PURPOSE: To compare the clinical efficacy of a newly-designed spacer, AeroHaler® (Aerocare, Thailand)to an established space holding chamber, Aerochamber® (Trudell Medical, Canada) in Thai children with asthma.

METHODS: A double-blinded, experimental study was conducted at the Pediatric Chest Clinic, Ramathibodi Hospital. We recruited known cases of asthma, aged 6-15 years with history of significant bronchodilator response by ATS criteria. Patients were double-blinded randomized into 2 groups with blocked allocation. The pulmonary function tests were performed at baseline. 4 puffs of salbutamol MDI was used to test bronchial reversibility. The patients received bronchodilator through either Aerochamber® or AeroHaler® on the first day of study and through another on the next day. The pulmonary function tests were repeated at 15 and 30 minutes after bronchodilator given. Significant bronchodilator response is identified as >12% increment of force expiratory volume in 1 second (FEV1) from baseline. The mean FEV1 increment which reflects the efficacy of each space holding chamber in delivering bronchodilator was compared by paired T test.

RESULTS: Twenty children with median age of 9.1 years (range 7.0-12.0) were enrolled. Thirteen children were male. The mean baseline FEV1 in patients using Aerochamber® was 75.1±17.9% predicted and 77.6±16.8 % predicted in patients using AeroHaler® (p= 0.07). Using Aerochamber®, 10 children (50%) demonstrated bronchodilator response but only 4 of them (20%) showed bronchodilator response while using AeroHaler®. The FEV1 increment in patients using Aerochamber® was greater than that of AeroHaler® at both time points, 15 and 30 minutes, which maximal value found at 30 minutes. The mean increments of FEV1 using Aerochamber® and AeroHaler® were 9.97±9.36 % and 5.57±8.51 % respectively (p=0.02).

CONCLUSIONS: As assessment of FEV1 increment to demonstrate bronchodilator response in Thai children with asthma, Aerochamber® is superior to AeroHaler®.