Managing Asthma Exacerbations in the ED: All That Wheezes

-Case-
It’s 2 AM, and the respiratory therapist flags you down. A 28-year-old man with a history of asthma is gasping for air in Room 3. He’s using accessory muscles, can barely speak, and is clearly struggling. He’s satting at 89% on room air, and you can hear audible wheezing on auscultation of his lungs. 

-Evaluation-
Asthma exacerbations are episodes of airway inflammation, bronchospasm, and mucus plugging that lead to decreased airflow and respiratory distress. Severity varies widely, so the first step is assessing how sick your patient is.

• Mild to moderate exacerbation: dyspnea, wheezing, often still able to speak in full sentences; normal or mildly low O2 sats
• Severe exacerbation: marked dyspnea, speaking in phrases, accessory muscle use, hypoxia, tachypnea, tachycardia
• Impending respiratory failure: silent chest, altered mental status, bradycardia, hypercapnia

Key exam findings:

• Wheezing (though its absence doesn’t rule out severe asthma!)
• Prolonged expiratory phase
• Accessory muscle use
• Decreased air movement in bad cases

Workup (this is a clinical diagnosis): 

• CXR usually not needed unless you suspect alternative diagnoses (pneumonia, pneumothorax)
• ABG may be helpful if there is concern for respiratory failure (elevated CO2 is a red flag!)

-Management-

• Oxygen if hypoxic
• Albuterol/ipratropium (Duoneb) nebulizers back-to-backs q20 minutes
• Steroids: IV methylprednisolone or dexamethasone, PO prednisone if mild and can comfortably tolerate oral meds
• Magnesium sulfate IV for severe exacerbations
• Noninvasive ventilation (BiPAP) may help bridge some patients, but prepare to intubate if needed

Avoid sedatives unless intubating!

Disposition:

• Mild: observe and discharge if improved after treatment
• Moderate to severe: admit, especially if persistent symptoms, hypoxia, or poor response to initial therapy
• Impending respiratory failure: ICU and early airway management

-Fast Facts-

• Elevated CO2 is a bad prognostic sign for impending respiratory failure
• Mg can be a lifesaver in severe cases
• Steroids take hours to work – give them early!

Asthma attacks can spiral fast. Recognize early warning signs like inability to speak, silent chest, or altered mentation. Start with bronchodilators, don’t delay steroids, and escalate quickly if there’s no response. In the ED, seconds count – and sometimes the best sound is hearing that wheeze return.

Want to learn more? Read our in-depth study guide on this topic!

Cheers,

Tamir Zitelny, MD

-References-

1. Rabe KF, Adachi M, Lai CKW, et al. Worldwide severity and control of asthma in children and adults: the Global Asthma Insights and Reality surveys. J Allergy Clin Immunol. 2004;114(1):40-47. doi:10.1016/j.jaci.2004.05.013
2. Rodrigo GJ, Castro-Rodriguez JA. Anticholinergics in the treatment of children and adults with acute asthma: a systematic review with meta-analysis. Thorax. 2005;60(9):740-746. doi:10.1136/thx.2005.042432
3. Rowe BH, Bretzlaff JA, Bourdon C, et al. Magnesium sulfate for treating exacerbations of acute asthma in the emergency department. Cochrane Database Syst Rev. 2000;(2):CD001490. doi:10.1002/14651858.CD001490
4. Cydulka RK, Emerman CL, Schreiber D, et al. Emergency department management of acute asthma: an evidence-based review. Ann Emerg Med. 1998;31(4):543-556. doi:10.1016/S0196-0644(98)70373-5
5. McFadden ER Jr. Acute severe asthma. Am J Respir Crit Care Med. 2003;168(7):740-759. doi:10.1164/rccm.200301-030SO