1. Asthma and COPD Roger Deering + Phil Thirkell

2. Asthma - Definition A chronic inflammatory disorder of the airways… Symptoms usually associated with variable airflow obstruction and an increase in airway response to a variety of stimuli. Obstruction is often reversible.

3. COPD - Definition Irreversible aspect of – Emphysema – Chronic bronchitis – Asthma Pulmonary component = airflow limitation (not fully reversible and usually progressive)

4. Pathology – Asthma Triggers Allergens Air pollution Infection Exercise Smoking Pets

5. Pathology – COPD Large Airway Mucus hypersecretion. Neutrophils in sputum. Squamous metaplasia of epithelium – no basement membrane thickening. ↑ macrophages. ↑ CD8 lymphocytes Mucus gland hyperplasia Goblet cell hyperplasia Little increase in airway smooth muscle Small Airway Inflammatory exudate in lumen. Disrupted alveolar attachments. Thickened wall with inflammatory cells (macrophages, CD8s and fibroblasts). Peribronchial fibrosis. Lymphoid follicle – in severe COPD Lung Parenchyma Alveolar wall destruction. Loss of elasticity. Destruction of pulmonary capillary bed. ↑ inflammatory cells, macrophages, CD8 lymphocytes Result = Airflow limitation

6. Causes of airflow limitation – in simpler terms Fibrosis = narrowing of lumen. Alveolar destruction = loss of elastic recoil. Destruction of surrounding alveolar support = loss of small airway patency. Irreversible Accumulation of inflammatory cells, mucus and exudate. Smooth muscle contraction. Dynamic hyperinflation. Reversible

7. Pathology – COPD Risk Factors Host Factors Genetic (a1- antritrypsin deficiency) Hyper- responsive ness Exposure Tobacco Occupational dusts/chemic als Poor socio- economic status (damp etc.)

8. Cells involved

9. Let’s get clinical! Asthma Signs/symptoms Wheeze Cough Chest tightness Dyspnoea DIB Things to look for on Hx Date of onset Other atopic disease Family Hx Smoking/Occupation/Pets Provocation 3 things to ask Day time control Amount of relieving meds required Night time control COPD Signs/Symptoms Cough Sputum Dyspnoea Things to look for on Hx SMOKING Work Hx Family Hx (α1-antitrypsin)

11. Peak Flow – mainly asthma monitoring at GP and home – Stand up – Breathe out – Maximum breath in – Seal lips around cardboard tube – Blow out as hard and fast as possible litres/minute Best of 3 readings Depends on technique – practice required Peak flow diary

12. Spirometry – diagnosis/differentiation of asthma/COPD and monitoring Forced vital capacity - FVC Forced expiratory volume in 1 second – FEV 1 GP surgery - nurses trained for spirometry Predicted FEV 1 and FVC - Height, Weight, Age, Gender <80% of predicted for FVC or FEV 1 is abnormal FEV 1 /FVC ratio differentiates asthma and COPD – <0.7 = obstructive lung disease – >0.7 = restrictive lung disease Contraindications: recent surgery, ENT disorders, recent pneumothorax, haemoptysis, communicable disease

13. Reversibility/Bronchoprovocation Reversibility – Give salbutamol and retest FEV 1. If increased after salbutamol it’s more likely to be asthma, not COPD Bronchoprovocation – Checking for hypersensitivity in asthma – Nebulised histamine or methacholine causes airway constriction, seen in asthma

14. Obstructive vs. Restrictive Obstructive – Narrowed airways, reduces the amount of air that can pass through at any time – Reduces FEV 1 e.g. COPD and Asthma Restrictive – Lungs can’t expand as much, so FVC is reduced e.g. Interstitial lung diseases, sarcoidosis, obesity

15. obstructive restrictive

16. Management of Asthma and COPD Patient education – symptom recognition – allergen avoidance – exercise – diet – smoking cessation

17. Asthma

18. COPD Stop smoking β 2 -agonists Anti-cholinergics Steroids Methylxanthines (theophylline) Long term oxygen therapy (LTOT) Infection prevention – flu jab Rescue packs – steroids + antibiotics

19. β 2 -agonists – salbutamol, salmeterol Reliever inhalers Relax smooth muscles in airways Activates G-protein coupled receptors Tolerance develops SE: tremor, headache, tachycardia

20. Anti-Cholinergics – ipratropium, tiotropium (inhalers) Blocks muscarinic receptors (M3) of the parasympathetic NS Reduces contraction to open airways SE: dry mouth, constipation, urinary retention

21. Methylxanthines (theophyllines/aminophylline) – ↑ PDE – Need close monitoring – SE: insomnia, nausea, vomiting Leukotriene Antagonists (montelukast) – Block inflammatory phase – Tablet, used as a preventer Steroids (beclometasone, prednisolone) – Preventers – Reduce inflammation – Loads of side effects Inhaled Oral

22. Mast Cell Stabilisers (sodium cromoglycate) – Reduces histamine release from mast cells Monoclonal antibodies (omalizumab) – Binds IgE to stop histamine release from mast cells – Expensive

23. Asthma Attack Management O – high flow Oxygen S – salbutamol (nebulised) H – hydrocortisone (IV) I – ipratropium (IV) T – theophylline (IV) + intubation