Respiratory Medicine - Asthma

Question 1

What is asthma?

Answer 1

1. Asthma may be defined as a chronic inflammatory disorder of the airways secondary to hypersensitivity. 2. The symptoms are variable and recurring and manifest as reversible bronchospam resulting in airway obstruction.

Question 2

Risk factors and aetiology?

Answer 2

A number of factors can increase the risk of a person developing asthma: 1. Personal or family history of atopy 2. Antenatal factors: maternal smoking, viral infection during pregnancy (especially RSV) 3. Low birth weight 4. Not being breastfed 5. Maternal smoking around child 6. Exposure to high concentrations of allergens (e.g. house dust mite) 7. Air pollution 8. ‘Hygiene hypothesis’: studies show an increased risk of asthma and other allergic conditions in developed countries. Reduced exposure to infectious agents in childhood prevents normal development of the immune system resulting in a Th2 predominant response

Question 3

Patients with asthma also suffer from?

Answer 3

IgE-mediated atopic conditions such as: 1. atopic dermatitis (eczema) 2. allergic rhinitis (hay fever)

Question 4

Symptoms and signs?

Answer 4

Symptoms: 1. cough: often worse at night 2. dyspnoea 3. ‘wheeze’, ‘chest tightness’ Signs: 1. expiratory wheeze on auscultation 2. reduced peak expiratory flow rate (PEFR)

Question 5

Investigations?

Answer 5

1. FEV1: forced expiratory volume - volume that has been exhaled at the end of the first second of forced expiration 2. FVC: forced vital capacity - volume that has been exhaled after a maximal expiration following a full inspiration

Question 6

Typical results in asthma?

Answer 6

1. FEV1 - significantly reduced 2. FVC - normal FEV1% (FEV1/FVC) < 70%

Question 7

Drugs used in Asthma management? Salbutamol

Answer 7

The first-line drug to be used in the management of asthma
Typically used if the patient develops symptoms
When discussing with patients often termed ‘the reliever’
They work by relaxing the smooth muscle of airways
Side-effects include tremor

Question 8

Drugs used in Asthma management? Beclometasone dipropionate, Fluticasone propionate

Answer 8

Beclometasone dipropionate, Fluticasone propionate

1. Used in patients whose asthma is not controlled by SABA alone
2. Taken everyday, regardless of whether the patient has symptoms
3. When discussing with patients often termed ‘the preventer’
4. Side effects include oral candidiasis and stunted growth in children

Question 9

Drugs used in Asthma management? Salmeterol

Answer 9

1. LABAs, as their name suggests, are longer acting versions of SABAs
2. They are taken, like ICS, everyday, regardless of whether a patient has symptoms

Question 10

Drugs used in Asthma management? Monteleukast

Answer 10

Leukotriene receptor antagonists

• Oral medication

Question 11

Management of asthma has changed slightly following the 2016 British Thoracic Society guidelines. The main take home points are that all patients are started on a inhaled corticosteroid at the time of diagnosis, in addition to a short-acting beta-agonist:

Answer 11