Clinical manifestation
- Recurrent episodes of wheezing, breathlessness, cough, and tight chest
- Expiration may be prolonged.
- Inspiration-expiration ratio of 1:2 to 1:3 or 1:4
- Bronchospasm, edema, and mucus in bronchioles narrow the airways
- Air takes longer to move out
- Most common manifestations
- Cough
- Shortness of breath (dyspnea)
- Wheezing
- Chest tightness
- Variable airflow obstruction
Complications and classification
- Mild
- Dyspnea occurs with activity and patient may feel that he or she “can’t get enough air.”
- PEF ≥70%
- Usually treated at home
- Prompt relief with inhaled SABA such as albuterol (delivered via a nebulizer or MDI with a spacer)
- Patients instructed to take 2 to 4 puffs albuterol every 20 min three times to gain rapid control of symptoms
- Occasionally short course of oral corticosteroids is needed.
- Moderate
- Dyspnea interferes with or limits usual activities.
- PEF 40%69%
- Usually requires office or ED visit
- Relief is provided with frequent inhaled SABA.
- Oral systemic corticosteroids. (Symptoms may persist for several days even after corticosteroids are started.)
- Severe exacerbations
- Respiratory rate >30/min
- Dyspnea at rest, feeling of suffocation
- Pulse >120/min
- PEFR is 40% at best
- Usually seen in ED or hospitalized
- Partial relief from frequent inhaled SABA
- Oral systemic corticosteroids. Some symptoms last for >3 days after treatment is begun.
- Adjunctive therapy: ipratropium, IV magnesium
- Life-threatening asthma
- Too dyspneic to speak
- Perspiring profusely
- Drowsy/confused
- PEFR <25%
- Require hospital care and often admitted to ICU
- Minimal or no relief from frequent inhaled SABA
- IV corticosteroids
- Adjunctive therapy: ipratropium, IV magnesium
