Intravenous salbutamol bolus compared with an aminophylline infusion in children with severe asthma: a randomised controlled trial

Background: The relative efficacies of aminophylline and salbutamol in severe acute childhood asthma are currently unclear. A single bolus of salbutamol was compared with a continuous aminophylline infusion in children with severe asthma in a randomised double blind study. Methods: Children aged 1–16 years with acute severe asthma were enrolled if they showed little improvement with three nebulisers (combined salbutamol and ipratropium) administered over an hour and systemic steroids. Subjects were randomised to receive either a short intravenous bolus of salbutamol (15 μg/kg over 20 minutes) followed by a saline infusion or an aminophylline infusion (5 mg/kg over 20 minutes) followed by 0.9 mg/kg/h. Results: Forty four subjects were enrolled, with 18 randomly allocated to receive salbutamol and 26 to receive aminophylline. The groups were well matched at baseline. An intention to treat analysis showed that there was no statistically significant difference in the asthma severity score (ASS) at 2 hours between the two groups (median (IQR) 6 (6, 8) and 6.5 (5, 8) for salbutamol and aminophylline respectively, p=0.93). A similar improvement in ASS to 2 hours was seen in the two groups (mean difference –0.08, 95% CI –0.97 to 0.80), there was a trend (p=0.07) towards a longer duration of oxygen therapy in the salbutamol group (17.8 hours (95% CI 8.5 to 37.5) v 7.0 hours (95% CI 3.4 to 14.2)), and a significantly (p=0.02) longer length of hospital stay in the salbutamol group (85.4 (95% CI 66.1 to 110.2) hours v 57.3 hours (95% CI 45.6 to 72.0)). There was no significant difference in adverse events between the two groups. Conclusions: This study suggests that, in severe childhood asthma, there is no significant difference in the effectiveness of a bolus of salbutamol and an aminophylline infusion in the first 2 hours of treatment. Overall, the aminophylline infusion was superior as it significantly reduced the length of stay in hospital.