Asthma

Question 1

Asthma is defined as a reversible airway obstruction. How is ‘reversible’ obstruction of the always on spirometry defined?

Answer 1

> 12% increase in FEV1 and/or >200ml increase in FEV1 after SABA

Question 2

Excessive diurnal variation in serial peak flow measurements is indicative of asthma. How much variation would be considered ‘excessive’?

Answer 2

> 10%

Question 3

Describe the pharmacological management of stable asthma

Answer 3

SABA for all patients

Then as needed:

+ ICS, then
+LTRA, then
+LABA, then
increase dose of ICS

If on SABA, high dose ICS, LTRA and LABA and still uncontrolled, consider:

Biologics in eosinophilic asthma
Omalizumab in severe allergic asthma
Bronchial thermoplastic / tiotropine in non-type 2 asthma

Question 4

What defines a moderate asthma exacerbation?

Answer 4

Increase in symptoms
PEF >50-75% best or predicted
No features of severe exacerbation

Question 5

What defines a severe asthma exacerbation?

Answer 5

PEF 33-50% best or predicted
RR >25
HR >110
Inability to complete sentences

Question 6

What defines a life-threatening asthma exacerbation?

Answer 6

PEF <33%
SpO2 <92%
PaO2 <8kPa
PaCO2 is normal
Poor respiratory effort
Silent chest
Cyanosis
Arrythmias
Exhaustion or altered level of consciousness

Question 7

What defines a near-fatal asthma exacerbation?

Answer 7

Raised PaCO2 and/or need for mechanical ventilation

Question 8

How is a moderate asthma exacerbation treated?

Answer 8

Salbutamol nebulisers
Oral / IV corticosteroids
O2 and airway management
Monitoring and supportive care (IV fluids, correction of electrolyte abnormalities)

Question 9

How is a severe asthma exacerbation treated?

Answer 9

Treatment of moderate asthma exacerbation:
Salbutamol nebulisers
Oral / IV corticosteroids
O2 and airway management
Monitoring and supportive care (IV fluids, correction of electrolyte abnormalities)

Plus add:
Magnesium sulphate
Antibiotics

Question 10

How is a life-threatening asthma exacerbation treated?

Answer 10

ICU admission

Treatment of moderate asthma exacerbation:
Salbutamol nebulisers
Oral / IV corticosteroids
O2 and airway management
Monitoring and supportive care (IV fluids, correction of electrolyte abnormalities)

Plus add:
Magnesium sulphate
Antibiotics
Aminophylline
Consider invasive ventilation

Question 11

What are the potential complications of an acute asthma exacerbation?

Answer 11

Pneumonia
Respiratory failure
Pneumothorax
Effects of treatment e.g. ventilator associated lung injury
Death