Croup.

INTRODUCTION: Croup leads to signs of upper airway obstruction, and must be differentiated from acute epiglottitis, bacterial tracheitis, or an inhaled foreign body. Croup affects about 3% of children a year, usually between the ages of 6 months and 3 years, and 75% of infections are caused by Parainfluenza virus. Symptoms usually resolve within 48 hours, but severe infection can, rarely, lead to pneumonia, and to respiratory failure and arrest.

METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments in children with: mild croup; moderate to severe croup; and impending respiratory failure because of severe croup? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2008 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS: We found 43 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS: In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics, corticosteroids, dexamethasone (intramuscular, oral, single-dose oral, route of administration), heliox, humidification, intermittent positive pressure breathing, L-adrenaline, nebulised adrenaline (epinephrine), nebulised budesonide, nebulised short-acting beta(2) agonists, oral decongestants, oral prednisolone, oxygen, and sedatives.