Clinical features of asthma in adulthood and children

Question 1

_Describe the defining features and

Answer 1

• “gasp for breath”
• Complex disease- history of respiratory symptoms such as:
  o Expiratory Wheezing -KEY. WORD.
  o Shortness of breath
  o Coughing
  o Chest tightness
  o ^ all together with difficulty in expiration.
• Define features include an increased responsiveness of the trachea and bronchi to various stimuli which results in airflow obstruction. It is manifested by a widespread narrowing of airways that changes in severity either spontaneously or a result of therapy.

Question 2

epidemiology of asthma,

Answer 2

The NHS spends around 1 billion a year treating and caring for people with asthma. One in 11 children has asthma and it is the most common long-term medical condition. … The UK has among the highest prevalence rates of asthma symptoms in children worldwide

Question 3

Describe the pathophysiology of asthma.

Answer 3

• Very complex
• Inflammation of the airways mediated by the immune system – causing:
   Widespread narrowing of airways
  • Changes in severity either spontaneously or in response to stimuli.
   Increased airway reactivity

Question 4

Describe proven and putative aetiological factors.

Answer 4

• Hereditary
  o Especially first degree family member has asthma or another atopic disease.
  o Maternal atopy most influential most influential (3* more than father)
  o Atopy is the body’s predisposition to develop an antibody called immunoglobulin (IgE) in response to exposure to environmental allergens and is an inheritable trait
  o Associated with asthma

-	Smoking:
o	Maternal smoking during pregnancy:
	Decrease in FEV1
	Increase in Wheezy illness
	Increase in airway responsiveness
	Increase in asthma
	Reduction in lung function
o	“Grandmother effect”

-	Occupation:
o	Underestimated (10-15% of adult onset asthma)
o	Interactions with smoking and atopy:
	Isocyanates (paints)
	Lab animals (rodent urinary proteins)
	Grains 
	Enzymes
	Drugs
	Shell fish

Question 5

Triggers/provokes asthma

Answer 5

Different for each individual:

• Pets
• Tree or grass pollen
• Cigarette smoke
• Exercise
• Drugs (aspirin/NSAIDS)

Question 6

Different for each individual:

• Pets
• Tree or grass pollen
• Cigarette smoke
• Exercise
• Drugs (aspirin/NSAIDS)

Answer 6

It is mostly about the history.
Clinical Test:
o Test for airway Obstruction
o Spirometry and bronchodilator reversibility
o FEV1/FVC ratio
o If they have normal spirometry, do not exclude asthma
o Reversibility to bronchodilator, corticosteroids
o Variable airflow obstruction: peak flow charts

Question 7

If obstructed picture: Full pulmonary function testing. what does this exclude?

Answer 7

COPD/emphysema

Question 8

Carbon monoxide gas transfer (transfer of CO to Hb across alveoli)

Answer 8

Gas transfer very important is differentiating between COPD and asthma.

good at identifying COPD

Question 9

• _Contrast the management of asthma with strategies for management of COPD.

Answer 9

Initial treatments of COPD include bronchodilators, while initial treatments for asthma include inhaled corticosteroids

Question 10

Oher useful investigations:

Answer 10

• Chest X-Ray but it tends to look normal
  Hyperinflated, hyperlucent
  (no effusion, collapse, opacities, interstitial changes)
• Skin prick testing (atopic status)
• Total and specific IgE (atopic status)
• Full blood count
  Eosinophilia (atopy)

Question 11

Define the specific features to be included in the clinical history of asthma.

Answer 11

• Compatible Symptoms: wheezing, chest tightness, breathlessness, coughing. Occasionally sputum (BUT more common in COPD)
• Past medical history:
  o Childhood asthma, bronchitis or wheeze in infancy
  o Eczema
  o Hayfever
• Drugs:
  o Have they been on any treatment for asthma and what has its effect been?
  o Current inhalers (check technique!), compliance
  o -blockers, aspirin, NSAIDS
  o Effects of previous drugs/inhalers
• Family history:
  o Asthma and other atopic disease

-	Social history:
o	Tobacco, recreational drugs, vaping
o	Pets
o	Occupation (past and present)
o	Psychological aspects- stress can make asthma worse

Question 12

Probably not asthma if:

Answer 12

• Finger clubbing
• Stridor- inspiratory wheeze (large airways)
• Asymmetrical expansion, dull percussion note (collapse/effusion)
• Crepitations

Question 13

What else could it be if its not asthma?

Answer 13

• Generalised airflow obstruction
  o COPD (irreversible AFO)
  o Bronchiectasis
  o Cystic Fibrosis
• Localised airway obstruction: inspiratory stridor= large airways
  o Tumour
  o Foreign body
• Cardiac

Question 14

• _list the factors to assess the severity of acute, severe asthma.

Answer 14

Assess it via Objective parameters>subjective

• Ability to speak
• Heart rate
• Respiratory rate
• PEF
• Oxygen saturation / Arterial blood gases

Question 15

• _Explain how to assess the severity of acute, severe asthma.

moderate

Answer 15

Moderate:
Essentially increasing symptoms, 
-	Able to speak, complete sentences
-	HR < 110
-	RR < 25
-	PEF 50 - 75% predicted or best
-	SaO2 ≥ 92% (no need for ABG)
-	PaO2 ≥ 8kPa

Question 16

• _Explain how to assess the severity of acute, severe asthma.

severe

Answer 16

Severe:
Any one of 
-	Inability to complete sentences in one breath
-	HR ≥110
-	RR ≥25
-	PEF  33 - 50% predicted or best
-	SaO2 ≥ 92% 
-	PaO2 ≥ 8kPa

Question 17

• _Explain how to assess the severity of acute, severe asthma.

life threatening

Answer 17

Life threatening:
Any one of
-	Grunting
-	Impaired consciousness, confusion, exhaustion
-	Bradycardia/ arrhythmia/ hypotension
-	PEF < 33% predicted or best
-	Cyanosis
-	Silent chest
-	Poor respiratory effort
-	SaO2 < 92% (definitely needs blood gas!)
-	PaO2 < 8kPa
-	PaCO2 normal (4.6 - 6.0kPa)

Question 18

• _Explain how to assess the severity of acute, severe asthma.

near fatal

Answer 18

Near Fatal:

• Raised PaCO2
• Need for mechanical ventilation

Question 19

asthma children lecture:

Near Fatal:

• Raised PaCO2
• Need for mechanical ventilation

Answer 19

• Genes
• Host response to environment
• Infection is important, especially in paediatrics
• Physiology is abnormal before symptoms

Question 20

There are many inconsistencies:

Answer 20

• “Transient” vs persistent
• VIW versus asthma/MTW
• Different severities
• Different age at onset
• Heterogeneity in response- not just a single asthma gene, there are 10 variants with the two most common ones being ADAM33 and ORMDL3
• Different triggers

Question 21

Allergy usually does not cause asthma.

Answer 21

• Primary epithelial abnormality (of the skin/airway/gut) results:
  o Excema/asthma
  o Allergy -> allergy then fuels eczema/asthma

Question 22

When is it asthma in children?

Answer 22

• Always at the doctor for a wheezy cough

- Shortness of breath at rest

Question 23

When is it not asthma?

Answer 23

• Under 18 months, most likely infection

- Over 5 years, highly likely asthma

Question 24

Asthma treatment

Answer 24

• Inhaled corticosteroids for 2 months- if its not asthma then it has no bad effect anyway.
• Remember “false positive responses”- holiday

Question 25

Asthma vs VIW (Viral induced wheeze)

Answer 25

The difference between asthma and viral-induced wheeze is that children with asthma will wheeze at times other than when they have a cold – often with exercise or when they are exposed to particular ‘triggers’ like house dust mites or pets.
VIW is usually during a cold.

Most children with viral-induced wheeze will stop wheezing as they get older and will not develop asthma.