Asthma (Raf)

Question 1

What is the definition of severe asthma?

Answer 1

Key point: Treatment needed: high dose ICS and second controller for previous year / oral steroids >50% last year -asthma either uncontrolled despite these or needing the above for prevention of loss of control
Supplemental points:
1) Asthma diagnosis confirmed by history and objective measures
2) Environmental factors, comorbidities, adherence and inhaler technique addressed before labelling as severe asthma

Question 2

Asthma control criteria as per CTS?

Answer 2

History: 
Daytime symptoms <4 days per week
No night time symptoms
SABA doses <4 doses per week 
No physical activity limitation 
Not missing any work or school 
Mild, infrequent exacerbations 
Objective testing: 
FEV1>=90% of personal best
Diurnal variation of PEF <10-15% 
Sputum eosinophils <2-3%

Question 3

Definition of uncontrolled asthma, as per ATS?

Answer 3

• Not meeting control criteria, as based on CTS criteria or standardized questionnaires
• Frequent severe exacerbations: 2 or more exacerbations needing oral steroids for >=3 days
• After bronchodilator withold, FEV1<80% of personal best or

Question 4

ABPA criteria for asthma?

Answer 4

• Based on ISHAM 2013:
• Total IgE>1000
• positive Aspergillus specific IgE or skin prick test
• 2 or 3 out of:
• Eosinophils > 500
• radiological features consistent with ABPA
• raised aspergillus IgG or precipitating antibody

Question 5

Normal values for FeNO in child (<12 years) and adult

Answer 5

Child: 20-34
Adult: 25-50

Question 6

What is considered significant difference in FeNO

Answer 6

For FeNO>50: 20% change is significant

For FeNO<50: 10 point change is signifciant

Question 7

What is the intepretation of an elevated FeNO?

Answer 7

• eosinophilic airway inflammation
• predsicts steroid responsiveness
• may suggest persistent allergen exposure
• can support the diagnosis of asthma, but there are also non-eoinophilic types of asthma
• can be used to monitor airway inflammation in asthma

Question 8

Patient with asthma, ongoing symptoms, but low FeNO?

Answer 8

Unlikely eosinophilic airway inflammation or persistent allergen exposure, unlikely to benefit from increased ICS dose, look for other causes of symptoms

Question 9

Asthma patient, no ongoing symptoms, low FeNO, manangement?

Answer 9

Consider weaning ICS and repeating FeNO in about 1 month

Question 10

Asthma patient, ongoing symptoms, high FeNO?

Answer 10

• eosinophilic airway inflammation or persistent allergen exposure
• inadequate ICS–non-adherence, poor technique or need an increase in dose
• risk for exacerbation

Question 11

Causes for low FeNO?

Answer 11

1) Adequately treated with steroids - no symptoms
2) Technical faults - constant expiratory flow is not maintained - will have symptoms
3) Smoking can cause lower FENO levels - can have symptoms
4) Non eosinophilic asthma(steroid resistant) - will have symptoms

Question 12

Why shouldn’t you use PEF in children

Answer 12

• PEFR should NOT be used to diagnose asthma since it is very effort dependent and only reflects obstruction in large central airways
• Numbers can be artificially high with tongue thrusts or spitting. Or they may be artificially low due to not enough effort or poor technique

Question 13

Onset of action for ipratropium and main side effect?

Answer 13

• Onset of action at 20 minutes, with peak at 60 minutes

- S/E: dry mouth

Question 14

Spiriva (tiotropium): drug category, receptor and duration of action?

Answer 14

• Anticholinergic
• Muscarinic receptor - M1, M2, M3 (it’s a muscarinic receptor antagonist)
• Duration: 24 hours (this is why there is a long withhold time of up to 48 hours prior to bronchodilator testing)
• Peak onset of action: 1-3 hours
• Typical dose: 2 puff of 1.25 micrograms, given once daily

Question 15

How is salmeterol different than formoterol?

Answer 15

• Salmeterol:
• slower onset of action (10-30 minutes) versus 5 minutes for formoterol
• shorter duration of action (9 hours) versus 12 hours
• partial agonist of the B2 adrenergic receptor so flatter dose response curve and less bronchoprotection against methacholine (recall that bronchoprotection and bronchodilation are similar, but slightly different effects of LABA)

Question 16

What is one respiratory condition that can get worse with bronchodilators?

Answer 16

Tracheomalacia

Question 17

Dose of prednisone for asthma exacerbation?

Answer 17

1-2 mg/kg/day x 5 days

Question 18

2 major phenotypes of preschool wheeze?

Answer 18

Viral episode wheeze (could also be called infection associated wheeze since wheezing happens with viral and bacterial infections): discrete episodes of wheezing with no symptoms in between. This is the subtype of preschool wheeze that is DIFFERENT than wheeze during school age

Multitrigger wheeze: symptoms during and in between episodes

Question 19

Mechanism of action for ICS?

Answer 19

ICS: reduces cytokines involved with the whole Th2 pathway of inflammation: IL5, other cytokines

Question 20

Limitations of asthma predictive scores, like API?

Answer 20

• Good for negative predictive value, but not for positive predictive value

Question 21

When predicting progression from preschool wheeze to asthma:

• sensitization to multiple allergens at an early age (multiple early atopy)
• severe and frequent episodic wheeze (Even if viral) ?

Answer 21

• These groups both have a high chance of future asthma.

- (Hard to predict progression for all other groups of patients)

Question 22

Predominant inflammatory cell in patient with suppurative lung disease (CF, PCD, bronchiectasis)?

Answer 22

Neutrophil

Question 23

Which chemokine attracts neutrophils?

Answer 23

IL1 (CXCL1), IL8 (CXCL8)

Question 24

Which chemokine attracts eosinophils to airway?

Answer 24

CCCL5, IL5

Question 25

What particles affect aerosol deposition?

Answer 25

``` Particle factors: - Size - Velocity - Viscosity and surface - Hygroscopic properties Patient factors: - age - inspiratory flow rate (breathing pattern) - nasal versus mouth breathing - anatomy of upper and lower airway - disease severity - cognitive ability/physical ability ```

Question 26

Ideal particle size for deposition in lower airways?

Answer 26

1-7 micrometers is considered respirable range >5 micrometers is likely to deposit in upper airway <3 micrometers for lower airway deposition