Impact of Flow Restrictors on Aerosol Delivery of the Respimat® Soft Mist Inhaler.

IF 3 Q2 RESPIRATORY SYSTEM

Pulmonary Therapy Pub Date : 2025-09-10 DOI:10.1007/s41030-025-00312-3

Moritz Fleischhauer, Kai Berkenfeld, David Stadermann, Sitaram Velaga, Igor Gonda, Peter Langguth, Herbert Wachtel

{"title":"Impact of Flow Restrictors on Aerosol Delivery of the Respimat® Soft Mist Inhaler.","authors":"Moritz Fleischhauer, Kai Berkenfeld, David Stadermann, Sitaram Velaga, Igor Gonda, Peter Langguth, Herbert Wachtel","doi":"10.1007/s41030-025-00312-3","DOIUrl":null,"url":null,"abstract":"Introduction: The modification of an inhaler's air flow resistance influences a patient's inhalation flow profile, thereby affecting the exit velocity of an aerosol leaving the Respimat® mouthpiece. A slower inhalation maneuver results in reduced plume velocity and thus a decreased oropharyngeal deposition due to reduced impaction. This could not only lead to fewer unwanted side effects associated with inhaled therapies, but also enhance lung deposition.Methods: Device prototypes with different air flow resistances were designed using custom-made inserts that can be clipped into the Respimat mouthpiece. The consequences on aerosol characteristics, as well as on in vitro deposition, were analyzed. Computational fluid dynamics simulations contributed to a better understanding of the modified aerodynamic conditions.Results: Different insert geometries resulted in modified device resistances. However, an increased flow resistance does not necessarily result in an improved in vitro performance. The flow restrictors critically determine aerosol characteristics such as plume velocity and spray pattern, thereby altering in vitro deposition patterns. Quantitative data on mouth-throat deposition and aerosol characteristics are reported.Conclusions: Integrating flow restrictors into the Respimat mouthpiece offers a promising approach to enhance patient centricity by promoting slower inhalation, thereby reducing the likelihood of suboptimal use. The use of a porous insert acting as a diffuser demonstrated minimal impact on internal airflow dynamics and in vitro deposition, suggesting that such designs can support correct inhalation technique without compromising aerosol performance. By minimizing the influence of patient-dependent factors, this strategy may help standardize the inhalation process and improve therapeutic outcomes. Video Abstract available for this article. Video Abstract (MP4 85313 KB).","PeriodicalId":20919,"journal":{"name":"Pulmonary Therapy","volume":" ","pages":""},"PeriodicalIF":3.0000,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Pulmonary Therapy","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1007/s41030-025-00312-3","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"RESPIRATORY SYSTEM","Score":null,"Total":0}

引用次数: 0

Abstract

Introduction: The modification of an inhaler's air flow resistance influences a patient's inhalation flow profile, thereby affecting the exit velocity of an aerosol leaving the Respimat® mouthpiece. A slower inhalation maneuver results in reduced plume velocity and thus a decreased oropharyngeal deposition due to reduced impaction. This could not only lead to fewer unwanted side effects associated with inhaled therapies, but also enhance lung deposition.

Methods: Device prototypes with different air flow resistances were designed using custom-made inserts that can be clipped into the Respimat mouthpiece. The consequences on aerosol characteristics, as well as on in vitro deposition, were analyzed. Computational fluid dynamics simulations contributed to a better understanding of the modified aerodynamic conditions.

Results: Different insert geometries resulted in modified device resistances. However, an increased flow resistance does not necessarily result in an improved in vitro performance. The flow restrictors critically determine aerosol characteristics such as plume velocity and spray pattern, thereby altering in vitro deposition patterns. Quantitative data on mouth-throat deposition and aerosol characteristics are reported.

Conclusions: Integrating flow restrictors into the Respimat mouthpiece offers a promising approach to enhance patient centricity by promoting slower inhalation, thereby reducing the likelihood of suboptimal use. The use of a porous insert acting as a diffuser demonstrated minimal impact on internal airflow dynamics and in vitro deposition, suggesting that such designs can support correct inhalation technique without compromising aerosol performance. By minimizing the influence of patient-dependent factors, this strategy may help standardize the inhalation process and improve therapeutic outcomes. Video Abstract available for this article. Video Abstract (MP4 85313 KB).

查看原文本刊更多论文

气流限制器对Respimat®软雾吸入器气溶胶输送的影响

简介：吸入器气流阻力的改变会影响患者的吸入气流，从而影响气溶胶离开Respimat®吸口的出口速度。一个较慢的吸入机动结果减少羽流速度，因此减少口咽沉积由于减少嵌塞。这不仅可以减少与吸入疗法相关的不良副作用，还可以增强肺沉积。方法：使用定制的可夹入呼吸口的插入物设计具有不同气流阻力的器械原型。分析了对气溶胶特性的影响以及对体外沉积的影响。计算流体动力学模拟有助于更好地理解改进后的空气动力学条件。结果：不同的插入物几何形状导致器械阻力的改变。然而，增加的流动阻力并不一定导致体外性能的改善。气流限制器严格地决定了气溶胶特性，如羽流速度和喷雾模式，从而改变了体外沉积模式。报告了口喉沉积和气溶胶特征的定量数据。结论：将流量限制器集成到呼吸口中是一种很有希望的方法，可以通过促进缓慢吸入来增强患者的中心性，从而减少次优使用的可能性。多孔插入物作为扩散器的使用对内部气流动力学和体外沉积的影响最小，这表明这种设计可以支持正确的吸入技术，而不会影响气溶胶的性能。通过最大限度地减少患者依赖因素的影响，该策略可能有助于规范吸入过程并改善治疗结果。视频摘要可用于本文。视频摘要（MP4 85313 KB）。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Pulmonary Therapy Medicine-Pulmonary and Respiratory Medicine

CiteScore

5.20

自引率

3.30%

发文量

审稿时长

6 weeks

期刊介绍： Aims and Scope Pulmonary Therapy is an international, open access, peer-reviewed (single-blind), and rapid publication journal. The scope of the journal is broad and will consider all scientifically sound research from pre-clinical, clinical (all phases), observational, real-world, and health outcomes research around the use of pulmonary therapies, devices, and surgical techniques. Areas of focus include, but are not limited to: asthma; chronic obstructive pulmonary disease; idiopathic pulmonary fibrosis; pulmonary hypertension; cystic fibrosis; lung cancer; respiratory tract disorders; allergic rhinitis and other respiratory allergies; influenza, pneumococcal infection, respiratory syncytial virus and other respiratory infections; and inhalers and other device therapies. The journal is of interest to a broad audience of pharmaceutical and healthcare professionals and publishes original research, reviews, case reports/series, trial protocols and short communications such as commentaries and editorials. Pulmonary Therapy will consider all scientifically sound research be it positive, confirmatory or negative data. Submissions are welcomed whether they relate to an international and/or a country-specific audience, something that is crucially important when researchers are trying to target more specific patient populations. This inclusive approach allows the journal to assist in the dissemination of quality research, which may be considered of insufficient interest by other journals. Rapid Publication The journal’s publication timelines aim for a rapid peer review of 2 weeks. If an article is accepted it will be published 3–4 weeks from acceptance. The rapid timelines are achieved through the combination of a dedicated in-house editorial team, who manage article workflow, and an extensive Editorial and Advisory Board who assist with peer review. This allows the journal to support the rapid dissemination of research, whilst still providing robust peer review. Combined with the journal’s open access model this allows for the rapid, efficient communication of the latest research and reviews, fostering the advancement of pulmonary therapies. Open Access All articles published by Pulmonary Therapy are open access. Personal Service The journal’s dedicated in-house editorial team offer a personal “concierge service” meaning authors will always have an editorial contact able to update them on the status of their manuscript. The editorial team check all manuscripts to ensure that articles conform to the most recent COPE, GPP and ICMJE publishing guidelines. This supports the publication of ethically sound and transparent research. Digital Features and Plain Language Summaries Pulmonary Therapy offers a range of additional features designed to increase the visibility, readership and educational value of the journal’s content. Each article is accompanied by key summary points, giving a time-efficient overview of the content to a wide readership. Articles may be accompanied by plain language summaries to assist readers who have some knowledge of, but not in-depth expertise in, the area to understand the scientific content and overall implications of the article. The journal also provides the option to include various types of digital features including animated abstracts, video abstracts, slide decks, audio slides, instructional videos, infographics, podcasts and animations. All additional features are peer reviewed to the same high standard as the article itself. If you consider that your paper would benefit from the inclusion of a digital feature, please let us know. Our editorial team are able to create high-quality slide decks and infographics in-house, and video abstracts through our partner Research Square, and would be happy to assist in any way we can. For further information about digital features, please contact the journal editor (see ‘Contact the Journal’ for email address), and see the ‘Guidelines for digital features and plain language summaries’ document under ‘Submission guidelines’. For examples of digital features please visit our showcase page https://springerhealthcare.com/expertise/publishing-digital-features/ Publication Fees Upon acceptance of an article, authors will be required to pay the mandatory Rapid Service Fee of €4500/ $5100/ £3650. The journal will consider fee discounts and waivers for developing countries and this is decided on a case by case basis. Peer Review Process Upon submission, manuscripts are assessed by the editorial team to ensure they fit within the aims and scope of the journal and are also checked for plagiarism. All suitable submissions are then subject to a comprehensive single-blind peer review. Reviewers are selected based on their relevant expertise and publication history in the subject area. The journal has an extensive pool of editorial and advisory board members who have been selected to assist with peer review based on the afore-mentioned criteria. At least two extensive reviews are required to make the editorial decision, with the exception of some article types such as Commentaries, Editorials, and Letters which are generally reviewed by one member of the Editorial Board. Where reviewer recommendations are conflicted, the editorial board will be contacted for further advice and a presiding decision. Manuscripts are then either accepted, rejected or authors are required to make major or minor revisions (both reviewer comments and editorial comments may need to be addressed). Once a revised manuscript is re-submitted, it is assessed along with the responses to reviewer comments and if it has been adequately revised it will be accepted for publication. Accepted manuscripts are then copyedited and typeset by the production team before online publication. Appeals against decisions following peer review are considered on a case-by-case basis and should be sent to the journal editor. Preprints We encourage posting of preprints of primary research manuscripts on preprint servers, authors’ or institutional websites, and open communications between researchers whether on community preprint servers or preprint commenting platforms. Posting of preprints is not considered prior publication and will not jeopardize consideration in our journals. Authors should disclose details of preprint posting during the submission process or at any other point during consideration in one of our journals. Once the manuscript is published, it is the author’s responsibility to ensure that the preprint record is updated with a publication reference, including the DOI and a URL link to the published version of the article on the journal website. Please follow the link for further information on preprint sharing: https://www.springer.com/gp/authors-editors/journal-author/journal-author-helpdesk/submission/1302#c16721550 Copyright Pulmonary Therapy''s content is published open access under the Creative Commons Attribution-Noncommercial License, which allows users to read, copy, distribute, and make derivative works for non-commercial purposes from the material, as long as the author of the original work is cited. The author assigns the exclusive right to any commercial use of the article to Springer. For more information about the Creative Commons Attribution-Noncommercial License, click here: http://creativecommons.org/licenses/by-nc/4.0. Contact For more information about the journal, including pre-submission enquiries, please contact christopher.vautrinot@springer.com.