The Effects of Pressurized Isoproterenol and Salbutamol in Asthmatic Children

Abstract

The effects of inhaling 250µg of isoproterenol, 200µg of salbutamol, or water mist were studied in 58 asthmatic children. While a highly significant increase in mean FEV1 occurred after both medications, several individual cases failed to respond: a poor response was most often seen in those with a low initial FEV1. After isoproterenol there was a significant correlation between FEV1 and increase in heart rate, and a highly significant correlation between increase in FEV1 and a fall in Po2. No significant change in heart rate or in Po2 occurred after either salbutamol or water. It is concluded, first, that both bronchodilator aerosols in recommended dose are effective in some cases of asthma but not in others, particularly severe ones; secondly, if a patient is able to inhale a full recommended dose of isoproterenol tachycardia is likely to result; and thirdly that a fall in blood oxygen tension may be expected if isoproterenol-induced bronchodilatation occurs.