Adult Asthma Flashcards

1
Q

What is important in defining asthma?

A
  • Asthma is more of a concept than a definition

- Characterised by increased irritability (responsiveness), widespread narrowing of airways that changes in severity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why do airways narrow when they become inflamed?

A

They narrow as they become thicker and mucous and debris falls into the airway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is airway inflammation mediated by?

A

The immune system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the difference in diagnoses by sex?

A

Women are affected more than men

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Give some examples of how asthma impacts peoples lives?

A

Some asthmatics are totally and very limited by asthma. They struggle with:

  • Running
  • Stairs
  • DIY
  • Gardening
  • Sleeping
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the impact of asthma on the NHS?

A

It is mainly dealt with in primary care but there are 67,000 admissions to hospital.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the change in prevalence linked to?

A

Changes in environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the proven risk factors linked to asthma?

A
  • Genetic- atopy
  • Occupation
  • Smoking
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 2 genetic associations with asthma that linkage studies have identified?

A
  • Immune response genes: IL-4, IL-5, IgE

- Airway genes: ADAM33

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does genetics play a role in asthma?

A
  • Inherited tendency to IgE response to allergens.

- Often accompanied by eczema, hay fever or food allergy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What form of atopy is most influential?

A

Maternal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the most common cause of occupational asthma?

A

Bakers who are exposed to flour and microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are some examples of occupational asthma allergens?

A
  • Isocyanates: twin pack paints
  • Colophony: welding solder flux
  • Laboratory animals: rodent urinary products
  • Grains: wheat proteins, grain mites
  • Enzymes: subtilisin, amylase
  • Drugs: antibiotics, salbutamol
  • Crustaceans: prawns, crabs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does maternal smoking during pregnancy cause?

A
  • Decreased FEV1
  • Increased wheezy illness
  • Increased airway responsiveness
  • Increased asthma and severity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the grandmother effect?

A

If your grandmother smoked during pregnancy then you are 2.6X more likely to have asthma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the grandmother effect due to?

A

Mouse work suggests epigenetic modification of oocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What speculative risk factors are there?

A

-Obesity
-Diet
-Reduced exposure to microbes/microbial products
-Indoor pollution
-House dust mite
-Cat
Grass pollen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Speculative: What is an obese body mass index positively associated with?

A
  • Asthma
  • Wheezing
  • Airway hyperreactivity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Speculative: Supplements in asthma?

A

There are some associations between supplements and asthma but they have not effect in established disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Speculative: Exposure ot what microbial products is believed to reduce the likelihood of developing asthma?

A
  • Endotoxin
  • Glucans
  • Extracapsular polysaccharide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Speculative: Exposure to what chemical products is thought to increase the likelihood of asthma?

A
  • Volatile organic compounds
  • Formaldehyde
  • Fragrances
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Speculative: Who is at most risk of developing asthma related to indoor pollution?

A
  • Cleaners

- Mothers using sprays during pregnancy increases the chances of the child having asthma

23
Q

Speculative: Why is it thought that house dust mites increase the risk of asthma?

A
  • They thrive in warm, humid environments
  • They release 200X own weight in droppings
  • The droppings contain protease which is an allergen
24
Q

Speculative: Why does sensitisation to cats present a major problem?

A

There is constant exposure as cat hairs spread to peoples clothes and surfaces

25
Q

What can include localised airway obstruction?

A
  • Inspiratory stridor
  • Tumour
  • Foreign body
26
Q

What can be included in generalised airflow obstruction?

A
  • Asthma (reversible AFO)
  • COPD (irreversible AFO)
  • Bronchiectasis
  • Bronchiolitis
  • Cystic Fibrosis
27
Q

What common respiratory symptoms are often reported with asthma?

A
  • Wheeze
  • Short of breath (dyspnoea), severity
  • Chest tightness (pain)
  • Cough, paroxysmal, usually dry
  • Sputum (occasional)
28
Q

What are common triggers for asthma/

A
  • Exercise
  • Cold air
  • Smoke
  • Perfume
  • URTI’s
  • Pets
  • Trees
  • Grass pollen
  • Food
  • Aspirin
29
Q

What variations exist in asthma?

A
  • Daily variation (nocturnal/early morning)
  • Weekly variation ( in occupational, better at weekends and holidays)
  • Annual variation (environmental allergens)
30
Q

When taking a history, what is important to note?

A
  • PMH: childhood asthma, bronchitis, eczema, hayfever
  • Drugs: current inhalers, B-blockers, aspirin, NSAIDS, previous inhalers
  • FMH: atopic disease
  • PSH: smoking, pets, occupations past/present, psychological aspects
31
Q

What is usually unhelpful in the clinical setting?

A
  • Breathless on exertion
  • Hyperextended chest
  • Polyphonic wheezes
32
Q

What would suggest it wasn’t asthma?

A
  • Clubbing
  • Cervical lymphadenopathy
  • Stridor
  • Asymmetrical expansion
  • Dull percussion nota
  • Crepitations
33
Q

In essential investigations, what are you looking for?

A
  • Airflow obstruction

- Variability and/or reversibility of airflow obstruction

34
Q

What is spirometry used to determine?

A

If there is airway obstruction

35
Q

If there is airway obstruction, what is the next step?

A

Full pulmonary function testing

36
Q

What can be excluded after full pulmonary function testing?

A

COPD/ emphysema

37
Q

In pulmonary function testing what can lung volumes tell us?

A
  • Helium dilution test can indicate gas trapping:
  • Increased residual volume
  • Increased total lung capacity
38
Q

In pulmonary function testing what occurs during carbon monoxide gas transfer?

A

Transfer of CO to Hb across alveoli tells you how well the alveoli are working

39
Q

If there is airway obstruction, what should be done after pulmonary function testing?

A

Reversibility to bronchodilator

40
Q

Interpretation of reversibility to bronchodilator…

A
  • There should be significant reversibility
  • No bronchoconstriction= no reversibility
  • Severe bronchoconstriction= no reversibility
41
Q

Why is testing the reversibility to oral corticosteroids useful?

A

Separates COPD from asthma

42
Q

How should reversibility to oral corticosteroids be tested?

A
  • 0.6mg/kg of Prednisolone, 14 days
  • Peak flow chart and meter
  • Baseline and 2 week spirometry
43
Q

What does normal spirometry suggest?

A

Variability of airflow obstruction

44
Q

What might be seen in and asthmatics spirometry?

A
  • Morning/nocturnal dips
  • Decline over weeks/days
  • Variability >20%
45
Q

How is occupational asthma diagnosed?

A

-Serial peak flow readings
-2 hourly best 5 day minimum
2 pairs of exposed/ unexposed periods

46
Q

What specialist investigations can be carried out?

A
  • Airway responsiveness to methacholine/histamine

- Exhaled nitric oxide

47
Q

How is the level of exhaled nitric oxide useful?

A

Asthmatics usually have elevated levels of nitric oxide expired

48
Q

What other useful investigations are there?

A
  • Chest X-ray (hyperinflated/ hyperlucent)
  • Skin prick testing (atopic status)
  • Total and specific IgE (atopic status)
  • Full blood count (eosinophilia )
  • Useful but not diagnostic
49
Q

What is important to note when assessing severity of asthma?

A
  • Ability to speak
  • Heart rate
  • Respiratory rate
  • PEF
  • Oxygen saturation/ arterial blood gases
50
Q

What is suggestive of moderate asthma?

A
  • Abel to speak in complete sentences
  • HR<110
  • RR<25
  • PEF 50-75% predicted or best
  • SaO2 > 92%
  • PaO2>8kPa
51
Q

What is suggestive of sever asthma?

A
  • Unable to speak in complete sentences
  • HR>110
  • RR>25
  • PEF 33-50% predicted or best
  • SaO2 >92%
  • PaO2>8kPa
52
Q

What is suggestive of life threatening asthma?

A
  • Grunting
  • Impaired consciousness, confusion, exhaustion
  • HR>130 or bradycardic
  • Hypoventilating
  • PEF<33% predicted or best
  • Cyanosis
  • SaO2<92%
  • PaO2<8kPa
  • PaCO2 normal
53
Q

What is suggestive of near fatal asthma?

A

Raised PaCO2