title: Humidified air inhalation for treating croup: a systematic review and meta-analysis.
abstract: BACKGROUND
  Croup (laryngotracheobronchitis) is a common cause of upper airway obstruction in children. Treatment with humidified air was previously widely used and is still commonly recommended as home treatment.
  
  
  OBJECTIVE
  To assess the efficacy of humidified air in the treatment of croup.
  
  
  METHODS
  Systematic review and meta-analysis.
  
  
  METHODS
  We searched the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE.
  
  
  METHODS
  We included randomized controlled trials with or without blinding. All studies treating children with a clinical diagnosis of croup with warm or cool humidified air delivered by steam or humidified tent whether inpatients, attenders at the Emergency Department or in the community were eligible.
  
  
  RESULTS
  Three studies in emergency settings provided data on 135 patients with moderate croup for the main outcome (croup score). The combined results from 20 to 60 minutes in the three studies marginally favoured the treatment group with a weighted standardized mean difference of -0.14 (95% confidence interval = -0.75 to 0.47). No outcomes were significantly different between the groups.
  
  
  CONCLUSIONS
  The croup score of children managed in an emergency setting with mild to moderate croup probably does not improve greatly with inhalation of humidified air. There is insufficient evidence to exclude either a small beneficial or a harmful effect.
authors.affiliation: Three Swans Surgery, Rollestone Street, Salisbury SP1 1DX, UK. mvm198@soton.ac.uk
authors.forename: Michael
authors.initials: M
authors.lastname: Moore
authors.forename: Paul
authors.initials: P
authors.lastname: Little
mesh_terms: D002675:Child, Preschool; D003440:Croup / Q000503:physiopathology / Q000628:therapy*; D004635:Emergency Medicine; D006801:Humans; D006813:Humidity; D007223:Infant; D010372:Pediatrics; D012138:Respiratory Therapy; D006113:United Kingdom