Management of Life-Threatening Asthma: Severe Asthma Series

Abstract

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.

Keywords: critical care medicine; life-threatening asthma; mechanical ventilation; respiratory failure; sedation.