Respiratory Flashcards
What 2 conditions make up COPD?
- chronic bronchitis
- emphysema
What is COPD?
- non-reversible long term deterioration in air flow through the lungs
- caused by damage to lung tissue
- SOB and prone to infection
- not reversible with bronchodilators
- exacerbations occur → if due to infection, these are called IE COPD
What are the classic presenting features of COPD?
- long term smoker
- SOB
- cough
- sputum production
- wheeze
- recurrent respiratory infections
How do you classify COPD?
MRC dyspnoea scale
- breathless on strenuous exercise
- breathless on walking up hill
- breathless that slows on flat
- stop to catch breath after 100m walking on flat
- unable to leave house due to breathlessness
Risk factors for COPD
- smoking
- 40-60
- secondhand smoke exposure
- occupational exposure → mining, dust, cotton, wood
- pollution → heating fuel, outdoor pollutants
- alpha-1-antitrypsin deficiency
Why is A1AT implicated in COPD?
- protein made by liver
- protects lung from damage
- deficiency can lead to earlier onset and increased severity of COPD
Diagnosis of COPD
- clinical presentation
- spirometry
What can be seen in COPD spirometry?
- shows obstructive picture
- lung capacity > ability to forcefully expire air quickly
- FEV1/FVC <0.7
- does not respond to reversibility testing with SABA
- severity of obstruction can be measure using FEV1
- compare patient to predicted
What other tests can be done for COPD?
- chest xray → exclude others
- FBC
- BMI
- ECG
- serum A1AT
What is emphysema?
Symptoms
- dyspnoea/tachypnoea
- minimal cough
- pink skin, pursed lip breathing
- accessory muscle use
- cachexia
- hyperinflammation → barrel chest
- weight loss
complications = pneumothorax due to bullae
What is chronic bronchitis?
symptoms
- chronic productive cough → purulent sputum
- dyspnoea
- cyanosis = hypoxaemia
- peripheral oedema
- obesity
- haemoptysis
General management of COPD
- stop smoking
- pneumococcal vaccine
- annual flu vaccine
Stepwise management of COPD
- SABA or SAMA
- if no asthmatic/steroid response → LABA/LAMA, if asthmatic/steroid response → LABA, ICS
- long term oxygen therapy
Presentation of IE COPD
- acute worsening of symptoms
- SOB, sputum, wheeze
- usually triggered by infection
Investigations for IE COPD
- ABG
- chest xray
- sputum culture and sensitivities for Ab therapy
- FBC and U&E
What does ABG show in IE COPD
- CO2 retention = acidosis
- are they in type 1 or 2 RF
normal pCO2 and low pO2 = T1RF
raised pCO2 and low pO2 = T2RF
Management of IE COPD
- steroids AND
- nebulised bronchodilators
- Abs
- physiotherapy → sputum clearance
- if severe = IV aminophylline (bronchodilator), NIV (CPAP/BIPAP)
What bronchodilators are used in IE COPD?
- salbutamol
- ipratropium bromide
How does A1AT deficiency affect the lungs and liver?
lungs
- lack of normal A1AT
- excess protease enzymes → attack lung tissue
liver
- mutant A1AT builds up
- tissue damage → cirrhosis → HCC
Signs and symptoms of A1AT deficiency
lungs
- COPD symptoms
liver
- loss of appetite
- weight loss
- oedema
- jaundice
- haematemesis
Diagnosis of A1AT deficiency
- low serum A1AT
- liver biopsy
- A1AT mutant gene
- CT thorax
Management of A1AT
- no cure
- stop smoking
- symptomatic treatment
- organ transplant for end-stage liver/lung disease
- monitor for HCC
What is asthma?
- chronic inflammatory condition
- episodes of reversible airway obstruction due to:
bronchoconstriction
excessive secretion production
Causes of asthma
hypersensitivity of the airways triggered by:
- cold air, exercise
- cigarette smoke
- air pollution
- allergens → pollen, cats, dogs, horses, mould
- time of day → early morning, night
Presentation of asthma
episodes of
- wheeze → widespread, polyphonic
- breathlessness
- chest tightness
- dry cough
- family/personal history of atopy = eczema, asthma, hayfever
- diurnal variability
Investigations for asthma
spirometry with reversibility testing
- obstructive pattern
- FEV1 <80% of predicted normal
- FEV1/FVC ratio <0.7
peak flow measurement
Treatment for asthma
- SABA eg salbutamol
- inhaled corticosteroid eg budesonide
- leukotriene receptor antagonist eg montelukast
- LABA eg salmeterol
- increase ICS dose
Epidemiology of TB
- majority of cases in Africa and Asia
- cause of death for most people with HIV
Features of TB
- aerobic, non-motile, non-sporing, slightly curved bacilli with a thick waxy capsule
- acid-fast bacilli → turns red/pink with Ziehl-neelsen stain
- slow growing
- resistant to phagolysosomal killing
- able to remain dormant
Pathophysiology of TB
spread via respiratory droplets → airborne infection
- alveolar macrophages ingest bacteria and rods proliferate inside
- drain into hilar lymph nodes
- delayed hypersensitivity reaction
- tissue necrosis and granuloma formation = caseating
- primary ghon focus
- ghon complex = ghorn focus and lymph nodes
Systemic symptoms of TB
- low grade fever
- anorexia
- drenching night sweats
Pulmonary symptoms of TB
- productive cough
- haemoptysis
- cough >3 weeks (dry or productive)
- breathlessness
- sometimes chest pain
Signs of TB
- signs of bronchial breathing
- dulness to percuss
- decreased breathing
- fever
- crackles
What are signs of bronchial breathing?
- loud harsh breathing sounds
- mid range pitch
Investigations for TB
- chest xray → fibronodular opacities on upper lobes
- sputum culture for acid-fast bacilli → ZN stain on Lowenstein-Jensen agar
- biopsy → caseating granuloma