Asthma

Question 1

T or F:

Asthma is an acute, progressive condition.

Answer 1

F, it has acute episodes (asthma attacks) but the condition is chronic and progressive.

Question 2

Describe asthma:

Answer 2

• Inflm/bronchospasm of the airways
• Episodic obstruction
• Reversible episodes d/t various stimuli
• Hyper-responsive airways
• Muscles hypertrophy

Question 3

What happens when airways become hyper-responsive?

Answer 3

• Episodes become more frequent and severe

- New triggers develop

Question 4

What is the atopic form of asthma?

Answer 4

A genetically induced allergic reaction to stimuli

- Inflm in the airways, bronchoconstriction

Question 5

What is the non-atopic form of asthma?

Answer 5

A normal response to stimuli
- The normal bronchoconstriction that may result from
breathing in cold air

Question 6

What is the Et of asthma?

3

Answer 6

• Complex trait
  
  • Environmental and genetic
• Hypersensitivity to triggers:
  
  • Allergens
  • Airway irritants
  • Strong odors
• T cell differentiation toward T2H

Question 7

When do type 1 helper T cells occur? When do type 2 occur?

Answer 7

Type 1 - When in contact with microbes (happens pree much all the time)
Type 2 - When in contact with an allergen or helminth parasites (flat worm)

Question 8

Explain what happens during the early stage of an asthma attack:

Answer 8

• Type 1 hypersensitivity reaction
• Must have prior sensitization of mast cells
  
  • IgE Abs are already bound to the mast cells
• Intercellular junctions open -> allergens enter submucosa
• Increased permeability and mucus hypersecretion ->
  edema of the airway, serous exudate
• Bronchospasm
• Visible dyspnea, audible wheezes

Question 9

When a person without asthma breathes in an irritant, what happens?

Answer 9

A neuro response to constrict their airway kicks in. This is a protective measure to prevent too much irritant entering the lungs.

Question 10

What happens during the delayed-phase response in asthma?

Answer 10

• Happens in ~50% of asthma cases
• Delayed by 4-8 hours post exposure
• Self sustaining cycle of exacerbation
  
  • Can last from days to weeks
• Large influx of inflm cells due to chemotaxis
  
  • Cause epithelial damage
  • Decreased mucociliary Fx
• Airways become hyper-responsive

Question 11

What homeostatic responses are responsible for balancing the patency of airways? What is one proposed theory about these which relates to asthma?

Answer 11

cAMP mediates the binding of:
- Beta adrenergic receptors - bronchodilation
- Alpha adrenergic receptors - bronchoconstriction
- One theory suggests that in people with asthma there
is a lack of beta receptor stimulation

Question 12

What are the mnfts of asthma?

6

Answer 12

• Dyspnea
• Wheezing, coughing
• Bronchospasm (not seen directly)
• Increased respiratory effort
  
  • Pursed lip breathing
  • Nostrils flaring
• Barrel chest
• Abn ABGs

Question 13

What is used to Dx asthma?

Answer 13

• Pulmonary Fx tests
• Inhalation challenge tests
  
  • Expose patient to potential allergens and monitor
    for hypersensitivity reaction

Question 14

What has changed recently about the focus of care for patients with asthma?

Answer 14

Went from “treat the episode” to “prevent the episode from ever occurring”

Question 15

There are 4 steps in which different drugs are used to treat asthma. Explain each step:

Answer 15

Step 1: Short acting inhaled bronchodilator PRN
Step 2: Add inhaled steroids
Step 3: Add long acting bronchodilator to steroid
Step 4: a) Short course of PO steroid
b) Add a 3rd drug, leukotriene receptor
antagonist or theophylline
- In a normal response, this would mediate
inflm and further the allergic reaction, so
the antagonist will help prevent those
physiological responses