Obstructive Lung Diseases Flashcards
COPD is an umbrella term for what two disorders?
Bronchitis + emphysema
Presentation of COPD:
- Breathlessness exertional or at rest?
- Cough productive or non-productive?
Exertional breathlessness
Productive cough
What is the appearance of COPD on CXR?
Hyperinflated lungs or normal lung fields
(CXR done to exclude other pathologies)
(May also see bullae or flat hemidiaphragm)
What is polycythaemia and how it is connected with COPD?
Polycythaemia = high RBC concentration (high Hb)
Secondary polycythaemia is a complication of COPD due to excess erythropoetin production due to chronic hypoxaemia
What is the 1st line, 2nd line and 3d line management of COPD?
1st line smoking cessation + SABA or SAMA 2nd line - if no asthmatic features LABA + LAMA combination - if asthmatic features LABA + ICS 3rd line LABA + LAMA + ICS
Are COPD exacerbations mainly bacterial or viral?
Mainly viral eg rhinovirus
How can COPD lead to cor pulmonale
Chronic hypoxaemia > pulmonary hypertension > RV hypertrophy > cor pulmonale
What investigations should be done in hospital for a COPD exacerbation?
CXR + ABG + bloods + ECG + sputum culture
What is the commonest organism in bacterial COPD exacerbations?
Haemophilus influenzae
Are antibiotics given routinely for COPD exacerbations?
No - only if increased sputum purulence or clinical signs of pneumonia eg pyrexia
What is the management of a COPD exaceration?
30mg oral prednisolone OD for 5 days
Increase frequency of bronchodilator use (consider using nebulizer)
Antibiotics if suspect bacterial cause
Continue usual inhalers throughout
What method of breathing assistance is used for acute on chronic type 2 respiratory failure?
Non invasive ventilation NIV
Some COPD patients lose their _____ drive and rely on their _____ drive, meaning they can tolerate lower _____, for these patients if you give too much oxygen is can cause _____
Some COPD patients lose their HYPERCAPNIC drive and rely on their HYPOXIC drive, meaning they can tolerate lower OXYGEN SATURATIONS, for these patients if you give too much oxygen is can cause RESPIRATORY DEPRESSION
What type of oxygen delivery is used 1st line for patients who’ve lost their hypercapnic drive?
Venturi mask
2nd line NIV if CO2 still creeping up
What are the indications for long term oxygen therapy in COPD?
PaO2 <7.3 on 2 occasions despite maximal treatment and non-smoker
What type hypersensitivity is asthma? Which type of immunoglobulin is involved?
Type I hypersensitivity
IgE mediated
What is the basic pathophysiology of asthma?
Recurrent reversible airway obstruction
What is Samter’s triad?
Asthma + aspirin insensitivity + nasal polyps
Describe the wheeze in asthma
Expiratory polyphonic wheeze
Describe the pattern of symptoms in asthma
Diurnal variation - worse at night
Variability in symptoms
Can asthma cause a cough?
Yes
What is the 1st line investigation for asthma?
In those aged 5-17 what investigation is performed first?
In those aged 17+ what investigation is performed first?
Spirometry
Aged 5-17 - spirometry
Aged 17+ - exhaled nitric oxide FeNO test
What is spirometry? What does it measure?
Lung function test to measure FEV1, FVC and VC
Differentiates obstructive and restrictive lung diseases
What is peak flow?
Using a peak flow device measures how quickly you can blow air out lungs
When investigating asthma, patients are recommend to monitor their own peak flow, for how long should they do this and what is a positive sign?
Monitor peak flow for 2-4wk
Positive is diurnal variability greater than 20%