Treatment of Acute, Severe Asthma

Abstract

Asthma is a common respiratory disorder and, thus, a common cause for hospital admissions. It occurs in all age groups and affects both sexes, but for reasons not well understood women tend to have more severe asthma than men. The severity of asthmatic episodes ranges from mild and nearly inapparent to severe, life-threatening and occasionally fatal. In 1975 it was estimated that asthma was the cause of death in 2000 patients in the United States. 1 Scoggin and coworkers 2 reported their experience with status asthmaticus in one general hospital. Between 1967 and 1975, there were 811 adults admitted for asthma, of which 21 had episodes that were severe enough to require mechanical ventilation and eight died. Other studies have reported death rates from 0 to 27% in those asthmatics requiring mechanical ventilation. 3,4 Because asthma is a reversible condition, each of these deaths should be considered a preventable event.The basic principles of pathophysiology and pharmacology are the same for the full spectrum of asthma. When assessing and managing severe asthma, two kinds of objective evaluations are important to grade the severity of the asthmatic episode. The first is to quantify the degree of airway obstruction and its effect on gas exchange through the measurement of airflow rates, arterial blood gas tensions, and pH. The second is to determine the response of these parameters to the administration of bronchodilating agents, which provides information for subsequent management. In regard to the second objective evaluation, those patients with acute attacks of asthma who do not respond promptly to standard doses of bronchodilators (beta-adrenergic agents, intravenous aminophylline) and rehydration represent a category of patients commonly designated as "status asthmaticus." When this occurs, it is critical that other therapeutic interventions be initiated. There is no oversimplification in the statement regarding status asthmaticus, "the longer it lasts, the worse it gets, and the worse it gets, the longer it lasts."