Respiratory Flashcards
what two types of disease are included within the definition of COPD?
emphysema and chronic bronchitis it’s chronic obstruction with *irreversible airflow obstruction –> air trapping and hyperinflation
define chronic bronchitis
narrowing of airways and mucosal oedema –> mucus hypersecretion –> cough + excessive mucus = persistent cough+mucus for 3/12 for 2 consecutive years
list some features that would suggest it is more likely the patient has COPD than asthma
onset >35yo, smoking/pollution related, chronic dyspnoea (instead of attacks), sputum production, lack of diurnal FEV1 variation
give 2 causes of COPD
**smoking, occupational exposure (particles and gases) alpha-1 antitrypsin deficiency
what generally causes early-onset COPD?
alpha-1 antitrypsin deficiency - produced in liver.
give 3 risk factors of COPD
smoking, pollutant exposure, frequent lower resp infections in childhood, age.
describe the pathology seen in chronic bronchitis
narrow airways. hypertrophy and hyperplasia of mucus secreting glands of the bronchial tree. bronchial wall inflammation. mucosal oedema. ulceration of epithelial layer - heals squamous instead of columnar (squamous metaplasia).
describe the pathology seen in emphysema
elastin breakdown –> dilation and destruction of alveoli - expiratory airflow limitation and air trapping
which disease is predominant in each of pink puffers and blue bloaters?
pink puffers = predominantly emphysema blue boaters = predominantly chronic bronchitis
what are the features of a pink puffer?
increased alveolar ventilation -= nearly normal PaO2 + normal/low PaCO2 - breathless but not cyanosed - may progress to type 1 resp failure they retain CO2 making it normal, will be old and thin, using accessory muscles
what are the features of a blue bloater?
decreased alveolar ventilation - low PaO2 and high PaCO2 - cyanosed but not breathless - poss. cor pulmonale - rely on hypoxic drive as respiratory centres are insensitive to CO2. peripheral oedema and overweight from RHF.
what is cor pulmonale?
enlargement and failure of right side of the heart due to disease of lungs/pulmonary blood vessels - leads to oedema and raised JVP Rx = LTOT + loop diuretic
explain how cigarette smoke causes COPD
causes mucous gland hypertrophy in larger airways - increase in neutrophils, macrophages and lymphocytes in airway walls - release of inflammatory mediators - inflammatory cells attracted - structural changes - break down of connective tissue
what is alpha1-antitrypsin?
a protease inhibitor - inactivated by cigarette smoke
give 3 symptoms of COPD
cough, sputum, dyspnoea, wheeze
give 3 signs of COPD
tachypnoea, use of accessory muscles of respiration, barrel chest, hyperinflation, decreased cricosternal distance, resonant/hyperresonant percussion, quiet breath sounds, wheeze, cyanosis, cor pulmonale
give 3 complications of COPD
acute exacerbations ± infection (pneumococcal vaccine + yearly flu jab) cor pulmonale (RHF secondary to long standing lung disease/COPD) resp. failure *depression polycythaemia, pneumothorax, lung carcinoma
give 3 differential diagnoses of COPD
asthma, bronchiectasis, pulmonary embolism, congestive heart failure, pneumothorax
what would be the results of a lung function test in a COPD patient? other Ix?
reduced FEV1/FVC ratio (obstruction = FEV1/FVC <0.7) - NON-reversible, reduced PEFR. raised TLC. obstructive pattern. CXR = see other card for findings FBC - ?polycythaemia sputum culture if ?IECOPD ABG - hypoxia ± hypercapnia
what might you see on CXR in a COPD patient?
flattened diaphragm increased intercostal spaces hyperlucent lungs increased AP diameter
how would you conduct a steroid trial in COPD? what information would it give you?
patient given oral prednisolone for 2 wks. if FEV1 rises by >15% the COPD is steroid responsive - will benefit from long-term inhaled corticosteroids
how would you treat COPD?
ALMOST DEFS NEW GUIDELINES HERE - LOOK UP + LEARN don’t forget lifestyle/education etc ipratropium - short-acting antimuscarinic ± short-acting beta2 agonist -salbutamol, terbutamine ± inhaled tiotropium bromide - long-acting antimuscarinic ± long-acting beta2 agonist - salmeterol, formoterol Severe COPD: combination LABA + corticosteroids - Symbicort (budesonide + formoterol). OR - tiotropium + inhaled steroid + LABA
describe non-pharmacological treatment of COPD
pulmonary rehab programmes. smoking cessation. low BMI = diet advice ± supplements. long-term oxygen therapy (LTOT).
describe the features of the airway obstruction seen in asthma
reversible. bronchial muscle constriction. mucosal swelling/inflammation. increased mucous production.
