Asthma and Bronchodilators

Question 1

What is asthma?

Answer 1

Variable narrowing of the airways

Question 2

What are the 2 features of pathophysiology of asthma?

Answer 2

• Smooth muscle abnormalities: hyperresponsiveness and hypertrophy
• Airway inflammation

Question 3

How to diagnose asthma?

Answer 3

Spirometry
Peak expiratory flow

Question 4

What does asthma eventually lead to?

Answer 4

Airflow obstruction

Question 5

What factors can lead to variable airflow obstruction? (4 points)

Answer 5

• Triggers such as exercise and irritants
• Spontaneous diurnal variation
• Response to treatment
• Exposure to allergens

Question 6

In people with asthma, lung function can be normal. True or false?

Answer 6

True

Question 7

What are symptoms of asthma?

Answer 7

Wheeze, breathlessness, chest tightness
Variable symptoms usually worse at night or early morning; worse with exercise, irritant exposures, cold air etc
Cough, sputum

Question 8

What are some non-pharmacological treatment options for asthma?

Answer 8

Stop smoking
Avoid triggers
Weight loss

Question 9

What are the 2 types of pharmacological asthma treatment (inhalers)?

Answer 9

Bronchodilators (relievers)
Anti-inflammatory agents (preventers)

Question 10

What drugs are classed under the bronchodilators “relievers”? (4 points)

Answer 10

Beta adrenergic agonists
Anticholinergics
Theophylline
Magnesium

Question 11

What drugs are classed under anti-inflammatory agents “preventers”? (3 points)

Answer 11

Corticosteroids
Leukotriene antagonists
Anti IgE antibodies

Question 12

What nerve supplies the parasympathetic nervous system of the airway smooth muscle (constriction)?

Answer 12

Vagus

Question 13

What 1) receptor and 2) hormone stimulate the sympathetic nervous system of the airway smooth muscle (relaxation and dilatation)?

Answer 13

1) β2 adrenergic receptor
2) Circulating adrenergic hormones eg adrenaline

Question 14

What 1) molecule and 2) ionic changes contribute to the constriction and dilatation of the airway smooth muscles?

Answer 14

1) cAMP
2) Changes in intracellular calcium

Question 15

How do anticholinergics work to dilate the bronchus/airway?

Answer 15

They block off the vagus nerve, allowing the β2 receptor to take over

Question 16

What can act on β2 receptors and lead to an increase in cAMP causing bronchodilation?

Answer 16

β2 agonists

Question 17

How does theophylline work as a bronchodilator?

Answer 17

Blocks the break down of cAMP therefore causing an increase of intracellular calcium which increases smooth muscle relaxation

Question 18

How does magnesium work as a bronchodilator, usually for life-threatening asthma cases?

Answer 18

Displaces intracellular calcium causing potent and rapid airway smooth muscle dilation

Question 19

What are the different types of beta adrenergic agonists (asthma treatment) and examples?

Answer 19

Short acting ‘relievers’ eg Salbutamol/ventolin, Terbutaline (duration 2-4 hours)
Long acting eg Salmeterol, Formoterol (duration 12 hours)
Oral
Intravenous

Question 20

What colour is the salbutamol/ventolin inhaler?

Answer 20

Blue

Question 21

What is an example of a powder inhaler?

Answer 21

Terbutaline

Question 22

What are the effects of beta adrenergic agonists? (5 points)

Answer 22

• Bronchodilation
• Tachycardia
• Hypokalaemia
• Hyperglycaemia
• Tachyphylaxis (if a drug is used repeatedly, receptors are worn out and drug no longer has an effect)

Question 23

What are examples of anticholinergics and how do they treat asthma?

Answer 23

Ipratropium and Tiotropium
Inhibit vagal tone

Question 24

What are the side effects of anticholinergics? (3 points)

Answer 24

• Dry mouth
• Glaucoma
• Urinary retention

Question 25

Theophylline is a ________ derivative. It can be prepared __________ and intravenously. It has a _______ therapeutic window. The drug that it interacts with and is dangerous in overdose is _____________. Possible side effects include tachyarrthythmias, ventricular fibrillation and _____________.

Answer 25

Caffeine. Orally. Narrow. Erythromycin. Convulsions.

Question 26

How is magnesium usually administered?

Answer 26

Intravenously

Question 27

What are the three drug classes of anti-inflammatory agents "preventers" of asthma treatment?

Answer 27

Corticosteroids Leukotriene antagonists Anti-IgE antibodies

Question 28

What are the different types and examples of corticosteroids "preventers" asthma treatment?

Answer 28

Inhaled: beclomethasone, budesonide, fluticasone Oral: prednisolone Intravenous

Question 29

What are the possible side effects of corticosteroids "preventers"?

Answer 29

Inhaled: oropharyngeal candidiasis, dysphonia, bruising, cataracts Oral: osteoporosis, skin thinning, hypertension, adrenal suppression, diabetes

Question 30

Leukotriene antagonists are _____ that are not very effective so not many people take it.

Answer 30

Tablets

Question 31

What do leukotriene antagonists and anti-IgE antibodies target when treating asthma?

Answer 31

Allergens (eg cat, house dust mite) + Specific IgE antibodies -> release of inflammatory mediators from mast and other cells

Question 32

In combination inhalers, what are the combined drugs?

Answer 32

Inhaled corticosteroid + long acting beta agonist

Question 33

What are some examples of combination inhalers?

Answer 33

Seretide: salmeterol + fluticasone Symbicort: formoterol + budesonide

Question 34

What are the different devices used during asthma treatment that help get the drug into the patient's lungs through the small airways?

Answer 34

* Pressurised metered-dose inhalers * Spacer devices * Self-actuating devices * Dry powder inhalers * Nebulisers

Question 35

Pressurised metered-dose inhalers are convenient but they require ________ and high ________ _______ as they are breath actuated devices. They have ____________ ____________.

Answer 35

Coordination. Inspiratory flow. Oropharyngeal deposition

Question 36

Spacer devices (decrease/increase) the need for coordination. They (decrease/increase) oropharyngeal deposition and (decrease/increase) airway deposition.

Answer 36

Decrease Decrease Increase

Question 37

Dry powder devices usually require (higher/lower) inspiratory flow rate. (More/less) coordination is needed. They do not contain propellant.

Answer 37

Lower. Less.

Question 38

Nebulisers can administer very (high/low) doses but they are very inefficient. They may delay hospital admission.

Answer 38

High

Question 39

How to manage acute severe asthma?

Answer 39

1. Assess the severity 2. Summon help 3. Support the patient to sit up 4. Give high dose of bronchodilator (use nebuliser if avaible; improvise spacer device; salbutamol inhaler) 5. Give corticosteroids/oxygen

Question 40

Assessing asthma severity * Moderate asthma exacerbation: increasing symptoms, PEF >__ - __% best or predicted, no features of acute severe asthma * Acute severe asthma: any one of PEF __ - __% best or predicted, respiratory rate >=25/min, heart rate >=110/min, inability to complete sentences in one breath * Life threatening asthma: any one of PEF < __% best or predicted, SpO2 < 92%, PaO2 < 8kPa, 'normal' PaCO2 4.6-6.0kPa, clincal signs of altered conscious level, exhaustion, arrhythmia, hypotension, cyanosis, silent chest, and poor respiratory effort. * Near-fatal asthma: raised PaCO2 and/or requiring mechanical ventilation with raised inflation pressures

Answer 40

>50-75% 33-50% <33%