Asthma

Question 1

what is asthma

Answer 1

reversible episodes of airway obstruction d/t:

• muscle hyperactivity (in airways–contraciton/relaxation in excess)
• Inflm (exudate & swelling compromising airway)

Question 2

what is atopy

Answer 2

genetically induced hypersensitivty some predisposition there

Question 3

asthma as ______ and ______ forms

Answer 3

extrinsic(atopic) & Intrinsic (non-atopic) factors

Question 4

what is the etiology(cause of asthma)?

Answer 4

• complex
• genetic & environmental factors
• hypersensitivity to stimuli (such as allergens, strong odours, a/w irritants, exercise)
• T cell differnetaiton toward T2H (T1 helper cells propageted in defense to microbes, bacteria, virus, cytokine. T2 helper cells in defense of antigens)

Question 5

patho of asthma

Answer 5

• stimulus
• hypersenstivity
• 2 phased response

Question 6

there are _____ and _____ triggers of asthma

Answer 6

non atopic tiggers: infection, drugs, cold air

atopic triggers: allergens

Question 7

when do the early and late phases of asthma happen

Answer 7

early phase: begins right away only lasts about an hour(not an absolute number could differ)
late phase: peaks a 6 hrs, can last hours or days

Question 8

what are the manifestations of asthma?

Answer 8

• wheezing (drawing & expelling air forcefully through narrowed airways)
• dyspnea
• increased resp effort (pursed lip breathing) (nasal flaring)
• alt resp statues & ABGS (changes in abgs)

Question 9

diagnosing asthma

Answer 9

• hx, px
• pulm function tests (spirometery)
• labs
• inhalation challenge tests (testing for hyperresponsivness to inhlaed allergens)

Question 10

treatment of asthma

Answer 10

• control with decreased meds (chronic control use as little meds as possible)
• preventative measures: no smoking &avoid allergens & irritants
• 4 step of drugs

Question 11

what is the 4 steps of drugs to treat asthma?

Answer 11

step 1: short acting bronchodilators (inhaled prn)
step 2: add an inhaled steroid (inhaling so delivering locally into respiratory tract so decreases systemic effects (bad side effects)
step 3: add long acting bronchodilator to steroid
step 4: -short course steroid (ORAL)
-add 3rd drug leukotrine receptor antagonist(blocks inflm, leukotrine mediates allergic response, blocking from happening) or theophyline (potent bronchodilator)

Question 12

early phase of asthma (simple)

Answer 12

• allergen enters (mast cell already sensitized to allergen)
• Mast cells–release histamine, leukotrines, interleukings & prostaglandins causing:
• bronchospasm and
• infiltration of inflammatory cells with causes release of cytokines, interleukins, & other inflammatory mediator causing airway inflammation

Question 13

late phase of asthma (simple)

Answer 13

airway inflammation which causes edema, impaired mucociliary function, & epithelial injury, causing airflow limitation this can also lead to increased airway responsivness

Question 14

Acute phase response

Answer 14

• happens right away 5-10 min
• prior sensitization to allergen (type 1 hypersensitivity)
• subsequent exposure–allergen binds to igE on mast cells causing mediator release cause inflm
• mediators open intracellular junctions and allergen enters submucosa
• increased permeabliity and increasd mucus secretion causes edema of airway
• bronchospasm via parasympathetic ns)
• dyspnea & wheezing
• a/w constriction
• can last up to one hour

Question 15

Late phase response

Answer 15

• peaks 4-8 hrs post exposure
• can last days to wks
• influx of inflm cells (via chemotaxis)–causing epithelial damage(which will not be reversible)–decrease in mucociliary function (prone to recurrent infections) and hyperesponsiver airways (new triggers-stimuli that were not triggers become triggers, frequent severe episodes)

Question 16

what is a theory about asthma

Answer 16

• b adrenergic receptors cause bronchodilation
• a adrenergic receptors cause bronchoconstrction
• mediated via cAMP (cyclic AMP) which assists in balancing the 2 responses
• theory: is that lack of b receptor stimulation in asthma (we know that if it is involved it plays a minor role because type 1 hypersensitvity and inflm plays more of a role)

Question 17

b adrenergic receptors cause

Answer 17

bronchodilation (Adrenalin binds to receptors & causes smooth muscles to relax)

Question 18

a adrenergic receptors causes

Answer 18

bronchoconstriction