Evaluation Of The Bronchodilator Effect And Side Effect Profile Of A Salbutamol Dry Powder Inhaler Device: A Prospective Observational Study
G Du Toit, G Brown, B Joshua, C Motala, H Nell, E Weinberg
Citation
G Du Toit, G Brown, B Joshua, C Motala, H Nell, E Weinberg. Evaluation Of The Bronchodilator Effect And Side Effect Profile Of A Salbutamol Dry Powder Inhaler Device: A Prospective Observational Study. The Internet Journal of Pediatrics and Neonatology. 2003 Volume 4 Number 1.
Abstract
Dry Powder Inhalation devices are currently used for the administration of inhaled Corticosteroids (ICS) and short acting B2 agonists (SABA). Most generic asthma medications are only available as Metered Dose Inhalers (MDI), with the consequence that Dry Powder Inhaler (DPI) devices are infrequently a therapeutic option in regions where medication costs are the overriding concern. Potential advantages of the DPI inhalation device as compared to MDI and nebulisation include; affordability, ease of use, reduced administration time and lack of CFC propellants.
Introduction
The aims of the study were to assess the bronchodilator efficacy and side effect profile of a low cost salbutamol DPI device when used in a busy Allergy Clinic. In addition, we sought to assess the attitudes of nursing staff, parents and patients, after having used the DPI device.
Methods
For inclusion into the study, patients must have been able to activate the DPI through generating sufficient inspiratory flow. All consenting patients with clinical signs of asthma or if the FEV1 was <80% of predicted for height, received salbutamol 200ug administered using the DPI device. If symptoms persisted or FEV1 remained <80% of predicted, the DPI was repeated (+10 minutes). Patients with no improvement in FEV1 after 2 administrations of DPI, were considered treatment failures, and would have received wet nebulisation to access for “reserve bronchodilator capacity”. This treatment regimen is standard RCCH Allergy Clinic practice. Primary efficacy variable was mean change in FEV1 15 minutes post 1st administration DPI, if required FEV1 +10 minutes post second DPI administration and after wet nebulisation. Secondary variables were
Results
Fifty-one symptomatic asthmatic children (28 male/23 female) were enrolled. Mean age was 11 years (range 7 -16). Eighty four percent of patients were on ICS medications and in addition, 24% received long acting B2 agonists. Recent cough and wheeze were reported in 80 % and 55% of patients respectively. The mean FEV1 pre bronchodilator was 1.27L (0.5L). This was significantly lower than the mean previous best FEV1 of 1.53L (0.4L), p<001. The mean change in FEV1 15 minutes post DPI, compared to baseline, was 370 mL (CI 296 to 446mL) p<0.001. Four percent of patients required a second administration of the DPI with a mean additional change at 25 minutes of 100 mL (CI -57 to 255), p>0.05. No patients required wet nebulisation. Adverse events reported were tremor in 4% and nausea in 8% of patients. Ninety eight percent of patients perceived the device easy to use and 94% of patients preferred the DPI to the MDI-Spacer combination. Ninety five percent of caregivers expressed confidence in the DPI device, were it to be required for the relief of acute asthma.
Discussion
The findings of this independent study, confirm the favourable RCCH Allergy and Asthma Clinic experience when using the low cost salbutamol DPI (Cipla Medpro®) device for the acute relief of symptomatic asthma. In spite of the possible bias introduced by the open label study design we conclude that the device was both effective and safe in children with symptomatic asthma. In addition, the Salbutamol DPI device was considered to be effective and easy to use, by patients and staff alike. These findings are particularly helpful when cost constraints restrict the use of dry powdered inhalers.