Skip to Main Content


Medical emergency when bronchospasm is refractory to bronchodilator and steroids in the ED.


High-risk predictors:


  • Previous severe exacerbation (e.g., intubation or ICU admission for asthma)
  • Two or more hospitalizations for asthma in the past year
  • Three or more ED visits for asthma in the past year
  • Hospitalization or ED visit for asthma in the past month
  • Using >2 canisters of short-acting beta-2-agonist per month
  • Attack while under systemic steroids, or recent discontinuation of steroids
  • Difficulty perceiving asthma symptoms or severity of exacerbations, noncompliance

Table Graphic Jump Location
Table 205-1 Special Considerations for Anesthesia

Signs of severity:


  • Cyanosis, profuse sweating, mental status changes
  • Bradycardia, hypotension, pulsus paradoxus >15 mm Hg
  • Accessory muscle use, silent chest, difficulty speaking, inability to lie down
  • Peak expiratory flow rate (PEFR) <200 L/min and/or <40% predicted/usual value
  • FEV1 <40% of predicted is an ominous sign in an adult
  • Room air SpO2 <92%, PaO2 <60 mm Hg, Paco2 >45 mm Hg


See Table 205-2 for drug dosages.


  • Oxygen: keep SaO2 ≥92% (>95% in pregnancy)
  • Inhaled nebulized beta-2-agonist: albuterol
  • Inhaled nebulized anticholinergic agent: ipratropium bromide, along with albuterol
  • Steroids: methylprednisolone, dexamethasone, or hydrocortisone, IV, IM, or even PO:
    • Give steroids early as peak action delayed by 3–4 hours
  • Monitor K; replete as needed: both beta-agonists and steroids cause hypokalemia
  • If high-risk predictors, signs of severity, no improvement after first treatment, transfer to ICU
  • Magnesium sulfate IV if no resolution after 1 hour of continuous nebulization and steroids, or as first line if signs of severity
  • Terbutaline or epinephrine (never both) after 1 hour of nebulization and steroids
  • Heliox-driven albuterol nebulization after 1 hour of continuous nebulization and steroids. It decreases work of breathing and improve ventilation (but may lower O2)
  • Ketamine is sometimes helpful when everything else fails before intubation
  • Intubate with rapid sequence if:
    • Lethargic
    • Unable to maintain airway
    • Slow respiratory rate
    • PCO2 normal or high
  • If intubated:
    • Vt 5–7 mL/kg, RR 6–8/min, I:E 1:3 ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.


About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessAnesthesiology Full Site: One-Year Subscription

Connect to the full suite of AccessAnesthesiology content and resources including procedural videos, interactive self-assessment, real-life cases, 20+ textbooks, and more

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessAnesthesiology

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.