Inhaler devices in infants and children: challenges and solutions.

Abstract

THE ISSUES surrounding the use of inhaled therapy in children are essentially the same as those in adults. Patients must be given a device that they can and will use effectively—the prescribed dose should be the lowest dose that works. Although there are considerable physiological differences between young children and adults, the most important differences are the changes in cognitive and emotional developmental that occur during the first few years of life. This article will concentrate on important patientrelated factors that impact on aerosol delivery in patients of all ages and then consider specific issues related to infants and children. Obtaining a clinically useful therapeutic response when using inhaled medication to treat pulmonary disease involves administering an appropriate medication and then ensuring that sufficient (but not too much) drug reaches the lungs to produce a therapeutic response. While it is clear that we are able to achieve this in all age groups using existing technology, there are many, many patients who fail to derive significant benefit from the therapeutic options available. While aerosol scientists tend to focus on aspects such as fine particle fraction inspiratory flow, and airway modeling to try and find ways of improving delivery systems, it is patient behavior and the failure of current devices to address the basic needs of most patients that is the single most important factor. To reliably and consistently deliver aerosolized drug to their lungs, patients must be provided with a delivery system able to generate an aerosol that contains particles that can reach and deposit in the lower airways. Unfortunately, with current delivery systems, this alone is insufficient, since the devices are not intuitive to use, and therefore considerable additional input is required from health care professionals to ensure that the patient can and will use the device effectively. This is an issue for all age groups. Though there has been considerable focus on the problems associated with treating young children, the problems are probably greater in the elderly, in whom cognitive issues and physical limitations conspire to impair effective drug delivery in many patients using portable inhalers.1–4 The simplicity and intuitiveness of nebulizers explains their popularity in this age group.