Asthma

Question 1

What is asthma?

Answer 1

chronic inflammatory disorder and bronchoconstriction usually triggered by allergies such as dust animals and food

Question 2

what are the symptoms of asthma

Answer 2

wheezing, SOB, cough worse at night, exacerbations during seasonal changes and family history higher chance of asthma

Question 3

name three lung function tests

Answer 3

spirometry
peak expiratory flow
fractional exhaled nitric oxide

Question 4

describe spirometry

Answer 4

FEV1 - amount of air exhaled in 1 sec
FVC - max amount of air can exhale
FEV1/FVC - total air can exhale in 1 sec compared to max capacity
value less than 80% for FEV1 and FVC - compromise
value less than 0.7 for FEV1/FVC - compromise

Question 5

describe Peak expiratory flow

Answer 5

measures how fast person can exhale

Question 6

describe fractional exhaled nitric oxide

Answer 6

tell difference between asthma and other inflammatory disease

Question 7

what are the two types of asthma

Answer 7

extrinsic and intrinsic

Question 8

describe extrinsic

Answer 8

most common
onset in children
usually have allergies and history in family 
\+ skin test
mild 
treatable

Question 9

describe intrinsic

Answer 9

less common
not seen in children often
not caused by allergies
severe

Question 10

describe bronchoconstriction in asthma

Answer 10

cause by allergen

FEV1 is reduced within 15 mins but returns to baseline with hour with SABA or alone

Question 11

describe the early asthmatic reaction

Answer 11

bronchoconstriction caused by allergen
allergen will bind to IgE in cell membrane which activates mast cells
mast cells will release mediators like histamine, leukotriene and prostaglandins
cysteinly leukotrienes are most potent brochoconstrictors
other inflammatory cells are activated - eosinophils

Question 12

describe pathophysiology of asthma

Answer 12

1 allergen/antigen binds to antigen presenting cell
2 TH2 then act on TH1 and B lymphocytes and eosinophils
3 B lymphocytes release IgE that activates mast cells
4 mast cells will release inflammatory mediators - histamine and leukotrienes
5 leads to increase contraction and increase mucus production which increases airway obstruction

Question 13

what are mast cells

Answer 13

cause inflammation of the airways in asthmatic pt

Question 14

what is the treatment guideline?

Answer 14

1. relief inhaler - SABA - salbutamol
2. add preventer - inhaled corticosteroids - beclomethsone
3. add LABA - salmeterol
4. add oral corticosteroids - prednisone

Question 15

describe beta 2 agonists

Answer 15

are bronchocodilators

• reduce release from mast cells - inhibit histamine release
• may cause tremors
• inhibit cholinergic neurotransmissions - stop Ach leads to dilation

Question 16

describe SABA

Answer 16

• salbutamol and fenoterol
• used for acute bronchospasm
• rapid onset

Question 17

describe LABA

Answer 17

• salmeterol
• not used in acute attach
• always used with anti inflammatory therapy
• used twice daily rather than when needed with SABA

Question 18

describe anticholinergics

Answer 18

• bronchodilator, inhibits acetylcholine and mucus
• less effective than beta agonist
• ipratropium and tiotropium

Question 19

describe inhaled corticosteroids

Answer 19

• anti inflammatory effect and dose not case bronchodilation
• reduces symptoms and protects against triggers of asthma
• repress and inactivates genes involved in inflammation
• low dose will inhibit HAT - repress inflammatory genes
• higher dose have more side effects