Although most children with the condition suffer a mild and self-limited illness of short duration, the stress and disruption experienced by the child and family are well documented.[100]Johnson D, Williamson J. Croup: duration of symptoms and impact on family functioning. Pediatr Res. 2001;49:83A.
Mild
Self-limited without treatment but shorter time to resolution with dexamethasone treatment.
Moderate
Reasonable outlook. While symptoms of obstruction may be frightening, symptoms resolve without significant complications.
Severe
Before corticosteroids became standard treatment, children with severe croup were 5 times more likely to receive endotracheal intubation,[57]Kairys SW, Marsh-Olmstead EM, O'Connor GT. Steroid treatment of laryngotracheitis: a meta-analysis of the evidence from randomized trials. Pediatrics. 1989 May;83(5):683-93.
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and remained intubated for 30% longer.[52]Tibballs J, Shann FA, Landau LI. Placebo-controlled trial of prednisolone in children intubated for croup. Lancet. 1992 Sep 26;340(8822):745-8.
http://www.ncbi.nlm.nih.gov/pubmed/1356176?tool=bestpractice.com
Introduction of routine corticosteroid treatment has dramatically decreased numbers of children intubated, reduced number of days spent in ICU, and shortened length of hospital stay.[55]Geelhoed GC. Sixteen years of croup in a Western Australian teaching hospital: effects of routine steroid treatment. Ann Emerg Med. 1996 Dec;28(6):621-6.
http://www.ncbi.nlm.nih.gov/pubmed/8953950?tool=bestpractice.com
Since combination treatment with dexamethasone and nebulised epinephrine (adrenaline) became standard care, prognosis for severe croup has been excellent.
Impending respiratory failure
Very rare, with intubation required in only 1% to 3% of all cases.[48]Sofer S, Dagan R, Tal A. The need for intubation in serious upper respiratory tract infection in pediatric patients (a retrospective study). Infection. 1991 May-Jun;19(3):131-4.
http://www.ncbi.nlm.nih.gov/pubmed/1889864?tool=bestpractice.com
[49]Sendi K, Crysdale WS, Yoo J. Tracheitis: outcome of 1,700 cases presenting to the emergency department during two years. J Otolaryngol. 1992 Feb;21(1):20-4.
http://www.ncbi.nlm.nih.gov/pubmed/1564745?tool=bestpractice.com
[50]Tan AK, Manoukian JJ. Hospitalized croup (bacterial and viral): the role of rigid endoscopy. J Otolaryngol. 1992 Feb;21(1):48-53.
http://www.ncbi.nlm.nih.gov/pubmed/1564750?tool=bestpractice.com
[51]Dawson KP, Mogridge N, Downward G. Severe acute laryngotracheitis in Christchurch 1980-90. N Z Med J. 1991 Sep 11;104(919):374-5.
http://www.ncbi.nlm.nih.gov/pubmed/1923075?tool=bestpractice.com