A fact-finding study of the inhalation techniques for pressurized aerosol metered-dose inhaler (MDI) use was carried out on 130 asthmatic patients who used the MDI From April 1993 to October 1993. Furthermore, the relationship between the degree of practice and the comprehension of the correct inhalation technique was also evaluated. Eight maneuvers to inhale correctly were considered and consisted of:(1) Removing the cap and shaking the MDI, (2) Holding the MDI upright and 4 cm in front of the open mouth, (3) Tilting the head back and breathing out, (4) Activating the MDI and then inhaling slowly for 5-6 seconds, (5) Holding the breath for 10 seconds, (6) Breathing out slowly, (7) Gargling in the thrioat, (8) Waiting 3 minutes and then chang hands before taking another puff.
The questionnaires were collected in 80 of 130 patients (61.5%) and there was a wide range in the percentages of patients correctly performing the individual maneuvers, as follows:(1) 88.8%, (2) 27.5%, (3) 42.5%, (4) 30.3%, (5) 47.5%, (6) 63.8%, (7) 17.5%, and (8) 33.8%. Three patterns were observed in the relationship between the degree of practice and the comprehension of the correct inhalation technique. One is that maneuvers (1), (5), and (6) could be easily carried out because of good comprehension. Second is that the maneuvers, such as (2), (3), (4), and (8), could not be carried out because of poor comprehension. Third is that maneuvers (7) could not be carried out in spite of good comprehension.
These results suggest that it is important to provide proper drug information and to educate patients on the correct inhalation techniques of MDI, in order to improve the clinical effectiveness and avoid any adverse effects of MDI based on improper application techniques.