Low-dose l-isoproterenol versus salbutamol in hospitalized pediatric patients with severe acute exacerbation of asthma : A double-blind, randomized controlled trial

• Published in: Allergology International Vol. 68; no. 3; pp. 335 - 341
• Main Authors: Toshio Katsunumaa, Takao Fujisawab, Takanobu Maekawac, Kenichi Akashid, Yukihiro Ohyae, Yuichi Adachif, Koji Hashimotog, Mihoko Mizunoh, Takanori Imaii, Mari S. Obaj, Mayumi Sakok, Yasuo Ohashil, Hidefumi Nakamuram
• Format: Journal Article
• Language: Japanese
• Published: JAPANESE SOCIETY OF ALLERGOLOGY 01-07-2019
• ISSN: 1323-8930

[ABSTRACT] Background: Although the guidelines in most countries do not recommend continuous inhalation of l-isoproterenol to treat pediatric patients with acute severe exacerbation of asthma, lower dose of l-isoproterenol has been widely used in Japan. To determine whether the efficacy of low-dose l-isoproterenol was superior to that of salbutamol, we conducted a double-blind, randomized controlled trial. Methods: Hospitalized patients aged 1-17 years were eligible if they had severe asthma exacerbation defined by the modified pulmonary index score (MPIS). Patients were randomly assigned (1:1) to receive inhalation of l-isoproterenol (10 μg/kg/h) or salbutamol (500 μg/kg/h) for 12 hours via a large-volume nebulizer with oxygen. The primary outcome was the change in MPIS from baseline to 3 hours after starting inhalation. Trial registration number UMIN000001991. Results: From December 2009 to October 2013, 83 patients (42 in the l-isoproterenol group and 41 in the salbutamol group) were enrolled into the study. Of these, one patient in the l-isoproterenol group did not receive the study drug and was excluded from the analysis. Compared with salbutamol, l-isoproterenol reduced MPIS more rapidly. Mean (SD) changes in MPIS at 3 hours were -2.9 (2.5) in the l-isoproterenol group and -0.9 (2.3) in the salbutamol group (difference -2.0, 95% confidence interval -3.1 to -0.9; P<0.001). Adverse events occurred in 1 (2%) and 11 (27%) patients in the l-isoproterenol and salbutamol groups, respectively (P=0.003). Hypokalemia and tachycardia occurred only in the salbutamol group. Conclusions: Low-dose l-isoproterenol has a more rapid effect with fewer adverse events than salbutamol.