The Management of Acute Severe Asthma

Abstract

Acute severe asthma exacerbations resulting in emergency department visits and hospitalization usually constitute a failure of long-term control therapy. However, even patients with relatively mild asthma can have severe life-threatening episodes. In both children and adults, viral respiratory infections are the major triggering event, although outbreaks of severe asthma have been associated with high concentrations of aeroallergens. Patients should be provided with written action plans on what to do for acute deterioration, and more severe patients may keep prednisone at home to begin after consultation with their physician. The primary therapy of acute asthma exacerbations remains frequent administration of aerosol β₂-agonists and systemic corticosteroids for those patients not fully responding to the β₂-agonists. Mild exacerbations may be treated with an increased dosage of inhaled corticosteroids. Patients at risk for acute exacerbations may benefit from peak flow measurement, particularly those who have difficulty perceiving airway obstruction. It is recommended that patients remain on full dose of prednisone until they achieve 70-80 percent of predicted normal or personal best peak flow. In the emergency department, the use of β₂-agonists by metered-dose inhaler and holding chamber is as effective as nebulizer if given in a sufficient dose 6-10 puffs equivalent to 5 mg via nebulizer. In those patients not responding completely, the addition of ipratropium bromide has shown to produce additive bronchodilation and reduce hospitalizations. Other therapies such as magnesium sulfate, intravenous β₂-agonists, heliox and ketamine have been used, but data demonstrating efficacy are insufficient to warrant recommending their general use.