Aerosol therapy and the fighting toddler: is administration during sleep an alternative?

Cartoons to improve young children's cooperation with inhaled corticosteroids: A preliminary study

INTRODUCTION

The objective of this pilot study was to evaluate if animated cartoons could increase the cooperation of young children with asthma during the delivery of their inhaled corticosteroids (ICS).

METHODS

Subjects were children aged 6-47 months having a physician diagnosis of asthma, who required an ICS therapy delivered through a pMDI/spacer twice a day for at least 2 months. Families who reported on a questionnaire that their child was frequently crying or moving during treatment delivery were asked to participate in a prospective, cross-over, randomized study. After a first week of run-in, children watched alternatively, during the delivery of ICS, either an animated cartoon for 7 days and a black screen video for another 7 days. The main outcome was the median percentage of time of non-cooperation, defined by the length of time the child was crying and/or moving divided by the length of time required for delivering ICS.

RESULTS

Parents of 50 children out of 113 (44%) reported that their child was frequently crying or moving during treatment delivery. Among these 50 children, 11 (22%) completed the study. The median percentages of time of non-cooperation (IQR 1-3) were 0% (0-3) and 56% (40-97) during the distraction and control periods, respectively, in the first group, and 100% (98-100) and 0% (0-5) during the control and distraction periods, respectively, in the second group. Animated cartoons increased cooperation up to 97% (55-100%) (P = 0.008).

CONCLUSIONS

Bad cooperation among young children with asthma during the delivery of their treatment can be dramatically improved by the use of animated cartoons.

Drug delivery interfaces: A way to optimize inhalation therapy in spontaneously breathing children

There are several different types of drug delivery interfaces available on the market. Using the right interface for aerosol drug delivery to children is essential for effective inhalation therapy. However, clinicians usually focus on selecting the right drug-device combination and often overlook the importance of interface selection that lead to suboptimal drug delivery and therapeutic response in neonates and pediatrics. Therefore, it is necessary to critically assess each interface and understand its advantage and disadvantages in aerosol drug delivery to this patient population. The purpose of this paper is to provide a critical assessment of drug delivery interfaces used for the treatment of children with pulmonary diseases by emphasizing advantages and problems associated with their use during inhalation therapy.

Pressurised metered dose inhaler-spacer technique in young children improves with video instruction

The importance of good device technique to maximise delivery of aerosolised medications is widely recognised. Pressurised metered dose inhaler (pMDI)-spacer technique was investigated in 122 children, aged 2-7 years, with asthma. Eight individual steps of device technique were evaluated before and after viewing an instructional video for correct device technique. Video measurements were repeated every three months for nine months. Device technique improved directly after video instruction at the baseline study visit (p < 0.001) but had no immediate effect at subsequent visits. Additionally, pMDI-spacer technique improved with successive visits over one year for the group overall as evidenced by increases in the proportion of children scoring maximal (p = 0.02) and near-maximal (p = 0.04) scores.

CONCLUSION

Repeated video instruction over time improves inhaler technique in young children.

WHAT IS KNOWN

• Correct device technique is considered essential for sufficient delivery of inhaled medication. • Poor inhaler use is common in young asthmatic children using pressurised metered dose inhalers and spacers. What is New: • Video instruction could be used as a strategy to improve device technique in young children.

Optimization and Dose Estimation of Aerosol Delivery to Non-Human Primates

BACKGROUND

In pre-clinical animal studies, the uniformity of dosing across subjects and routes of administration is a crucial requirement. In preparation for a study in which aerosolized live-attenuated measles virus vaccine was administered to cynomolgus monkeys (Macaca fascicularis) by inhalation, we assessed the percentage of a nebulized dose inhaled under varying conditions.

METHODS

Drug delivery varies with breathing parameters. Therefore we determined macaque breathing patterns (tidal volume, breathing frequency, and inspiratory to expiratory (I:E) ratio) across a range of 3.3-6.5 kg body weight, using a pediatric pneumotachometer interfaced either with an endotracheal tube or a facemask. Subsequently, these breathing patterns were reproduced using a breathing simulator attached to a filter to collect the inhaled dose. Albuterol was nebulized using a vibrating mesh nebulizer and the percentage inhaled dose was determined by extraction of drug from the filter and subsequent quantification.

RESULTS

Tidal volumes ranged from 24 to 46 mL, breathing frequencies from 19 to 31 breaths per minute and I:E ratios from 0.7 to 1.6. A small pediatric resuscitation mask was identified as the best fitting interface between animal and pneumotachometer. The average efficiency of inhaled dose delivery was 32.1% (standard deviation 7.5, range 24%-48%), with variation in tidal volumes as the most important determinant.

CONCLUSIONS

Studies in non-human primates aimed at comparing aerosol delivery with other routes of administration should take both the inter-subject variation and relatively low efficiency of delivery to these low body weight mammals into account.

Pediatric in vitro and in silico models of deposition via oral and nasal inhalation

Respiratory tract deposition models provide a useful method for optimizing the design and administration of inhaled pharmaceutical aerosols, and can be useful for estimating exposure risks to inhaled particulate matter. As aerosol must first pass through the extrathoracic region prior to reaching the lungs, deposition in this region plays an important role in both cases. Compared to adults, much less extrathoracic deposition data are available with pediatric subjects. Recently, progress in magnetic resonance imaging and computed tomography scans to develop pediatric extrathoracic airway replicas has facilitated addressing this issue. Indeed, the use of realistic replicas for benchtop inhaler testing is now relatively common during the development and in vitro evaluation of pediatric respiratory drug delivery devices. Recently, in vitro empirical modeling studies using a moderate number of these realistic replicas have related airway geometry, particle size, fluid properties, and flow rate to extrathoracic deposition. Idealized geometries provide a standardized platform for inhaler testing and exposure risk assessment and have been designed to mimic average in vitro deposition in infants and children by replicating representative average geometrical dimensions. In silico mathematical models have used morphometric data and aerosol physics to illustrate the relative importance of different deposition mechanisms on respiratory tract deposition. Computational fluid dynamics simulations allow for the quantification of local deposition patterns and an in-depth examination of aerosol behavior in the respiratory tract. Recent studies have used both in vitro and in silico deposition measurements in realistic pediatric airway geometries to some success. This article reviews the current understanding of pediatric in vitro and in silico deposition modeling via oral and nasal inhalation.

Nasal versus oral aerosol delivery to the "lungs" in infants and toddlers

OBJECTIVES

The oral route has been considered superior to the nasal route for aerosol delivery to the lower respiratory tract (LRT) in adults and children. However, there are no data comparing aerosol delivery via the oral and nasal routes in infants. The aim of this study was to compare nasal and oral delivery of aerosol in anatomically correct replicas of infants' faces containing both nasal and oral upper airways.

METHODS

Three CT-derived upper respiratory tract ("URT") replicas representing infants/toddlers aged 5, 14 and 20 months were studied and aerosol delivery to the "lower respiratory tract" (LRT) by either the oral or nasal route for each of the replicas was measured at the "tracheal" opening. A radio-labeled (99mDTPA) normal saline solution aerosol was generated by a soft-mist inhaler (SMIRespimat® Boehringer Ingelheim, Germany) and aerosol was delivered via a valved holding chamber (Respichamber® TMI, London, Canada) and an air-tight mask (Unomedical, Inc., McAllen, TX). A breath simulator was connected to the replicas and an absolute filter at the "tracheal" opening captured the aerosol representing "LRT" dose. Age-appropriate mask dimensions and breathing patterns were employed for each of the airway replicas. Two different tidal volumes (V_t ) were used for comparing the nasal versus oral routes.

RESULTS

Nasal delivery to the LRT exceeded that of oral delivery in the 5- and 14-month models and was equivalent in the 20-month model. Differences between nasal and oral delivery diminished with "age"/size. Similar findings were observed with lower and higher tidal volumes (V_t ).

CONCLUSION

Nasal breathing for aerosol delivery to the "LRT" is similar to, or more efficient than, mouth breathing in infant/toddler models, contrary to what is observed in older children and adults. Pediatr Pulmonol. 2015; 50:276-283. © 2014 Wiley Periodicals, Inc.

Breathing easier: addressing the challenges of aerosolizing medications to infants and preschoolers

An increasing number of patients are dependent on aerosolized therapy to manage pulmonary diseases, including asthma, cystic fibrosis, and pulmonary arterial hypertension. An aerosol therapy is only useful if it can be appropriately and consistently delivered in the desired dose to the lower respiratory tract. Many factors affect this deposition in young children, including anatomical and physiologic differences between adults and children, patient-mask interface issues, the challenge of administering medication to uncooperative children, and behavioral adherence. Moreover, the techniques used to assess aerosol delivery to pediatric patients need to be carefully evaluated as new therapies and drug-device combinations are tested. In this review, we will address some of the challenges of delivering aerosolized medications to pediatric patients.

Feasibility of aerosol drug delivery to sleeping infants: a prospective observational study

OBJECTIVES

Delivery of inhaled medications to infants is usually very demanding and is often associated with crying and mask rejection. It has been suggested that aerosol administration during sleep may be an attractive alternative. Previous studies in sleeping children were disappointing as most of the children awoke and rejected the treatment. The SootherMask (SM) is a new, gentle and innovative approach for delivering inhaled medication to infants and toddlers. The present pilot study describes the feasibility of administering inhaled medications during sleep using the SM.

DESIGN

Prospective observational study.

SETTING

Out patients.

PARTICIPANTS

13 sleeping infants with recurrent wheezing who regularly used pacifiers and were <12 months old.

INTERVENTION

Participants inhaled technetium99mDTPA-labelled normal saline aerosol delivered via a Respimat Soft Mist Inhaler (SMI) (Boehringer-Ingelheim, Germany) and SM + InspiraChamber (IC; InspiRx Inc, New Jersey, USA).

OUTCOMES

The two major outcomes were the acceptability of the treatment and the lung deposition (per cent of emitted dose).

RESULTS

All infants who fulfilled the inclusion criteria successfully received the SM treatment during sleep without difficulty. Mean lung deposition (±SD) averaged 1.6±0.5% in the right lung.

CONCLUSIONS

This study demonstrated that the combination of Respimat, IC and SM was able to administer aerosol therapy to all the sleeping infants who were regular pacifier users with good lung deposition. Administration of aerosols during sleep is advantageous since all the sleeping children accepted the mask and ensuing aerosol therapy under these conditions, in contrast to previous studies in which there was frequent mask rejection using currently available devices.

CLINICAL TRIAL REGISTRY

NCT01120938.

Asthma medication delivery: mists and myths

Asthma is usually treated with inhaled corticosteroids (ICS) and bronchodilators generated from pressurized metered dose inhalers (pMDI), dry powder inhalers (DPI), or nebulizers. The target areas for ICS and beta 2-agonists in the treatment of asthma are explained. Drug deposition not only depends on particle size, but also on inhalation manoeuvre. Myths regarding inhalation treatments lead to less than optimal use of these delivery systems. We discuss the origin of many of these myths and provide the background and evidence for rejecting them.

[Inhalation devices: characteristics, modeling, regulation and use in routine practice. GAT Aerosolstorming, Paris 2011]

Aerosoltherapy is a first-line treatment for chronic obstructive respiratory diseases such as asthma and COPD. Treatment modalities and devices are varied and the choice of the device must be adapted to and optimized for every patient. Spacers can be used for some categories of patients for whom the use of other devices turns out to be complicated. The improvement of these treatments requires the optimization of the lung deposition of inhaled particles; lung modeling plays an essential role in the understanding of the mechanisms of flow in the airways. Regulations must frame prescription of inhaled treatments to optimize its quality and, thus, the care for these chronic diseases. Many generally-accepted ideas concerning these treatments turn out to be false. Inhaled treatments are constantly evolving, both pharmacologically and technologically.

Guidelines for aerosol devices in infants, children and adults: which to choose, why and how to achieve effective aerosol therapy

Multiple types of aerosol devices are commonly used for the administration of medical aerosol therapy to patients with pulmonary diseases. All of these devices have been shown to be effective in trials where they are used correctly. However, failure to operate any of these devices properly has been associated with poor clinical response and limited patient adherence to therapy. Therefore, the selection of the best aerosol device for the individual patient is very important for optimizing the results of medical aerosol therapy. This article presents the rationale for selecting the most appropriate aerosol device to administer inhaled drugs in specific patient populations, with emphasis on patient-, drug-, device- and environment-related factors and with a comparison between the available devices. The following recommendations for the selection of the 'best' aerosol device for each patient population are intended to help clinicians gain a clear understanding of the specific issues and challenges so that they can optimize aerosol drug delivery and its therapeutic outcomes in patients.

Aerosol therapy in infants and toddlers: past, present and future

Infants and toddlers are a unique subpopulation with regard to aerosol therapy. There are various anatomical, physiological and emotional factors peculiar to this age group that present significant difficulties and challenges for aerosol delivery. Most studies on the factors determining lung deposition of therapeutic aerosols are based on data from adults or older children, which cannot simply be extrapolated directly to infants. The present review describes why infants/toddlers are very different with respect to two major issues - namely their anatomy/physiology and their behavior. We suggest possible solutions and future research directions aimed at improving clinical outcomes of aerosol therapy in this age group.

Deposition of albuterol aerosol generated by pneumatic nebulizer in the Sophia Anatomical Infant Nose-Throat (SAINT) model

PURPOSE

To quantify distribution of albuterol aerosol generated by a pneumatic nebulizer within the nose and lungs of a model of a 9-month-old child (SAINT) and aerosol loss to the environment, during simulated breathing at increasing tidal volumes (TVs).

METHODS

(99m)technetium-labeled albuterol aerosol was generated by an IPI nebulizer with face-mask. Deposition was quantified as a percentage of emitted dose using gamma scintigraphy.

RESULTS

Lung deposition was similar for all TVs, averaging 7.17 +/- 0.01%, 9.34 +/- 0.01% and 9.41 +/- 0.02% at 50, 100 and 200 mL TV, respectively. In contrast, nose deposition increased significantly with TV, averaging 4.40 +/- 0.02%, 11.39 +/- 0.02% and 22.12 +/- 0.02% at 50 mL, 100 mL and 200 mL TV, respectively (all p < 0.0167). Aerosol loss to the environment was significantly lower at 200 mL TV (53.81 +/- 0.04%), compared to 50 mL (71.99 +/- 0.02%) (p < 0.0167).

CONCLUSIONS

Our results suggest that nasal deposition of albuterol aerosol generated by a pneumatic nebulizer in 9-month-old infants may be significantly affected by changes in TV, ranging between 50 to 200 mL, whereas total lung deposition may not be affected. These results also predict that environmental losses would be highest when administering to a child breathing at 50 mL TV. These data should be useful to companies who are working to improve aerosol delivery systems to treat infants.

Inhaled corticosteroid therapy with nebulized beclometasone dipropionate

Inhaled corticosteroids (ICS) are the most effective anti-inflammatory agents for the management of chronic persistent asthma and are therefore recommended as first-line antiasthmatic therapy in children and adults. In various settings, the administration of ICS via nebulizer rather than hand-held inhaler (HHI) may have certain advantages, as many patients with HHI fail to use these devices properly or efficiently. In particular, young children, the elderly, the acutely ill, and those with restricted dexterity may be unable to coordinate inhalation with actuation of the device or to generate sufficient inspiratory flow to operate breath-actuated devices effectively. Compliance with nebulized therapy may also be better than that with a pressurized metered-dose inhaler (pMDI) plus spacer. Systematic reviews conclude that there is no significant difference in clinical effects between nebulizers and HHI. Performance and clinical effect of nebulization are influenced by several technical aspects such as the nebulizer-drug combination, nebulizer type, output and lung deposition. Among the currently available ICS, nebulized beclometasone dipropionate (BDP) has been in clinical use for more than 35 years, and has demonstrated marked clinical efficacy and a favorable tolerability profile in children and adults with chronic persistent asthma. The clinical efficacy of nebulized beclometasone is discussed in the present review using data from 13 published studies, which included a total of 1250 patients. Three multicenter, randomized, double-blind studies showed that nebulized BDP is as effective as BDP via pMDI plus spacer in a 2:1 dose ratio. Controlled trials involving 497 adults and children demonstrated similar clinical efficacy between nebulized BDP and either nebulized fluticasone propionate or nebulized budesonide. In all these trials, treatment-related adverse effects were generally uncommon, most were mild-to-moderate in severity, and most were associated with the respiratory system. Meta-analyses show that BDP, like other inhaled corticosteroids, has no major influence on patient height, urinary cortisol concentration, or bone metabolism, thus suggesting the absence of growth retardation or any marked effect on adrenal function or the hypothalamic-pituitary-adrenal axis when used in the approved dose range. Overall, nebulized BDP appears to have a particularly important place in asthma therapy: as a general alternative to HHIs (e.g. in patients with poor HHI compliance); when patients such as children or the elderly are unable to operate HHIs because of poor hand-lung coordination, lack of cooperation, or low inspiratory flow rate; and when high dosages of ICS are required, such as in adults with severe, corticosteroid-dependent asthma.

Aerosol delivery of nebulised budesonide in young children with asthma

BACKGROUND

Lung deposition of inhaled steroids, likely to be of benefit in the anti-inflammatory treatment of asthma in young children, is low. This is explained by age specific anatomical and physiological characteristics as well as poor cooperation with aerosol therapy. However, total lung deposition and the ratio of lung deposition to oropharyngeal deposition are key determinants of clinical efficacy and of systemic side effects of aerosolized drugs.

OBJECTIVES

The aim of this study was to determine lung deposition and ratio of lung deposition to oropharyngeal deposition using a modified vibrating membrane nebuliser to deliver budesonide with a small particle size, taking into account the needs of young children.

PATIENTS AND METHODS

Ten asthmatic children (5 males), mean age 20.3 months (range 6-41 months) inhaled radiolabelled budesonide (MMD 2.6microm) through a modified vibrating membrane nebuliser (modified PARI e-Flow). Lung deposition expressed as a percentage of the emitted dose was measured using scintigraphy and the ratio of lung deposition to oropharyngeal deposition was calculated.

RESULTS

Mean lung deposition (SD) expressed as percentage of emitted dose and mean lung to oropharyngeal deposition ratio (SD) in quietly breathing children (n=5) and in children crying during inhalation were 48.6% (10.5) versus 20.0% (10.9), and 1.0 (0.3) versus 0.3 (0.2), respectively.

CONCLUSIONS

We have shown that by using an improved age-adjusted complementary combination of delivery device and drug formulation to deliver small particles, lung deposition and ratio of lung deposition to oropharyngeal deposition in young asthmatic children is highly improved. But the main factor limiting aerosol delivery in this age group remains cooperation.

Appropriate face models for evaluating drug delivery in the laboratory: the current situation and prospects for future advances

The laboratory evaluation of inhalers with facemasks for patient interface is so complex that testing without a facemask is generally undertaken, a practice that has been advocated in one standard. However, the facemask itself can profoundly influence medication delivery. A systematic review of the literature was undertaken to establish the development history of face models for the evaluation of facemasks used with inhalers and accessories. Initial attempts to simulate the facemask-face boundary employed a circular, firm rubber flange plate upon which the facemask was located. However, such models did not represent dead volume accurately, which is particularly important when assessing infant use. Subsequent developments included the creation of more realistic facial features, enabling the aerosol leaving the inhaler to be quantified at the facemask. In one instance (SAINT model), an anatomically correct nasopharyngeal cavity has been combined with a model face, enabling assessment of medication delivery to be extended to the lower respiratory tract. However, it is necessary either to apply sealants or to compress the facemask beyond normal to eliminate leakage with the rigid facial structure that is incomplete above the bridge of the nose. An oral-breathing infant full-face model (ADAM) intended to be used to quantify emitted mass at the patient interface incorporates flexible facial features to overcome this limitation. There is a need to extend the flexible face approach to other models that may be developed in the future for testing facemasks, whether or not they incorporate anatomically correct realizations of the upper respiratory tract.

Review of optimal characteristics of face-masks for valved-holding chambers (VHCs)

Inhaled drugs are frequently given to infants and young children with a pressurized metered-dose inhaler (pMDI) attached to a valved-holding chamber (VHC) with face mask. In young children and infants who cannot breathe through a mouthpiece, the face mask serves as the interface between the patient and the VHC. Although the mask interface is one of the most important factors determining the dose of medication delivered from the VHC to the nose and mouth in these patients, its optimal characteristics are not well known. Recent studies clearly identify several face mask factors that determine the success or failure of drug delivery with these devices. This review summarizes the most important features of an optimal mask design such as: face seal/leak, volume of dead space, contour, flexibility, transparency, weight and cost. By optimizing these characteristics it should be possible to improve mask design. This will maximize the magnitude and reduce the variability of the dose presented to the respiratory tract while making the mask more comfortable and patient/caregiver-friendly.

Aerosol therapy: the special needs of young children

Efficient aerosol therapy in young children is a challenge. The aerosol administration method requires special features, because young children can not perform an inhalation manoeuvre, breath usually through the nose and may be distressed during the administration. The prescribing clinician should be aware of the advantages and disadvantages of the different inhalation devices available, in order to select the proper device for each individual patient. For maintenance asthma therapy in young children the pressurized metered dose inhaler (pMDI) combined with spacer is the first choice for delivering aerosols. A facemask can be attached if a child is unable to breath through the mouth. A small leak of the facemask can reduce the dose delivered dramatically, therefore a good seal is crucial. Lung deposition can be improved by using a pMDI with extra-fine particles. However, even if the most optimal device is chosen, cooperation during administration remains the most important determinant for efficient drug delivery. During crying the dose to the lungs is minimal. Optimal aerosol delivery to the lungs of young children can be achieved with a good facemask seal, good cooperation of the child, with quiet breathing and an aerosol with small particles.

Paediatric pulmonary drug delivery: considerations in asthma treatment

Aerosol therapy, the preferred route of administration for glucocorticosteroids and short-acting beta(2)-adrenergic agonists in the treatment of paediatric asthma, may be given via nebulisers, metered-dose inhalers and dry powder inhalers. For glucocorticosteroids, therapy with aerosolised medication results in higher concentrations of drug at the target organ with minimal systemic side effects compared with oral treatments. The dose of drug that reaches the airways in children with asthma is dependent on both the delivery device and patient-related factors. Factors that affect aerosol drug delivery are reviewed briefly. Advantages and disadvantages of each device and device-specific factors that influence patient preferences are examined. Although age-based device recommendations have been made, the optimal choice for drug delivery is the one that the patient or caregiver prefers to use, can use correctly and is most likely to use consistently.

Aerosol therapy by pressured metered-dose inhaler-spacer in sleeping young children: to do or not to do?

One third of young children are distressed during inhalation therapy. It has been suggested that administration during sleep could be a good alternative for these children. A laboratory study in our department using an infant upper airway model showed significantly higher lung doses from a pressured metered-dose inhaler (pMDI)-spacer for sleep-breathing patterns compared with wake-breathing patterns.

OBJECTIVE

We set up a daily life study to investigate the feasibility of aerosol administration by means of pMDI-spacer in sleeping young children.

DESIGN

Over a period of 3 weeks, 30 children (age range, 6 to 23 months) with recurrent wheeze daily inhaled 1 puff of budesonide aerosol (200 mug) while awake and 1 puff during sleep. Filters positioned between the chamber and the facemask trapped the budesonide aerosol. Parents scored the child's asthma symptoms, degree of cooperation, and feasibility of administration on diary cards.

RESULTS

In 69% of the sleep administrations, the children woke up, and in 75% of these cases the children were distressed. The mean filter dose (expressed as the percentage of the nominal dose) while awake was 47%, and during sleep it was 16% (p = 0.007). The median within-subject dose variability while awake was 50%, and during sleep it was 110% (p = 0.007).

CONCLUSION

Aerosol administration by means of pMDI-spacer during sleep offers no advantage and is not a feasible treatment option in most young children.

Comparison of Three Valved Holding Chambers for the Delivery of Fluticasone Propionate–HFA to an Infant Face Model

The purpose of this study was to compare three valved holding chambers (VHC) with facemasks attached. One VHC (AeroChamber Max[TM] with medium mask) was made with materials that dissipate surface electrostatic charge, and the others (OptiChamber Advantage and ProChamber[TM] with pediatric facemask) were made from non-conducting materials. The OptiChamber Advantage and ProChamber VHCs were each washed with an ionic detergent and drip dried before testing to minimize surface electrostatic charge. The AeroChamber Max VHCs were tested "out of the package" and also after wash, rinse, and drying. An infant face model incorporating an electrostatic filter in the oral cavity was connected to a breath simulator using a standard waveform for a small child. The fit of each VHC with facemask was demonstrated by agreement of inspiratory flow measurements between a pneumotachograph connected to the system with those set on the simulator. An HFA-fluticasone propionate metered dose inhaler (MDI; 125 microg/dose) was inserted into the VHC, two actuations were delivered, and the filters were subsequently assayed using high-pressure liquid chromatography (HPLC). Testing and sample assay order was randomized, and HPLC assays were undertaken blinded. Drug delivery efficiency expressed as a percentage of the total dose of fluticasone propionate (250 microg) for the AeroChamber Max VHC "out-of-the-package" was 22.0(0.7)% (mean [99% CI]) and 21.2(1.5)% when pre-washed/rinsed. Results for the pre-washed ProChamber and OptiChamber Advantage VHCs were 10.2(0.55)% and 8.8(1.9)%, respectively. The more efficient delivery of medication via VHCs made from electrostatic charge dissipative materials should be considered when choosing doses for small children.

In VitroDetermination of the Optimal Particle Size for Nebulized Aerosol Delivery to Infants

We investigated the in vitro influence of breathing patterns on lung dose (LD) and particle size distribution in an infant upper airway cast model in order to determine the optimal particle size for nebulized aerosol delivery to infants. Budesol (nebulizer solution of budesonide) delivery from a perforated vibrating membrane nebulizer (eFlow Baby functional prototype) through an upper airway cast of a nine month old infant (SAINT-model) was measured at a fixed respiratory rate (RR) of 30 breaths per minute (bpm) and a tidal volume (Vt) of 50, 100, and 200 mL, respectively, and at a fixed Vt of 100 mL and a RR of 30, 60, and 78 bpm, respectively. LD expressed as a percentage of the nominal dose (ND; range, 5.8-30.3%) decreased with increasing Vt (p < 0.001) and with increasing RR (p < 0.001). Median mass aerodynamic diameter (MMAD) after passage (range, 2.4-3.4 microm) through the upper airway cast showed a negative correlation with increasing Vt (p < 0.001) and with increasing RR (p = 0.015). Particles available as LD for all simulated breathing pattern showed a particle size distribution with a MMAD of 2.4 microm and a geometric standard deviation (GSD) of 1.56. From our in vitro study, we conclude that the optimal particle size for nebulized aerosols for inhalation therapy for infants should have a MMAD of <2.4 microm.

Factors guiding the choice of delivery device for inhaled corticosteroids in the long-term management of stable asthma and COPD: focus on budesonide

Inhaled corticosteroids (ICSs) have become the mainstay of chronic controller therapy to treat airways inflammation in asthma and to reduce exacerbations in chronic obstructive pulmonary disease. An array of ICSs are now available that are aerosolized by a range of delivery systems. Such devices include pressurized (or propellant) metered-dose inhalers (pMDIs), pMDIs plus valved holding chambers or spacers, breath-actuated inhalers, and nebulizers. More recently, dry-powder inhalers (DPIs) were developed to help overcome problems of hand-breath coordination associated with pMDIs. The clinical benefit of ICSs therapy is determined by a complex interplay between the nature and severity of the disease, the type of drug and its formulation, and characteristics of the delivery device together with the patient's ability to use the device correctly. The ICSs budesonide is available by pMDI, DPI, and nebulizer-allowing the physician to select the best device for each individual patient. Indeed, the availability of budesonide in three different delivery systems allows versatility for the prescribing physician and provides continuity of drug therapy for younger patients who may remain on the same ICSs as they mature.

Deposition of aerosols in infants and children

There is still a lack of knowledge in the field of aerosol therapy in children, particularly in young children. The amount of drug delivered from a commercially available inhalation device that reaches the lungs of children is generally low. The choice of an optimal combination of delivery device and drug formulation based on individual patient related factors is crucial. Aerosols with a small MMAD and a narrow GSD are required for a sufficient inhalation therapy in early childhood. The development of combinations of delivery devices and drug formulations fulfilling the requirements for an efficient inhalation therapy in young children is likely to increase the therapeutical options in this age group.