Asthma Flashcards Preview

OSCE Conditions > Asthma > Flashcards

Flashcards in Asthma Deck (14):
1

Signs of asthma

Polyphonic wheeze
Hyperresonant on percussion
Barrel chest

2

Pathophysiology of asthma

A chronic inflammatory disorder of the airways:
- Immediate phase: (type 1 hypersensitivity) allergen causes interaction of IgE with mast cells, histamine released, causes bronchoconstriction
- Late phase: (type IV hypersensitivity) inflammatory cells release cytokines leading to an immune response, causes bronchospasm, thickening of BM, odema and mucus production

Airway narrowing leads to reduced ventilation of alveoli, causes V/Q mismatch and reduced gas exchange

3

Questions in asthma history

Family history
Allergies
Smoking
Dry cough? Worse at night?
Triggers?

4

Investigations of asthma

Low PEFR
Low FEV1/FVC ratio - reversible with salbutamol
Skin prick tests for allergens

5

Describe the steps in the management of asthma

1. Inhaled short acting B2-agonist when required eg. Salbutamol
2. Addition of inhaled steroid eg. Budesonide
3. Addition of long acting B2-agonist (LABA) eg. Formoterol, salmeterol
4. Increase inhaled steroids/ add 4th drug (methylxanthines eg. Theophylline, muscarinic antagonist eg. Ipatropium bromide)
5. Addition of an oral steroid/ anti-IgE therapy

6

Describe the principles of treatment in asthma

Aims to minimise symptoms
Minimise need for reliever medication
Reduced exacerbation frequency
Reduce limitation on physical activity
Give normal lung function

7

Mechanism of action of B2-agonists

Bind to B2 receptors, increase cAMP levels, reduced Calcium, reduced activation of myosin light chain kinase, prevents muscle contraction.
Causes bronchodilation

8

ADRs and contraindications of B2 agonists

ADRs: tachycardia, palpitations, tremors
Contraindications: cardiac ischaemia, arrhythmias

9

Mechanism of action of corticosteroids in asthma

Anti inflammatory effect.
Suppress gene transcription in inflammatory cells and repress inflammatory responses -> apoptosis of inflammatory cells.

10

ADRs of corticosteroids

Croaky voice, sore throat, thrush

11

Give an example of a combined inhaler and what it contains

Symbicort
Mixture of budenoside and formoterol

12

How would you treat acute severe asthma

Give oxygen
Nebulised salbutamol
Oral prednisolone
- if not responding ass nebulised ipratropium bromide

13

Symptoms of asthma

Breathlessness
Chest tightness
Cough - dry, worse at night
Brought on by triggers

14

Asthma differential diagnosis

Alpha-1-antitrypsin deficiency
COPD
Bronchiectasis
Upper resp tract infection
Foreign body in airway