COPD Flashcards
What are the general obstructive diseases?
Bronchial asthma, chronic bronchitis, emphysema
What other diseases cause secondary obstruction?
Lung cancer, tumours, foreign objects, bronchiectasis and TB
What is COPD?
Chronic obstructive pulmonary disease, involves chronic bronchitis and emphysema
What is average normal peak respiratory flow rate?
400-600 ml/min, in obstruction can fall to 50% or less
What are the risk factors for COPD?
genetics such as alpha -1- antitrypsin deficiency , atmospheric pollution, smoking, passive smoking, maternal smoking, certain occupations, infections, chronic asthma
What does alpha -1 antitrypsin deficiency cause?
It causes emphysema.
What is chronic bronchitis?
Inflammation of the mucous membranes, it can lead to excess mucus to be produced
What is the definition of chronic bronchitis?
Cough productive sputum, for at least 3 consecutive months for more than 2 consecutive years
What is complicated chronic bronchitis ?
mucopurulent (yellow or green sputum) or when TEV1 falls
What immune cells are present in chronic bronchitis?
neutrophils
Describe the changes in small airways
Goblet cells where they have not been before, significant inflammation and fibrosis
Describe the changes in large airways
mucous glands hyperplasia, goblet cells hyperplasia, inflammation and fibrosis is minor
What are the signs of chronic bronchitis ?
inspiratory stridor, increased respiratory rate, decreased chest expansion, lungs are hyperinfalted
What are the symptoms of chronic bronchitis ?
breathlessness, cough , sputum
What are the investigations?
Chest X ray, spirometry, full blood count, ECG
What is the treatment of chronic bronchitis?
Corticosteroids, antibiotics in infection is present, O2 therapy if necessary
What is acute bronchitis?
It is caused by H influenzae, S pneumoniae, it is usually self limiting
What is emphysema?
Obstructive disease in which the alveoli get bigger as the elastic fibres get destroyed, the loss of septa between alveoli
What are the different types of emphysema ?
Centriacinar, periacinar, panacinar
What is centriacinar emphysema?
It occurs close to respiratory bronchioles, in the central acinus which its he most vulnerable as the particles get deposited in here. It usually occurs predominantly in upper part of the lungs, worst at the apex of upper and middle lobe as the clearance is worst in here due to reduced blood flow
In which parts of lungs is the centriacinar emphysema the worst?
In the apex of the upper and lower lobes as there is reduced blood flow and therefore clearance
Which part of lungs does centriacinar emphysema affect ?
Upper part of lungs
What is panacinar emphysema?
Destruction of whole acinus, forms mostly in the lower parts of the lungs, commonly in patients with alpha 1 antitrypsin deficiency
Which part of the lungs does panacinar emphysema affect mostly ?
The lower part of the lungs
What is periacinar emphysema?
Occurs along the edges of the acing unit, against fixed structures, forms blebs or bulla, can cause pneumothroax
What are the other types of emphysema?
scar irregular emphysema, bullous emphysema (large bulla at the centre)
What is the effect of smoking?
It increases release of damaging enzymes proteases and interferes with anti-elastase mechanism and repair mechanism
What are the signs of emphysema?
expiratory wheeze, increased respiratory rate, decreased chest expansion, hyperinflantion and CO2 flapping tremor
What are the symptoms of emphysema?
Breathlessness, cough and pursed lips
What are the investigations for emphysema?
Chest X ray, full blood count, spirometry, ECG
What is the treatment of emphysema?
Anti-tryspsin replacement, bronchodilators, O2 therapy if needed
What is the difference between asthma and COPD ?
Asthma is variable and reversible, whereas COPD is usually deteriorating with time and is irreversible
What is the reversible component of COPD?
Inflammation and smooth muscle constriction
What is the irreversible component of COPD ?
Loss of tissue and fibrosis
What are the 4 mechanisms that contribute to hyperaemia in COPD ?
Ventillation/perfusion ratio, alveolar hypoventilation, diffusion impairment, shunt
What is the difference between V/Q mismatch and shunt?
In V/Q mismatch there is some ventilation to the alveoli, so soma gas exchange takes place. In shunt there is no ventilation to these alveoli and therefore administering O2 will have no effect.
What are the vascular changes on hypoxia?
Pulmonary vasoconstriction, to prevent blood flow to the alveoli that are not well ventilated, redirecting blood to alveoli that are well ventilated
What is for pulmonale?
Hypertrophy of right ventricle, this happens as a result of pulmonary vasoconstriction, there is bigger resistance to blood flow and heart muscles have to work harder to pump the blood around pulmonary circulation
Describe pulmonary hypertension
There is increased pressure in pulmonary vessels, the resistance to blood flow is increased, there is persistent constriction of smooth muscles which can lead to fibrosis
What is secondary polycytheamia ?
Production of more RBC as a result to hypoxia
What is the difference between COPD and asthma?
CODP is chronic, slowly progressing, mostly irreversible, neutrophilic as opposed to lymphocytes in asthma
What are the main pathologies in COPD?
Airways thickening, loss of elastic tissue this less and bigger alveoli, accumulation of mucus, it is neutrophilic
What is one pack year?
Smoking 1 pack everyday for one year
What is the COPD provenance in terms of pack years?
More than 20 pack years
What is the rate of decline of FEV1 in smokers and non-smokers?
30 ml/year for non-smoker and 50 ml/year for smoker, the rate of decline is 3 times higher, the decline also starts earlier
What is the normal and abnormal alpha -1- antitrypsin genotype?
Normal PiMM, abnormal PiZZ
What are the differential diagnoses?
Asthma, lung cancer, TB, bronchiectasis, pulmonary emboli, fibrosing alveolitis
What are the symptoms of COPD?
breathlessness, cough and sputum
What are the signs of COPD?
Dyspnoea, wheeze, peripheral oedema, pursed lips, cyanosis with flapping tremor, hyper expanded chest, reduced expansion, laryngeal descend, decreased breath sounds, prolonged expiration with where, paradoxical movement of abdomen, if for pulmonate is present there is increased JVP, oedema, hepatomegaly, ascites
Give the stages of COPD and the signs
moderate FEV1 50-79% dyspnoea on exertion, cough
severe 30-49 % dyspnoea on mild exertion, cough and sputum
very severe less than 30%, wheeze, cough, dyspnoea on rest, cor pulmonale
What are the possible investigations?
Spirometry, lung function test, CO gas transfer, bronchodilator reversibility, chest X ray, full blood count, blood gases, ECG, sputum analysis, measure alpha -1- antitrypsin deficiency
What is acute exacerbation of COPD?
Usually due to viral or bacterial infection, but also possibility of pneumothorax, trauma, presents with increased sputum production and cough, sputum is purulent, pyrexia, unable to sleep, confusion, drowsiness, cyanosis, flapping tremor, oedema
What is the management of COPD?
Bronchodilators, anti-inflammatory drugs, diuretics, vaccinations, pulmonary rehabilitation, antibiotics, corticosteroids, respiratory stimulant, O2 therapy and non-invasive ventilation at later stages
What are the two main symptoms of COPD?
Breathlessness and cough
What is MRC scale?
It is a scale for dyspnoea, it has 5 grades
