Heliox in children with croup: a strategy to hasten improvement.

Objective: Upper airway obstruction is responsive to the reduction in airflow turbulence provided by helium/oxygen (heliox) admixture. Our pediatric critical care transport team (PCCTT) has used heliox for children with upper airway obstruction from croup. We sought to describe our experience with heliox on transport and hypothesized that heliox-treated children with croup would show a more rapid clinical improvement.

Methods: Children with croup transported by our PCCTT and admitted to the PICU were evaluated. We analyzed pretransport care, transport interventions, and outcomes. Croup scores (Modified Taussig) were assigned retrospectively according to respiratory therapy charting. Data were analyzed using appropriate statistical tests, including Pearson's chi-square test, Fisher's exact test, Mann-Whitney U rank comparison, and two-sample t-test.

Results: Thirty-five children met inclusion criteria. Demographics were similar between groups. The pretransport medical care was similar between groups. Children receiving heliox had a higher baseline croup score [mean (SD) = 5.7(2.3) vs no heliox 2.9 (2.0), P < 0.001]. The improvement in croup scores over the first 60 minutes of transport was more rapid in the heliox-treated children (P < 0.001). There was no difference in the number of children requiring additional nebulized racemic epinephrine during transport. The PICU length of stay (P = 0.59) and hospital length of stay (P = 0.64) were similar between groups.

Conclusion: Heliox added to standard transport treatment for critically ill children with croup provides a more rapid improvement in croup scores. Heliox for croup during transport does not prolong intensive care unit stay. A prospective clinical trial is warranted to evaluate heliox in pediatric transport.