Croup is a clinical syndrome of upper airway obstruction defined by barking cough, stridor, and hoarseness. Management hinges on severity assessment, universal corticosteroid use, and selective epinephrine. The key clinical task is distinguishing typical croup from high-risk mimics that require urgent airway intervention.

Learning Objectives

1. Differentiate croup from other causes of pediatric upper airway obstruction using key historical and physical exam features.


2. Apply a severity-based approach to croup management, including appropriate use of corticosteroids and nebulized epinephrine.


3. Recognize clinical features that suggest alternative or life-threatening diagnoses requiring escalation of care.

References

1. Cooke A, Conway S, Griffin L. Croup: Rapid Evidence Review. Am Fam Physician. 2026;113(3):254-258.


2. Gates A, Johnson DW, Klassen TP. Glucocorticoids for Croup in Children. JAMA Pediatr. 2019;173(6):595-596. doi:10.1001/jamapediatrics.2019.0834


3. Bjornson CL, Klassen TP, Williamson J, et al. A Randomized Trial of a Single Dose of Oral Dexamethasone for Mild Croup. N Engl J Med. 2004;351(13):1306-1313. doi:10.1056/NEJMoa033534


4. Bjornson CL, Johnson DW. Croup. Lancet. 2008;371(9609):329-339. doi:10.1016/S0140-6736(08)60170-1


5. Bjornson C, Russell K, Vandermeer B, Klassen TP, Johnson DW. Nebulized Epinephrine for Croup in Children. Cochrane Database Syst Rev. 2013;(10):CD006619. doi:10.1002/14651858.CD006619.pub3

Transcript

This transcript was generated using Descript and subsequently reviewed and lightly edited for spelling, grammar, and clarity. Minor inaccuracies may remain, and the audio recording should be considered the definitive version of this content.

 Welcome to PEM Currents: The Pediatric Emergency Medicine Podcast. As always, I’m your host, Brad Sobolewski. And today we’re gonna talk about croup. We’re gonna focus on diagnosis, severity based management, and how to differentiate it from scarier high risk conditions that may present similarly, but behave very differently.

So croup is best understood as a clinical syndrome of upper airway obstruction caused by inflammation at the level of the larynx and subglottis. So in most cases this is viral laryngotracheitis, most commonly due to parainfluenza virus. But as you’d expect multiple viruses can cause it. The subglottis is the narrowest portion of the pediatric airway.

So even small amounts of edema create large increases in airway resistance. So that’s why the clinical picture is so consistent. You’ve got inspiratory stridor, hoarseness, and that characteristic barking cough, which either sounds like a seal or a dog, and yes, of course, I know the difference between the two coughs because I was a biology major.

This is primarily a disease of children between six months and three years of age with a peak incidence in the second year of life. It’s really, really common, like one and a half percent of all ED visits, maybe 350,000 visits a year, and 85% of these kids have mild disease. Hospitalization is rare. The range is variable, about two to 8% of cases, and return visits occur in about three to 5%. Fewer than 1% of children, a lot fewer, require intensive care or airway intervention. Honestly, most kids do really well. The ones who don’t can get sick very quickly, and that’s been my clinical experience.

In the Northern Hemisphere, we see croup throughout the fall and winter, usually starting in around November and sort of tapering off by April. But that being said, I’ve seen croup-like symptoms every month of the year over the past couple of decades.

Croup is absolutely a classic clinical diagnosis. A typical case begins with 12 to 48 hours of viral prodrome, you know, body aches, fever, congestion, cough, followed by often abrupt nighttime onset of barky cough and stridor. Symptoms fluctuate, and they’re generally worse with agitation and get better when the kid is calm. That variability is the key feature.

So what you’ll have is a child who wakes up after sleeping for a few hours with a barky cough and then noisy stridor. This freaks parents out, and this is not hyperbole. There’s this little center in the back of your brain that’s like, please don’t stop breathing and die. So appropriately, they’re worried about the kid, they call emergency medical services, they bring them to the emergency department, and by and large, by the time they get there, the stridor has resolved. The kid is calm, and parents will say, I swear he looked a lot worse at home. Trust me, we believe you parents, this is what croup does.

When I’m taking a history of croup, I get all of these details. Are there any sick contacts? If the parents are worried about a foreign body inhalation or ingestion, then I’m worried about a foreign body inhalation or ingestion. Listen to the lungs, inspect their airway. Always check the ears for concomitant otitis and I’ll feel their trachea. I’ll actually grab and hold the trachea and move it. Kids with croup really don’t have a painful trachea. Kids with bacterial tracheitis, aside from looking more toxic, actually have a lot of pain when they move their trachea.

Testing for croup is generally unnecessary. Labs and viral studies do not change management, and imaging is really reserved for atypical presentations or when you’re considering an alternative diagnosis like a foreign body. If you do get an X-ray, what you’re looking for is the classic steeple sign on the AP view. It is seen in croup, but it’s not 100% sensitive nor specific.

Once you’ve made the diagnosis of croup, it’s important to assess severity, and remember that I said that most kids are mild. So mild croup is defined by the absence of stridor at rest. So they may have some stridor when they’re upset or even a little bit of hoarseness or noise. It’s important to listen to many, many children with croup to get a sense of this.

Moderate croup includes stridor at rest with mild to moderate retractions. So at rest means that the child is in a position of comfort. They’re calm with a parent, and they’ve generally been that way for about 10 to 15 minutes. Sometimes that’s how long it can take for the stridor to dissipate once you get the kid calm.

Severe croup, which is fortunately rare, involves marked work of breathing, agitation, fatigue, need for oxygen, altered mental status, and this aligns with the Westley croup score. It formalizes stridor, retractions, air entry, cyanosis, and mental status. But really, in practice, most of us get very good at bedside assessment of croup.

Management of croup starts with corticosteroids. This is one of the highest-yield interventions that we have in pediatric emergency medicine. Every child with croup should receive dexamethasone. Typically 0.6 milligram per kilogram as a single dose up to a maximum of 10 milligrams. Some places will use 0.15 milligram per kilogram.

Locally, we often give the IV formulation orally. It’s 10 milligrams per mL. Tastes bad, but pairs reasonably well with apple juice. The oral suspension is 1 milligram per mL, tastes terrible, and pairs nicely with being spit on the ground by toddlers.

The evidence behind dexamethasone is very robust. The main benefit is that it reduces return visits and hospital readmissions by about half, and those return visits include doctor’s offices and emergency departments. In a Cochrane review of 1,679 children, glucocorticoids reduce return visits or readmissions with a risk ratio of 0.52, so that translates to a number needed to treat of seven.

I’ve certainly seen seven or more croup kids during one shift, so for every seven children treated with dexamethasone, one return visit is prevented. Symptom improvement begins within about two hours and lasts at least 24 hours, but maybe up to a couple of days. Hospital length of stay for kids that get steroids is reduced by an average of 15 hours as well. Serious adverse events are rare. It’s well tolerated, and other than the taste, kids do fine with it. And importantly, the benefit is consistent across all severities of croup, mild, moderate, and severe.

So when you explain this to families who are very scared about their kids, but now their kid is looking better and you’re only giving them a single medicine, not doing any tests or X-rays or anything, I think you have to frame the medicine in terms of what it’s going to do for them over the next couple of days.

So one way of explaining this to families would be to say something like this is a steroid called dexamethasone. It reduces the swelling in your child’s airway that’s causing the barky cough and noisy breathing. Most children start feeling better within a couple of hours, and the benefit lasts at least a full day, if not longer.

Without this medicine, about one in five children need to come back because symptoms get worse again. You really get two bad days with croup in most cases. With this medicine, the risk of returning drops to about one in 10, so it cuts the chance of coming back in half.

We can expect your child’s cough to start improving over the next day or two. Most children are feeling a lot better within 48 hours, though a little bit of hoarseness and cough can last for a week to about 10 days.

So it’s possible that when your child goes to sleep later tonight, they may experience that barking cough and noisy breathing again. They’re almost certainly going to be upset. The steroid blunts enough of the swelling so that you are much more likely to hav