Shortness of Breath

Question 1

List some broad mechanisms that can lead to shortness of breath. Give an example of a disease that falls under each of these mechanisms.

Answer 1

Insufficient oxygen entering the lungs – COPD Insufficient oxygen entering the blood - emphysema Insufficient oxygen reaching the tissues - anaemia Increased respiratory drive - acidaemia

Question 2

Which diseases can cause an inability to fully inflate the lungs?

Answer 2

Increased work – due to obesity and stiffness due to interstitial lung disease Weak respiratory muscles – Guillain-Barre syndrome, myasthenia gravis Hyperinflated lungs – COPD

Question 3

Which diseases can cause insufficient oxygen to be delivered across the body?

Answer 3

Anaemia Reduced cardiac output (e.g. heart failure, aortic stenosis) Shock (e.g. sepsis, hypovolaemia)

Question 4

What are two important features of the history of presenting complaint of a patient presenting with shortness of breath?

Answer 4

Time of onset Alleviating/exacerbating factors

Question 5

When does asthma tend to get worse?

Answer 5

At night On exercise On exposure to triggers (e.g. the cold)

Question 6

List some important risk factors that are associated with various causes of shortness of breath.

Answer 6

Smoking Pets Occupational history Medications Past medical history

Question 7

Which occupational disease is associated with chronic dust inhalation?

Answer 7

Pneumoconiosis

Question 8

List some drugs that are associated with interstitial lung disease.

Answer 8

Methotrexate Amiodarone Nitrofurantoin

Question 9

List some autoimmune diseases that are associated with interstitial lung disease.

Answer 9

Rheumatoid arthritis Sarcoidosis SLE

Question 10

List some important associated symptoms that you should enquire about in a patient presenting with shortness of breath.

Answer 10

• Cough (and haemoptysis)
• Chest pain
• Muscular weakness or fatigue
• Tender limbs
• Weight loss, loss of appetite, night sweats
• Fever
• Loss of blood

Question 11

Describe the pattern of cough in: Pneumonia Chronic bronchitis Asthma

Answer 11

• Pneumonia 3-4 day history of persistent, productive cough - Chronic bronchitis Persistent, productive cough on most days of the past 3 months and spanning years - Asthma Dry cough present mainly during episodes of shortness of breath or at night

Question 12

List some causes of blood-stained sputum.

Answer 12

Cavitating pneumonia PE Lung cancer Bronchiectasis

Question 13

List some diseases that cause pleuritic chest pain and shortness of breath.

Answer 13

Pneumonia PE Pneumothorax

Question 14

Which differentials would you consider if a patient complains of shortness of breath and muscle weakness/fatigue?

Answer 14

Myasthenia gravis Lambert-Eaton syndrome Motor neurone disease Guillain-Barre syndrome Polymyositis

Question 15

Why is it important to ask about loss of blood (e.g. GI, menstrual)?

Answer 15

Chronic blood loss can lead to anaemia which, in turn, leads to breathlessness

Question 16

List some differentials for sudden-onset (seconds to minutes) shortness of breath.

Answer 16

Bronchospasm (e.g. acute asthma) Anaphylaxis Laryngeal oedema PE Pneumothorax Foreign body Hysterical hyperventilation

Question 17

List some differentials for shortness of breath that occurs over hours/days.

Answer 17

Pneumonia Heart failure Pleural effusion ARDS Post-operative atelectasis

Question 18

List some differentials for gradual-onset (weeks to months) shortness of breath.

Answer 18

COPD Chronic asthma Heart failure Pulmonary fibrosis Anaemia Bronchiectasis

Question 19

Which inherited condition can cause emphysema and liver disease?

Answer 19

a1-antitrypsin deficiency

Question 20

List some signs of COPD on physical examination.

Answer 20

Chest wall deformity (e.g. barrel chest) Breathing through pursed lips Use of accessory muscles Reduced chest expansion Prolonged expiratory phase

Question 21

Which atopic conditions might a patient with asthma also suffer from?

Answer 21

Hay fever Eczema Allergies Nasal polyps

Question 22

List some drugs that exacerbate the symptoms of asthma.

Answer 22

NSAIDs Beta-blockers Aspirin

Question 23

List some signs of interstitial lung disease on physical examination.

Answer 23

Clubbing Reduced chest expansion Late inspiratory fine crackles

Question 24

List some presenting symptoms of heart failure.

Answer 24

SOBOE Orthopnoea (=SOB when lying flat) Paroxysmal nocturnal dyspnea Swollen ankles

Question 25

List some signs of heart failure on physical examination.

Answer 25

Displaces apex beat S3 and S4 heart sounds Bibasal crackles Raised JVP Hepatomegaly Peripheral oedema

Question 26

List some signs of anaemia on physical examination.

Answer 26

Cyanosis Koilonychia (if severe iron deficiency) Glossitis Angular stomatitis Conunctival pallor

Question 27

List some blood tests that would be performed when investigating a patient with possible heart failure.

Answer 27

• FBC – check for anaemia
• Cholesterol, glucose, HbA1c – major risk factors for heart failure
• TFTs – hyperthyroidism can cause high-output cardiac failure
• U&Es – baseline electrolyte levels are important, especially if diuretics are being used
• BNP – released when ventricular cells are excessively stretched (low specificity for heart failure)

Question 28

List the features of heart failure seen on CXR.

Answer 28

Alveolar shadowing Kerley B lines Cardiomegaly Upper lobe diversion Pleural effusion

Question 29

Which features of an ECG might indicate that the patient has previously suffered an MI?

Answer 29

Pathological Q waves Bundle branch block

Question 30

State two investigations that you would perform to investigate a respiratory cause of shortness of breath.

Answer 30

Peak expiratory flow rate Spirometry

Question 31

Explain why heart failure causes orthopnoea.

Answer 31

Lying down leads to increased venous return to a failing heart This leads to congestion in the pulmonary vasculature, forcing more fluid into the alveoli This leads to breathlessness

Question 32

Explain why heart failure causes bibasal crackles.

Answer 32

The increase in fluid in the lungs dilutes surfactant meaning that it is less able to keep the alveoli open Alveoli collapse Breathing in deeply makes these alveoli pop open causing the crackling sound

Question 33

Describe how acute pulmonary oedema caused by heart failure is managed.

Answer 33

Sit up Oxygen Venodilators (e.g. diamorphine, furosemide, GTN)

Question 34

Which drugs are used in the management of chronic pulmonary oedema?

Answer 34

Furosemide (loop diuretic) Spironolactone (aldosterone receptor antagonist)

Question 35

Which two physiological systems are activated in heart failure and have the potential to worsen the situation?

Answer 35

Sympathetic system Renin-Angiotensin system

Question 36

Describe the medical measures taken to combat these two systems.

Answer 36

Sympathetic system –> beta-blockers Renin-angiotensin system –> ACE inhibitors + ARBs

Question 37

What is the most common cause of heart failure?

Answer 37

Coronary artery atherosclerosis

Question 38

List some causes of post-operative breathlessness.

Answer 38

Post-operative atelectasis Pneumonia Pulmonary oedema PE Anaemia Pneumothorax

Question 39

Describe the typical presentation of asthma.

Answer 39

Intermittent episodes of reversible SOB Worse in the evenings and when exercising Associated with a dry cough Family/personal history of atopic disease

Question 40

Outline the management of asthma.

Answer 40

Avoid triggers Bronchodilation Reduce immune response in the lungs

Question 41

List some agents used as bronchodilators in asthma.

Answer 41

Beta-2 agonists (e.g. salbutamol) Anti-muscarinics (e.g. ipratropium bromide) Phosphodiesterase inhibitors (e.g. aminophylline)

Question 42

Outline the management of COPD.

Answer 42

Stop smoking Inhaled therapy (Beta-2 agonists and steroids) Pulmonary rehabilitation (physiotherapy, exercise etc.) Vaccination Non-invasive ventilation Long-term oxygen use Manage exacerbations

Question 43

Define type II respiratory failure.

Answer 43

PaO2 < 8 kPa PaCO2 > 6.5 kPa

Question 44

What is the difference between type I and type II respiratory failure?

Answer 44

T1 = a low level of oxygen in the blood (hypoxemia) without an increased level of carbon dioxide in the blood (hypercapnia), and indeed the PaCO2 may be normal or low T2 = Hypoxemia (PaO2 <8kPa) with hypercapnia (PaCO2 >6.0kPa) essentially: T1 = failure of oxygenation, T2 = failure of ventilation

Question 45

Outline the management of type II respiratory failure.

Answer 45

Controlled oxygen therapy (maintain oxygen sats 88-92%) Improve ventilation (if CO2 fails to drop with oxygen therapy) Treat underlying cause

Question 46

Describe the typical presentation of Pneumocystic jiroveci pneumonia.

Answer 46

Dry cough, SOB, desaturation on exercise, diffuse interstitial shadowing on CXR NOTE: tends to be in young patients from Africa

Question 47

Which tests should you perform if Pneumocystic jiroveci pneumonia is suspected?

Answer 47

HIV TB

Question 48

List some causes of interstitial lung disease.

Answer 48

• Congenital – neurofibromatosis, Gaucher disease
• Systemic inflammatory disease – rheumatoid arthritis, ankylosing spondylitis, sarcoidosis
• Chemicals – asbestos, silica
• Drugs – methotrexate, amiodarone, nitrofurantoin, cicosporin
• Hypersensitivity – Bird-fancier’s lung
• Radiation
• Idiopathic

Question 49

What are Reed-Sternberg cells?

Answer 49

Binucleate lymphocytes – associated with Hodgkin’s lymphoma

Question 50

What is Eisenberg’s syndrome?

Answer 50

Where L-R cardiac shunt becomes R-L - In ASD and PDA - Results in PHT - Increased MR in pregnant women

Question 51

DDx for bi-basal crepitations and how would you differentiate between the causes?

Answer 51

FINE - ILD: reduced chest expansion, clubbing COURSE - Pneumonia: acute productive cough, fever, chest pain, dull percussion note - Bronchiectasis: chronic productive cough, wheeze, clubbing - Pulmonary oedema: raised JVP, pedal oedema, orthopnoea, hx of IHD

Question 52

What is your ddx for SOB post-op? How can you differentiate them?

Answer 52

• Pulmonary Oedema
• PE
• Atelectasis
• Pneumonia (aspiration)
• Pneumothroax