The conventional ultrasonic nebulizer proved inefficient in nebulizing a suspension

Recalibrating Perceptions and Attitudes Toward Nebulizers versus Inhalers for Maintenance Therapy in COPD: Past as Prologue

Aerosol therapy administered via handheld inhaler or nebulizer device has long been standard for the treatment of chronic obstructive pulmonary disease (COPD), both for maintenance therapy and for management of acute exacerbations. Of the 2 options for drug delivery, inhaler devices are the most widely used for ambulatory patients with COPD as they are small, portable, and convenient and offer an array of medication options. They are, however, prone to suboptimal inhalation technique and use errors, which decrease the amount of medication delivered, compromise efficacy, and adversely affect clinical outcomes. Nebulizers are less often employed for aerosol delivery than inhalers, particularly in the home environment. Considered bulky and expensive, nebulizers have historically had limited medication options compared with inhalers. Nonetheless, nebulizers may be preferred over inhalers in specific patient populations, such as in patients with poor lung function, lack of hand-breath coordination, or cognitive impairment. Furthermore, technological advances and development of new nebulizer-compatible medications are shifting the benefit equation for nebulizers versus inhalers in a way that merits reconsideration of the role of nebulizers in the maintenance treatment of COPD. Using the available literature, this state-of-the-art review critically evaluates the benefits and limitations of aerosol therapy delivery via inhaler or nebulizer for patients with COPD; describes the factors that may influence the benefit equation, including current advances in nebulizer technology and future developments; and provides insights on implementation of nebulizer therapy in clinical practice.

Administration of airborne pathogens in non-human primates

PURPOSE

Airborne pathogen scan penetrate in human respiratory tract and can cause illness. The use of animal models to predict aerosol deposition and study respiratory disease pathophysiology is therefore important for research and a prerequisite to test and study the mechanism of action of treatment. NHPs are relevant animal species for inhalation studies because of their similarities with humans in terms of anatomical structure, respiratory parameters and immune system.

MATERIALS AND METHODS

The aim of this review is to provide an overview of the state of the art of pathogen aerosol studies performed in non-human primates (NHPs). Herein, we present and discuss the deposition of aerosolized bacteria and viruses. In this review, we present important advantages of using NHPs as model for inhalation studies.

RESULTS

We demonstrate that deposition in the respiratory tract is not only a function of aerosol size but also the technique of administration influences the biological activity and site of aerosol deposition. Finally, we observe an influence of a region of pathogen deposition in the respiratory tract on the development of the pathophysiological effect in NHPs.

CONCLUSION

The wide range of methods used for the delivery of pathogento NHP respiratory airways is associated with varying doses and deposition profiles in the airways.

Nebulizers

Nebulizers generate aerosols from liquid-based solutions and suspensions. Nebulizers are particularly well suited to delivering larger doses of medication than is practical with inhalers and are used with a broad range of liquid formulations. When the same drug is available in liquid or inhaler form, nebulizers are applicable for use with patients who will not or cannot reliably use a pressurized metered-dosed inhaler (pMDI) or dry powder inhaler (DPI) due to poor lung function, hand-breath coordination, cognitive abilities (e.g., infants, elderly) or device preference. In a nebulizer, liquid medication is placed in a reservoir and fed to an aerosol generator to produce the droplets. A series of tubes and channels direct the aerosol to the patient via an interface such as mouthpiece, mask, tent, nasal prongs or artificial airway. All nebulizers contain these basic parts, although the technology and design used can vary widely and can result in significant difference in ergonomics, directions for use, and performance. While many types of nebulizers have been described, the three categories of modern clinical nebulizers include: (1) pneumatic jet nebulizers (JN); (2) ultrasonic nebulizers (USN); and (3) vibrating mesh nebulizers (VMN). Nebulizers are also described in terms of their reservoir size. Small volume nebulizers (SVNs), most commonly used for medical aerosol therapy, can hold 5 to 20 mL of medication and may be jet, ultrasonic, or mesh nebulizers. Large volume nebulizers, typically jet or ultrasonic nebulizers, hold up to 200 mL and may be used for either bland aerosol therapy or continuous drug administration.

Influence of mesh nebulizer characteristics on aerosol delivery in non-human primates

Non-Human Primates (NHPs) are particularly relevant for preclinical studies during the development of inhaled biologics. However, aerosol inhalation in NHPs is difficult to evaluate due to a low lung deposition fraction and high variability. The objective of this study was to evaluate the influence of mesh nebulizer parameters to improve lung deposition in macaques. We developed a humidified heated and ventilated anatomical 3D printed macaque model of the upper respiratory tract to reduce experiments with animals. The model was compared to in vivo deposition using 2D planar scintigraphy imaging in NHPs and demonstrated good predictivity. Next, the anatomical model was used to evaluate the position of the nebulizer on the mask, the aerosol particle size and the aerosol flow rate on the lung deposition. We showed that placing the mesh-nebulizer in the upper part of the mask and in proximal position to the NHP improved lung delivery prediction. The lower the aerosol size and the lower the aerosol flow rate, the better the predicted aerosol deposition. In particular, for 4.3 ± 0.1 µm in terms of volume mean diameter, we obtained 5.6 % ± 0.2 % % vs 19.2 % ± 2.5 % deposition in the lung model for an aerosol flow rate of 0.4 mL/min vs 0.03 mL/min and achieved 16 % of the nebulizer charge deposited in the lungs of macaques. Despite the improvement of lung deposition efficiency in macaques, its variability remained high (6-21 %).

Efficacy and Safety of Dry Powder Antibiotics: A Narrative Review

The use of inhaled antibiotics was initially almost exclusively confined to patients with cystic fibrosis (CF). However, it has been extended in recent decades to patients with non-CF bronchiectasis or chronic obstructive pulmonary disease who present with chronic bronchial infection by potentially pathogenic microorganisms. Inhaled antibiotics reach high concentrations in the area of infection, which enhances their effect and enables their long-term administration to defeat the most resistant infections, while minimizing possible adverse effects. New formulations of inhaled dry powder antibiotics have been developed, providing, among other advantages, faster preparation and administration of the drug, as well as avoiding the requirement to clean nebulization equipment. In this review, we analyze the advantages and disadvantages of the different types of devices that allow the inhalation of antibiotics, especially dry powder inhalers. We describe their general characteristics, the different inhalers on the market and the proper way to use them. We analyze the factors that influence the way in which the dry powder drug reaches the lower airways, as well as aspects of microbiological effectiveness and risks of resistance development. We review the scientific evidence on the use of colistin and tobramycin with this type of device, both in patients with CF and with non-CF bronchiectasis. Finally, we discuss the literature on the development of new dry powder antibiotics.

A four-part guide to lung immunology: Invasion, inflammation, immunity, and intervention

Lungs are important respiratory organs primarily involved in gas exchange. Lungs interact directly with the environment and their primary function is affected by several inflammatory responses caused by allergens, inflammatory mediators, and pathogens, eventually leading to disease. The immune architecture of the lung consists of an extensive network of innate immune cells, which induce adaptive immune responses based on the nature of the pathogen(s). The balance of immune responses is critical for maintaining immune homeostasis in the lung. Infection by pathogens and physical or genetic dysregulation of immune homeostasis result in inflammatory diseases. These responses culminate in the production of a plethora of cytokines such as TSLP, IL-9, IL-25, and IL-33, which have been implicated in the pathogenesis of several inflammatory and autoimmune diseases. Shifting the balance of Th1, Th2, Th9, and Th17 responses have been the targets of therapeutic interventions in the treatment of these diseases. Here, we have briefly reviewed the innate and adaptive i3mmune responses in the lung. Genetic and environmental factors, and infection are the major causes of dysregulation of various functions of the lung. We have elaborated on the impact of inflammatory and infectious diseases, advances in therapies, and drug delivery devices on this critical organ. Finally, we have provided a comprehensive compilation of different inflammatory and infectious diseases of the lungs and commented on the pros and cons of different inhalation devices for the management of lung diseases. The review is intended to provide a summary of the immunology of the lung, with an emphasis on drug and device development.

Repurposing mucosal delivery devices for live attenuated tuberculosis vaccines

Tuberculosis (TB) remains one of the most lethal infectious diseases globally. The only TB vaccine approved by the World Health Organization, Bacille Calmette-Guérin (BCG), protects children against severe and disseminated TB but provides limited protection against pulmonary TB in adults. Although several vaccine candidates have been developed to prevent TB and are undergoing preclinical and clinical testing, BCG remains the gold standard. Currently, BCG is administered as an intradermal injection, particularly in TB endemic countries. However, mounting evidence from experimental animal and human studies indicates that delivering BCG directly into the lungs provides enhanced immune responses and greater protection against TB. Inhalation therapy using handheld delivery devices is used for some diseases and allows the delivery of drugs or vaccines directly into the human respiratory tract. Whether this mode of delivery could also be applicable for live attenuated bacterial vaccines such as BCG or other TB vaccine candidates remains unknown. Here we discuss how two existing inhalation devices, the mucosal atomization device (MAD) syringe, used for influenza vaccines, and the Respimat® Soft Mist™ inhaler, used for chronic obstructive pulmonary disease (COPD) therapy, could be repurposed for mucosal delivery of live attenuated TB vaccines. We also outline the challenges and outstanding research questions that will require further investigations to ensure usefulness of respiratory delivery devices that are cost-effective and accessible to lower- and middle-income TB endemic countries.

Indian Guidelines on Nebulization Therapy

Inhalational therapy, today, happens to be the mainstay of treatment in obstructive airway diseases (OADs), such as asthma, chronic obstructive pulmonary disease (COPD), and is also in the present, used in a variety of other pulmonary and even non-pulmonary disorders. Hand-held inhalation devices may often be difficult to use, particularly for children, elderly, debilitated or distressed patients. Nebulization therapy emerges as a good option in these cases besides being useful in the home care, emergency room and critical care settings. With so many advancements taking place in nebulizer technology; availability of a plethora of drug formulations for its use, and the widening scope of this therapy; medical practitioners, respiratory therapists, and other health care personnel face the challenge of choosing appropriate inhalation devices and drug formulations, besides their rational application and use in different clinical situations. Adequate maintenance of nebulizer equipment including their disinfection and storage are the other relevant issues requiring guidance. Injudicious and improper use of nebulizers and their poor maintenance can sometimes lead to serious health hazards, nosocomial infections, transmission of infection, and other adverse outcomes. Thus, it is imperative to have a proper national guideline on nebulization practices to bridge the knowledge gaps amongst various health care personnel involved in this practice. It will also serve as an educational and scientific resource for healthcare professionals, as well as promote future research by identifying neglected and ignored areas in this field. Such comprehensive guidelines on this subject have not been available in the country and the only available proper international guidelines were released in 1997 which have not been updated for a noticeably long period of over two decades, though many changes and advancements have taken place in this technology in the recent past. Much of nebulization practices in the present may not be evidence-based and even some of these, the way they are currently used, may be ineffective or even harmful. Recognizing the knowledge deficit and paucity of guidelines on the usage of nebulizers in various settings such as inpatient, out-patient, emergency room, critical care, and domiciliary use in India in a wide variety of indications to standardize nebulization practices and to address many other related issues; National College of Chest Physicians (India), commissioned a National task force consisting of eminent experts in the field of Pulmonary Medicine from different backgrounds and different parts of the country to review the available evidence from the medical literature on the scientific principles and clinical practices of nebulization therapy and to formulate evidence-based guidelines on it. The guideline is based on all possible literature that could be explored with the best available evidence and incorporating expert opinions. To support the guideline with high-quality evidence, a systematic search of the electronic databases was performed to identify the relevant studies, position papers, consensus reports, and recommendations published. Rating of the level of the quality of evidence and the strength of recommendation was done using the GRADE system. Six topics were identified, each given to one group of experts comprising of advisors, chairpersons, convenor and members, and such six groups (A-F) were formed and the consensus recommendations of each group was included as a section in the guidelines (Sections I to VI). The topics included were: A. Introduction, basic principles and technical aspects of nebulization, types of equipment, their choice, use, and maintenance B. Nebulization therapy in obstructive airway diseases C. Nebulization therapy in the intensive care unit D. Use of various drugs (other than bronchodilators and inhaled corticosteroids) by nebulized route and miscellaneous uses of nebulization therapy E. Domiciliary/Home/Maintenance nebulization therapy; public & health care workers education, and F. Nebulization therapy in COVID-19 pandemic and in patients of other contagious viral respiratory infections (included later considering the crisis created due to COVID-19 pandemic). Various issues in different sections have been discussed in the form of questions, followed by point-wise evidence statements based on the existing knowledge, and recommendations have been formulated.

Development and evaluation of nanoemulsion and microsuspension formulations of curcuminoids for lung delivery with a novel approach to understanding the aerosol performance of nanoparticles

Extensive research has demonstrated the potential effectiveness of curcumin against various diseases, including asthma and cancers. However, few studies have used liquid-based vehicles in the preparation of curcumin formulations. Therefore, the current study proposed the use of nanoemulsion and microsuspension formulations to prepare nebulised curcuminoid for lung delivery. Furthermore, this work expressed a new approach to understanding the aerosol performance of nanoparticles compared to microsuspension formulations. The genotoxicity of the formulations was also assessed. Curcuminoid nanoemulsion formulations were prepared in three concentrations (100, 250 and 500 µg/ml) using limonene and oleic acid as oil phases, while microsuspension solutions were prepared by suspending curcuminoid particles in isotonic solution (saline solution) of 0.02% Tween 80. The average fine particle fraction (FPF) and mass median aerodynamic diameter (MMAD) of the nebulised microsuspension formulations ranged from 26% and 7.1 µm to 40% and 5.7 µm, for 1000 µg/ml and 100 µg/ml respectively. In a comparison of the low and high drug concentrations of the nebulised nanoemulsion, the average FPF and MMAD of the nebulised nanoemulsion formulations prepared with limonene oil ranged from 50% and 4.6 µm to 45% and 5.6 µm, respectively; whereas the FPF and MMAD of the nebulised nanoemulsion prepared with oleic acid oil ranged from 46% and 4.9 µm to 44% and 5.6 µm, respectively. The aerosol performance of the microsuspension formulations were concentration dependent, while the nanoemulsion formulations did not appear to be dependent on the curcuminoids concentration. The performance and genotoxicity results of the formulations suggest the suitability of these preparations for further inhalation studies in animals.

Japanese guidelines for childhood asthma 2017

The Japanese Guideline for the Diagnosis and Treatment of Allergic Diseases 2017 (JAGL 2017) includes a minor revision of the Japanese Pediatric Guideline for the Treatment and Management of Asthma 2012 (JPGL 2012) by the Japanese Society of Pediatric Allergy and Clinical Immunology. The section on child asthma in JAGL 2017 provides information on how to diagnose asthma between infancy and adolescence (0-15 years of age). It makes recommendations for best practices in the management of childhood asthma, including management of acute exacerbations and non-pharmacological and pharmacological management. This guideline will be of interest to non-specialist physicians involved in the care of children with asthma. JAGL differs from the Global Initiative for Asthma Guideline in that JAGL emphasizes diagnosis and early intervention of children with asthma at <2 years or 2-5 years of age. The first choice of treatment depends on the severity and frequency of symptoms. Pharmacological management, including step-up or step-down of drugs used for long-term management based on the status of asthma control levels, is easy to understand; thus, this guideline is suitable for the routine medical care of children with asthma. JAGL also recommends using a control test in children, so that the physician aims for complete control by avoiding exacerbating factors and appropriately using anti-inflammatory drugs (for example, inhaled corticosteroids and leukotriene receptor antagonists).

The function and performance of aqueous aerosol devices for inhalation therapy

OBJECTIVES

In this review paper, we explore the interaction between the functioning mechanism of different nebulizers and the physicochemical properties of the formulations for several types of devices, namely jet, ultrasonic and vibrating-mesh nebulizers; colliding and extruded jets; electrohydrodynamic mechanism; surface acoustic wave microfluidic atomization; and capillary aerosol generation.

KEY FINDINGS

Nebulization is the transformation of bulk liquids into droplets. For inhalation therapy, nebulizers are widely used to aerosolize aqueous systems, such as solutions and suspensions. The interaction between the functioning mechanism of different nebulizers and the physicochemical properties of the formulations plays a significant role in the performance of aerosol generation appropriate for pulmonary delivery. Certain types of nebulizers have consistently presented temperature increase during the nebulization event. Therefore, careful consideration should be given when evaluating thermo-labile drugs, such as protein therapeutics. We also present the general approaches for characterization of nebulizer formulations.

SUMMARY

In conclusion, the interplay between the dosage form (i.e. aqueous systems) and the specific type of device for aerosol generation determines the effectiveness of drug delivery in nebulization therapies, thus requiring extensive understanding and characterization.

Japanese Guideline for Childhood Asthma 2014

The Japanese Guideline for the Diagnosis and Treatment of Allergic Diseases 2013 (JAGL 2013) describes childhood asthma after the Japanese Pediatric Guideline for the Treatment and Management of Asthma 2012 (JPGL 2012) by the Japanese Society of Pediatric Allergy and Clinical Immunology. JAGL 2013 provides information on diagnosis by age group from infancy to puberty (0-15 years of age), treatment for acute exacerbations, long-term management by anti-inflammatory drugs, daily life guidance, and patient education to allow non-specialist physicians to refer to this guideline for routine medical treatment. JAGL differs from the Global Initiative for Asthma Guideline (GINA) in that JAGL emphasizes early diagnosis and intervention at <2 years and 2-5 years of age. A management method, including step-up or step-down of long-term management drugs based on the status of asthma control levels, as in JAGL, is easy to understand, and thus the Guideline is suitable as a frame of reference for routine medical treatment. JAGL has also introduced treatment and management using a control test on children, recommending that the physician aim at complete control by avoiding exacerbation factors and by appropriate use of anti-inflammatory drugs.

Faraday instability-based micro droplet ejection for inhalation drug delivery

We report here the technology and the underlying science of a new device for inhalation (pulmonary) drug delivery which is capable of fulfilling needs unmet by current commercial devices. The core of the new device is a centimeter-size clog-free silicon-based ultrasonic nozzle with multiple Fourier horns in resonance at megahertz (MHz) frequency. The dramatic resonance effect among the multiple horns and high growth rate of the MHz Faraday waves excited on a medicinal liquid layer together facilitate ejection of monodisperse droplets of desirable size range (2-5 µm) at low electrical drive power (<1.0 W). The small nozzle requiring low drive power has enabled realization of a pocket-size (8.6 × 5.6 × 1.5 cm³) ultrasonic nebulizer. A variety of common pulmonary drugs have been nebulized using the pocket-size unit with desirable aerosol sizes and output rate. These results clearly provide proof-of-principle for the new device and confirm its potential for commercialization.

The effects of suspension particle size on the performance of air-jet, ultrasonic and vibrating-mesh nebulisers

Using latex microspheres as model suspensions, the influence of suspension particle size (1, 4.5 and 10 μm) on the properties of aerosols produced using Pari LC Sprint (air-jet), Polygreen (ultrasonic), Aeroneb Pro (actively vibrating-mesh) and Omron MicroAir NE-U22 (passively vibrating-mesh) nebulisers was investigated. The performance of the Pari nebuliser was independent of latex spheres particle size. For both Polygreen and Aeroneb Pro nebulizers, total aerosol output increased when the size of latex spheres increased, with highest fine particle fraction (FPF) values being recorded. However, following nebulisation of 1 or 4.5 μm suspensions with the Polygreen device, no particles were detected in the aerosols deposited in a two-stage impinger, suggesting that the aerosols generated from this device consisted mainly of the continuous phase while the dispersed microspheres were excluded and remained in the nebuliser. The Omron nebuliser efficiently nebulised the 1 μm latex spheres, with high output rate and no particle aggregation. However, this device functioned inefficiently when delivering 4.5 or 10 μm suspensions, which was attributed to the mild vibrations of its mesh and/or the blockage of the mesh apertures by the microspheres. The Aeroneb Pro fragmented latex spheres into smaller particles, but uncontrolled aggregation occurred upon nebulisation. This study has shown that the design of the nebuliser influenced the aerosol properties using latex spheres as model suspensions. Moreover, for the recently marketed mesh nebulisers, the performance of the Aeroneb Pro device was less dependent on particle size of the suspension compared with the Omron MicroAir nebuliser.

Alternatives to conventional suspensions for pulmonary drug delivery by nebulisers: a review

This review discusses the reports of alternative dosage forms to suspension formulations of hydrophobic drugs for nebulisers. Suspensions for nebulisers, although widely used over recent years, have several limitations which have led to pharmaceutical researchers looking for alternative, better performing preparations. Particular attention has been directed towards the use of nanoparticles as carriers of hydrophobic active ingredients. Several nanoformulations have been prepared and compared in vitro and/or in vivo with the corresponding microsuspension formulation. It is also clear that future studies in this field should address the parallel important aspects of safety and economical aspects of nanoparticualte formulations.

Evaluation of a nanoemulsion-based formulation for respiratory delivery of budesonide by nebulizers

The aim of this work was to evaluate the in vitro performance of a nebulized nanoemulsion formulation which had been optimised previously. To do so, a transparent nanoemulsion preparation containing 1.5 mg/ml of budesonide was prepared and diluted to achieve concentrations of 250 and 500 μg/ml budesonide. The in vitro characteristics of the diluted nanoemulsions were then compared with the commercially available suspension of budesonide (Pulmicort Respules®) when nebulized using a jet and a vibrating mesh nebulizer. A smaller MMAD with improved aerosol output was observed in the nanoemulsion preparations compared with the corresponding suspension formulations indicating an improved in vitro performance for the nanoemulsion-based preparations.

Ultrasonic nebulization platforms for pulmonary drug delivery

IMPORTANCE OF THE FIELD

Since the 1950s, ultrasonic nebulizers have played an important role in pulmonary drug delivery. As the process in which aerosol droplets are generated is independent and does not require breath-actuation, ultrasonic nebulizers, in principle, offer the potential for instantaneously fine-tuning the dose administered to the specific requirements of a patient, taking into account the patient's breathing pattern, physiological profile and disease state. Nevertheless, owing to the difficulties and limitations associated with conventional designs and technologies, ultrasonic nebulizers have never been widely adopted, and have in recent years been in a state of decline.

AREAS COVERED IN THIS REVIEW

An overview is provided on the advances in new miniature ultrasonic nebulization platforms in which large increases in lung dose efficiency have been reported.

WHAT THE READER WILL GAIN

In addition to a discussion of the underlying mechanisms governing ultrasonic nebulization, in which there appears to be widely differing views, the advantages and shortcomings of conventional ultrasonic nebulization technology are reviewed and advanced state-of-the-art technologies that have been developed recently are discussed.

TAKE HOME MESSAGE

Recent advances in ultrasonic nebulization technology demonstrate significant potential for the development of smart, portable inhalation therapy platforms for the future. Nevertheless, there remain considerable challenges that need to be addressed before such personalized delivery systems can be realized. These have to be addressed across the spectrum from fundamental physics through to in vivo device testing and dealing with the relevant regulatory framework.

Five-day course of budesonide inhalation suspension is as effective as oral prednisolone in the treatment of mild to severe acute asthma exacerbations in adults

BACKGROUND

Limited evidence is available on the use of budesonide inhalation suspension (BIS) for the treatment of mild to severe acute asthma exacerbations (AAE) in adults in an inpatient setting. This study was conducted to evaluate the efficacy of a five-day course of BIS compared with oral prednisolone (OP) in the management of adults with AAE.

METHODS

A retrospective study examined the response of 28 patients hospitalized with mild to severe acute asthma exacerbation from January 2003 to December 2003. These patients, who were steroid free ≥ 1 yr, were administered a five-day course of BIS (2 × 2 mg bid) or OP (2 × 15 mg bid). PEF, FEV(1) and asthma symptom scores were recorded daily.

RESULTS

The BIS (n = 13) and OP (n = 15) treatment groups were comparable at baseline for demographic characteristics and prebronchodilator (fenoterol) FEV(1) of 52.4% predicted normal value and 54.6% predicted normal value, respectively. Mean change of morning PEF was 152 L/min during BIS treatment and 130 L/min for OP treatment; the mean changes of morning forced expiratory volumes in 1 s (FEV(1)) were 1.0 and 0.7 L, respectively. The mean change in daytime symptom scores were -1.6 and -1.3 in the BIS and the OP groups, respectively. Improvements in PEF, FEV(1) and daytime symptom scores were significantly different between baseline and after treatment in each treatment group (p < 0.05). However, improvements in both BIS and OP groups were similar.

CONCLUSION

Budesonide inhalation suspension may be an alternative treatment of acute asthma exacerbation in adults who are at risk for systemic corticosteroids.

Evaluation of patient-reported outcomes and quality of life with the I-neb AAD system in patients with chronic obstructive pulmonary disease

BACKGROUND

The I-neb Adaptive Aerosol Delivery (AAD) System is a novel portable mesh nebulizer that provides patient feedback regarding adherence to prescribed treatment and compliance with the correct use of the device.

METHODS

This multicenter study was composed of 98 patients aged 53-80 years with Chronic Obstructive Pulmonary Disease (COPD). The primary variables were ease of use and satisfaction, which were assessed after 3 months of use of the I-neb AAD System (assessed at visit 2) and after 3 months of use of the patient's previous nebulizer system (assessed at visit 1) using matched questions from pre- and poststudy questionnaires. Quality of life was also assessed at visits 1 and 2 using the validated Chronic Respiratory Questionnaire (CRQ), which consists of dyspnea, emotional function, fatigue, and mastery domains. Differences in the distribution of responses between the pre- and poststudy ease of use and satisfaction questions were analyzed using the Marginal Homogeneity test. Differences in mean CRQ scores between the pre- and poststudy assessments were analyzed using the Wilcoxon Signed-Rank test.

RESULTS

Patient responses on the ease of use and satisfaction questions significantly (p < or = 0.001) favored the I-neb AAD System compared with the patient's previous nebulizer system. In addition, significant (p < or = 0.015) improvements in the CRQ dimensions of dyspnea and fatigue were reported with the I-neb AAD System compared with the patients' previous nebulizer systems.

CONCLUSIONS

The results from this study demonstrated that patients were more satisfied with the I-neb AAD System and found it easier to use than their previous nebulizer systems. In addition, the I-neb AAD System significantly improved dyspnea and fatigue compared with the patients' previous nebulizer systems, which may reflect improved adherence or more correct use of the nebulizer system with the I-neb AAD System.

Evaluation of supercritical fluid engineered budesonide powder for respiratory delivery using nebulisers

Objectives

Currently, suspensions prepared from micronised drug substances are the only delivery system marketed for nebulisation of steroids, and reported inconsistent or low bioavailability arising from their use provides a rationale for researching alternative formulations. Supercritical fluid processing of drug substances to obtain respirable-sized particles has been used over the last decade to formulate dry powder inhalers. We aimed thus to process budesonide powder to improve its deposition characteristics.

Methods

In an attempt to overcome the limitations of nebuliser suspensions when prepared from micronised drug particles, budesonide powder was processed using a supercritical fluid based process and suspended using Tween 80 as a surfactant to provide an aqueous nebuliser formulation. The in-vitro characteristics of the emitted dose on nebulisation for the prepared suspension were then compared to a commercially available suspension formulation of budesonide using a jet and a vibrating mesh nebuliser.

Key findings

The results showed a significant improvement of the in-vitro deposition properties of the suspension containing supercritical fluid engineered budesonide particles.

Conclusions

The results indicated the benefit of such materials compared with traditionally micronised drug powders.

Inhospital management of COPD exacerbations: a systematic review of the literature with regard to adherence to international guidelines

Rationale Chronic obstructive pulmonary disease (COPD) exacerbations are a leading cause of hospitalization. Suboptimal inhospital management is expected to lead to more frequent exacerbations and recurrent hospital admission, and is associated with increased mortality. Aims To explore inhospital management of COPD and to compare the results with recommendations from international guidelines. Methods A literature search was carried out for relevant articles published 2000-2009 in the databases Medline, Cochrane Library, Cumulative Index for Nursing and Allied Health Literature and Invert. In addition, the reference lists of the selected articles were examined. Main inclusion criteria were as follows: COPD, exacerbation, hospitalization, description of inpatient management, and clinical trials. Assessment and treatment strategies in different studies were analysed and compared with American Thoracic Society-European Respiratory Society and Global Initiative for Chronic Obstructive Lung Disease guidelines. Outcomes were analysed. Results Seven eligible studies were selected. Non-pharmacological treatment was infrequently explored. When compared with international guidelines, diagnostic assessment and therapy were suboptimal, especially non-pharmacological treatment. Respiratory physicians were more likely to perform recommended interventions than non-respiratory physicians. Conclusions Adherence to international guidelines is low for inhospital management of COPD exacerbations, especially in terms of non-pharmacological treatment. Further investigation is recommended to explore strategies like care pathways that improve performance of recommended interventions.

Pulmonary Drug Delivery System for inhalation therapy in mechanically ventilated patients

The Pulmonary Drug Delivery System (PDDS) Clinical represents a newer generation of electronic nebulizers that employ a vibrating mesh or aperture plate to generate an aerosol. The PDDS Clinical is designed for aerosol therapy in patients receiving mechanical ventilation. The components of the device include a control module that is connected to the nebulizer/reservoir unit by a cable. The nebulizer contains Aerogen's OnQ aerosol generator. A pressure sensor monitors the pressure in the inspiratory limb of the ventilator circuit and provides feedback to the control module. Based on the feedback from the pressure sensor, aerosol generation occurs only during a specific part of the respiratory cycle. In bench models, the PDDS Clinical has high efficiency for aerosol delivery both on and off the ventilator, with a lower respiratory tract delivery of 50-70% of the nominal dose. Currently, the PDDS Clinical is being evaluated for the treatment of ventilator-associated pneumonia with aerosolized amikacin, an aminoglycoside antibiotic. Preliminary studies in patients with ventilator-associated pneumonia found that the administration of amikacin via PDDS reduced the need for concomitant intravenous antibiotics; however, more definitive clinical studies are needed. The PDDS Clinical delivers a high percentage of the nominal dose to the lower respiratory tract, and is well suited for inhalation therapy in mechanically ventilated patients.

[Nebulized corticosteroids and pediatricians: results of the NUAGES survey]

INTRODUCTION

The aim of the study was to analyze the data of the NUAGES survey (a survey on the practice of nebulization in France), concerning the prescriptions of nebulized steroids from 514 pediatricians.

MATERIAL AND METHODS

The reason why nebulization was chosen as a delivery route, the diseases motivating the prescription, the age of the patients, the kind of drug used, and the prescription and device modalities were studied.

RESULTS

Efficacy in treating various respiratory diseases was the main reason cited for using nebulization, in particular severe persistent asthma (76%). Pediatricians prescribed nebulization mainly to infants (60%). The most frequently used drug was budesonide suspension (89%), but the intravenous route for steroids (18%) and drug admixtures (62%) were also proposed by nebulization. A specific prescription for the nebulizer was given in 75% of the cases, with the type of interface to use specified in 66%.

DISCUSSION

Pediatricians consider that nebulization is well adapted to young children. Although the proper steroid is usually chosen, unfortunately, it is often prescribed with other drugs, with 1 prescription out of 4 not following the recommendations. Prescription of the device is not optimal and may compromise the efficacy of the treatment.

CONCLUSION

Nebulization is a potential mode of delivery for steroids that is difficult to prescribe and warrants improved pediatrician training.

The customised electronic nebuliser: a new category of liquid aerosol drug delivery systems

Inhalation of aerosols is the preferred route of administration of pharmaceutical compounds to the lungs when treating various respiratory diseases. Inhaled antibiotics, hormones, peptides and proteins are potential candidates for direct targeting to the site of action, thus minimising systemic absorption, dilution and undesired side effects, as much lower doses (as low as a fiftieth) are sufficient to achieve a similar therapeutic effect, compared with oral administration. A quick relief from the symptoms and a good tolerance are the main advantages of aerosol therapy. A new class of electronic delivery device is now starting to enter the market. The eFlow electronic nebuliser (PARI GmbH, Germany) provides improved portability and, in some instances, cuts treatment time to only a fraction of what has been experienced with current nebulised therapy. Drug formulations and the device can be mutually adapted and matched for optimal characteristics to meet the desired therapeutic target. Reformulation of known and proven compounds in a liquid format are commercially attractive as they present a relatively low development risk for potential drug candidates and, thus, have become a preferred pathway for the development of new inhalation products.

Budesonide inhalation suspension for the treatment of asthma in infants and children

On the basis of the well recognised role of inflammation in the pathogenesis of asthma, anti-inflammatory therapy, in the form of inhaled corticosteroids, has become the mainstay of treatment in patients with persistent asthma. Budesonide inhalation suspension (BIS) is a nonhalogenated corticosteroid with a high ratio of local anti-inflammatory activity to systemic activity. Furthermore, BIS is approved in >70 countries for the maintenance treatment of bronchial asthma in both paediatric and adult patients (approval is limited to paediatric patients in the US and France).Randomised, double-blind, placebo-controlled trials conducted in >1000 children have demonstrated the efficacy of BIS in children with persistent asthma of varying degrees of severity. In children frequently hospitalised with uncontrolled asthma, initiation of BIS therapy can reduce the need for emergency intervention. Moreover, limited data suggest that BIS is effective for the treatment of acute exacerbations of asthma in children and may reduce the need for short courses of oral corticosteroids.BIS is well tolerated in children, with an adverse event profile similar to that of placebo, and no clinically relevant changes in adrenal function have been demonstrated during the course of short- and long-term (1-year) studies. Small but statistically significant reductions in growth velocity have been demonstrated with BIS over 1 year of treatment. However, available evidence suggests that growth effects are transient in children receiving budesonide and that these children eventually achieve full adult height.

In VitroEstimations ofIn VivoJet Nebulizer Efficiency Using Actual and Simulated Tidal Breathing Patterns

In vivo aerosol delivery efficiency was estimated in vitro for two jet nebulizers using a breath monitor (Breathe!; Pari GmbH, Germany) and breath simulator (COMPAS; Pari GmbH) to reproduce subject tidal breathing patterns. The AeroEclipse (Trudell Medical International, Canada), a breath-actuated nebulizer, and the LC Star (Pari GmbH), a breath-enhanced nebulizer, were filled with levalbuterol HCl solution (Sepracor, USA) and operated with compressed O(2) at 8 lpm. Tidal breathing patterns of 20 adult subjects were digitally recorded with the Breathe! Breath Monitor. Subjects then breathed tidally from each nebulizer separately for 1 minute and to nebulizer dryness. Levalbuterol aerosol collected on filters placed between the nebulizer and mouth was chemically assayed to determine the inspired mass (IM), wasted mass (WM) and total emitted mass (TM). Measurements were repeated using the COMPAS Breath Simulator to simulate each subject's tidal breathing pattern. IM, WM, and TM measurements using actual versus simulated tidal breathing were highly comparable for each nebulizer, except the IM (p < 0.05) from LC Star measured at nebulizer dryness. Breath simulation was an inaccurate tool for estimating the time to nebulizer dryness as simulated measurements to nebulizer dryness took significantly longer than measurements preformed with actual tidal breathing (p < 0.001). While breath simulation provides an accurate in vitro tool for estimating in vivo aerosol delivery, it should not completely replace in vivo measurements until inherent limitations in simulator operation can be overcome to provide a more clinically realistic simulation.

The role of nebulized inhaled corticosteroid therapy in adult patients with asthma and chronic obstructive pulmonary disease

Conventional metered-dose inhalers and dry powder inhalers are used by most adult patients with asthma and chronic obstructive pulmonary disease who receive inhaled corticosteroid therapy. There are circumstances, however, in which nebulized inhaled corticosteroid delivery may provide greater clinical benefit to these patients. This review discusses the efficacy and safety of nebulized inhaled corticosteroid therapy in adult patients with asthma or chronic obstructive pulmonary disease for whom nebulized therapy may be preferable.

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.

Use of inhaler devices in pediatric asthma

Inhalation is the preferred route for asthma therapy, since it offers a rapid onset of drug action, requires smaller doses, and reduces systemic effects compared with other routes of administration. Unfortunately, inhalation devices are frequently used in an empirical manner rather than on evidence-based awareness.A wide variety of nebulizers are available. Conventional jet nebulizers are highly inefficient, as much of the aerosol is wasted during exhalation. However, incorporating an extra open vent into the system has considerably increased the amount of drug that patients receive. Breath-assisted open vent nebulizers limit the loss of aerosol during exhalation, but are dependent on the patient's inspiratory flow. Ultrasonic nebulizers produce a high mass output and have a short nebulization time, but are inefficient for delivering suspensions or viscous solutions. Adaptive aerosol delivery devices release a precise dose that is tailored to the individual patient's breathing pattern. Nebulizers have several drawbacks, and their use should be limited to patients who cannot correctly manage other devices.Pressurized metered-dose inhalers (pMDI) are practical, cheap and multidose. However, there are several problems with their use. Breath-actuated MDI are easy to use and can be activated by very low flow. However, young children may not be able to use them efficiently. Dry powder inhalers (DPI) are portable and easy to use. They are indicated either for rescue bronchodilator therapy or for regular treatment with inhaled corticosteroids and long-acting bronchodilators. The use of spacers reduces oropharyngeal deposition and improves drug delivery to the lung. Spacers do not require patient coordination, but some general rules must be followed for their optimal use.Thus, the choice of a delivery device mainly depends on the age of the patient, the drug to be administered and the condition to be treated. Proper education is also essential when prescribing an inhalation device.

Importance of drug delivery system in steroid aerosol therapy via nebulizer

Aim of our study was to evaluate if the type of nebulizer can influence the effects of steroid aerosol therapy. We considered 27 asthmatics allergic to grasses with FEV1<80% of the predictive value or methacholine PD20 FEV1<750 mcg. The patients were divided into three groups in relation to the type of nebulizer they used and treated 9 weeks by aerosol therapy with beclomethasone dipropionate bid (800 mcg). Respect to the values recorded at the beginning and at the end of the therapy we found different variations of spirometric indeces and PD20 values among the three groups. We can conclude that the type of nebulizer influences steroid aerosol therapy and, particularly, jet nebulizers seem more efficient than ultrasonic nebulizers.

Budesonide inhalation suspension: a nebulized corticosteroid for persistent asthma

Guidelines for managing asthma in pediatric patients published by the American Academy of Allergy, Asthma, and Immunology and the American Academy of Pediatrics recommend the use of inhaled corticosteroids for the management of persistent asthma in infants and young children. When these guidelines were published, pressurized metered-dose inhalers and dry-powder inhalers were the only delivery devices available for inhaled corticosteroids in the United States. These devices can be difficult for young children to use correctly. Furthermore, no inhaled corticosteroid was approved in the United States for the treatment of children younger than 4 years. Budesonide inhalation suspension (Pulmicort Respules; AstraZeneca LP, Wilmington, Del) was developed to meet the medication delivery needs of infants and young children with persistent asthma. Pulmicort Respules is the first inhaled corticosteroid approved for administration by means of a nebulizer and the only inhaled corticosteroid approved in the United States for infants as young as 12 months. Budesonide has been studied extensively worldwide. In the United States the tolerability and efficacy of budesonide inhalation suspension were confirmed in 3 placebo-controlled multicenter trials. These studies demonstrated that both once- and twice-daily dosing of budesonide inhalation suspension (0.25-1 mg) improved pulmonary function and ameliorated asthma symptoms in infants and young children with persistent asthma. Budesonide inhalation suspension was well tolerated, and the incidences of reported adverse events were similar among patients in the budesonide, placebo, and conventional asthma therapy groups. This article reviews the results of these studies, as well as the pharmacokinetics, pharmacodynamics, and clinical use of budesonide inhalation suspension.

Budesonide inhalation suspension: a review of its use in infants, children and adults with inflammatory respiratory disorders

Budesonide, a topically active corticosteroid, has a broad spectrum of clinically significant local anti-inflammatory effects in patients with inflammatory lung diseases including persistent asthma. In infants and young children with persistent asthma, day- and night-time symptom scores, and the number of days in which beta2-agonist bronchodilators were required, were significantly lower during randomised, double-blind treatment with budesonide inhalation suspension 0.5 to 2 mg/day than placebo in 3 multicentre trials. Significantly fewer children discontinued therapy with budesonide inhalation suspension than with placebo because of worsening asthma symptoms in a study that included children who were receiving inhaled corticosteroids at baseline. Recent evidence indicates that budesonide inhalation suspension is significantly more effective than nebulised sodium cromoglycate in improving control of asthma in young children with persistent asthma. At a dosage of 2 mg/day, budesonide inhalation suspension significantly reduced the number of asthma exacerbations and requirements for systemic corticosteroids in preschool children with severe persistent asthma. In children with acute asthma or wheezing, the preparation was as effective as, or more effective than oral prednisolone in improving symptoms. In children with croup, single 2 or 4mg dosages of budesonide inhalation suspension were significantly more effective than placebo and as effective as oral dexamethasone 0.6 mg/kg or nebulised L-epinephrine (adrenaline) 4mg in alleviating croup symptoms and preventing or reducing the duration of hospitalisation. Early initiation of therapy with budesonide inhalation suspension 1 mg/day appears to reduce the need for mechanical ventilation and decrease overall corticosteroid usage in preterm very low birthweight infants at risk for chronic lung disease. In adults with persistent asthma, budesonide inhalation suspension < or =8 mg/day has been compared with inhaled budesonide 1.6 mg/day and fluticasone propionate 2 mg/day administered by metered dose inhaler. Greater improvements in asthma control occurred in patients during treatment with budesonide inhalation suspension than with budesonide via metered dose inhaler, whereas fluticasone propionate produced greater increases in morning peak expiratory flow rates than nebulised budesonide. Several small studies suggest that the preparation has an oral corticosteroid-sparing effect in adults with persistent asthma and that it may be as effective as oral corticosteroids during acute exacerbations of asthma or chronic obstructive pulmonary disease. The frequency of adverse events was similar in children receiving budesonide inhalation suspension 0.25 to 2 mg/day or placebo in 12-week studies. During treatment with budesonide inhalation suspension 0.5 to 1 mg/day in 3 nonblind 52-week studies, growth velocity in children was generally unaffected; however, a small but statistically significant decrease in growth velocity was detected in children who were not using inhaled corticosteroids prior to the introduction of budesonide inhalation suspension. Hypothalamic-pituitary-adrenal axis function was not affected by short (12 weeks) or long (52 weeks) term treatment with nebulised budesonide. In conclusion, budesonide inhalation suspension is the most widely available nebulised corticosteroid, and in the US is the only inhaled corticosteroid indicated in children aged > or =1 year with persistent asthma. The preparation is suitable for use in infants, children and adults with persistent asthma and in infants and children with croup.

Validation of a new breathing simulator generating and measuring inhaled aerosol with adult breathing patterns

The use of breathing simulators for the in vitro determination of the inhaled mass of drug from nebulizers has become widely accepted. Their use is, however, based on the assumption that there is a correlation between the in vitro and in vivo inhaled mass of drug. The aim of the study was therefore to investigate whether a new breathing simulator--the MIMIC Breathing Emulator (Medic-Aid Limited, Bognor Regis, UK)--could accurately emulate the in vivo inhaled mass of budesonide suspension for nebulization. Eight adult healthy subjects were included. Each subject inhaled for 2 min from a Spira Module 1 jet nebulizer (Respiratory Care Center, Hämeenlinna, Finland), charged with 1.0 mg of budesonide suspension for nebulization (0.5 mg mL-1, 2 mL suspension, AstraZeneca, Sweden) and supplied with an inhaled mass filter between the nebulizer and the subject. The breathing patterns were recorded during the nebulization and simulated in vitro at two different experimental sites (simulations A and B) with the breathing simulator. With the patients breathing through the filters (in vivo test), inhaled mass of budesonide averaged 103.6 micrograms. The two in vitro experiments using the simulator revealed similar results with in vitro simulation A equal to 101.0 micrograms and simulation B 99.1 micrograms. There were no statistically significant differences between the in vivo results and those of in vitro simulation A. Results were significantly different for simulation B (p = 0.032) although the difference was less than 4.5%. These data indicate that the breathing simulator can be used to accurately simulate sine waveforms, human breathing patterns, and the in vitro and in vivo inhaled mass of budesonide suspension for nebulization.

Breath-synchronized nebulization diminishes the impact of patient-device interfaces (face mask or mouthpiece) on the inhaled mass of nebulized budesonide

The choice of patient-device interface (face mask or mouthpiece) influences the inhaled mass and the lung deposition of nebulized drugs. The use of a mouthpiece has been shown to double the lung deposition compared with use of a face mask. We have determined the inhaled mass of budesonide using a jet nebulizer with mouthpiece in either a constant output or breath-synchronized mode in children. We have also determined the inhaled mass when the jet nebulizer is used with a nonsealing face mask in a constant output mode. The study was a 1-day, randomized, crossover, single-center study involving 158 asthmatic children (age range 5.1-15.7 years). Nebulized budesonide was administered in three single nominal doses of 1.0 mg by means of a jet nebulizer. The inhaled mass of budesonide was defined as the amount of drug deposited on filters positioned between the nebulizer and the mouthpiece or face mask. The mean inhaled mass of budesonide from different age groups ranged from 1 7.1% to 21.6% of the nominal dose with breath-synchronized nebulization with a mouthpiece. With constant output nebulization with a mouthpiece, the mean inhaled mass ranged from 8.9% to 12.2%, and with a nonsealed face mask the mean inhaled mass ranged from 5.0% to 6.9%. For children using jet nebulizers with mouthpiece, breath-synchronized nebulization appears to be superior to conventional constant output nebulization. The use of jet nebulizers with nonsealing face masks should be avoided.

Once-daily inhaled corticosteroids in children with asthma: nebulisation

Current guidelines on the management of childhood asthma have emphasised the important preventive role of inhaled corticosteroids, which should be used at the lowest possible doses that are compatible with good disease control. However, some children do not respond to inhaled corticosteroids, the most common reasons for which are inability to use conventional hand-held inhalers (plus spacers and face masks) effectively or lack of cooperation with them, particularly among infants and young children. In these patients, nebulisers have proved effective in administering corticosteroids, and this form of delivery is often preferred by both the children and their parents, despite their longer administration times (commonly around 10 minutes). Compliance with these devices may therefore be better than with a conventional pressurised metered-dose inhaler plus spacer and face mask. Recent studies with nebulised budesonide have demonstrated that once-daily administration is as effective in maintaining control of asthma symptoms in children as the usual twice-daily administration. In children with moderately severe persistent asthma, the improvement provided by once-daily nebulised doses of 1.0 mg budesonide has been found to be equivalent to that with twice-daily doses of 0.25 or 0.5 mg, indicating that once-daily therapy is an effective option that can be considered in many patients. In view of the time-consuming nature of nebuliser administration, reduction of the frequency of corticosteroid administration from twice to once daily may be useful in simplifying the treatment programme and improving compliance with it. This may be beneficial in reducing under-utilisation of inhaled corticosteroids in children with asthma and improving long term control of the disease.