Asthma Flashcards
Essentials of asthma diagnosis
Reversibility of airflow obstruction, either spontaneously or following bronchodilator therapy
Limitation of airflow on pulmonary function testing or positive broncho-provocation challenge [methacholine challenge]
What changes occur with the walls of the airway with asthma?
Walls become inflamed and thickened + tightened smooth muscle
How does exposure to allergens trigger asthma?
Mast cells release leukotrienes which contribute to smooth muscle constriction
Characteristic findings in sputum or bronchoalveolar lavage in prolonged status asthmaticus
Curschmann spirals — extrusion of mucus plugs from subepithelial mucus gland ducts or bronchioles
Charcot-Leyden crystals — composed of protein called galectin 10
What is the strongest predisposing factor to developing asthma?
Atopy
Triggers include exposure to inhaled allergens — dust mites, cockroaches, seasonal pollens
Atopic triangle = Asthma, allergies, eczema — if there is a history of one, there are likely others
How is COPD differentiated from bronchial asthma based on FEV1 and FEV1/FVC ratio return to normal?
After drug therapy, these values should normalize in an asthmatic patient [asthma is considered reversible]
There is unlikely to be improvement in a pt with significant COPD
In differentiating asthma from COPD, what are some key indicators that it is asthma?
Wheezing (especially in children — COPD is usually diagnosed later)
Hx of cough or recurrent wheezing, difficulty breathing, chest tightness
Symptoms occur/worsen in presence of exercise, viral infection, change in weather, strong emotional expression, menstrual cycles, or potential allergens
Symptoms occur/worsen at night (awakening patient)
Asthma typically displays on flow-volume loop with ________-appearance
“Scooped out”
If you have a patient who appears to have asthma, but they are not responding to asthma medications — and spirometry shows truncated inspiratory loop (and no “scooped out” appearance that would indicate asthma), what diagnosis should you be considering?
Vocal cord dysfunction
The rescue medication for asthma always includes what class?
Short acting beta2 agonist — likely albuterol or levalbuterol
What are the long term control medications for asthma?
Inhaled corticosteroids
Leukotriene modifiers
[other options include inhaled LABAs, cromolyn and nedocromil, tiotropium, methylxanthines, immunomodulators]
Signs/symptoms that respiratory arrest is imminent
Breathlessness at rest
Not able to speak
Appear drowsy or confused
RR >30/min (or in infants >60/min)
Unable to recline
Paradoxical thoracoabdominal movement
Wheezing absent, bradycardia
FEV <25%, PaO2 <60, possible cyanosis, PCO2>42, O2 sat <90
When an asthma patient goes from the _______ to the _____ category, it is an indication for long term preventative medicine like an ICS
Intermittent; persistent
Symptoms, nighttime awakenings, SABA use, and interference with normal activity associated with asthma classified as intermittent
Symptoms <2 days/week
Nighttime awakenings <2x/month
SABA use <2 days/week
No interference with normal activity
An asthma patient’s risk is based on exacerbations requiring oral systemic corticosteroids. What are the criteria for intermittent vs. persistent classification?
Intermittent risk = 0-1x/year
Persistent = 2+/year