Shortness of Breath Flashcards
List some broad mechanisms that can lead to shortness of breath. Give an example of a disease that falls under each of these mechanisms.
Insufficient oxygen entering the lungs – COPD
Insufficient oxygen entering the blood - emphysema
Insufficient oxygen reaching the tissues - anaemia
Increased respiratory drive - acidaemia
Which diseases can cause an inability to fully inflate the lungs?
Increased work – due to obesity and stiffness due to interstitial lung disease
Weak respiratory muscles – Guillain-Barre syndrome, myasthenia gravis
Hyperinflated lungs – COPD
Which diseases can cause insufficient oxygen to be delivered across the body?
Anaemia
Reduced cardiac output (e.g. heart failure, aortic stenosis)
Shock (e.g. sepsis, hypovolaemia)
What are two important features of the history of presenting complaint of a patient presenting with shortness of breath?
Time of onset
Alleviating/exacerbating factors
When does asthma tend to get worse?
At night
On exercise
On exposure to triggers (e.g. the cold)
List some important risk factors that are associated with various causes of shortness of breath.
Smoking Pets Occupational history Medications Past medical history
Which occupational disease is associated with chronic dust inhalation?
Pneumoconiosis
List some drugs that are associated with interstitial lung disease.
Methotrexate
Amiodarone
Nitrofurantoin
List some autoimmune diseases that are associated with interstitial lung disease.
Rheumatoid arthritis
Sarcoidosis
SLE
List some important associated symptoms that you should enquire about in a patient presenting with shortness of breath.
Cough (and haemoptysis) Chest pain Muscular weakness or fatigue Tender limbs Weight loss, loss of appetite, night sweats Fever Loss of blood
Describe the pattern of cough in:
Pneumonia
Chronic bronchitis
Asthma
- 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
List some causes of blood-stained sputum.
Cavitating pneumonia
PE
Lung cancer
Bronchiectasis
List some diseases that cause pleuritic chest pain and shortness of breath.
Pneumonia
PE
Pneumothorax
Which differentials would you consider if a patient complains of shortness of breath and muscle weakness/fatigue?
Myasthenia gravis Lambert-Eaton syndrome Motor neurone disease Guillain-Barre syndrome Polymyositis
Why is it important to ask about loss of blood (e.g. GI, menstrual)?
Chronic blood loss can lead to anaemia which, in turn, leads to breathlessness
List some differentials for sudden-onset (seconds to minutes) shortness of breath.
Bronchospasm (e.g. acute asthma) Anaphylaxis Laryngeal oedema PE Pneumothorax Foreign body Hysterical hyperventilation
List some differentials for shortness of breath that occurs over hours/days.
Pneumonia Heart failure Pleural effusion ARDS Post-operative atelectasis
List some differentials for gradual-onset (weeks to months) shortness of breath.
COPD Chronic asthma Heart failure Pulmonary fibrosis Anaemia Bronchiectasis
Which inherited condition can cause emphysema and liver disease?
a1-antitrypsin deficiency
List some signs of COPD on physical examination.
Chest wall deformity (e.g. barrel chest) Breathing through pursed lips Use of accessory muscles Reduced chest expansion Prolonged expiratory phase
Which atopic conditions might a patient with asthma also suffer from?
Hay fever
Eczema
Allergies
Nasal polyps
List some drugs that exacerbate the symptoms of asthma.
NSAIDs
Beta-blockers
Aspirin
List some signs of interstitial lung disease on physical examination.
Clubbing
Reduced chest expansion
Late inspiratory fine crackles
List some presenting symptoms of heart failure.
SOBOE
Orthopnoea (=SOB when lying flat)
Paroxysmal nocturnal dyspnea
Swollen ankles
List some signs of heart failure on physical examination.
Displaces apex beat S3 and S4 heart sounds Bibasal crackles Raised JVP Hepatomegaly Peripheral oedema
List some signs of anaemia on physical examination.
Cyanosis Koilonychia (if severe iron deficiency) Glossitis Angular stomatitis Conunctival pallor
List some blood tests that would be performed when investigating a patient with possible heart failure.
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)
List the features of heart failure seen on CXR.
Alveolar shadowing Kerley B lines Cardiomegaly Upper lobe diversion Pleural effusion
Which features of an ECG might indicate that the patient has previously suffered an MI?
Pathological Q waves
Bundle branch block
State two investigations that you would perform to investigate a respiratory cause of shortness of breath.
Peak expiratory flow rate
Spirometry
Explain why heart failure causes orthopnoea.
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
Explain why heart failure causes bibasal crackles.
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
Describe how acute pulmonary oedema caused by heart failure is managed.
Sit up
Oxygen
Venodilators (e.g. diamorphine, furosemide, GTN)
Which drugs are used in the management of chronic pulmonary oedema?
Furosemide (loop diuretic)
Spironolactone (aldosterone receptor antagonist)
Which two physiological systems are activated in heart failure and have the potential to worsen the situation?
Sympathetic system
Renin-Angiotensin system
Describe the medical measures taken to combat these two systems.
Sympathetic system –> beta-blockers
Renin-angiotensin system –> ACE inhibitors + ARBs
What is the most common cause of heart failure?
Coronary artery atherosclerosis
List some causes of post-operative breathlessness.
Post-operative atelectasis Pneumonia Pulmonary oedema PE Anaemia Pneumothorax
Describe the typical presentation of asthma.
Intermittent episodes of reversible SOB
Worse in the evenings and when exercising
Associated with a dry cough
Family/personal history of atopic disease
Outline the management of asthma.
Avoid triggers
Bronchodilation
Reduce immune response in the lungs
List some agents used as bronchodilators in asthma.
Beta-2 agonists (e.g. salbutamol)
Anti-muscarinics (e.g. ipratropium bromide)
Phosphodiesterase inhibitors (e.g. aminophylline)
Outline the management of COPD.
Stop smoking
Inhaled therapy (Beta-2 agonists and steroids)
Pulmonary rehabilitation (physiotherapy, exercise etc.)
Vaccination
Non-invasive ventilation
Long-term oxygen use
Manage exacerbations
Define type II respiratory failure.
PaO2 < 8 kPa
PaCO2 > 6.5 kPa
What is the difference between type I and type II respiratory failure?
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
Outline the management of type II respiratory failure.
Controlled oxygen therapy (maintain oxygen sats 88-92%) Improve ventilation (if CO2 fails to drop with oxygen therapy) Treat underlying cause
Describe the typical presentation of Pneumocystic jiroveci pneumonia.
Dry cough, SOB, desaturation on exercise, diffuse interstitial shadowing on CXR
NOTE: tends to be in young patients from Africa
Which tests should you perform if Pneumocystic jiroveci pneumonia is suspected?
HIV
TB
List some causes of interstitial lung disease.
Congenital – neurofibromatosis, Gaucher disease
Systemic inflammatory disease – rheumatoid arthritis, ankylosing spondylitis, sarcoidosis
Chemicals – asbestos, silica
Drugs – methotrexate, amiodarone, nitrofurantoin
Hypersensitivity – Bird-fancier’s lung
Radiation
Idiopathic
What are Reed-Sternberg cells?
Binucleate lymphocytes – associated with Hodgkin’s lymphoma
