Respiratory Flashcards
Give some red flags for a respiratory history/examination
- Haemoptysis/brown sputum
- Weight loss
- Cough >3 weeks
- Chest pain
- Drenching night sweats
- Foreign travel
- Smoking history
- Sudden onset SOB
- Risk factors for PE
What is the most common lung disease in the UK?
Asthma
Give the 3 mechanisms behind airway narrowing in asthma
- Bronchial muscle contraction
- Inflammation caused by mast cell degranulation
- Increased mucus production
Asthma often shows a diurnal variation. What does that mean?
symptoms often worse in morning
Describe the percussion in asthma
Hyperresonance (due to presence of air)
Describe the inflation of the lungs in acute asthma
Hyperinflation
Describe the auscultation of the lungs in asthma
Bilateral decreased air entry
Wheeze
Are the symptoms/signs in asthma bilateral or unilateral?
Bilateral
What is a ‘silent chest’ in asthma a sign of?
Severe illness - life-threatening
What is the diagnostic investigation in asthma?
Spirometry
How does spirometry and PEFR differ?
Both tests measure the speed and efficiency with which air moves in and out of the lungs.
Spirometry - offers a larger set of parametric values regarding lung health than a peak flow meter does and requires a patient to perform specific breathing manoeuvres using a spirometer.
PEFR - can be performed at bedside/patient home
What spirometry result indicates asthma?
FEV1/FVC <0.7 (70%) indicates obstructive airway disease
What is the FEV1/FVC ratio?
The FEV1/FVC ratio is the ratio of the forced expiratory volume in the first one second to the forced vital capacity of the lungs (i.e. indicates how much air you can forcefully exhale)
Measured by spirometry
Give some other investigations that can be used in chronic asthma?
- Fractional exhaled nitric oxide (FeNO)
- Bronchodilator reversibility tests
- Skin prick test - confirm atopy
What bronchodilator reversibility test result indicates asthma?
Improvement of FEV1 >12% after bronchodilator therapy is diagnostic
What is the stepwise pharmacological long-term management of asthma
- Short-acting b2 agonist (SABA) e.g. salbutamol
- Add inhaled low dose inhaled corticosteroid (ICS) e.g. beclomethasone
- Add long-acting b2 agonist e.g. salmeterol
- Two options:
- Increase ICS dose
- Add leukotriene receptor antagonist e.g. montelukast
What are the aims of pharmacological management of asthma?
- No daytime symptoms
- No night-time waking due to asthma
- No asthma attacks
- No limitations on activity including exercise
- Minimal side effects from medication
Pathophysiology behind an asthma attack?
IgE type 1 hypersensitivity reaction leading to smooth muscle contraction, bronchial oedema and mucus plugging.
What medications can exacerbate asthma?
- Beta blockers e.g. bisoprolol → contraindication
- NSAIDs (some but not all) → caution
- AChEIs –> due to increased bronchial secretions
Give some triggers for an asthma attack
- Exposure to allergens e.g. dust, pollution, animal hair or smoke
- URT or LRTIs
- Cessation or reduction of asthma medications
- Concomitant medications e.g. beta blockers, NSAIDs
- Triggers e.g. exercise, cold air
Give some signs of an acute asthma attack
- Use of accessory muscles of respiration
- Hyperinflation of the chest
- Tachypnoea
- Tachycardia
- Diaphoresis (sweating)
Give some signs of a severe asthma attack
- Inability to speak in full sentences
- RR >25
- Peak flow 33-50% predicted
Give some signs of a life-threatening asthma attack
- PEFR <33% predicted
- O2 sats <92%
- Silent chest on auscultation
- Confusion
- Bradycardia
- Hypotension
- Cyanosis
- Exhaustion – weak or no respiratory effort
What may bradycardia in a life-threatening asthma attack indicate?
Impending respiratory arrest
What does an FeNO test indicate?
Measures level of NO in breath which is a sign of inflammation in your lungs
Which bloods are important in acute asthma?
- FBC – infection
- CRP – infection
- Eosinophil count
- Total IgE
- IgE to aspergillus
Which imaging is 1st line in acute asthma?
CXR - but doesn’t delay management
What may a CXR in acute asthma show?
usually normal (may show hyperinflation or bronchial wall thickening)
Give the stepwise pharkmacological management in an acute asthma attack (ABCDE)
- Oxygen
- Nebulised salbutamol (high dose)
- Nebulised ipratropium bromide if needed
- Steroid therapy - oral prednisolone or IV hydrocortisone
- IV Magnesium sulphate
- IV aminophylline
When would ipratropium bromide be given in acute asthma? What is the effect of this?
Add for patients with acute severe or life-threatening asthma or to those with a poor initial response to b2 agonist therapy.
Combining nebulised ipratropium bromide with a nebulised b-2 agonist produces significant bronchodilation than a b-2 agonist alone.
Who should steroid therapy be administered to in patients presenting with an acute asthma attack?
ALL patients with acute asthma
What steroids should be used in acute asthma?
Oral prednisolone 40-50mg
If oral route unavailable (likely) → IV hydrocortisone
How long should oral prednisolone be continued for following an acute asthma attack?
5 days or until full recovery
When would you consider giving IV magnesium sulphate in acute asthma?
- Acute severe asthma who have not had a good response to inhaled therapy
- Life-threatening or near-fatal asthma
- Only use after consultation with senior medical staff
What would reduced air entry in acute asthma indicate?
significant airway compromise
What would absent air entry on auscultation in acute asthma indicate?
Underlying pneumothorax
What would dullness on percussion in acute asthma indicate?
Pleural effusion
Lobar collapse
Typical ABG results in acute asthma?
Low PaO2, low PaCO2
If PaCO2 normal or raised → major concern
What is COPD?
A triad of chronic bronchitis, emphysema and small airway fibrosis causing irreversible obstruction of air flow; bronchitis or emphysema can be the predominant condition.
Most common cause of COPD?
Smoking (95%)
Other causes of COPD?
- Dust, silica, pollutants
- Alpha 1 antitrypsin deficiency (a-1 is a protease inhibitor)
- Autosomal dominant
- Raises risk for lung and liver disease
COPD is usually a combination of chronic bronchitis and emphysema. What are these 2 conditions?
‘Chronic bronchitis’ - chronic inflammation of the bronchi (usually defined as a productive cough on most days for 3 months a year over 2 successive years)
‘Emphysema’ - enlargement of air spaces in the terminal bronchioles leading to inefficient gas exchange ratios and poor air outflow
What is the pathogenesis behind COPD?
Chemicals and heat trigger inflammation in bronchi and lung parenchyma
- Bronchi → persistent inflammation leads to scarring and mucus hyperplasia (bronchitis)
- Parenchyma → inflammation leads to alveolar wall loss (emphysema)
Give some triggers for COPD exacerbations
- Viral or bacterial lung infection (acute bronchitis or pneumonia)
- Smoking
- Exposed to smoke or air pollution
Give some symptoms of COPD
- Dyspnoea (may only happen at first when exercising)
- Chronic productive cough (sputum usually colourless, may become green in LRTIs)
- Recurrent LRTIs
- Fatigue
- Headache (due to CO2 retention)
- Trouble taking a deep breath
- Chest tightness
Give some symptoms of an exacerbation of COPD
- More coughing, wheezing, or SOB than usual
- Changes in colour, thickness or amount of mucus
- Feeling tired for more than 1 day
- Swelling of legs or ankles
- O2 levels lower than normal
- Severe → cyanosis, severe SOB, chest pain, confusion
What signs are seen in a COPD exacerbation?
- Accessory muscle use & pursed lips
- Tachypnoea
- Hyperinflation
- Reduction of cricosternal distance
- Reduced chest expansion
- Hyper resonant percussion
- Decreased/quiet breath sounds
- Wheeze on auscultation (due to inflammatory airway oedema and mucous obstruction)
- Cyanosis
- Cor pulmonale (signs of RHF)
- CO2 retention flap
- Reduced conscious level
- Severe → tachycardia, tachypnoea, hypoxia, cyanosis, reduced consciousness
What is the typical spirometry finding in COPD?
FEV1/FVC <0.7
What SpO2 should you aim for in COPD patients?
88-92%
How can COPD affect the heart?
COPD can cause low oxygen levels in the blood, thereby placing additional stress on the heart.
This can lead to right ventricle hypertrophy and potentially cor pulmonale
What is cor pulmonale?
Cor pulmonale is a condition that causes the right side of the heart to fail.
Long-term high blood pressure in the arteries of the lung and right ventricle of the heart can lead to cor pulmonale
What may an FBC show in COPD?
Raised MCV - polycythaemia
What may an ABG show in COPD?
Low PaO2
Raised PaCO2 (type 2 respiratory failure)
What is the purpose of a sputum sample in COPD exacerbation?
Enables targeted antibiotic therapy
What may a CXR show in COPD
- Hyperinflated chest (>6 anterior ribs)
- Bullae
- Decreased peripheral vascular markings
- Flattened hemidiaphragms
How should oxygen be delivered to COPD patients during acute exacerbations?
Use a venturi mask and titrate oxygen appropriately.
If the patient is conscious, sit them upright as this can also help with oxygenation.
Give the pharmacological management of an acute COPD exacerbation
- Oxygen
- Nenuclised salbutamol
- Nebulised ipratropium bromide
- Steroids
What steroids should be used in the management of a COPD exacerbation?
Oral prednisolone (IV hydrocortisone if needed)
Give the stepwise pharmacological management of chronic COPD
Step 1 – Short acting B2-agonist (SABA) OR short acting muscarinic antagonist (SAMA)
Step 2 – Add LABA AND LAMA
Step 3 – LAMA + LABA + ICS
What can lung cancers be divided into?
Small cell & non small cell tumours
Are small cell or non small cell lung cancers more common?
Non-small cell (80%)
What is the most common type of NSCLC?
Adenocarcinoma (40%)
What is the 2nd most common type of NSCLC?
Squamous cell carcinoma (20%)
Give some red flag symptoms for lung cancer
- Cough
- Haemoptysis
- Dyspnoea
- Chest pain
- Weight loss
- N&V
- Anorexia
Lung cancer can present with Horner’s syndrome. Give the location of the tumour in this instance
Apical → interrupted sympathetic supply to face
Lung cancer can lead to many complications.
What chest signs could be seen during an examination?
- Consolidation – pneumonia
- Collapse – absent breath sounds, ipsilateral tracheal deviation
- Pleural effusion – stony dull percussion, decreased vocal resonance and breath sounds
Are SCLCs or NSCLCs more likely to cause paraneoplastic syndromes?
SCLCs
Give some paraneoplastic syndromes that can be caused by lung cancer
- Cushing’s syndrome → ectopic ACTH secretion
- SIADH → ectopic SIADH syndrome
- Lambert-Eaton syndrome
- Hyperparathyroidism
How does parathyroid hormone affect calcium?
parathyroid hormone stimulates the release of calcium from large calcium stores in the bones into the bloodstream (hyperparathyroidism → hypercalcaemia)
Give the pathology behind lung cancer manifesting as SOB
If cancer invades major airways
Give the pathology behind lung cancer manifesting as haemoptysis
Invasion of cancer into airways (friable tissue) may lead to bleeding
Give the pathology behind lung cancer manifesting as pain
Local invasion affecting the lining of the pleural cavity or bone, causing pain
Give the pathology behind lung cancer manifesting as a pleural effusion
Can cause inflammatory reactions which can leads to the accumulation of fluid in the pleural space
Give the pathology behind lung cancer manifesting as a superior vena cava obstruction
Cancer may invade into surrounding lung tissues, leading to compression of the draining of the SVC leading to dyspnoea and facial plethora due to venous congestion
Give the pathology behind lung cancer manifesting as a pneumothorax
Invasion of the tumour may lead to a communication between the lung parenchyma and the pleural cavity, resulting in the collapse of the lung
Give the pathology behind lung cancer manifesting as atelectasis
Invasion may lead to total obstruction of the airway leading to collapse of that lobe
What is the 1st line investigation in suspected lung cancer?
CXR
Is pleural effusion typically unilateral or bilateral in lung cancer?
Unilateral
Give some potential CXR features in lung cancer
- Nodules
- Hilar enlargement
- Lung collapse
- Pleural effusion – usually unilateral in cancer
- Consolidation
- Peripheral opacity – a visible lesion in the lung field
- Bony metastases
What staging system is used to stage lung cancer?
TNM
What investigation can be used in the staging of lung cancer?
CT scan of chest, abdomen and pelvis