Asthma Flashcards
Asthma Definition
Episodic airway obstruction and hyperresponsiveness usually accompanied by airway inflammation
1. Episodic
2. Obstruction (reversible)
3. Hyperresponsiveness
4. Inflammation
Asthma has a high incidence in what population?
Puerto rican
Natural History of asthma in adults
o Females > Males
o Perimenopause
o If start wheezing in adolescence or adulthood- likely to persist but
likely to not progress markedly in severity
Atopy:
genetic predisposition to develop
specific immunoglobulin E (IgE) antibodies directed against common environmental allergens
Atopic triad
Asthma
Eczema
Allergies
Serum levels of ____ correlate closely with
the development of asthma
IgE
Environmental risk factors of asthma
- Allergen exposure in those with a predisposition to atopy
o 50% have atopy (high IgE) allergic sensitization
o Most common allergens: house dust mites, indoor fungi, cockroaches, and
indoor animals - Occupational exposure
- Air pollution
- Infections (viral and Mycoplasma) RSV, rhinovirus
Lifestyle Risk Factors for asthma
- Tobacco- maternal smoking, secondhand, and active (4x risk)
- Obesity - dose-dependent effect of body mass index (BMI) on
asthma risk - Diet
o Vitamin D Def- also maternal Vit D def (Studies not
statistically sig but show evidence)
Elements of Asthma (pathophysiology)
o Bronchoconstriction
o Airway edema and inflammation
o Airway hyperreactivity
o Airway remodeling
Presentation of Asthma
o Episodic wheezing
o Shortness of breath
o Chest tightness
o Cough
o Sxs vary in intensity and over time
o Often worse at night
o Triggers
Triggers of asthma can include:
Environmental/occupational allergens
Cold, dry air
Emotion
Infections
Inhaled irritants
Exercise
Aspirin, NSAIDS
GERD
Allergic rhinitis
Work-up for asthma
o History & Exam
o Pulmonary function tests- spirometry
o confirm and quantify the severity and reversibility of airway
obstruction
o methacholine challenge testing option if PFTs normal but suspect
stil
o X-ray to exclude other causes dyspnea
o Allergy testing in kids may help reduce allergic component
FEV1 vs FVC
o FEV1: the forced expiratory
volume in one second
o FVC: the total amount of air
that can be expelled from
full lungs
What can pulmonary function tests tell you about asthma?
- Pre-bronchodilator:
- ↓ FEV1, ↓FEV1/FVC <0.8
- FVC may be low
- Post-bronchodilator
- FEV1 or FVC ↑ > 10-12%, sxs reversible
How often should spirometry be done for asthma?
Spirometry at diagnosis, 3-6 mos, and periodically as needed
Treatment goals for asthma
- Goal #1: minimize
chronic sxs that
interfere with life - Goal #2: reduce
exacerbations
Criteria of good asthma control:
- Symptoms of asthma requiring quick-reliever medication no more than two days per week
- Night-time awakenings no more than two nights per month
- Lung function (PEF or FEV1) within the normal range (or within 20 percent of the patient’s personal best value)
- No more than one exacerbation in the past year requiring urgent care and/or oral glucocorticoids
Clinical Course of asthma
o Often resolves in kids
o 1 in 4 kids persist with wheezing into adulthood or relapse
o Good prognosis with treatment adherence and periodic eval
o Some pts have permanent airway remodeling and obstruction
Complications of Asthma
o Exhaustion
o Dehydration
o Airway infection
o Tussive syncope
o Pneumothorax occurs but is rare
o Acute hypercapnic and hypoxemic
respiratory failure occurs in severe
disease
SABAs (short-acting beta agonist)
- Albuterol
- Levalbuterol
LABAs
- Salmeterol
- Formoterol
LAMAs
- Tiotropium Spiriva
LTRA (Leukotriene
receptor antagonist)
- Monteleukast Singulair
ICS
- Fluticasone
- Budesonide
- Ciclesonide
Stepping Down guidelines in Asthma
- After stable for 3-6 mos, may step down
- Reduce cost, side effects
Patient Education for Asthma
o WHAT is asthma
o WHEN medications
o WHY medications
o HOW to take medications
o Avoidance of triggers- work exposure, allergens, dust
mites/pets, food, don’t avoid exercise (pre-treat)
o Action plan
o Self monitor via sxs or peak flow meter
MDI (Metered dose) guidelines:
Shake inhaler, exhale, slow & deep
breath, hold for 5-10 sec
DPI (dry powder) guidelines
Exhale, quick deep breath 3 sec, hold for 5
-10 sec
Peak Flow Meter use
o Max exhalation after full
inspiration
o Correlates with FEV1
o Max effort- coach pt
o Perform 3 times; keep highest
o Compare to standardized chart
or patient personal best
Exacerbation guidelines if 80%-100% of PEF from baseline:
use SABA as prescribed
Exacerbation guidelines if 50% of PEF is severe
Go to ER
Exacerbation guidelines if 50-80% of PEF
SABA 2-6 puffs Q 20 min x 1 hr, reassess
Good, incomplete and poor response in asthma exacerbations
o Good response- No symptoms, Peak Flow reading of >80% personal best:
continue SABA every 3-4 hours PRN for 24-48 hours, frequently reassessing
with Peak Flow.
o Incomplete response- Persistent wheezing and Peak Flow reading of 50-80%
personal best: Continue SABA as above and add PO corticosteroid for 5-7
days.
o Poor response- Marked wheezing and Peak Flow reading of <50% personal
best: Repeat SABA immediately, go to ER (consider ambulance), and PO
corticosteroid should be initiated (at least)
Asthma Attacks: Prevention
o Control triggers
o Stay on medicine
