asthma Flashcards
define asthma and risk factors?
chronic airway inflammation that presents as expiratory airflow limitation and respiratory symptoms
atopy (allergic rhinitis, eczema)
allergies
genetic predisposition
asthma triggers? brief pathophysiology and type of hypersensitivity reaction?
dust, pollen, animal dander, mold, occupational allergens (worse in weekdays not weekends)
viral respiratory infections, physical exertion, drugs like NSAIDs aspirin and beta blockers
bronchial hyperresponsiveness, inflammation, and obstruction -> expiratory limitation. IgE-mediated type 1 hypersensitivity
symptoms and diagnosis? what is used to monitor response to treatment in acute asthma attack?
dry cough worse at night, chest tightness, SOB, diffuse expiratory wheeze
diagnosis:
1. clinical symptoms of asthma
2. PFTs (spirometry) showing obstructive pattern that is reversible with bronchodilator (B2 agonist)
low FEV1 and low FEV1/FVC ratio (less than 70). Bronchodilator -> 12% AND 200ml increase in FEV1.
if spirometry inconclusive, do bronchial challenge test (methacholine challenge test) to test bronchial hyperresponsiveness. If they have asthma, they will experience the symptoms. Then use PFT
Use peak flow meter
treatment options?
SABA PRN
SABA + low dose ICS PRN
LABA + low dose ICS
LABA + medium dose ICS
LABA + high dose ICS plus LAMA (antagonist)
SABA= albuterol
ICS= budesonide
LAMA= tiotropium bromide
LABA= formoterol
LABA and LAMA shouldn’t be used without ICS
symptoms of acute asthma attack
severe: tachycardia, RR >30, PEFR <50% of predicted or best
life threatening: silent chest, bradycardia, no wheeze, PEFR<33%
also respiratory failure
management?
do chest xray to rule out DDx, ABG for severity, PEFR for assessment of treatment
give oxygen therapy for all patients
then depending on severity:
severe to life threatening:
inhaled SABA (albuterol) plus inhaled SAMA (ipratropium bromide) plus oral or IV glucocorticoids plus single dose IV magnesium sulfate
ICU admission and intubation with mechanical ventilation as last resort
LAMA and LABA are contraindicated in acute settings
