we use mdi,spacers,masks and other devices to treat bronchial asthma
Are we using the correct technique?, It will be appropriatr to review our technique
Patients can be given the following simple instructions for obtaining maximum benefit fromtheir pressurized bronchodilators. They should be advised to shake the canister thoroughly;place the inhaler mouthpiece between the lips; breathe out steadily; fire the inhaler while taking a slow, deep inhalation; and hold the breath at full inspiration while slowly counting to 10.
Our results show that maximal bronchodilatation, as indicated by percentage increase in
FEV1, is achieved with a slow, full breath and 10 seconds of breath-holding, the lung volume
at which the aerosol is inhaled being unimportant. With rapid inhalation, bronchodilatation
was significantly reduced irrespective of the breath-holding pause or the lung volume of aerosol inhalation. This may occur because the majority of aerosol particles entering the lungs during rapid inhalations are deposited in large central airways by inertial impaction (Goldberg & Lourenco 1973) and only a small number are able to penetrate to more peripheral regions, where beta-adrenergic bronchodilators are believed to have their site of action (Hensley et al. 1978).