Asthma Flashcards
what is the atopic triad
asthma, allergic rhinitis, atopic dermatitis (eczema)
describe the allergic asthma phenotype in terms of treatment
usually responds well to ICS
describe the non-allergic asthma phenotype in terms of treatment
usually less response to ICS
when does allergic asthma usually present
childhood, associated with PMH or FH of allergic disease such as eczema, allergic rhinitis, or food and drug allergy
when does non-allergic asthma usually present
adults, occupational asthma, asthma with obesity
what does the biodiversity hypothesis suggest
exposure to microbe-rich environments protects against allergic and autoimmune diseases
TH1 is what type of immunity
cell-mediated protective immunity (no allergies)
TH2 is what type of immunity
antibody mediated immunity (allergies, asthma)
who is likely to differentiate to TH1 immunity
older siblings, early daycare exposure, rural, childhood infections, microbial exposure
who is likely to differentiate to TH2 immunity
only child, widespread use of antibiotics, urban environment
describe TH1/TH2 shift
at birth, predominant TH2. As exposure to bacterial/viral infections occur, shifts towards TH1. If TH1 doesn’t mature, TH2 predominates which favors allergy, allergic rhinitis, and eczema
T2 inflammation/eosinophilic/allergic asthma is present when
at an early age
T2 asthma is associated with
atopy, allergy, elevated IgE, eosinophilia, elevated FeNO
non-TH2/non-eosinophilic asthma is present
later in life
describe some protective factors for developing asthma
being the younger sibling, natural birth, breastfeeding, higher socioeconomic status, healthy diet, low pollution rates, exercise, microbial exposures, farm living
describe some risk factors for developing asthma
asthma family history, c-section, formula feeding, sheep/hay farming, urban living, respiratory viral infections, lower socioeconomic status, obesity, use of antibiotics
what medications can be asthma triggers
ASA/NSAIDs, non selective beta blockers
which beta blockers are asthma triggers
propranolol and carvedilol
what is samter’s triad
asthma, nasal polyps, aspirin/NSAID sensitivity
how does aspirin/NSAID exacerbated respiratory disease occur
the arachidonic pathway changes: NSAIDs block COX so PGE2 not available to keep 5 lipoxygenase in check= more leukotrienes (bronchospasm, increase permeability, mucus)
3 major characteristics of asthma
chronic airway inflammation, variable degree of airflow obstruction and narrowing, bronchial hyperresponsiveness
FEV1/FVC ratio of ___ demonstrates obstruction
<70%
what will demonstrate airway reversibility after beta2 agonist inhalation
FEV1 increases by more than 12% and 200 mL
what does airway reversibility demonstrate
asthma
what does a peak flow meter measure
peak expiratory flow rate (PEFR): the fastest speed a person can blow air out of lungs after taking as big of a breath as possible
what type of inhale for MDIs and soft mist inhalers
slow and deep
what type of inhale for DPI
deep and forceful
ICS place in therapy for asthma
primary maintenance therapy, best outcomes
corticosteroids mechanism
glucocorticoid receptor agonist in the lungs to provide anti-inflammatory, immunosuppressive, and antiproliferative effects to mitigate responses to various stimuli
ICS onset of action
variable, up to 2-4 weeks for max effect
ICS side effects
oral candidiasis, URTI, sinusitis, hoarseness, cough, pneumonia
which class may slow bone growth in children
ICS
systemic corticosteroids place in therapy
reserved for poorly controlled, in the setting of an acute exacerbation not relieved by rescue agents
OCS drug interactions
CYP3A
OCS side effects
HTN, fluid retention, hyperglycemia, GI upset, insomnia, infection, adrenal axis suppression, glaucoma, pulmonary TB
OCS cautions
immunosuppressed, HTN, DM
OCS counseling
take with food
name the ICS agents
fluticasone, budesonide, mometasone, beclomethasone
name the OCS agents
prednisone, dexamethasone, methylprednisolone
name the SABAs
albuterol, levoalbuterol
SABA place in therapy
drug of choice for acute asthma exacerbations, most effective for relieving acute bronchospasm
SABA mechanism
selective B2 adrenergic agonist: binds to B2 receptors in the lungs, resulting in bronchial smooth muscle relaxation, increase cAMP
SABA onset
1-2 minutes neb, 2-5 minutes MDI/DPI
SABA duration
3-4 hours neb, <6 hours MDI
SABA side effects
tremor, tachycardia (less with levo), chest pain, hypokalemia, hypomagnesemia, hyperglycemia
SABA risk?
regular use= poor asthma control. RISK WITH SABA ONLY THERAPY
regular or overuse of SABA causes
beta receptor downregulation, lack of response, increased use
counseling: if giving albuterol with ICS in a separate inhaler
albuterol FIRST, then ICS
LABA agents
formoterol, olodaterol, salmeterol, vilanterol
LABA place in therapy
chronic therapy for asthma IN COMBINATION with ICS. monotherapy for mild COPD, combo with LAMA for persistent COPD
LABA onset
1-2 minutes formoterol olodaterol. >10 minutes salmaterol vilanterol
LABA duration
> 12-24 hours
black box warning LABA
never monotherapy for asthma!!!!!!!! LABA monotherapy is for COPD only.
important point for LABA
do not take two different LABAs. use same combination for reliever and maintenance.
SAMA agent
ipratropium
SAMA place in therapy
mainly COPD and acute asthma exacerbations (emergency)
SAMA mechanism
competitive inhibitor of cholinergic (muscarinic) receptors in the bronchial smooth muscle leading to bronchodilation
SAMA onset
15-30 minutes
SAMA duration
4-8 hours
SAMA side effects
headache, flushing, blurred vision, tachycardia, palpitations
LAMA agents
aclidinium, glycopyrrolate, tiotropium, umeclidinium
LAMA place in therapy
mainly for COPD. tiotropium for sever asthma >12 after ICS/LABA`
tiotropium duration
> 24 hours
LAMA side effects
headache, blurred vision, flushed skin, tachycardia, palpitations, acute urinary retention, cough
general cons of biologics
increased infection risk, high cost, need to avoid live vaccines
biologics place in therapy
not first line or monotherapy. decrease exacerbations. add on to standard therapy for severe asthma step 4-5 in patients with T2 phenotype. may decrease OCS dose
LTRA agents
montelukast, zafirlukast
5-lipoxygenase inhibitor
zileuton
LTRA mechanism
interfere with pathway that allows mast cells and eosinophils to release leukotriene mediators. reduce symptoms associated with allergic component of asthma: swelling and smooth muscle contraction
LTRA onset
3-4 hours
LTRA duration
up to 24 hours
LTRA side effects
URI, fever, headache, pharyngitis, cough.
FDA boxed warning for montelukast
neuropsychiatric effects
risk with zafirlukast
hepatotoxicity
methylxanthine agents
theophylline, theophylline ER
theophylline place in therapy
adjunct
theophylline mechanism
inducing smooth muscle relaxation to result in bronchodilation
theophylline side effects
caffeine-like effects at therapeutic levels: n/v, headache, insomnia. toxic level effects: persistent vomiting, arrhythmias, seizures
theophylline monitoring
narrow therapeutic window requiring blood monitoring. normal level <20 mcg/mL
chromone agent
cromolyn sodium
cromolyn place in therapy
adjunct; EIB or add on for allergic asthma
cromolyn mechanism
mast cell stabilizer: inhibits release of histamines and leukotrienes from mast cells during allergic response
anti-IgE mAb
omalizumab
omalizumab mech
inhibits binding of IgE to mast cells and basophils: thus decreases mediators of allergic response
omalizumab side effects
anaphylaxis, urticaria, thrombocytopenia, malignancy, CV
omalizumab monitoring
weight, IgE levels, platelets
IL-5 antagonists
mepolizumab, relizumab, benralizumab
IL-5 antagonist mechanism
inhibit IL-5 signaling, reducing the production and survival of eosinophils
IL-5 antagonist side effects
hypersensitivity, headache, fatigue, herpes zoster (mepolizumab), malignancy
IgG4 antibody
dupilumab
IgG4 antibody mechanism
inhibits IL-4 and IL-13 signaling/ inflammatory response by binding to IL-4Ra subunit
IgG4 antibody side effects
favorable tolerability: injection site reaction, oropharyngeal pain, eosinophilia
thymic stromal lymphopoietin blocker
tezepelumab
tezepelumab side effects
pharyngitis, arthralgia, back pain
what are some medication-related asthma risks
high SABA use >1 canister per month, not prescribed ICS, poor adherence, incorrect inhaler technique
what are some comorbidities than increase risk of asthma symptom
obesity, chronic rhinosinusitis, GERD, food allergy, pregnancy and hormonal changes
asthma control test score?
> 19/25 is well controlled. 19 or less is not controlled.
mild asthma by GINA definition
symptoms <4-5 days per week
moderate asthma by GINA definition
symptoms most days or waking with asthma >1 time per week
severe asthma by GINA definition
daily symptoms or waking with asthma >1 time per week AND low lung function
what are options for reliever treatment asthma
SABA, low dose ICS-formoterol. (alt: SAMA for acute exacerbation)
what are options for controller or maintenance asthma treatment
ICS, LABA, LAMA, LTRA, biologics
treatment for mild or moderate acute asthma exacerbation
albuterol 4-10 puffs q20min for 1 hour, continue hourly x1-3. Likely take oral corticosteroids at home.
treatment for severe acute asthma exacerbation
albuterol + ipratropium MDI or neb q20min or continuously for 1 hour, then q1-4h prn. + oral corticosteroids. adjunct (magnesium, ketamine, heliox) helpful.
treatment for life threatening acute asthma exacerbation
IV corticosteroids
treatment for green zone
take long term control agent only. uses reliever before exercise, avoid triggers.
treatment for yellow zone
increase usual reliever, contact clinician, OCS burst
role of TH2 in pathophysiology of asthma
releases IL-4 and IL-5
role of IL-4 in pathophysiology of asthma
differentiation of CD4 to plasma cells: producing IgE antibodies
role of IL-5 in pathophysiology of asthma
proliferation, activation, and survival of eosinophils
role of IgE in pathophysiology of asthma
bind to and activate mast cells
role of leukotrienes in pathophysiology of asthma
bronchoconstriction
role of TSLP in pathophysiology of asthma
inflammatory mediator in response to allergens
role of dendritic cells in pathophysiology of asthma
stimulate TH2
role of mast cells in pathophysiology of asthma
release histamine and leukotrienes
mediators of early phase allergen reaction?
histamine, prostaglandins, leukotrienes
mediators of late phase allergen reaction?
eosinophils, neutrophils, macrophages, T lymphocytes, prostaglandins, leukotrienes, thromboxones, PAF
what does airway remodeling include
fibrosis, epithelial cell injury, mucus hypersecretion, smooth muscle hypertrophy, angiogenesis
bronchoprovocation testing
patient is given methacholine, positive test is fall in FEV1 by 20%
exercise challenge test
positive if FEV1 falls 10% for adults or 12% for children
baseline eosinophil count of ____ is a predictor for T2 asthma
> 150
which DPIs could be mistaken for a MDI
respiclick, redihaler, digihaler
how to load the dose for ellipta
sliding cover down
how to load the dose for diskus and inhub
sliding lever
how to load the dose for respiclick, digihaler, redihaler
opening the cap
how to load the dose for twisthaler
twist counterclockwise
how to load the dose for flexhaler
twist as far as it goes in any direction, then back in the other direction until it clicks
how to load the dose for pressair
press the button, control window will turn green. it will then turn red if you inhaled correctly
how to load the dose for handihaler
SINGLE USE: you have to put a capsule in and puncture it. don’t swallow the capsule idiot