This review demonstrates that incorrect DPI technique with established DPIs is common among patients with asthma and COPD, and suggests that poor inhalation technique has detrimental consequences for clinical efficacy. Regular assessment and reinforcement of correct inhalation technique are considered by health professionals and caregivers to be an essential component of successful asthma management. Improvement of asthma and COPD management could be achieved by new DPIs that are easy to use correctly and are forgiving of poor inhalation technique, thus ensuring more successful drug delivery.

Link to full study: https://clinicaltrials.gov/ct2/show/NCT02123667?term=NCT02123667&rank=1 relevance of SAD, which is present across all severity stages of asthma. It is particularly present in severe disease, likely reflecting structural lung changes that are not responsive toe the use of oral corticosteroids and/or high dose inhaled corticosteroids. Moreover, SAD relates to asthma stability, severity, quality of life, exacerbation rates and health care utilization and can be delineated by easyto-conduct, clinically applicable measures such as IOS and spirometry. Therefore, this aspect of asthma needs further consideration in the management of the disease.

Although the principles of asthma management are well established in Europe, the available data indicate that asthma in patients is not well controlled. Many patients derive incomplete benefit from their inhaled medication because they do not use inhaler devices correctly and this may compromise asthma control. The Aerosol Drug Management Improvement Team (ADMIT), incorporating clinicians from the UK, Germany, France, Italy, Spain and The Netherlands, reviewed published evidence to examine ways to improve the treatment of reversible airways disease in Europe. Data indicate that there is a clear need for specific training of patients in correct inhalation technique for the various devices currently available, and this should be repeated frequently to maintain correct inhalation technique. Devices which provide reassurance to patients and their physicians that inhalation is performed correctly should help to improve patient compliance and asthma control. Educational efforts should also focus on primary prescribers of inhaler devices. ADMIT recommends dissemination of information on the correct inhalation technique for each model of device by the use of an accessible dedicated literature base or website which would enable to match the appropriate inhaler to the individual patient. There is also a need for standardisation of prescribing practices throughout Europe. Regular checking of inhalation technique by prescribers is crucial as correct inhalation is one of the keystones of successful asthma management.

Aerosol inhalation is considered the optimal route for administering the majority of drugs for the treatment of obstructive airways diseases. A number of Pressurised Metered-Dose and Dry Powder Inhalers are available for this purpose. However, inhalation of therapeutic aerosols is not without difficulty; it requires precise instructions on the inhalation manoeuvre, which is different from spontaneous normal breathing. Also, the characteristics of the inhaler device have to be suitable for the user. Available data indicate a frequent lack of knowledge demonstrated by health professionals and patients on the inhalation manoeuvre and handling of inhalers, resulting in a reduction of therapeutic benefit. This paper reviews the literature concerning the fundamental aspects of inhaler devices, inhalation manoeuvre and device selection, in an attempt to increase the knowledge of, and to optimise the clinical use of, therapeutic inhalers.

Turbuhaler and Salbutamol-Diskus produce therapeutic doses at peak inspiratory flow (PIF) of >30 L/min. However, the optimum flow for Fluticasone-Diskus and Turbuhaler, in terms of total emitted dose and fine particle mass, is >60 L/min. The Turbuhaler achieved a higher output at this flow, as compared to Diskus. For pMDI 25 < PIF < 90 L/min, an actuation time of 0.0-0.2 sec is optimal. The aim of this study was to examine the incidence of optimum inhalation profiles, the effect of instruction, reproducibility, and the relationship between inhalation profiles and patient characteristics in stable asthmatics and mild/moderate/severe COPD patients. For each device, triplicate inhalation profiles were recorded during 6 sessions in a 10-week period. All patients achieved PIF > 30 L/min using Diskus. After instruction, all Diskus inhalations were performed with >60 L/min, except 7% of the inhalations of the severe COPD patients. At least 95% of the Turbuhaler inhalations was also performed with the minimum flow; however, 19% of the inhalations of the severe COPD patients were not optimally performed. The hand-lung coordination was inadequate in 40% of pMDI inhalation profiles, and 80% was performed with a too high flow. The reproducibility of PIF of both dry powder inhalers (DPIs) was very high (coefficient of variation = 4-10%). The reproducibility of the pMDI variables was lower (coefficient of variation = 9-18%). The major lung function variables predictive for PIF(diskus) and PIF(turbuhaler) were maximal inspiratory mouth pressure (MIP), PIF, and inspiratory capacity. No significant predictive lung function variables for PIF(pMDI) were found. Most patients performed reproducible optimum inhalation profiles through Diskus and Turbuhaler. However, in the severe COPD group, 7-19% of the patients were not able to generate the optimum flows through the DPIs. For these patients, a flow-independent aerosol delivery system might be more suitable. The majority of patients were using the pMDI incorrectly. Instruction had no effect. So, we concluded that the pMDI should not be used in these patient groups because of the coordination problems.