RT Journal Article
SR Electronic
T1 The bronchodilator response from inhaled terbutaline is influenced by the mass of small particles: a study on a dry powder inhaler (Turbuhaler)
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 253
OP 256
DO 10.1183/09031936.93.02030253
VO 2
IS 3
A1 G Persson
A1 JE Wiren
YR 1989
UL http://erj.ersjournals.com/content/2/3/253.abstract
AB This study was carried out to investigate if particles approximately less than 5 microns are optimal when delivered from a dry powder inhaler. It was performed as a cumulative dose response study of twelve asthmatic adults. Three different versions of a dry powder inhaler, Bricanyl Turbuhaler, were studied. Each inhaler delivered 0.5 mg of pure terbutaline sulphate with each dose. Out of this 0.5 mg, they delivered 90 micrograms, 40 micrograms and 5 micrograms, respectively, of particles approximately less than 5 microns with each dose at an inspiratory flow rate of 28 l.min-1. Terbutaline 0.5 mg, 0.5 mg, 1.0 mg and 2.0 mg was inhaled with a 30 min interval between the doses. Forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were measured 5 and 20 min after each dose. The bronchodilator response was greater with the inhaler delivering 90 micrograms of small particles with each dose than with the inhaler delivering 5 micrograms, thus confirming the importance of small (approximately less than 5 microns) particles.