic

Question 2

What is the ‘definition’

Answer 2

• It can be a normal physiological sensation but it can also be a symptom.
• Breathlessness is a group of sensations with multiple qualitative descriptors - described in terms of “how it is felt” :
  “Short of breath”
  “Can’t breathe”
  “Difficulty getting air in (or out)”
  “Not enough air” etc
• An all-embracing definition is difficult
• “Breathlessness arises when there is a recognition by the subject of an inappropriate relationship between respiratory work and total body work”

Question 3

What are the four key words required to define breathlessness?

Answer 3

Four Key Words: Recognition, Inappropriate, Respiratory Work, Total body Work

Question 4

Define: Recognition with respect to breathlessness.

Answer 4

• Perception of breathing has similarities to other sensory modalities such as pain, sound, light, so that a sensation arises at a conscious level
• Psychophysical experiments show a spectrum of perceptive ability in a normal population for sensation of breathing

Question 5

Define: Inappropriate with respect to breathlessness.

Answer 5

• Implies a bank of experience in which “appropriate” information is stored
• ie get used to a certain level of respiratory sensation for a certain level of total work (metabolic activity)

Question 6

Define: Respiratory Work with respect to breathlessness.

Answer 6

= ventilatory work

Normally mostly inspiratory; stretching work - elastic; airflow work - resistive (not restrictive)

Question 7

There are 5 Respiratory causes for dyspnoea?

Answer 7

1. Airways Disease
   a. Upper airways - tumour, foreign, angioneurotic oedema, croup
   b. Lower airways - asthma, COPD, bronchiolitis
2. Alveolar Disease
   - Pneumonia, lung collapse, pulmonary oedema, pulmonary fibrosis
3. Pulmonary Vascular Disease
   - Pulmonary embolism, vasculitis, primary pulmonary hypertension
4. Pleural and Chest Wall Disease
   - Pleural effusion, pneumothorax, chest wall deformity
5. Respiratory Muscle Disease
   - Respiratory muscle weakness, phrenic nerve palsy

Approximately 80% of dyspnoea is diagnosed with symptoms, signs and special tests. The rest are MUD (medically undiagnosed dyspnoea. Types of MUD Include:

- New clinical diseases
- Deconditioning
- Maximum effort sensations
- Psychogenic

Question 8

What are the symptoms and tests for Airways disease?

Answer 8

Airways Disease

a. Upper airways - tumour, foreign, angioneurotic oedema, croup
b. Lower airways - asthma, COPD, bronchiolitis

Causes: SOB, Cough, Sputum, Wheeze or stridor

Tests:
- lung function tests reveal obstructive ventilatory defect

May Present As:

• 68 year old with:
• -> Progressive exertional breathlessness, cough and sputum
• -> Exposure to tobacco smoke
• -> Signs of hyperinflation and scattered wheezes
• -> Lung function tests reveal obstructive ventilatory defect and reduced diffusion capacity
• -> –>COPD

Question 9

What are the symptoms and tests for Alveolar disease?

Answer 9

Alveolar Disease
- Pneumonia, lung collapse, pulmonary oedema, pulmonary fibrosis

Causes: SOB, Cough, Crepitations, +/- Orthopnoea

Tests:

• Lung Function Tests reveal Restrictive Ventilatory defect with reduced diffusion capacity
• CXR +/- High Resolution CT showing Alveolar & parenchymal defects

Question 10

What are the symptoms and tests for pulmonary vascular disease?

Answer 10

Pulmonary Vascular Disease
- Pulmonary embolism, vasculitis, primary pulmonary hypertension

Causes: SOB but normal chest examination +/- Haemoptysis, pleuritic pain, risk factors

Tests:
- diagnosed with a Wells Score

Question 11

Explain possible explanations for breathlessness in young athletes.

Answer 11

• normal sensation at maximal effort
• performance anxiety
• disease
• atopic asthma in 12-15% of Australian adults
• confirm with spirometry, MC challenge, skin tests
• Exercise induced bronchoconstriction in 30-40% elite athletes
• 40 % Hawthorn FC, Socceroos, Elite swimmers
• Diagnose with Eucapnoeic Voluntary Hyperventilation
• Responds to asthma treatment
• Vocal cord dysfunction
• Incidence in athletes but described more than in general population
• Confused with asthma
• Negative EVH, abnormal endoscopy
• Responds to speech therapy

Question 12

Explain the MUD: Deconditioning.

Answer 12

• variable pre-tests odds for disease on clinical history and examination
• negative or low probability tests
• Incremental exercise test to maximum
  
  • Low work load and VO2max
  • Steep heart rate response (small stroke volume)
  • Early anaerobic threshold
  • Excessive VEmax
  • No ECG, BP abnormalities or low SaO2
• Three month aerobic training program and then re-measure exercise capacity

Question 13

How would someone with psychogenic dyspnoea present?

Answer 13

Medical history
Presence of following should increase the suspicion of MUD
- A need to take a deep inspiration
- Oppressive chest or compressed chest
- Anxiety: nervous, restless
- Tingling in fingers, feet, face or head

Absence of following symptoms:

• Wheezing: whistling sounds while breathing
• Cough and expectoration
• Palpitation

Physical examination
- Normal examination of cardiopulmonary systems

Normal findings of following laboratory tests

• ECG, CXR, Spirometry
• Arterial blood gas analysis (respiratory alkalosis)