8. Asthma Flashcards
what is the end result of all types of asthma?
cellular inf of the airway, enhanced bronchial responsiveness, airflow obstruction.
what is atopy?
tendency to form IgE antibody to inhaled allergens (like pollen, dander, dust mites)
on gross appearance, what do asthmatic airways look like?
narrower, reddened, edmatous
what cell types has the airway been invaded by in asthma?
eosinophils, Th2 cells.
what do these invading cells do?
cause local tissue damage, release cytokines which cause the inflammation
what is the airflow appearance of an asthmatic?
limited airflow, reduced FEV1, reduced ratio, low PEF. all this caused by inflammation of the airway.
what is the primary reason for airflow restriction?
bronchoconstriction. resulting from airway hyperresponsiveness (AHR)
things that will trigger asthma?
- allergens
- viral infections
- exercise
- physical factors: cold, dry, humid air, fumes
- occulational factors/allervens
clinical presentation of asthma?
wheezing, dyspnea, cough. may be worse at night.
physical findings of asthma?
expiratory wheezes, hyperinflation, accessory muscle use, air hunger
how will an asthmatic look on spirometry?
normal inspiratory loop. on expiration there may be a decr FEV1 and low ratio. but spirometry may look normal, so can’t rule out asthma. after a SABA there may be an improvement in FEV1 which supports an asthma dx.
what is the methacholine inhalation challenge?
successive concentrations of methacholine are delivered, and spirometry is done after each dose. causes bronchoconstriction in pts with AHR. the smaller the dose of methacholine that yields a drop in FEV1, the more severe the AHR.
comorbidities with asthma?
- rhinosinusitis. causes more difficult asthma control
- GERD. reflex bronchospasm w acid reflux?
- obesitity, obstructive sleep apnea
- triggers/allergens
how the measuring the exhaled Nitric Oxide help with asthma diagnosis?
biomarker that reflects lower airway inflammation, correlates with degree of eosinophil inflammation
what are the 2 divisions of pharm therapy for asthma?
rescuer, controller