Asthma exacerbations can be life-threatening, with 25,000 to 50,000 such patients per year requiring admission to an ICU in the United States. Appropriate triage of life-threatening
asthma is dependent on both static assessment of airway function and dynamic assessment of response to
therapy. Treatment strategies focus on achieving effective bronchodilation with inhaled β2-agonists,
muscarinic antagonists, and
magnesium sulphate while reducing
inflammation with systemic
corticosteroids. Correction of
hypoxemia and
hypercapnia, a key in managing life-threatening
asthma, occasionally requires the incorporation of noninvasive
mechanical ventilation to decrease the work of breathing. Endotracheal intubation and
mechanical ventilation should not be delayed if clinical improvement is not achieved with
conservative therapies. However,
mechanical ventilation in these patients often requires controlled
hypoventilation, adequate sedation, and occasional use of muscle relaxation to avoid dynamic hyperinflation, which can result in
barotrauma or volutrauma. Sedation with
ketamine or
propofol is preferred because of their potential bronchodilation properties. In this review, we outline strategies for the assessment and management of patients with acute life-threatening
asthma focusing on those requiring admission to the ICU.