Treatment

Children with croup should be made comfortable and care should be taken to avoid agitating the child, such as using a non-contact form of oxygen delivery e.g. allowing the child’s care-giver to deliver oxygen using a ‘wafting’ technique. Oxygen should be administered to any child with oxygen saturation <92% on air.

In the 19th century steam and mist therapy were used. There is no published evidence to support its use and small trials failed to show an improvement in oxygen saturations, respiratory rate, heart rate or croup score. In addition, there have been cases reported of scald injuries in children treated with hot humidified air. [11-13]

The aetiology of croup is viral and therefore antibiotics are not indicated. Bacterial tracheitis and pneumonia following croup are rare; occurring in less than one in a thousand cases.

Nebulised adrenaline

Nebulised adrenaline is only used in children with severe and life-threatening croup.

Treatment is with 0.5 mL/kg of 1:1,000 concentration to a maximum dose of 5 mL.

Double blind randomised control trials of this treatment demonstrate an improvement within 30 minutes and last up to 2 hours. As the effect wears off, the child’s symptoms return to base line level, however, a proportion of children deteriorate even further. [7,14,15]

However, Adrenaline does allow time for an experienced team including a senior anaesthetist to be gathered as well as rapidly improving the patient’s distress.

The benefit of using corticosteroids

There are numerous well-designed trials and reviews that clearly demonstrate clinical benefit of corticosteroids irrespective of severity. In children with severe or impending respiratory failure, there is an absolute risk reduction of 1.1% in the rate of intubation. [16]

Oral dexamethasone

Oral dexamethasone 0.15 mg/kg has been shown to be superior to prednisolone at a dose of 1 mg/kg. An equivalence trial demonstrated a re-presentation rate of 29% in the prednisolone group compared to 7% in the dexamethasone group. [17]

There is no difference in efficacy between oral and intramuscular dexamethasone.

If the child is vomiting, 2 mg of nebulised budesonide can be used. However, nebulised budesonide can agitate the child whilst being delivered and taking into account the cost of equipment required as well as budesonide being more expensive, dexamethasone is the preferred treatment. [17-20]

Trial data

A meta-analysis of trials demonstrated a reduction in the croup score of three points by six hours in those treated with dexamethasone and by one point in those treated with budesonide.

There was also a reduction in the number of children requiring rescue treatment with nebulised adrenaline of 9% and 12% in those treated with budesonide and dexamethasone respectively.

In addition, the length of time spent in the emergency department (ED) was reduced as was the admission rate in those treated with dexamethasone or budesonide. [21]

Oral dexamethasone dose

The Cochrane review [22] concluded that a dose of dexamethasone of 0.15 mg/kg compared to 0.6 mg/kg did not find any important difference between croup scores at 2, 6 or 12 hours, return visits or (re)admission of children, length of stay in the hospital.

Local protocols should be followed for dosing.

Learning bite

• The mainstay of treatment for croup is corticosteroids, which take between 2 and 4 hours to have a clinical effect.