November 2002 / Volume 47 / Number 11 / Page 1314
Nebulizer Therapy for Children: The Device-Patient Interface
IntroductionA therapeutic aerosol benefits the patient only if the medication deposits in the airway. Advances in nebulizer design have made them more efficient and "user friendly," but the greatest problem with administering aerosolized medication continues to be educating patients and caregivers to use aerosol devices properly and consistently. Misuse and nonuse are the greatest impediments to effective aerosol delivery. The respiratory pattern and degree of patient cooperation also profoundly affect aerosol deposition, and those effects are greatly magnified in small children. There are many misconceptions about nebulizer use and nebulizer equipment, even in teaching hospitals, and these can have serious consequences when patients do not receive the medication they need. This review discusses how airway physiology, nebulizer technology, and patient education relate to appropriate nebulizer use. Education is critically important, but unfortunately it is often a misunderstood or neglected part of aerosol administration.
Choice of Equipment
Aerosol Size and Airway Deposition
Special Medication Delivery Issues for Infants and Children
Airway Diameter and Particle Deposition
Patient Cooperation and Aerosol Delivery
Care of Nebulizer Equipment
Reasons for Nonadherance to Therapy
Choice of Equipment
Modern jet nebulizers were introduced in 1958, with the Wright nebulizer. In the last few years, nebulizer technology has rapidly evolved, improving the efficiency and ease of use of many of these devices. For nebulizer therapy to work well, the nebulizer must work well, the nebulizer-patient interface must work well, and patient must understand proper technique. This review focuses on the nebulizer-patient interface and problems associated with nebulizer therapy in children.
Nebulizer performance varies with diluent volume, operating flow, pressures, gas density, and nebulizer model. The residual volume of medicine that remains in commercial small-volume nebulizers ranges from 0.5 to 1.5 mL, depending on the specific device. By increasing the fill volume (usually by adding saline) a greater proportion of the medication can be nebulized. For example, with a 1 mL residual volume, a fill of 2 mL would have only 50% of the nebulizer charge available for nebulization, whereas a fill of 4 mL would make 75% of the medication available for nebulization. Many patients use a 2 mL unit dose of medication in the nebulizer without adding additional saline to optimize fill volume.