Nebulized albuterol delivery is associated with decreased skeletal muscle strength in comparison with metered-dose inhaler delivery among children with acute asthma exacerbations

Objective Albuterol is a beta 2-agonist and causes an intracellular shift of potassium from the interstitium. Whole-body hypokalemia is known to cause skeletal muscle weakness, but whether this occurs as a result of hypokalemia from the intracellular shift during albuterol treatment is unknown. We sought to determine if albuterol total dose or route of administration (nebulization and/or metered-dose inhaler) is associated with skeletal muscle weakness. Methods This was a prospective observational study using convenience sampling. Skeletal muscle strength was measured before and after 1 hour of albuterol treatment using a hand-grip dynamometer in participants aged 5-17 years with acute asthma exacerbation in the emergency department. We examined associations of albuterol dose and route of administration with changes in grip strength. Results Among 50 participants, 10 received continuous albuterol by nebulizer and 40 received albuterol by metered-dose inhaler. The median (interquartile range) in change of grip was -7.8% (interquartile range, -23.3, +5.1) for those treated with a nebulizer and +2.4% (interquartile range, -5%, +12.7%) for those treated with a metered-dose inhaler (P = 0.036 for the difference). In a multiple linear regression model adjusted for the pretreatment Acute Asthma Intensity Research Score and age, participants treated with a nebulizer had a 12.9% decrease in skeletal muscle strength compared with those treated with a metered-dose inhaler. Conclusion Higher doses of albuterol administered via nebulization result in decreased skeletal muscle strength in patients with acute asthma; whereas, albuterol administration via metered-dose inhalers showed no effect on skeletal muscle strength.