The Art and Algorithm of Croup, Part 2: Scoring the Severity [+ Editor’s Commentary + Croup Starter Kit]

Be sure to check out Part 1: Music To My Ears…Or Is it?

When it comes to croup, the clinical nuance lies in recognizing severity: stridor at rest, retractions, agitation, hypoxia, and fatigue. All children with croup should receive a steroid, namely oral dexamethasone. Treat seven to thirteen children with a single dose of dexamethasone, and you prevent one from coming back to the ED – pretty solid odds for a small intervention.

But the real decision points come next: consider whether racemic epinephrine is needed and how long the child should be observed in the ED post-therapy. The Westley Croup Score can help quantify disease severity, but at the bedside I tend to triage and think about next steps this way:

Mild: Barking cough, no stridor at rest, not hypoxemic → Dex → discharge home with strict return precautions

Moderate: Barking cough + stridor at rest, not hypoxemic → Dex + rac epi + observe 2 hours, if no stridor at rest, no/minimal retractions → discharge home with strict return precautions

Severe: Barking cough + stridor at rest + retractions → Dex + rac epi + observe

So you’ve given dex and your first dose of racemic epinephrine – now what? The child is still having stridor at rest, maybe hypoxemic, maybe retracting…or all of the above. How quickly should you reassess for rebound symptoms? Should I order another round of rac epi? Now? When? How long should you keep them under observation in the ED?

Let’s pause on the questions for a second and focus on the medications in our croup orchestra: racemic epinephrine and dexamethasone. Here’s what you need to know to use them safely and effectively, and what to do if that first dose doesn’t fully hit the right notes.

Let’s Talk About Rac Epi (Let’s Talk About You and Me)

Mechanism: Rapid vasoconstriction of airway mucosa – think of it as turning down the swelling so airflow can hit the right notes.
Onset & Duration: Kicks in within 10-30 minutes, lasts 1-2 hours, with a half-life of about 4 hours.
Dose: 0.25 mL for children <5 kg, 0.5 mL for those >5 kg.

I’m all About That Dex (No Treble)

When to use it: All kids with croup, no matter the severity.
Why it matters: Dexamethasone decreases symptom severity for up to 24 hours, shortens ED observation time, and lowers admission rates.
Onset: 30 minutes to 6 hours (so sometimes you’re waiting for the orchestra to really warm up).
Dose: Standard is 0.6 mg/kg, usually capped at 10–16 mg, given orally, IM, or IV. (Editor’s Note: The dose of PO dex is institutional dependent, and the evidence suggests that doses as low as 0.15 mg/kg may be effective. The CHOP pathway uses 0.3 mg/kg, but some places go up to 0.6 mg/kg. ~JB)

The “Observation Gap”

Here’s where timing gets tricky. Epinephrine wears off in 1–2 hours, while steroids can take up to 6 hours to reach full effect. Historically, we worried about a “rebound” of symptoms after the epinephrine faded. Current evidence suggests:

• Optimal observation: 2–4 hours post-epinephrine reduces treatment failure (defined as needing a second dose or returning to the ED within 24 hours).
• Bridging the gap: A second epinephrine dose (for those with continued stridor at rest) can help tide a child over until the steroid kicks in.
  

Multidose Epinephrine: When the Soloist Needs a Encore

• Kids who need multiple doses are admitted more often (70.5% vs. 10.7% for a single dose).
• Interestingly, some kids who get multiple doses and are discharged are less likely to return within a week compared to single-dose patients (0.8% vs. 5.4%).
• Takeaway: For selected stable patients, multidose epinephrine can work safely as an outpatient strategy – but you still have to watch the orchestra carefully.
  

Deciding on Discharge vs. Admission

Safe Discharge:

• No stridor at rest, no tachypnea, no increased work of breathing.
• Adequate aeration and receipt of dexamethasone.
• Observation of 2–4 hours post-epinephrine with no new respiratory symptoms.
• No other social or medical reasons to admit.
  

Admission:

• Severe disease at presentation or lack of improvement.
• Two or more doses of racemic epinephrine needed for persistent/rebound symptoms.
• Young age (<6 months) or uncertain diagnosis.
  

Advanced/Non-Standard Therapies

• Heliox: Can reduce airflow turbulence but is not standard.
• BiPAP: Occasionally used, but not part of routine management.
  

Bottom Line: Watch the child, manage inflammation, and know the right tempo for intervention. With steroids on deck and racemic epinephrine hitting the high notes, most kids can return home safely once the airway is stable.

Editor’s Note: Thanks to Katheryn for this great overview on croup. While the treatment of croup (Dex +/- Racemic epi) is pretty straightforward, there are still some controversies/differences that are institution-dependent. The 2 rac epi then admit approach is one of them; one study showed that about a fifth of admitted croup patients need “significant intervention” – sounds worrisome, I know. But….the vast majority of these interventions were additional racemic epinephrine doses – and very few required escalation to the ICU. With this knowledge, and acknowledging the burden for families who need to be admitted to the hospital, I think there is more of a trend to consider “resetting the clock” after the 2nd dose of racemic epinephrine. I tend to watch for a few more hours (maybe 2-3 hours) after that second dose; if they sustain improvement, it’s likely the steroids are starting to kick in at that point, and they will probably fly at home.

Another interesting thought posed by Dr. Bryan Stocker on Katheryn’s last post: “If we know that stridor is just turbulent flow, and we know from Poiseuille’s law that a small amount of radius change can cause turbulence, why should we care about stridor at rest with no labored breathing?“ It’s a valid point – we know that croup causes swelling in the airway, but shouldn’t we care more about their work of breathing? I welcome others to post their perspectives in the comment section below, but I would say often times in my experience, stridor at rest and increased work of breathing go hand in hand. When a child has mild stridor at rest but looks comfortable, I tend to observe them for longer in the ED – they often will present themselves one way or another, and make it clear whether they need escalation of care or are safe for discharge. Where this also plays a part is in my anticipatory guidance for families. I advise them that they usually should return to the ED for stridor at rest or increased work of breathing, and I reinforce that if they see one, they’ll likely see the other. If they start to hear stridor but the patient looks comfortable, I advise that those are the times they can triage and initiate home interventions: cold exposure from outdoors or the freezer, steam from the shower. If it improves the stridor, probably fine to continue keeping an eye on things at home. If the stridor persists, it’s often time to come back to the ED. ~JB

Want to brush up on the evidence for croup? Here’s your Croup Start Pack:

Overview: CHOP Clinical Pathway: Croup

Treatment: Outdoor Cold Air Versus Room Temperature Exposure for Croup Symptoms: A Randomized Controlled Trial

Treatment: Cochrane Review: Glucocorticoids for croup in children

Treatment: 27 years of croup: an update highlighting the effectiveness of 0.15 mg/kg of dexamethasone

Treatment: Cochrane Review: Nebulized epinephrine for croup in children

Treatment: Cochrane Review: Heliox for croup in children

Disposition: Hospital Course of Croup After Emergency Department Management

FOAM, Blog: PEMBlog – How to Find a Quality Blog Post on Croup: Findings from a SOAR Review

FOAM, Blog: Core EM – Croup

FOAM, Blog: DFTB – Croup

FOAM, Blog: DFTB – Corticosteroids for Croup

FOAM, Blog: Pediatric EM Morsels – Recurrent Croup

FOAM, Podcast: PEM Currents – Croup

FOAM, Podcast: Core EM Podcast – Croup

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