It’s 2230 and Roberto, 2, is sitting in triage when, from across the department you hear a seal-bark cough. He becomes distressed and is quickly bundled into the resus bay by the worried triage staff. You hear a biphasic stridor and can see some intercostal recession. Roberto’s parents are worried and tearful.
- Croup is viral laryngotracheitis
- Consider the “Big Four” Differentials
- Keep everyone calm
- Assess the severity
- Give steroids early
- Think critically about your management
Croup is also known as laryngotracheitis. It’s an inflamed larynx and trachea, secondary to viral infection. It can occasionally progress to laryngotracheobronchitis; involving the bronchi.
Croup is most prevalent in the 6–36 month age group, and boys are affected more often than girls. A positive family history is associated with a four-fold likelihood of having croup.
According to a US study, only 1 in 20 require admission to hospital (re-presentation rate ~1 in 20 of DEM discharges within 48hrs).
The most common cause of croup is Parainfluenza virus type 1 (PIV1), which peaks in infection rates every two years. Judging from the increased number of presentations so far this autumn, here in Australia, it’s a “croup year”. Sporadic cases of croup are often due to PIV3, which reportedly can be more severe.
- Tracheal narrowing at sub-glottic level
- Fixed obstruction
- Dynamic obstruction
The clinical presentation of croup has some hallmark features:
Additionally, you may identify:
- Presentation to hospital in the evening and at night
- Gradual onset 12-48 hrs
Features that are not consistent with croup:
- Toxic looking child
- Posturing to protect airway
- Sore throat
If you remember nothing else from this post, it’s to consider the differential diagnoses for croup. The big four:
- Acute epiglottitis
- Bacterial tracheitis
- Foreign body, inhaled or aspirated
- Allergic reaction / anaphylaxis
These can be life threatening. Consider them in every patient who is stridulous or has a barking cough.
- Peritonsillar & retropharyngeal abscess
- Upper airway injury
- Congenital upper airway anomalies
- Acute angioneurotic oedema
- Neck mass
- Laryngeal diphtheria
There are a few different scoring systems to ascertain the severity of croup. The Westley croup score was first described in 1978 for a trial comparing nebulized adrenaline vs saline for croup. The scoring system, shown below, heavily weights more ominous signs, and is more for the purpose of research than clinical usage.
Keep the child calm.
Keep the parents calm.
Mild / Moderate:
PO Dexamethasone or PO Prednisolone.
A period of observation.
Adrenaline, nebulised (5mL of 1:1000)
IM/IV Dexamethasone 0.6mg/kg (max 12mg)
Admit & observe
The management of croup is an ongoing debates in Paediatrics, with strong opinions. We’d love you to comment below to voice your thoughts on each of these…
Adrenaline: It’s a no-brainer to use adrenaline in severe croup. The controversy is around the a) a threshold for nebulized adrenaline and, b) the use of multiple doses of nebulized adrenaline.
The 2013 Cochrane Review states:
“Compared to no medication, inhaled epinephrine improved croup symptoms in children at 30 minutes following treatment (three studies, 94 children). This treatment effect disappeared two hours after treatment (one study, 20 children). However, children’s symptoms did not become worse than prior to treatment. No study measured adverse events.”
Indeed, Westley’s 1978 study had similar findings to this much more recent review.
Anecdotally, we tend to see a fair amount of adrenaline overuse, in lieu of keeping the child calm. Indeed, nebulised adrenaline can have the opposite effect; putting something on the child’s face, wrestling with them and giving the child a tachycardia (distress, not adrenaline). The ‘need’ for this treatment can also convey an overly worried demeanor to child & parents, further distressing everyone.
Steroids: Oral dexamethasone (and the dosage) vs oral prednisolone has been the topic of a number of studies in the last two decades, with regular publications in favour of either. Check your local guidelines and preferences, and give the steroids early. For what it’s worth, I lean towards dexamethasone – it’s longer acting and may just reduce the inflammation enough to account for a second night of symptoms. Again, we’d love you to comment below.
Croup is NOT a benign self limiting illness. It’s an illness that is usually benign and self limiting but can very definitely kill you.
Once the initial airway compromise is managed with steroids, further sequelae are very rare.
Nonetheless, ~3 in 1000 cases require intubation, with
<0.5% mortality in intubated patients.
Kids should never be discharged with a stridor at rest!
Roberto settles down for the night in short stay, and can be hear breathing quietly when you check him through the night. He goes home after tucking into a large breakfast.
Cronin et al. Single dose oral dexamethasone versus multi-dose prednisolone in the treatment of acute exacerbations of asthma in children who attend the emergency department: study protocol for a randomized controlled trial. Trials 2012, 13:141
Bjornson C et al., Nebulised epinephrine for croup in children (Review), 2013. Cochrane Collaboration