Mechanical ventilation in severe asthma.

Asthma is a cause of severe morbidity and mortality in the United States. Severe acute asthma accounts for over one million emergency room visits per year (1). The vast majority of patients presenting with acute asthma can be successfully managed with β2-agonist bronchodilators, corticosteroids, and oxygen. Despite maximal medical therapy, it is estimated that 1– 3% of patients with severe asthma may require endotracheal intubation and mechanical ventilation during their hospital course (2,3). For the purposes of this chapter, severe asthma requiring mechanical ventilatory support will be referred to as status asthmaticus (SA). It appears that the number of patients progressing to SA is increasing, especially in the United States (4,5).