Objective To evaluate the effectiveness of a helium oxygen mixture (79%He 21%O 2) as an aerosolizing compressed gas for β 2 agonist therapy in patients with an asthma exacerbation Methods Twenty four patients in the outpatient department with a mild to moderate exacerbation of asthma were enrolled The patients were randomly divided into an experimental group (13 cases) and a control group (11 cases) The experimental group inhaled Berotec with heliox driven, and the control group inhaled Berotec with compressed air driven Eight hospitalized patients in the respiratory department with severe exacerbation of asthma were enrolled The patients inhaled Berotec with heliox driven or compressed air driven in a random order Results The results of spirometric parameters and arterial blood gas analysis were measured In the mild to moderate asthma patients, no statistical differences between the two groups for forced vital capacity (FVC), forced expired volume in one second (FEV 1), and expiratory flow in 50% forced vital capacity (FEF 50 ) were presented But the severe patients showed significant differences between heliox driven and compressed air driven for FVC, FEV 1, FEF 50 and partial pressure of oxygen (PaO 2) Conclusions Compared with the traditional inhalation of β 2 agonist therapy using compressed air driven, the method of inhaling β 2 agonist with heliox driven has more obvious benefits for those suffering from severe asthma This is likely due to the cooperative effects between inhaling heliox on its physical gas properties and improving delivery of β 2 agonist in the treatment of exacerbation of severe asthma Objective To evaluate the effectiveness of a helium oxygen mixture (79% He 21% O 2) as an aerosolizing compressed gas for β 2 agonist therapy in patients with an asthma exacerbation Methods Twenty four patients in the outpatient department with mild to moderate exacerbation of The patients were randomly divided into an experimental group (13 cases) and a control group (11 cases) The experimental group inhaled Berotec with heliox driven, and the control group inhaled Berotec with compressed air driven Eight hospitalized patients in the respiratory department with severe exacerbation of asthma were enrolled The patients inhaled Berotec with heliox driven or compressed air driven in a random order Results The results of spirometric parameters and arterial blood gas analysis were measured in the mild to moderate asthma patients, no statistical differences between the two groups for forced vital capacity (FVC), forced expired volume in on e second (FEV 1), and expiratory flow in 50% forced vital capacity (FEF 50) were presented But the severe patients showed significant differences between heliox driven and compressed air driven for FVC, FEV 1, FEF 50 and partial pressure of oxygen PaO 2) Conclusions Compared with the traditional inhalation of β 2 agonist therapy using compressed air driven, the method of inhaling β 2 agonist with heliox driven has more obvious benefits for those suffering from severe asthma This is likely due to the cooperative effects between inhaling heliox on its physical gas properties and improving delivery of β 2 agonist in the treatment of exacerbation of severe asthma