Asthma (Newman) Flashcards
What is asthma?
- episodic or chronic Sx of airflow obstruction - reversibility of airflow obstruction, either spontaneously or following broncho dilator therapy
How is asthma diagnosed?
- limitation of airflow on pulmonary function testing OR - positive broncho-provocation challenge (methacholine challenge)
Clinical Sx of asthma (5)
- cough - wheezing - chest tightness - prolonged exhalation - shortness of breath
Chronic asthmatic airway findings (5)
1) thickening of airway wall 2) sub-basement membrane fibrosis 3) increased vascularity 4) increase size of submucosal glands and number of goblet cells 5) hypertrophy of bronchial wall muscle
Asthmatic airway during acute attack
- bronchiole wall inflamed and thickened - tightened smooth muscle
How can exposure to allergens trigger asthma?
allergen activates TH2 cells to activate B cells which recruit mast cells (histamine) to activate eosinophils
Two findings seen in prolonged status asthmaticus
1) curschmann spirals (mucus plugs) 2) charcot-leyden crystals (eosinophil protein galectin-10)
Strongest predisposing factor for asthma
- atopy (heightened response with exposure to inhaled allergens –> dust mites, cockroaches, seasonal pollens)
Difference between asthma and COPD
with asthma: - FEV1 and FEV1/FVC ratio generally return to normal with drug therapy - Symptoms occur/worsen at night and wake up patient
Asthma Flow volume loop pre and post bronchodilator
Flow volume loop with vocal cord dysfunction
usually with tall, thin, young women who are SOB with exertion
First line quick relief asthma medication
Beta 2 agonists
- SABA (albuterol or levalbuterol)
Preferred Step 2 asthma treatment
Low-dose inhaled corticosteroid
- fluticasone
- beclomethasone
- budesonide
leukotriene modifier drugs
Leukotrinene receptor antagonists
- montelukast
- zafirlukast
5-lipoxygenase inhibitor
- Zileuton
Where are leukotrienes released from?
mast cells
Symtoms (3) respiratory arrest is imminent
breathlessness while at rest
silent
drowsy or confused
Signs (6) respiratory arrest is imminent
RR >30/min
unable to recline
paradoxical thoracoabdominal movement
absent wheezes
bradycardia
absence of pulsus paradoxus = resp muscle fatigue
Asthma classification of child that uses SABA a couple times a week, maybe before exercise or at night
intermittent
classification of asthma with 2 or greater attacks in past 6-12 months requiring systemic steroids
persistent
Patient uses SABA PRN, but asthma status gets worse with seasonal changes. What is the next step?
Add low dose inhaled corticosteroid
Stepwise approach for asthma therapy (first 4 steps in age 0-4)
1) SABA as needed
2) low-dose ICS
3) medium-dose ICS
4) medium-dose ICS and LABA -OR- montelukast
*ALSO see specialist at step 4
how frequently can a SABA be taken?
up to 2 treatments, 20 minutes apart of 2-6 puffs
Levels of asthma action plan
Green zone: child is well with no asthma Sx even during play
Yellow zone: child is not well and has asthma sx
Red zone: child feels awful with dangerous Sx
Describe well controlled asthma (5 things)
1) Sxs less than 2 days per week
2) Awakened at night less than 2x per month
3) no interference with activity
4) SABA use 2 or less days per week
5) FEV1 >80% of predicted
