Asthma
Intermittent, reversible, obstructive lung disease characterized by inflammation and hypersensitivity, leading to:
- Vasodilation – increases the thickness of the mucosa, both by vascular engorgement and by increased interstitial liquid volume
- Bronchospasm
- Edema
- Mucous secretion
Caused by:
- Genetics – 11 genes are directly related
- Triggers – air pollution, indoor/outdoor allergens, respiratory tract infection, nose and sinus problems (rhinitis), food sensitivities, exercise, stress, GERD
Risk factors
Asthma risk factors:
1. Gender (women)
- Age
- Genetics
- Exposure – environment, occupation, infection
- Medical history – GERD, obesity, allergies, chronic rhinitis
Diagnosis
Detailed medical history – family, occupational, environmental
Physical examination – especially wheezes, hyperresonance
Pulmonary function test (PFT)
CXR – hyperinflation (chest trapping due to obstructed bronchioles)
Serum IgE – looking for allergic response
Key symptoms
S/S (increase the probability of asthma diagnosis):
1. Cough
- Recurrent wheeze
- Recurrent difficulty breathing
- Recurrent chest tightness
- Symptoms occur/worsen in the presence of infection, exercise, inhalant allergen, irritants, changes in weather, stress
- Symptoms occur/worsen at night
**Diagnosis is confirmed with PFT
Clinical manifestations
Early S/S:
- Cough
- Wheezing
- Diminished breath sounds
- Chest tightness
- Restlessness
- Hyperresonance
Late S/S:
- Tachypnea
- Tachycardia
- Use of accessory muscles
- Decreased O2 sat.
- Cyanosis
Airway remodeling
Refers to the structural changes in the airway due to asthma (can occur in all degrees severity):
- Loss of epithelial integrity
- Destruction of ciliated cells
- Increased smooth muscle mass – does NOT allow for ventilation
- Thickening of the basement membrane
Prevention:
- Asthma Action Plan
- Prescribed meds. (corticosteroid)
- Effective treatment of allergic rhinitis
Asthma basis of classification
Classification (S/S increase in frequency with severity):
- Intermittent
- Mild persistant
- Moderate persistant
- Severe persistant
Impairment:
- Symptoms
- Night awakening
- Short-acting beta agonist (SABA) – used for symptom control (i.e. Albuterol)
- Interference in activity
- Lung function – FEV1 and peak expiratory flow
Management
PRIMARY CARE:
1. Reduce impairment – prevent symptoms, limit use of SABA (albuterol), and maintain normal lung function and activity levels
- Reduce risk – prevent exacerbations, minimize need for emergency care/hospitalization, prevent loss of lung function, and minimize adverse effects of therapy
- Asthma action plan
- Smoking cessation
- Identify and eliminate triggers
- Pt/family education
- Drug therapy
- Identifying resources
CLINICAL MANAGEMENT – Re-evaluate 1-3 mos. after diagnosis, then every 3-12 mos. (but 1 week after severe exacerbations)
Asthma action plan
Includes: Usual medication, when/how to increase medication, and how to access medical care if symptoms fail to improve
ZONES:
1. Green (Doing well) – No cough/wheeze/chest tightness/SOB, and can do all usual activity; Take prescribed LABA
- Yellow (Worsening) – Some cough/wheeze/chest tightness/SOB, walking at night, and can do some usual activities; Add quick relief medicine
- Red (Medical alert) – Very SOB, quick relief meds. do NOT help, and cannot do usual activities; No symptom improvement after 24 hrs. (medical help is required)
Acute management
Managing acute exacerbation:
1. Call EMS
- O2 sat. monitoring
- ABGs
- Meds – IV corticosteroid, ipratropium bromide, inhaled beta agonist (albuterol)
- IVF
Pt/family education
Self-management:
1. Eliminate/reduce known triggers – Consider replacing carpets with hard floors, pets, bedding, cleaning/vacuuming regularly, diet change/weight management, and stress management
- Know prescribed meds. – relievers, preventers, and symptom controllers
- Know when in trouble – i.e. peak flow
Peak flow meter
Personal best (100%) is determined by age, height, and gender
ZONES:
- Green (80-100%)
- Yellow (50-80%)
- Red (<50%)
