Asthma Flashcards
Test 3
Where is the greatest resistance in the lungs?
Medium bronchi
Has contraction from vagus nerves and ciliated cells
Describe smokers lungs
They lose cilliated cells that mutate to cells more adaptive to abrasions. This causes mucus to fall into lungs, and why they develop coughs, especially in the morning.
______ has cartilage, and ________ does not.
Bronchi
bronchioles
What is an obstructive disorder?
hyperactive airways
airway more collapsed
excessive mucous
airway overreacts to vagus nerve stimulation
-Asthma, Chronic bronchitis, emphysema, COPD
How do Obstructive disorders present?
Dyspnea
wheezing
Asthma is the most common in_____
Children
Describe the histamine challenge
In symptom-free adults with asthma, if you spray histamine in the air, you will see a decrease in exhale force
What is increasing obstructive diseases?
Infant second hand smoke
Worsening air quality
Hygiene hypothesis
What is hygiene hypothesis?
Not exposing children to enough, allergens and germs, therefore causing their immune system to not act normally
Also increasing the amount of auto immune diseases
Describe Asthma
S/S: Wheezing, breathlessness, chest tightness, coughing (esp. night/morning), airway inflammation, smooth muscle contraction, mucosal thickening.
-increased WBC, bronchoconstriction, mucosal edema, and mucus hypersecretion. even when airway is relaxed
triggers: allergens, respiratory infections, irritants, certain medications, exercise, gastroesophageal reflux disease, anxiety, and stress
How do you Dx Asthma?
- FEV1: Forced expiratory volume - Inhaled small concentration of histamine and compare exhale over 1 second to prior
- PEF: Peak expiratory flow - max flow of forced expiration based on sex/age
Dead space in lungs ______ with age
increase
What is the Tx for Asthma?
Beta-2 specific agonist
Anti-inflammatory as adjuncts
What are the 2 types of asthma?
Intrinsic: genetic factors/alleles more inclined to asthma
Atopic (extrinsic): reactions that occur when exposed to certain allergens
Describe what happens in an Atopic (extrinsic) reaction
Dendrite cells in the respiratory tract + allergen -> T Helper cell binds to the MHC2-R -> this produces IL4 -> IL4 binds with B cells -> These cells produce plasma cells or antibodies -> IgE which elicits an allergic response then binds to mast cells -> The next time this person is exposed to this allergen the mast cell will degranulate and cause allergic response including: mucus, secretion, capillary, dilation, allergic response, itching, hayfever, anaphylaxis
What mediators are responsible in asthma?
Early: Histamines, leukotrienes, prostaglandins = bronchoconstriction & vascular leakage
Late: Leukotrienes, platelet-activating factor, tryptase = sustained bronchoconstriction, cellular infiltration, and mucus hypersecretion
When does late response occur in asthma?
2-8 hours
What cells produce mucous? and where are they located
Goblet cells
GI and respiratory tract
What is mucous made of?
95% water
5% glycoproteins
What does mucus do?
Grabs irritants before they go down into the lungs
Describe the immune response to allergens as it pertains to the following cells: dendritic cells, T cells, B cells, plasma cells, mast cells, neutrophils, and eosinophils
Dendritic cells: Process and present allergen to T cells
T helper cells: Release IL-4 to activate B cells
B cells: Produce IgE antibodies that bind to mast cells
Plasma cells: Secrete IgE antibodies
Mast cells: Degranulate and release histamine, leukotrienes, prostaglandins
Neutrophils and eosinophils: Release proteases that contribute to inflammation
List the primary pathways of the arachidonic acid cascade, and its main products
Lox pathway: Produces leukotrienes
Cox pathway: Produces prostaglandins
Describe Coup
Common in 6mon - 5years
Viral RSV
Seal like barking cough
How do you treat Croup?
Nebulized Epi
Humidity
Identify ANS effects on airwDesay diameter.
Parasympathetic (vagus nerve): Bronchoconstriction through vagal stimulation & Ach
Sympathetic: Bronchodilation through beta-2-R and relaxation of smooth muscle
Describe the strategies of drug treatment of asthma and COPD and the two broad categories.
Short-term relievers (bronchodilators): Sympathomimetics like beta agonists
Long-term controllers (anti-inflammatories, antibodies, leukotriene inhibitors): Corticosteroids and other injectable medications
List the major classes of drugs used in asthma and COPD
Short-term relievers: Beta-agonists, methylxanthines, anticholinergics/antimuscarinics
Long-term controllers: Corticosteroids, leukotriene inhibitors, antibodies
What is COPD?
Chronic bronitis: cough & hypersecretion of mucus for 3 months of the year for 2 years
and Emphysema: enlargment of gas exchange airways, destruction of alveolar, loss of elastic recoil -> distended bronchioles and alveolus
Describe the mechanisms of action of these drug groups
Beta-agonists, methylxanthines, anticholinergics/antimuscarinics, Corticosteroids, leukotriene inhibitors, antibodies
Beta-agonists: Relax airway smooth muscle and inhibit substances from mast cells
Methylxanthines: Inhibit phosphodiesterase, increase cAMP
Anticholinergics/Antimuscarinics: Block muscarinic receptors, inhibit bronchoconstriction
Anti-inflammatories (corticosteroids): Reduce inflammation by suppressing the immune response
Leukotriene inhibitors: Block leukotriene synthesis or receptors
Antibodies: Block cytokines/mediators (e.g. dupilumab blocks IL-4)
Identify treatment considerations for specific patients with mild, moderate, or severe asthma and/or COPD.
Mild asthma: Short-term relievers as needed (i.e. rescue inhalers)
Moderate-severe asthma: Short-term relievers plus long-term controllers -> inhaled corticosteroids & PO leukotriene pathway inhibitor
COPD: Combination of bronchodilators and anti-inflammatories -> PO/inhaled corticosteroids, anti-IgE antibody
List Beta-2 Specific Agonist
Albuterol: 30 mins - 4 hrs
Lipid soluble & up to 12 hr effects (LABA):
Salmeterol
Formotorol
List Beta Agonist
Epinephrine - SQ or inhaled; max dilation in 15mins
Isoproterenol: not used much -> fatal arrhythmias
How much of an inhaled dose actually gets into the airway? what is most important when taking an inhaler?
10-20% of dose gets to patient
training the patient to use an inhaler
List Methylxanthines
Theophylline (tea or purified)
Theobromine (chocolate)
Caffeine (coffee)
List Antimuscarinics
Atrovent/Atropine
Inhaled ipratropium bromide (longer acting than atrovent)
Describe purified Theophylline
narrow therapeutic index (5-20mg/L)
used for COPD
What route for steroids do you want to use and why?
Inhaled
targets lungs directly
List Corticosteroids
Prednisone
Fluticasone (IM, aerosol)
Blocks transcription/translation
What are adverse effects of corticosteroids?
Suppress immune system
Osteoporosis
Decrease growth in children
Oral yeast infection
List Leukotriene pathway inhibitors
Montelukast
Improve aspirin induced asthma
Use as adjunct
Inhibits 5-lipoxygenase & receptor binding
List Monoclonal antibodies to IgE
Omalizumab
Prophylaxis
Once a month - does not activate the IgE on mast cells
What does a Nebulizer do?
Make particles small to get through to where they need to be
