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McGinn EA, Bye E, Gonzalez T, Sosa A, Bilodeaux J, Seedorf G, Smith BJ, Abman SH, Mandell EW. Antenatal Endotoxin Induces Dysanapsis in Experimental Bronchopulmonary Dysplasia. Am J Respir Cell Mol Biol 2024; 70:283-294. [PMID: 38207120 DOI: 10.1165/rcmb.2023-0157oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 01/10/2024] [Indexed: 01/13/2024] Open
Abstract
Bronchopulmonary dysplasia (BPD), the chronic lung disease of prematurity, is characterized by impaired lung development with sustained functional abnormalities due to alterations of airways and the distal lung. Although clinical studies have shown striking associations between antenatal stress and BPD, little is known about the underlying pathogenetic mechanisms. Whether dysanapsis, the concept of discordant growth of the airways and parenchyma, contributes to late respiratory disease as a result of antenatal stress is unknown. We hypothesized that antenatal endotoxin (ETX) impairs juvenile lung function as a result of altered central airway and distal lung structure, suggesting the presence of dysanapsis in this preclinical BPD model. Fetal rats were exposed to intraamniotic ETX (10 μg) or saline solution (control) 2 days before term. We performed extensive structural and functional evaluation of the proximal airways and distal lung in 2-week-old rats. Distal lung structure was quantified by stereology. Conducting airway diameters were measured using micro-computed tomography. Lung function was assessed during invasive ventilation to quantify baseline mechanics, response to methacholine challenge, and spirometry. ETX-exposed pups exhibited distal lung simplification, decreased alveolar surface area, and decreased parenchyma-airway attachments. ETX-exposed pups exhibited decreased tracheal and second- and third-generation airway diameters. ETX increased respiratory system resistance and decreased lung compliance at baseline. Only Newtonian resistance, specific to large airways, exhibited increased methacholine reactivity in ETX-exposed pups compared with controls. ETX-exposed pups had a decreased ratio of FEV in 0.1 second to FVC and a normal FEV in 0.1 second, paralleling the clinical definition of dysanapsis. Antenatal ETX causes abnormalities of the central airways and distal lung growth, suggesting that dysanapsis contributes to abnormal lung function in juvenile rats.
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Affiliation(s)
- Elizabeth A McGinn
- Pediatric Heart Lung Center, Department of Pediatrics
- Department of Pediatric Critical Care Medicine
| | - Elisa Bye
- Pediatric Heart Lung Center, Department of Pediatrics
| | | | - Alexander Sosa
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Jill Bilodeaux
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | | | - Bradford J Smith
- Pediatric Heart Lung Center, Department of Pediatrics
- Department of Pediatric Pulmonary and Sleep Medicine, and
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Steven H Abman
- Pediatric Heart Lung Center, Department of Pediatrics
- Department of Pediatric Pulmonary and Sleep Medicine, and
| | - Erica W Mandell
- Pediatric Heart Lung Center, Department of Pediatrics
- Department of Neonatology, University of Colorado School of Medicine, Aurora, Colorado; and
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2
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Smith EF, Bradshaw TK, Urs RC, Evans DJ, Hemy NR, Hall GL, Wilson AC, Simpson SJ. Oscillometry and spirometry are not interchangeable when assessing the bronchodilator response in children and young adults born preterm. Pediatr Pulmonol 2023; 58:3122-3132. [PMID: 37539845 PMCID: PMC10947568 DOI: 10.1002/ppul.26632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/20/2023] [Accepted: 07/24/2023] [Indexed: 08/05/2023]
Abstract
INTRODUCTION The European Respiratory Society Oscillometry Taskforce identified that clinical correlates of bronchodilator responses are needed to advance oscillometry in clinical practice. The understanding of bronchodilator-induced oscillometry changes in preterm lung disease is poor. Here we describe a comparison of bronchodilator assessments performed using oscillometry and spirometry in a population born very preterm and explore the relationship between bronchodilator-induced changes in respiratory function and clinical outcomes. METHODS Participants aged 6-23 born ≤32 (N = 288; 132 with bronchopulmonary dysplasia) and ≥37 weeks' gestation (N = 76, term-born controls) performed spirometry and oscillometry. A significant bronchodilator response (BDR) to 400 μg salbutamol was classified according to published criteria. RESULTS A BDR was identified in 30.9% (n = 85) of preterm-born individuals via spirometry and/or oscillometry, with poor agreement between spirometry and oscillometry definitions (k = 0.26; 95% confidence interval [CI] 0.18-0.40, p < .001). Those born preterm with a BDR by oscillometry but not spirometry had increased wheeze (33% vs. 11%, p = .010) and baseline resistance (Rrs5 z-score mean difference (MD) = 0.86, 95% CI 0.07-1.65, p = .025), but similar baseline spirometry to the group without a BDR (forced expiratory volume in 1 s [FEV1 ] z-score MD = -0.01, 95% CI -0.66 to 0.68, p > .999). Oscillometry was more feasible than spirometry (95% success rate vs. 85% (FEV1 ), 69% (forced vital capacity) success rate, p < .001), however being born preterm did not affect test feasibility. CONCLUSION In the preterm population, oscillometry is a feasible and clinically useful supportive test to assess the airway response to inhaled salbutamol. Changes measured by oscillometry reflect related but distinct physiological changes to those measured by spirometry, and thus these tests should not be used interchangeably.
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Affiliation(s)
- Elizabeth F. Smith
- Wal‐Yan Respiratory Research Centre, Telethon Kids InstitutePerth Children's HospitalNedlandsAustralia
- Curtin School of Allied HealthFaculty of Health SciencesBentleyAustralia
| | - Tiffany K. Bradshaw
- Wal‐Yan Respiratory Research Centre, Telethon Kids InstitutePerth Children's HospitalNedlandsAustralia
| | - Rhea C. Urs
- Wal‐Yan Respiratory Research Centre, Telethon Kids InstitutePerth Children's HospitalNedlandsAustralia
- Curtin School of Allied HealthFaculty of Health SciencesBentleyAustralia
| | - Denby J. Evans
- Wal‐Yan Respiratory Research Centre, Telethon Kids InstitutePerth Children's HospitalNedlandsAustralia
- Curtin School of Allied HealthFaculty of Health SciencesBentleyAustralia
| | - Naomi R. Hemy
- Wal‐Yan Respiratory Research Centre, Telethon Kids InstitutePerth Children's HospitalNedlandsAustralia
| | - Graham L. Hall
- Wal‐Yan Respiratory Research Centre, Telethon Kids InstitutePerth Children's HospitalNedlandsAustralia
- Curtin School of Allied HealthFaculty of Health SciencesBentleyAustralia
| | - Andrew C. Wilson
- Wal‐Yan Respiratory Research Centre, Telethon Kids InstitutePerth Children's HospitalNedlandsAustralia
- Curtin School of Allied HealthFaculty of Health SciencesBentleyAustralia
- Child and Adolescent Health ServicePerth Children's HospitalNedlandsAustralia
| | - Shannon J. Simpson
- Wal‐Yan Respiratory Research Centre, Telethon Kids InstitutePerth Children's HospitalNedlandsAustralia
- Curtin School of Allied HealthFaculty of Health SciencesBentleyAustralia
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3
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McGinn EA, Mandell EW, Smith BJ, Duke JW, Bush A, Abman SH. Dysanapsis as a Determinant of Lung Function in Development and Disease. Am J Respir Crit Care Med 2023; 208:956-963. [PMID: 37677135 PMCID: PMC10870865 DOI: 10.1164/rccm.202306-1120pp] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 09/07/2023] [Indexed: 09/09/2023] Open
Affiliation(s)
| | - Erica W. Mandell
- Pediatric Heart Lung Center, Department of Pediatrics
- Department of Neonatology
| | - Bradford J. Smith
- Pediatric Heart Lung Center, Department of Pediatrics
- Department of Pediatric Pulmonary and Sleep Medicine, and
- Department of Bioengineering, Anschutz School of Medicine, University of Colorado–Denver, Aurora, Colorado
| | - Joseph W. Duke
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona; and
| | - Andrew Bush
- Center for Pediatrics and Child Health, Imperial College of Medicine, London, United Kingdom
| | - Steven H. Abman
- Pediatric Heart Lung Center, Department of Pediatrics
- Department of Pediatric Pulmonary and Sleep Medicine, and
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4
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Hubbard CD, Bates ML, Lovering AT, Duke JW. Consequences of Preterm Birth: Knowns, Unknowns, and Barriers to Advancing Cardiopulmonary Health. Integr Comp Biol 2023; 63:693-704. [PMID: 37253617 PMCID: PMC10503472 DOI: 10.1093/icb/icad045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 05/24/2023] [Accepted: 05/25/2023] [Indexed: 06/01/2023] Open
Abstract
Preterm birth occurs in 10% of all live births and creates challenges to neonatal life, which persist into adulthood. Significant previous work has been undertaken to characterize and understand the respiratory and cardiovascular sequelae of preterm birth, which are present in adulthood, i.e., "late" outcomes. However, many gaps in knowledge are still present and there are several challenges that will make filling these gaps difficult. In this perspective we discuss the obstacles of studying adults born preterm, including (1) the need for invasive (direct) measures of physiologic function; (2) the need for multistate, multinational, and diverse cohorts; (3) lack of socialized medicine in the United States; (4) need for detailed and better-organized birth records; and (5) transfer of neonatal and pediatric knowledge to adult care physicians. We conclude with a discussion on the "future" of studying preterm birth in regards to what may happen to these individuals as they approach middle and older age and how the improvements in perinatal and postnatal care may be changing the phenotypes observed in adults born preterm on or after the year 2000.
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Affiliation(s)
- Colin D Hubbard
- Department of Biological Sciences, Northern Arizona University, 86011, Flagstaff, AZ, USA
| | - Melissa L Bates
- Department of Health and Human Physiology, University of Iowa, 52242, Iowa City, IA, USA
- Department of Internal Medicine and Pediatrics, University of Iowa, 52242, Iowa City, IA, USA
| | - Andrew T Lovering
- Department of Human Physiology, University of Oregon, 97403, Eugene, OR, USA
| | - Joseph W Duke
- Department of Biological Sciences, Northern Arizona University, 86011, Flagstaff, AZ, USA
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5
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Rigotti C, Zannin E, Veneroni C, Ventura ML, Dellacà RL. Oscillatory Mechanics Response to Inhaled Bronchodilators in Very Preterm Infants: A Retrospective Study. J Pediatr 2022; 251:149-155. [PMID: 35944717 DOI: 10.1016/j.jpeds.2022.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 07/27/2022] [Accepted: 08/02/2022] [Indexed: 10/15/2022]
Abstract
OBJECTIVES To identify short-term repeatability of forced oscillation technique (FOT) measurement of lung function, assess the lung function response to bronchodilators (BDs) by FOT, and prove the concept that only some very preterm infants manifest a change in lung mechanics in response to BD. STUDY DESIGN We retrospectively analyzed respiratory system resistance and respiratory system reactance measured by FOT (Fabian HFOi). The measurement short-term repeatability was assessed in 43 patients on 60 occasions; BD responsiveness was assessed using a different data set, including 38 measurements in 18 infants. The coefficient of repeatability was calculated as twice the SD of differences between measurements performed 15 minutes apart. We assessed BD responsiveness by measuring respiratory system resistance and respiratory system reactance before and 15 minutes after administering 200 mcg/kg of nebulized salbutamol. A positive response was defined as an improvement in respiratory system resistance or respiratory system reactance greater than the identified coefficient of repeatability. RESULTS The coefficient of repeatability was 7.5 cmH2O∗s/L (21%) for respiratory system resistance and 6.3 cmH2O∗s/L (21%) for respiratory system reactance. On average, respiratory system resistance did not change significantly following BD administration, though respiratory system reactance increased significantly (from -32.0 [-50.2, -24.4] to -27.9 [-38.1, -22.0] cmH2O∗s/L, P < .001). Changes in respiratory system resistance or respiratory system reactance after BD were greater than the identified coefficient of repeatability in 8 infants (44%) on 13 (34%) occasions. CONCLUSIONS We identified a threshold to assess BD responsiveness by FOT in preterm infants. We speculate that FOT could be used to assess and personalize treatment with BD.
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Affiliation(s)
- Camilla Rigotti
- Neonatal Intensive Care Unit, Fondazione Monza e Brianza per il Bambino e la sua Mamma (MBBM), Monza, Italy
| | - Emanuela Zannin
- Neonatal Intensive Care Unit, Fondazione Monza e Brianza per il Bambino e la sua Mamma (MBBM), Monza, Italy
| | - Chiara Veneroni
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy
| | - Maria Luisa Ventura
- Neonatal Intensive Care Unit, Fondazione Monza e Brianza per il Bambino e la sua Mamma (MBBM), Monza, Italy
| | - Raffaele L Dellacà
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy
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6
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Lifelong Lung Sequelae of Prematurity. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19095273. [PMID: 35564667 PMCID: PMC9104309 DOI: 10.3390/ijerph19095273] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 04/22/2022] [Accepted: 04/24/2022] [Indexed: 11/29/2022]
Abstract
The clinical, functional, and structural pattern of chronic lung disease of prematurity has changed enormously in last years, mirroring a better perinatal management and an increasing lung immaturity with the survival of increasingly premature infants. Respiratory symptoms and lung function impairment related to prematurity seem to improve over time, but premature birth increases the likelihood of lung function impairment in late childhood, predisposing to chronic obstructive pulmonary disease (COPD). It is mandatory to identify those individuals born premature who are at risk for developing long-term lung disease through a better awareness of physicians, the use of standardized CT imaging scores, and a more comprehensive periodic lung function evaluation. The aim of this narrative review was to provide a systematic approach to lifelong respiratory symptoms, lung function impairment, and lung structural anomalies in order to better understand the specific role of prematurity on lung health.
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7
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Kaminsky DA, Simpson SJ, Berger KI, Calverley P, de Melo PL, Dandurand R, Dellacà RL, Farah CS, Farré R, Hall GL, Ioan I, Irvin CG, Kaczka DW, King GG, Kurosawa H, Lombardi E, Maksym GN, Marchal F, Oostveen E, Oppenheimer BW, Robinson PD, van den Berge M, Thamrin C. Clinical significance and applications of oscillometry. Eur Respir Rev 2022; 31:31/163/210208. [PMID: 35140105 PMCID: PMC9488764 DOI: 10.1183/16000617.0208-2021] [Citation(s) in RCA: 56] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 10/29/2021] [Indexed: 12/28/2022] Open
Abstract
Recently, “Technical standards for respiratory oscillometry” was published, which reviewed the physiological basis of oscillometric measures and detailed the technical factors related to equipment and test performance, quality assurance and reporting of results. Here we present a review of the clinical significance and applications of oscillometry. We briefly review the physiological principles of oscillometry and the basics of oscillometry interpretation, and then describe what is currently known about oscillometry in its role as a sensitive measure of airway resistance, bronchodilator responsiveness and bronchial challenge testing, and response to medical therapy, particularly in asthma and COPD. The technique may have unique advantages in situations where spirometry and other lung function tests are not suitable, such as in infants, neuromuscular disease, sleep apnoea and critical care. Other potential applications include detection of bronchiolitis obliterans, vocal cord dysfunction and the effects of environmental exposures. However, despite great promise as a useful clinical tool, we identify a number of areas in which more evidence of clinical utility is needed before oscillometry becomes routinely used for diagnosing or monitoring respiratory disease. This paper provides a current review of the interpretation, clinical significance and application of oscillometry in respiratory medicine, with special emphasis on limitations of evidence and suggestions for future research.https://bit.ly/3GQPViA
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Affiliation(s)
- David A Kaminsky
- Dept of Medicine, Pulmonary and Critical Care Medicine, University of Vermont, Larner College of Medicine, Burlington, VT, USA.,These authors have contributed equally to this manuscript
| | - Shannon J Simpson
- Children's Lung Health, Telethon Kids Institute, School of Allied Health, Curtin University, Perth, Australia.,These authors have contributed equally to this manuscript
| | - Kenneth I Berger
- Division of Pulmonary, Critical Care, and Sleep Medicine, NYU School of Medicine and André Cournand Pulmonary Physiology Laboratory, Belleuve Hospital, New York, NY, USA
| | - Peter Calverley
- Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK
| | - Pedro L de Melo
- Dept of Physiology, Biomedical Instrumentation Laboratory, Institute of Biology and Faculty of Engineering, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ronald Dandurand
- Lakeshore General Hospital, Pointe-Claire, QC, Canada.,Montreal Chest Institute, Meakins-Christie Labs, Oscillometry Unit of the Centre for Innovative Medicine, McGill University Health Centre and Research Institute, and McGill University, Montreal, QC, Canada
| | - Raffaele L Dellacà
- Dipartimento di Elettronica, Informazione e Bioingegneria - DEIB, Politecnico di Milano University, Milan, Italy
| | - Claude S Farah
- Dept of Respiratory Medicine, Concord Repatriation General Hospital, Sydney, Australia
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona-IDIBAPS, Barcelona, Spain.,CIBER de Enfermedades Respiratorias, Madrid, Spain
| | - Graham L Hall
- Children's Lung Health, Telethon Kids Institute, School of Allied Health, Curtin University, Perth, Australia
| | - Iulia Ioan
- Dept of Paediatric Lung Function Testing, Children's Hospital, Vandoeuvre-lès-Nancy, France.,EA 3450 DevAH - Laboratory of Physiology, Faculty of Medicine, University of Lorraine, Vandoeuvre-lès-Nancy, France
| | - Charles G Irvin
- Dept of Medicine, Pulmonary and Critical Care Medicine, University of Vermont, Larner College of Medicine, Burlington, VT, USA
| | - David W Kaczka
- Depts of Anaesthesia, Biomedical Engineering and Radiology, University of Iowa, Iowa City, IA, USA
| | - Gregory G King
- Dept of Respiratory Medicine and Airway Physiology and Imaging Group, Royal North Shore Hospital, St Leonards, Australia.,Woolcock Institute of Medical Research, The University of Sydney, Sydney, Australia
| | - Hajime Kurosawa
- Dept of Occupational Health, Tohoku University School of Medicine, Sendai, Japan
| | - Enrico Lombardi
- Paediatric Pulmonary Unit, Meyer Paediatric University Hospital, Florence, Italy
| | - Geoffrey N Maksym
- School of Biomedical Engineering, Dalhousie University, Halifax, NS, Canada
| | - François Marchal
- Dept of Paediatric Lung Function Testing, Children's Hospital, Vandoeuvre-lès-Nancy, France.,EA 3450 DevAH - Laboratory of Physiology, Faculty of Medicine, University of Lorraine, Vandoeuvre-lès-Nancy, France
| | - Ellie Oostveen
- Dept of Respiratory Medicine, Antwerp University Hospital and University of Antwerp, Belgium
| | - Beno W Oppenheimer
- Division of Pulmonary, Critical Care, and Sleep Medicine, NYU School of Medicine and André Cournand Pulmonary Physiology Laboratory, Belleuve Hospital, New York, NY, USA
| | - Paul D Robinson
- Woolcock Institute of Medical Research, Children's Hospital at Westmead, Sydney, Australia
| | - Maarten van den Berge
- Dept of Pulmonary Diseases, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Cindy Thamrin
- Woolcock Institute of Medical Research, The University of Sydney, Sydney, Australia
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8
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Zannin E, Rigotti C, Neumann RP, Dellacà RL, Schulzke S, Ventura ML. Oscillatory mechanics at 36 weeks post-menstrual age as markers of lung disease in preterm infants: a cohort study. Eur Respir J 2022; 59:13993003.03023-2021. [PMID: 35236725 DOI: 10.1183/13993003.03023-2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 02/09/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Emanuela Zannin
- UO Neonatologia e Terapia Intensiva Neonatale, Fondazione Monza e Brianza per il Bambino e la sua Mamma (MBBM), Monza, Italy .,TechRes Lab, Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano University, Milan, Italy
| | - Camilla Rigotti
- UO Neonatologia e Terapia Intensiva Neonatale, Fondazione Monza e Brianza per il Bambino e la sua Mamma (MBBM), Monza, Italy
| | - Roland P Neumann
- Department of Neonatology, University Children's Hospital Basel UKBB, University of Basel, Basel, Switzerland
| | - Raffaele L Dellacà
- TechRes Lab, Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano University, Milan, Italy
| | - Sven Schulzke
- Department of Neonatology, University Children's Hospital Basel UKBB, University of Basel, Basel, Switzerland
| | - Maria Luisa Ventura
- UO Neonatologia e Terapia Intensiva Neonatale, Fondazione Monza e Brianza per il Bambino e la sua Mamma (MBBM), Monza, Italy
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9
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Duke JW, Lewandowski AJ, Abman SH, Lovering AT. Physiological aspects of cardiopulmonary dysanapsis on exercise in adults born preterm. J Physiol 2022; 600:463-482. [PMID: 34961925 PMCID: PMC9036864 DOI: 10.1113/jp281848] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 12/03/2021] [Indexed: 02/03/2023] Open
Abstract
Progressive improvements in perinatal care and respiratory management of preterm infants have resulted in increased survival of newborns of extremely low gestational age over the past few decades. However, the incidence of bronchopulmonary dysplasia, the chronic lung disease after preterm birth, has not changed. Studies of the long-term follow-up of adults born preterm have shown persistent abnormalities of respiratory, cardiovascular and cardiopulmonary function, possibly leading to a lower exercise capacity. The underlying causes of these abnormalities are incompletely known, but we hypothesize that dysanapsis, i.e. discordant growth and development, in the respiratory and cardiovascular systems is a central structural feature that leads to a lower exercise capacity in young adults born preterm than those born at term. We discuss how the hypothesized system dysanapsis underscores the observed respiratory, cardiovascular and cardiopulmonary limitations. Specifically, adults born preterm have: (1) normal lung volumes but smaller airways, which causes expiratory airflow limitation and abnormal respiratory mechanics but without impacts on pulmonary gas exchange efficiency; (2) normal total cardiac size but smaller cardiac chambers; and (3) in some cases, evidence of pulmonary hypertension, particularly during exercise, suggesting a reduced pulmonary vascular capacity despite reduced cardiac output. We speculate that these underlying developmental abnormalities may accelerate the normal age-associated decline in exercise capacity, via an accelerated decline in respiratory, cardiovascular and cardiopulmonary function. Finally, we suggest areas of future research, especially the need for longitudinal and interventional studies from infancy into adulthood to better understand how preterm birth alters exercise capacity across the lifespan.
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Affiliation(s)
- Joseph W. Duke
- Northern Arizona University, Department of Biological Sciences, Flagstaff, AZ, USA
| | - Adam J. Lewandowski
- University of Oxford, Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, UK
| | - Steven H. Abman
- University of Colorado Anschutz School of Medicine, Department of Pediatrics, Aurora, CO, USA,Pediatric Heart Lung Center, Children’s Hospital Colorado, Aurora, CO, USA
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10
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Dahl MJ, Veneroni C, Lavizzari A, Bowen S, Emerson H, Rebentisch A, Dawson E, Summers K, Pettet L, Wang Z, Null DM, Yoder BA, Dellacà RL, Albertine KH. Early extubation to noninvasive respiratory support of former preterm lambs improves long-term respiratory outcomes. Am J Physiol Lung Cell Mol Physiol 2021; 321:L248-L262. [PMID: 34009031 DOI: 10.1152/ajplung.00051.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Invasive mechanical ventilation (IMV) and exposure to oxygen-rich gas during early postnatal life are contributing factors for long-term pulmonary morbidities faced by survivors of preterm birth and bronchopulmonary dysplasia. The duration of IMV that leads to long-term pulmonary morbidities is unknown. We compared two durations of IMV (3 h vs. 6 days) during the first 6-7 days of postnatal life in preterm lambs to test the hypothesis that minimizing the duration of IMV will improve long-term respiratory system mechanics and structural outcomes later in life. Moderately preterm (∼85% gestation) lambs were supported by IMV for either 3 h or 6 days before weaning from all respiratory support to become former preterm lambs. Respiratory system mechanics and airway reactivity were assessed monthly from 1 to 6 mo of chronological postnatal age by the forced oscillation technique. Quantitative morphological measurements were made for smooth muscle accumulation around terminal bronchioles and indices of alveolar formation. Minimizing IMV to 3 h led to significantly better (P < 0.05) baseline respiratory system mechanics and less reactivity to methacholine in the first 3 mo of chronological age (2 mo corrected age), significantly less (P < 0.05) accumulation of smooth muscle around peripheral resistance airways (terminal bronchioles), and significantly better (P < 0.05) alveolarization at the end of 5 mo corrected age compared with continuous IMV for 6 days. We conclude that limiting the duration of IMV following preterm birth of fetal lambs leads to better respiratory system mechanics and structural outcomes later in life.
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Affiliation(s)
- Mar Janna Dahl
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Chiara Veneroni
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano University, Milan, Italy
| | - Anna Lavizzari
- U.O. di Neonatologia e Terapia Intensiva Neonatale, Department of Clinical Sciences and Community Health, University of Milan Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Sydney Bowen
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Haleigh Emerson
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Andrew Rebentisch
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Elaine Dawson
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Kyle Summers
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Luke Pettet
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Zhengming Wang
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Donald M Null
- Division of Neonatology, University of California, Davis, California
| | - Bradley A Yoder
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Raffaele L Dellacà
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano University, Milan, Italy
| | - Kurt H Albertine
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
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11
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Roy GS, Daphtary N, Johnson O, Dixon AE, Kaminsky DA, Bates JHT. Measuring the mechanical input impedance of the respiratory system with breath-driven flow oscillations. J Appl Physiol (1985) 2021; 130:1064-1071. [PMID: 33571055 DOI: 10.1152/japplphysiol.00976.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In recent years, the mechanical input impedance of the respiratory system (Zrs) determined using the technique known as oscillometry has been gaining traction as a clinical diagnostic tool to complement conventional spirometry. Nevertheless, despite currently approved oscillometry devices being relatively compact and portable, they are still too heavy and bulky to be used in an ambulatory hands-free setting, mostly because of the mass of the motor and power supply. We therefore explored the possibility of using the subject's own respiratory musculature as the power source for creating flow oscillations at the mouth. We measured reference Zrs in 8 normal volunteers by having them breathe tidally into a piston-driven oscillator powered by an external motor. We fit the measured Zrs to the single-compartment model of the respiratory system characterized by the three parameters resistance (Rrs), elastance (Ers), and inertance (Irs). We then compared these parameter values to those obtained with two commercially available mucus-clearing devices that generate oscillations when expiratory flow drives a flapper valve. The estimates of Rrs agreed mostly within ±1 cmH2O·s·L-1, which is usefully accurate for most clinical needs. Ers and Irs agreed less well because the breath-driven oscillators provided data at essentially a single frequency close to the resonant frequency of the respiratory system. Nevertheless, we conclude that perturbing respiratory airflow and pressure with a breath-driven oscillator has the potential to provide measurements of Zrs, possibly serving as the basis for a lightweight ambulatory oscillometry system.NEW & NOTEWORTHY The technique of oscillometry for measuring the mechanical input impedance of the respiratory system is gaining traction as a clinical diagnostic tool, but the portability of existing commercially available devices is limited by the size and weight of oscillator motors and power supplies. We show that impedance can be measured by oscillations in mouth pressure and flow generated by mucus-clearing devices that are powered by the subject's own respiratory flow.
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Affiliation(s)
- Gregory S Roy
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, Vermont
| | - Nirav Daphtary
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, Vermont
| | - Olivia Johnson
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, Vermont
| | - Anne E Dixon
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, Vermont
| | - David A Kaminsky
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, Vermont
| | - Jason H T Bates
- Department of Medicine, Larner College of Medicine, University of Vermont, Burlington, Vermont
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12
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Guo WL, Eli IM, Ripoll JG, Baker SE, Shepherd JRA, Wiggins CC, Welch BT, Joyner MJ, Dominelli PB. Bronchopulmonary dysplasia patients have preserved CT-measured central airway luminal area. Respir Med 2020; 170:106071. [PMID: 32843156 DOI: 10.1016/j.rmed.2020.106071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 06/16/2020] [Accepted: 06/22/2020] [Indexed: 10/24/2022]
Abstract
Bronchopulmonary dysplasia (BPD) is a condition of neonatal chronic lung disease due to disruption or dysregulation of pulmonary development. However, the pathophysiology of BPD in the larger conducting airways is not yet fully understood. The objective of our study was to determine if the area of the central airways are altered in patients with a history of BPD. We hypothesized that compared to age- and sex-matched controls, BPD patients would have decreased area of the central conducting airways. Twenty-two BPD patients (n = 10 male, n = 12 female; median age = 10 [range:1-49] yrs) and n = 22 matched controls (n = 10 male, n = 12 female; median age = 10 [range:1-48] yrs) who had undergone a chest computed tomography (CT) scan were retrospectively identified. Measurement and analysis was performed using software that reconstructs the airways into 3D. Measurements of airway area were conducted at three points based on anatomic bifurcations for each of the following structures: trachea, left main bronchus, left upper lobe, left lower lobe, right main bronchus, intermediate bronchus, and right upper lobe. The luminal area for each airway was calculated based on the averages of the three measures. Airway luminal area was not different between BPD patients and matched controls for any of the measured airways (p > 0.05). Total lung volume detected in the CT scans was not different between BPD patients and matched controls (median [range]; 2775 [522-6215] vs 2969 [851-5612] cm3, p > 0.05). Our results suggest the luminal areas of the large conducting airways in patients with BPD are not different from matched controls.
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Affiliation(s)
- Winston L Guo
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Ilhan M Eli
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Juan G Ripoll
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Sarah E Baker
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - John R A Shepherd
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Chad C Wiggins
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Brian T Welch
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Michael J Joyner
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Paolo B Dominelli
- Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada.
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13
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Haggie S, Robinson P, Selvadurai H, Fitzgerald DA. Bronchopulmonary dysplasia: A review of the pulmonary sequelae in the post-surfactant era. J Paediatr Child Health 2020; 56:680-689. [PMID: 32270551 DOI: 10.1111/jpc.14878] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/20/2020] [Accepted: 03/11/2020] [Indexed: 01/06/2023]
Abstract
We describe the respiratory complications of bronchopulmonary dysplasia (BPD) in childhood and adolescence. The pathophysiology of bronchopulmonary dysplasia has evolved in the era of modern neonatal intensive care. In this review, we aim to summarise the contemporary evidence base and describe the common respiratory morbidities related to BPD including; home oxygen therapy, rehospitalisation, asthma and exercise limitation.
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Affiliation(s)
- Stuart Haggie
- Department of Respiratory Medicine, the Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Discipline of Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Paul Robinson
- Department of Respiratory Medicine, the Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Discipline of Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Hiran Selvadurai
- Department of Respiratory Medicine, the Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Discipline of Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Dominic A Fitzgerald
- Department of Respiratory Medicine, the Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Discipline of Child and Adolescent Health, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
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14
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Salaets T, Aertgeerts M, Gie A, Vignero J, de Winter D, Regin Y, Jimenez J, Vande Velde G, Allegaert K, Deprest J, Toelen J. Preterm birth impairs postnatal lung development in the neonatal rabbit model. Respir Res 2020; 21:59. [PMID: 32085773 PMCID: PMC7035772 DOI: 10.1186/s12931-020-1321-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 02/13/2020] [Indexed: 01/10/2023] Open
Abstract
Background Bronchopulmonary dysplasia continues to cause important respiratory morbidity throughout life, and new therapies are needed. The common denominator of all BPD cases is preterm birth, however most preclinical research in this area focusses on the effect of hyperoxia or mechanical ventilation. In this study we investigated if and how prematurity affects lung structure and function in neonatal rabbits. Methods Pups were delivered on either day 28 or day 31. For each gestational age a group of pups was harvested immediately after birth for lung morphometry and surfactant protein B and C quantification. All other pups were hand raised and harvested on day 4 for the term pups and day 7 for the preterm pups (same corrected age) for lung morphometry, lung function testing and qPCR. A subset of pups underwent microCT and dark field imaging on day 0, 2 and 4 for terms and on day 0, 3, 5 and 7 for preterms. Results Preterm pups assessed at birth depicted a more rudimentary lung structure (larger alveoli and thicker septations) and a lower expression of surfactant proteins in comparison to term pups. MicroCT and dark field imaging revealed delayed lung aeration in preterm pups, in comparison to term pups. Preterm birth led to smaller pups, with smaller lungs with a lower alveolar surface area on day 7/day 4. Furthermore, preterm birth affected lung function with increased tissue damping, tissue elastance and resistance and decreased dynamic compliance. Expression of vascular endothelial growth factor (VEGFA) was significantly decreased in preterm pups, however in the absence of structural vascular differences. Conclusions Preterm birth affects lung structure and function at birth, but also has persistent effects on the developing lung. This supports the use of a preterm animal model, such as the preterm rabbit, for preclinical research on BPD. Future research that focuses on the identification of pathways that are involved in in-utero lung development and disrupted by pre-term birth, could lead to novel therapeutic strategies for BPD.
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Affiliation(s)
- Thomas Salaets
- Department of Development and Regeneration, KULeuven, Herestraat 49, 3000, Leuven, Belgium.
| | - Margo Aertgeerts
- Department of Development and Regeneration, KULeuven, Herestraat 49, 3000, Leuven, Belgium
| | - André Gie
- Department of Development and Regeneration, KULeuven, Herestraat 49, 3000, Leuven, Belgium
| | - Janne Vignero
- Department of Imaging and Pathology, KU Leuven, Leuven, Belgium
| | - Derek de Winter
- Department of Development and Regeneration, KULeuven, Herestraat 49, 3000, Leuven, Belgium
| | - Yannick Regin
- Department of Development and Regeneration, KULeuven, Herestraat 49, 3000, Leuven, Belgium
| | - Julio Jimenez
- Facultad de Medicina, Universidad del Desarollo, Clínica Alemana, Santiago de Chile, Chile
| | | | - Karel Allegaert
- Department of Development and Regeneration, KULeuven, Herestraat 49, 3000, Leuven, Belgium.,Department of Clinical Pharmacy, Erasmus MC Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Jan Deprest
- Department of Development and Regeneration, KULeuven, Herestraat 49, 3000, Leuven, Belgium.,Institute for Women's Health, University College London Hospital, London, UK
| | - Jaan Toelen
- Department of Development and Regeneration, KULeuven, Herestraat 49, 3000, Leuven, Belgium
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15
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Veneroni C, Dahl MJ, Lavizzari A, Dawson E, Rebentisch A, Studstill S, Bowen S, Albertine KH, Dellaca RL. Non-invasive measurements of respiratory system mechanical properties by the forced oscillation technique in spontaneously breathing, mixed-breed, normal term lambs from birth to five months of age. Physiol Meas 2019; 40:105007. [PMID: 31341100 DOI: 10.1088/1361-6579/ab3493] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE To provide a non-invasive approach to monitoring lung function in spontaneously breathing lambs, from birth to five months of life, by the forced oscillation technique (FOT). This report describes the experimental set-up, data processing, and identification of normal predicted values of resistance (Rrs) and reactance (Xrs) of the respiratory system, along with normal bronchodilator response for bronchial reversibility testing. APPROACH Rrs and Xrs at 5, 11, and 19 Hz were measured monthly for five months in 20 normal term lambs that breathed spontaneously. In seven lambs, repeated measurements also were made within the first month of life (at 3, 7, 14, and 21 d of life). We determined the repeatability and reproducibility of the measurements and characterized the relationship between lung mechanics and age, sex, and body dimensions, using regression analysis, and measured changes in lung mechanics in response to inhaled bronchodilator. MAIN RESULTS The measurements provided repeatable and reproducible data. Rrs decreased, whereas Xrs increased, with growth from birth through the first two months of life, after which no statistically significant differences were detected. We identified normal value equations for Rrs and Xrs and for each of the measured anthropometric variables. Respiratory system mechanics were not affected by the bronchodilator. SIGNIFICANCE The FOT provides reliable non-invasive measurement of respiratory system mechanics in spontaneously breathing term lambs from birth to five months of age. The methods and normal reference values defined in this study will facilitate testing of the pathophysiological consequences of preterm birth and prolonged respiratory support on respiratory system mechanics.
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Affiliation(s)
- Chiara Veneroni
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano University, Milano, Italy. Co-first and co-last authors. Author to whom any correspondence should be addressed
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16
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Molgat-Seon Y, Dominelli PB, Peters CM, Guenette JA, Sheel AW, Gladstone IM, Lovering AT, Duke JW. Analysis of maximal expiratory flow-volume curves in adult survivors of preterm birth. Am J Physiol Regul Integr Comp Physiol 2019; 317:R588-R596. [PMID: 31433666 DOI: 10.1152/ajpregu.00114.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Adult survivors of very preterm (≤32 wk gestational age) birth without (PRE) and with bronchopulmonary dysplasia (BPD) have variable degrees of airflow obstruction at rest. Assessment of the shape of the maximal expiratory flow-volume (MEFV) curve in PRE and BPD may provide information concerning their unique pattern of airflow obstruction. The purposes of the present study were to 1) quantitatively assess the shape of the MEFV curve in PRE, BPD, and healthy adults born at full-term (CON), 2) identify where along the MEFV curve differences in shape existed between groups, and 3) determine the association between an index of MEFV curve shape and characteristics of preterm birth (i.e., gestational age, mass at birth, duration of oxygen therapy) in PRE and BPD. To do so, we calculated the average slope ratio (SR) throughout the effort-independent portion of the MEFV curve and at increments of 5% of forced vital capacity (FVC) between 20 and 80% of FVC in PRE (n = 19), BPD (n = 25), and CON (n = 20). We found that average SR was significantly higher in PRE (1.34 ± 0.35) and BPD (1.33 ± 0.45) compared with CON (1.03 ± 0.22; both P < 0.05) but similar between PRE and BPD (P = 0.99). Differences in SR between groups occurred early in expiration (i.e., 20-30% of FVC). There was no association between SR and characteristics of preterm birth in PRE and BPD groups (all P > 0.05). The mechanism(s) of increased SR during early expiration in PRE/BPD relative to CON is unknown but may be due to differences in the structural and mechanical properties of the airways.
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Affiliation(s)
- Yannick Molgat-Seon
- Department of Kinesiology and Applied Health, University of Winnipeg, Winnipeg, Manitoba, Canada.,Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada.,Centre for Heart and Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Paolo B Dominelli
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - Carli M Peters
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jordan A Guenette
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada.,Centre for Heart and Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada.,School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - A William Sheel
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Igor M Gladstone
- Oregon Health and Sciences University, Department of Paediatrics, Portland, Oregon
| | - Andrew T Lovering
- Department of Human Physiology, University of Oregon, Eugene, Oregon
| | - Joseph W Duke
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
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17
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Evans DJ, Schultz A, Verheggen M, Hall GL, Simpson SJ. Identifying pediatric lung disease: A comparison of forced oscillation technique outcomes. Pediatr Pulmonol 2019; 54:751-758. [PMID: 30887730 DOI: 10.1002/ppul.24286] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 01/10/2019] [Indexed: 11/07/2022]
Abstract
RATIONALE Increasing evidence suggests the forced oscillation technique (FOT) has the capacity to provide non-invasive monitoring and diagnosis of respiratory disease in young children. However, which FOT outcomes provide the most pertinent clinical information is currently unknown. The aim of this study was to determine which FOT outcomes were most sensitive for differentiating between health and specific childhood respiratory disease. METHODS Respiratory impedance was measured using a commercial device (i2M, Chess Medical, Belgium) in children aged between 3 and 7 years, who had been diagnosed with either cystic fibrosis (N = 84), asthma (N = 99) or were born very preterm (N = 114). Z-scores were calculated for respiratory system resistance (Rrs) and reactance (Xrs) at 6, 8, and 10 Hz, the resonance frequency (Fres), frequency dependence (Fdep4-24 ), and area under the reactance curve (AX). Pairwise comparisons of the area under the receiver operating characteristic (ROC) curve were used to determine the most relevant FOT variables. RESULTS AND CONCLUSIONS The FOT outcomes best able to discern between health and disease were Fres (P < 0.0001) in cystic fibrosis, Fres (P < 0.0001) in asthma and Xrs8 (P < 0.0001) in children born preterm. These findings suggest the utility of specific FOT outcomes is dependent on the respiratory disease being assessed. It is hoped that a disease-specific approach to interpreting FOT data can help further refine the FOT technique to aid in the diagnosis of children with pediatric respiratory disease.
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Affiliation(s)
- Denby J Evans
- Telethon Kids Institute, Nedlands, Western Australia, Australia
| | - Andre Schultz
- Telethon Kids Institute, Nedlands, Western Australia, Australia.,Division of Pediatrics, Faculty of Health and Medical Sciences, University of Western Australia, Nedlands, Perth, Western Australia, Australia.,Department of Respiratory Medicine, Perth Children's Hospital, Nedlands, Perth, Western Australia, Australia
| | - Maureen Verheggen
- Telethon Kids Institute, Nedlands, Western Australia, Australia.,Division of Pediatrics, Faculty of Health and Medical Sciences, University of Western Australia, Nedlands, Perth, Western Australia, Australia.,Department of Respiratory Medicine, Perth Children's Hospital, Nedlands, Perth, Western Australia, Australia
| | - Graham L Hall
- Telethon Kids Institute, Nedlands, Western Australia, Australia.,School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Australia
| | - Shannon J Simpson
- Telethon Kids Institute, Nedlands, Western Australia, Australia.,School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Australia
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18
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Lombardi E, Fainardi V, Calogero C, Puglia M, Voller F, Cuttini M, Rusconi F. Lung function in a cohort of 5-year-old children born very preterm. Pediatr Pulmonol 2018; 53:1633-1639. [PMID: 30345653 DOI: 10.1002/ppul.24179] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 09/21/2018] [Indexed: 01/17/2023]
Abstract
OBJECTIVE We assessed lung function and respiratory health in an area-based prospective cohort of preschool children born very preterm. DESIGN Lung function was measured by interrupter respiratory resistance (Rint) and forced oscillation technique (FOT) (respiratory resistance (Rrs8), reactance (Xrs8), and area under the reactance curve (AX)) at a median age of 5.2 years in a cohort of 194 children born at 22-31 weeks of gestational age (GA) in Tuscany, Italy. Respiratory symptoms and hospitalizations were also assessed. RESULTS Mean (SD) lung function Z-scores were impaired in preterm children for Rint (0.72 (1.13)), Xrs8 (-0.28 (1.34)), and AX (0.29 (1.41)). However, only a relatively small proportion of children (14.5-17.4%) had values beyond the 95th centile or below the 5th. Children with bronchopulmonary dysplasia (BPD) (n = 24) had slightly but not significantly impaired lung function indices in comparison with those without BPD (n = 170). In a multivariable analysis, lower GA was associated with worse lung function indices. Fifty-five percent of children had a history of wheezing ever and 21% had been hospitalized in their lifetime because of lower respiratory infections; 31% had wheezing in the last 12 months and this was associated with increased Rrs8 (P = 0.04) and AX (P = 0.08), and with decreased Xrs8 (P = 0.04) Z-scores. CONCLUSIONS Irrespectively of BPD preschool children born very preterm had impaired lung function indices, as measured by Rint and FOT, and a slightly higher burden of respiratory problems than the general population. GA seems to be crucial for lung development.
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Affiliation(s)
- Enrico Lombardi
- Pediatric Pulmonary Unit, Meyer Children's University Hospital, Florence, Italy
| | | | - Claudia Calogero
- Pediatric Pulmonary Unit, Meyer Children's University Hospital, Florence, Italy
| | - Monia Puglia
- Unit of Epidemiology, Health Agency of Tuscany, Florence, Italy
| | - Fabio Voller
- Unit of Epidemiology, Health Agency of Tuscany, Florence, Italy
| | - Marina Cuttini
- Clinical Care and Management Innovation Research Area, Bambino Gesù Pediatric Hospital, IRCCS, Rome, Italy
| | - Franca Rusconi
- Unit of Epidemiology, Meyer Children's University Hospital, Florence, Italy
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19
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Urs R, Kotecha S, Hall GL, Simpson SJ. Persistent and progressive long-term lung disease in survivors of preterm birth. Paediatr Respir Rev 2018; 28:87-94. [PMID: 29752125 DOI: 10.1016/j.prrv.2018.04.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 04/09/2018] [Indexed: 02/05/2023]
Abstract
Preterm birth accounts for approximately 11% of births globally, with rates increasing across many countries. Concurrent advances in neonatal care have led to increased survival of infants of lower gestational age (GA). However, infants born <32 weeks of GA experience adverse respiratory outcomes, manifesting with increased respiratory symptoms, hospitalisation and health care utilisation into early childhood. The development of bronchopulmonary dysplasia (BPD) - the chronic lung disease of prematurity - further increases the risk of poor respiratory outcomes throughout childhood, into adolescence and adulthood. Indeed, survivors of preterm birth have shown increased respiratory symptoms, altered lung structure, persistent and even declining lung function throughout childhood. The mechanisms behind this persistent and sometimes progressive lung disease are unclear, and the implications place those born preterm at increased risk of respiratory morbidity into adulthood. This review aims to summarise what is known about the long-term pulmonary outcomes of contemporary preterm birth, examine the possible mechanisms of long-term respiratory morbidity in those born preterm and discuss addressing the unknowns and potentials for targeted treatments.
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Affiliation(s)
- Rhea Urs
- Telethon Kids Institute, Perth, Australia; School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Australia
| | - Sailesh Kotecha
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, UK
| | - Graham L Hall
- Telethon Kids Institute, Perth, Australia; School of Physiotherapy and Exercise Science, Faculty of Health Sciences, Curtin University, Perth, Australia
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20
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Fainardi V, Lombardi E. Lung function tests to monitor respiratory disease in preschool children. ACTA BIO-MEDICA : ATENEI PARMENSIS 2018; 89:148-156. [PMID: 29957746 PMCID: PMC6179029 DOI: 10.23750/abm.v89i2.7155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Accepted: 04/06/2018] [Indexed: 01/22/2023]
Abstract
Pulmonary function tests are routinely used in the diagnosis and follow-up of respiratory diseases. In preschool children assessment and evaluation of lung function has always been challenging but improved techniques that require only minimal collaboration allowed obtaining reliable and useful results even in this group of patients. In this review we will describe the different techniques used in clinical practice to measure lung function in preschool children.(www.actabiomedica.it)
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Affiliation(s)
| | - Enrico Lombardi
- Paediatric Pulmonary Unit, "Anna Meyer" Paediatric University Hospital, Florence, Italy.
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21
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Abstract
Chronic respiratory morbidity is a common complication of premature birth, generally defined by the presence of bronchopulmonary dysplasia, both clinically and in trials of respiratory therapies. However, recent data have highlighted that bronchopulmonary dysplasia does not correlate with chronic respiratory morbidity in older children born preterm. Longitudinally evaluating pulmonary morbidity from early life through to childhood provides a more rational method of defining the continuum of chronic respiratory morbidity of prematurity, and offers new insights into the efficacy of neonatal respiratory interventions. The changing nature of preterm lung disease suggests that a multimodal approach using dynamic lung function assessment will be needed to assess the efficacy of a neonatal respiratory therapy and predict the long-term respiratory consequences of premature birth. Our aim is to review the literature regarding the long-term respiratory outcomes of neonatal respiratory strategies, the difficulties of assessing dynamic lung function in infants, and potential new solutions. Better measures are needed to predict chronic respiratory morbidity in survivors born prematurely http://ow.ly/1L3n30ihq9C
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22
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23
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Shackleton C, Czovek D, Grimwood K, Ware RS, Radics B, Hantos Z, Sly PD. Defining 'healthy' in preschool-aged children for forced oscillation technique reference equations. Respirology 2017; 23:406-413. [PMID: 28981187 DOI: 10.1111/resp.13186] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 07/13/2017] [Accepted: 08/28/2017] [Indexed: 01/23/2023]
Abstract
BACKGROUND AND OBJECTIVE Selecting 'healthy' preschool-aged children for reference ranges may not be straightforward. Relaxing inclusion criteria for normative data does not affect spirometry z-scores. We therefore investigated the effect of similarly relaxing inclusion criteria in preschoolers on reference ranges for respiratory impedance (Zrs) using a modified forced oscillation technique (FOT). METHODS The International Study of Asthma and Allergies in Childhood questionnaire classified 585 children into a healthy and five mutually exclusive groups. Zrs was measured between 4 and 26 Hz and resistance (R) and compliance (C) obtained by model fitting. Prediction models were determined using mixed effect models and z-scores compared between healthy children and the five groups. RESULTS Zrs data were obtained for 494 participants (4.30 ± 0.7 years) on 587 occasions. Comparison of the Zrs z-scores between the healthy children and the health groups found significant differences in children with asthma, current wheeze and respiratory symptoms, but not in children born preterm or with early-life wheeze. Adding these two groups to the healthy dataset had no significant effect on the distribution of z-scores and increased the size of the dataset by 22.3%. CONCLUSION Our data suggest that preschool-aged children born preterm or with early-life wheeze can be included in FOT reference equations, while those with asthma, current wheeze and respiratory symptoms within 4 weeks of testing should be excluded. This more inclusive approach results in more robust FOT reference ranges.
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Affiliation(s)
- Claire Shackleton
- Children's Lung Environment and Asthma Research, Child Health Research Centre, The University of Queensland, Brisbane, QLD, Australia
| | - Dorottya Czovek
- Children's Lung Environment and Asthma Research, Child Health Research Centre, The University of Queensland, Brisbane, QLD, Australia
| | - Keith Grimwood
- School of Medicine and Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia.,Departments of Infectious Diseases and Paediatrics, Gold Coast Health, Gold Coast, QLD, Australia
| | - Robert S Ware
- School of Medicine and Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Bence Radics
- Department of Pulmonology, University of Szeged, Deszk, Hungary
| | - Zoltan Hantos
- Children's Lung Environment and Asthma Research, Child Health Research Centre, The University of Queensland, Brisbane, QLD, Australia.,Department of Pulmonology, University of Szeged, Deszk, Hungary
| | - Peter D Sly
- Children's Lung Environment and Asthma Research, Child Health Research Centre, The University of Queensland, Brisbane, QLD, Australia
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Udomittipong K, Srisukhon W, Nimmannit A, Komoltri C. Respiratory Impedance Reference Values for Forced Oscillation Technique Predicted by Arm Span and Height in Thai Preschool Children. PEDIATRIC ALLERGY, IMMUNOLOGY, AND PULMONOLOGY 2017. [DOI: 10.1089/ped.2017.0747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Kanokporn Udomittipong
- Division of Pulmonology, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Wichuta Srisukhon
- Division of Pulmonology, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Akarin Nimmannit
- Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Chulaluk Komoltri
- Division of Clinical Epidemiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
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Verheggen M, Wilson AC, Pillow JJ, Stick SM, Hall GL. Respiratory function and symptoms in young preterm children in the contemporary era. Pediatr Pulmonol 2016; 51:1347-1355. [PMID: 27228468 DOI: 10.1002/ppul.23487] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 04/14/2016] [Accepted: 04/24/2016] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To determine the relationships between respiratory symptoms, lung function, and neonatal events in young preterm children. METHODS Preterm children (<32 w gestation), classified as bronchopulmonary dysplasia (BPD) or non-BPD, and healthy term controls were studied. Lung function was measured by forced oscillation technique (respiratory resistance [Rrs] and reactance [Xrs]) and spirometry. Respiratory symptom questionnaires were administered. RESULTS One hundred and fifty children (74 BPD, 44 non-BPD, 32 controls) 4-8 years were studied. Lung function (median Z-score [10,90th centile]) was significantly impaired in preterm children compared to controls for FVC (0.00 [-1.18, 1.76], 0.69 [-0.17,1.86]), FEV1 (-0.44 [-1.94, 1.11], 0.49 [-0.83, 2.51]), Xrs (-1.26 [-3.31, 0.11], -0.11 [-0.97, 0.73]), and Rrs (0.55 [-0.48, 1.82], 0.28 [-0.99, 0.96]). Only Xrs differed between the BPD and non-BPD (-1.51 [-3.59, -0.41], -0.89 [-2.64, 0.52]). The prevalence of recent respiratory symptoms (range: 32-36%) did not differ between BPD and non-BPD children. Supplemental O2 in hospital was positively associated with worsening Xrs and FEV1 . CONCLUSION Preterm children have worse lung function than healthy controls. Only respiratory reactance differentiated between preterm children with and without BPD and was influenced by days of O2 in hospital. Pediatr Pulmonol. 2016;51:1347-1355. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Maureen Verheggen
- Department of Respiratory Medicine, Princess Margaret Hospital for Children, GPO Box D184, Perth 6840, Australia.,University of Western Australia, School of Paediatrics and Child Health, Perth, Australia.,Telethon Kids, Perth, Australia
| | - Andrew C Wilson
- Department of Respiratory Medicine, Princess Margaret Hospital for Children, GPO Box D184, Perth 6840, Australia.,University of Western Australia, School of Paediatrics and Child Health, Perth, Australia.,Telethon Kids, Perth, Australia.,School of Physiotherapy and Exercise Science, Curtin University, Perth, Australia
| | - J Jane Pillow
- University of Western Australia, School of Anatomy, Physiology and Human Biology, Perth, Australia.,University of Western Australia, Centre for Neonatal Research and Education, Perth, Australia.,King Edward Memorial Hospital, Perth, Australia
| | - Stephen M Stick
- Department of Respiratory Medicine, Princess Margaret Hospital for Children, GPO Box D184, Perth 6840, Australia.,University of Western Australia, School of Paediatrics and Child Health, Perth, Australia.,Telethon Kids, Perth, Australia.,Centre for Child Health University of Western Australia, Perth, Australia
| | - Graham L Hall
- Department of Respiratory Medicine, Princess Margaret Hospital for Children, GPO Box D184, Perth 6840, Australia.,Telethon Kids, Perth, Australia.,School of Physiotherapy and Exercise Science, Curtin University, Perth, Australia.,Centre for Child Health University of Western Australia, Perth, Australia
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Czövek D, Shackleton C, Hantos Z, Taylor K, Kumar A, Chacko A, Ware RS, Makan G, Radics B, Gingl Z, Sly PD. Tidal changes in respiratory resistance are sensitive indicators of airway obstruction in children. Thorax 2016; 71:907-15. [PMID: 27178219 DOI: 10.1136/thoraxjnl-2015-208182] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 04/17/2016] [Indexed: 11/04/2022]
Abstract
RATIONALE Individual assessment of airway obstruction in preschool-age children requires sensitive and specific lung function methods with low demand of cooperation. Although the forced oscillation technique (FOT) is feasible in young children, conventional measurements of respiratory impedance (Zrs) have limited diagnostic power in individuals. OBJECTIVE To find descriptors of within-breath Zrs that are sensitive indicators of airway obstruction during tidal breathing in children. METHODS Zrs was measured with (i) a standard multifrequency FOT (4-26 Hz) to assess the mean values of resistance and reactance for whole breaths and (ii) a 10 Hz signal to track the within-breath changes. Various Zrs measures obtained in healthy children (n=75) and those with acute wheeze (n=31) were investigated with receiver operator characteristic (ROC) analysis. The cut-off values obtained for airway obstruction were then tested in children with recurrent wheeze (n=20) before and after administration of salbutamol. RESULTS The largest area under the ROC curve (0.95) was observed for the tidal changes of resistance between the zero-flow values (ΔR). The ΔR cut-off value of 1.42 hPa s/L detected airway obstruction with sensitivity of 92% and specificity of 89% in children with acute wheeze and distinguished children with recurrent wheeze (16/20 above the cut-off value) from healthy children (22/23 below the cut-off value). Furthermore, ΔR significantly decreased after salbutamol in wheezy children but remained unchanged in healthy children. CONCLUSIONS New lung function measure ΔR is able to detect airway obstruction with high sensitivity and specificity and is suitable for use in lung function testing in young children.
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Affiliation(s)
- Dorottya Czövek
- Children's Lung, Environment and Asthma Research Team, University of Queensland, Brisbane, Queensland, Australia Child Health Research Centre, University of Queensland, Brisbane, Queensland, Australia
| | - Claire Shackleton
- Children's Lung, Environment and Asthma Research Team, University of Queensland, Brisbane, Queensland, Australia Child Health Research Centre, University of Queensland, Brisbane, Queensland, Australia
| | - Zoltán Hantos
- Children's Lung, Environment and Asthma Research Team, University of Queensland, Brisbane, Queensland, Australia Child Health Research Centre, University of Queensland, Brisbane, Queensland, Australia Department of Medical Physics and Informatics, University of Szeged, Szeged, Hungary Department of Pulmonology, University of Szeged, Szeged, Hungary
| | - Kate Taylor
- Children's Lung, Environment and Asthma Research Team, University of Queensland, Brisbane, Queensland, Australia
| | - Anushma Kumar
- Children's Lung, Environment and Asthma Research Team, University of Queensland, Brisbane, Queensland, Australia
| | - Archana Chacko
- Children's Lung, Environment and Asthma Research Team, University of Queensland, Brisbane, Queensland, Australia
| | - Robert S Ware
- Child Health Research Centre, University of Queensland, Brisbane, Queensland, Australia
| | - Gergely Makan
- Department of Technical Informatics, University of Szeged, Szeged, Hungary
| | - Bence Radics
- Department of Pulmonology, University of Szeged, Szeged, Hungary
| | - Zoltán Gingl
- Department of Technical Informatics, University of Szeged, Szeged, Hungary
| | - Peter D Sly
- Children's Lung, Environment and Asthma Research Team, University of Queensland, Brisbane, Queensland, Australia Child Health Research Centre, University of Queensland, Brisbane, Queensland, Australia
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The Forced Oscillation Technique in Paediatric Respiratory Practice. Paediatr Respir Rev 2016; 18:46-51. [PMID: 26777151 DOI: 10.1016/j.prrv.2015.11.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 11/03/2015] [Indexed: 01/24/2023]
Abstract
The Forced Oscillation Technique (FOT) is a lung function modality based on the application of an external oscillatory signal in order to determine the mechanical response of the respiratory system. The method is in principal noninvasive and requires minimal patient cooperation, which makes it suitable for use in young paediatric patients. The FOT has been successfully applied in various paediatric respiratory disorders, such as asthma, cystic fibrosis, and chronic lung disease of prematurity, in order to assess airway obstruction, bronchodilator response, and airway responsiveness after bronchoprovocation challenge. This technique may be more sensitive than spirometry in identifying disturbances of peripheral airways and assessing the level of asthma control or the effectiveness of therapy at the long term. Further research is required to determine the exact role of the FOT in paediatric lung function testing and to incorporate the method in specific diagnostic and management algorithms.
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Ramsey KA, Ranganathan SC, Gangell CL, Turkovic L, Park J, Skoric B, Stick SM, Sly PD, Hall GL. Impact of lung disease on respiratory impedance in young children with cystic fibrosis. Eur Respir J 2015; 46:1672-9. [PMID: 26405283 DOI: 10.1183/13993003.00156-2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 07/14/2015] [Indexed: 11/05/2022]
Abstract
This study aimed to evaluate the ability of the forced oscillation technique (FOT) to detect underlying lung disease in preschool children with cystic fibrosis (CF) diagnosed following newborn screening.184 children (aged 3-6 years) with CF underwent lung function testing on 422 occasions using the FOT to assess respiratory resistance and reactance at the time of their annual bronchoalveolar lavage collection and chest computed tomography scan. We examined associations between FOT outcomes and the presence and progression of respiratory inflammation, infection and structural lung disease.Children with CF who had pronounced respiratory disease, including free neutrophil elastase activity, infection with pro-inflammatory pathogens and structural lung abnormalities had similar FOT outcomes to those children without detectable lung disease. In addition, the progression of lung disease over 1 year was not associated with worsening FOT outcomes.We conclude that the forced oscillation technique is relatively insensitive to detect underlying lung disease in preschool children with CF. However, FOT may still be of value in improving our understanding of the physiological changes associated with early CF lung disease.
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Affiliation(s)
- Kathryn A Ramsey
- Telethon Kids Institute, University of Western Australia, Subiaco, Australia Cystic Fibrosis Research and Treatment Centre, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Sarath C Ranganathan
- Murdoch Childrens Research Institute, Parkville, Australia Department of Respiratory Medicine, Royal Children's Hospital, Parkville, Australia Department of Paediatrics, University of Melbourne, Parkville, Australia
| | - Catherine L Gangell
- Telethon Kids Institute, University of Western Australia, Subiaco, Australia Queensland Children's Medical Research Institute, The University of Queensland, Herston, Australia
| | - Lidija Turkovic
- Telethon Kids Institute, University of Western Australia, Subiaco, Australia
| | - Judy Park
- Telethon Kids Institute, University of Western Australia, Subiaco, Australia
| | - Billy Skoric
- Murdoch Childrens Research Institute, Parkville, Australia Department of Respiratory Medicine, Royal Children's Hospital, Parkville, Australia
| | - Stephen M Stick
- Telethon Kids Institute, University of Western Australia, Subiaco, Australia Department of Respiratory Medicine, Princess Margaret Hospital for Children, Subiaco, Australia
| | - Peter D Sly
- Queensland Children's Medical Research Institute, The University of Queensland, Herston, Australia
| | - Graham L Hall
- Telethon Kids Institute, University of Western Australia, Subiaco, Australia
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Simpson SJ, Hall GL, Wilson AC. Lung function following very preterm birth in the era of ‘new’ bronchopulmonary dysplasia. Respirology 2015; 20:535-40. [DOI: 10.1111/resp.12503] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/07/2014] [Accepted: 12/29/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Shannon J. Simpson
- Telethon Kids Institute; The University of Western Australia; Perth Western Australia Australia
| | - Graham L. Hall
- Telethon Kids Institute; The University of Western Australia; Perth Western Australia Australia
| | - Andrew C. Wilson
- Department of Respiratory Medicine; Princess Margaret Hospital for Children; Perth Western Australia Australia
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Vogt B, Falkenberg C, Weiler N, Frerichs I. Pulmonary function testing in children and infants. Physiol Meas 2014; 35:R59-90. [PMID: 24557323 DOI: 10.1088/0967-3334/35/3/r59] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Pulmonary function testing is performed in children and infants with the aim of documenting lung development with age and making diagnoses of lung diseases. In children and infants with an established lung disease, pulmonary function is tested to assess the disease progression and the efficacy of therapy. It is difficult to carry out the measurements in this age group without disturbances, so obtaining results of good quality and reproducibility is challenging. Young children are often uncooperative during the examinations. This is partly related to their young age but also due to the long testing duration and the unpopular equipment. We address a variety of examination techniques for lung function assessment in children and infants in this review. We describe the measuring principles, examination procedures, clinical findings and their interpretation, as well as advantages and limitations of these methods. The comparability between devices and centres as well as the availability of reference values are still considered a challenge in many of these techniques. In recent years, new technologies have emerged allowing the assessment of lung function not only on the global level but also on the regional level. This opens new possibilities for detecting regional lung function heterogeneity that might lead to a better understanding of respiratory pathophysiology in children.
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Affiliation(s)
- B Vogt
- Department of Anaesthesiology and Intensive Care Medicine, University Medical Centre Schleswig-Holstein, Campus Kiel, Kiel, Germany
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Bates JHT, Irvin CG, Farré R, Hantos Z. Oscillation mechanics of the respiratory system. Compr Physiol 2013; 1:1233-72. [PMID: 23733641 DOI: 10.1002/cphy.c100058] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The mechanical impedance of the respiratory system defines the pressure profile required to drive a unit of oscillatory flow into the lungs. Impedance is a function of oscillation frequency, and is measured using the forced oscillation technique. Digital signal processing methods, most notably the Fourier transform, are used to calculate impedance from measured oscillatory pressures and flows. Impedance is a complex function of frequency, having both real and imaginary parts that vary with frequency in ways that can be used empirically to distinguish normal lung function from a variety of different pathologies. The most useful diagnostic information is gained when anatomically based mathematical models are fit to measurements of impedance. The simplest such model consists of a single flow-resistive conduit connecting to a single elastic compartment. Models of greater complexity may have two or more compartments, and provide more accurate fits to impedance measurements over a variety of different frequency ranges. The model that currently enjoys the widest application in studies of animal models of lung disease consists of a single airway serving an alveolar compartment comprising tissue with a constant-phase impedance. This model has been shown to fit very accurately to a wide range of impedance data, yet contains only four free parameters, and as such is highly parsimonious. The measurement of impedance in human patients is also now rapidly gaining acceptance, and promises to provide a more comprehensible assessment of lung function than parameters derived from conventional spirometry.
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Affiliation(s)
- Jason H T Bates
- Vermont Lung Center, University of Vermont College of Medicine, Burlington, Vermont, USA.
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An official American Thoracic Society workshop report: optimal lung function tests for monitoring cystic fibrosis, bronchopulmonary dysplasia, and recurrent wheezing in children less than 6 years of age. Ann Am Thorac Soc 2013; 10:S1-S11. [PMID: 23607855 DOI: 10.1513/annalsats.201301-017st] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Although pulmonary function testing plays a key role in the diagnosis and management of chronic pulmonary conditions in children under 6 years of age, objective physiologic assessment is limited in the clinical care of infants and children less than 6 years old, due to the challenges of measuring lung function in this age range. Ongoing research in lung function testing in infants, toddlers, and preschoolers has resulted in techniques that show promise as safe, feasible, and potentially clinically useful tests. Official American Thoracic Society workshops were convened in 2009 and 2010 to review six lung function tests based on a comprehensive review of the literature (infant raised-volume rapid thoracic compression and plethysmography, preschool spirometry, specific airway resistance, forced oscillation, the interrupter technique, and multiple-breath washout). In these proceedings, the current state of the art for each of these tests is reviewed as it applies to the clinical management of infants and children under 6 years of age with cystic fibrosis, bronchopulmonary dysplasia, and recurrent wheeze, using a standardized format that allows easy comparison between the measures. Although insufficient evidence exists to recommend incorporation of these tests into the routine diagnostic evaluation and clinical monitoring of infants and young children with cystic fibrosis, bronchopulmonary dysplasia, or recurrent wheeze, they may be valuable tools with which to address specific concerns, such as ongoing symptoms or monitoring response to treatment, and as outcome measures in clinical research studies.
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Calogero C, Simpson SJ, Lombardi E, Parri N, Cuomo B, Palumbo M, de Martino M, Shackleton C, Verheggen M, Gavidia T, Franklin PJ, Kusel MMH, Park J, Sly PD, Hall GL. Respiratory impedance and bronchodilator responsiveness in healthy children aged 2-13 years. Pediatr Pulmonol 2013; 48:707-15. [PMID: 23169525 DOI: 10.1002/ppul.22699] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 08/03/2012] [Indexed: 01/04/2023]
Abstract
BACKGROUND The forced oscillation technique (FOT) can be used in children as young as 2 years of age and in those unable to perform routine spirometry. There is limited information on changes in FOT outcomes in healthy children beyond the preschool years and the level of bronchodilator responsiveness (BDR) in healthy children. We aimed to create reference ranges for respiratory impedance outcomes collated from multiple centers. Outcomes included respiratory system resistance (R(rs)) and reactance (X(rs)), resonant frequency (Fres), frequency dependence of R(rs) (Fdep), and the area under the reactance curve (AX). We also aimed to define the physiological effects of bronchodilators in a large population of healthy children using the FOT. METHODS Respiratory impedance was measured in 760 healthy children, aged 2-13 years, from Australia and Italy. Stepwise linear regression identified anthropometric predictors of transformed R(rs) and X(rs) at 6, 8, and 10 Hz, Fres, Fdep, and AX. Bronchodilator response (BDR) was assessed in 508 children after 200 µg of inhaled salbutamol. RESULTS Regression analysis showed that R(rs), X(rs), and AX outcomes were dependent on height and sex. The BDR cut-offs by absolute change in R(rs8), X(rs8), and AX were -2.74 hPa s L(-1), 1.93 hPa s L(-1), and -33 hPa s L(-1), respectively. These corresponded to relative and Z-score changes of -32%; -1.85 for R(rs8), 65%; 1.95 for X(rs8), and -82%; -2.04 for AX. CONCLUSIONS We have established generalizable reference ranges for respiratory impedance and defined cut-offs for a positive bronchodilator response using the FOT in healthy children.
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Affiliation(s)
- Claudia Calogero
- Unit of Respiratory Medicine, Department of Paediatrics, University of Florence, Anna Meyer University Hospital for Children, Florence, Italy
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Shackleton C, Barraza-Villarreal A, Chen L, Gangell CL, Romieu I, Sly PD. Reference ranges for Mexican preschool-aged children using the forced oscillation technique. Arch Bronconeumol 2013; 49:326-9. [PMID: 23587799 DOI: 10.1016/j.arbres.2013.01.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 01/17/2013] [Accepted: 01/17/2013] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Recently, multi-ethnic reference ranges for spirometry have been created for use worldwide. In comparison, forced oscillation technique (FOT) reference values are limited to specific equipment and study populations, with current FOT reference ranges created in a Caucasian population. We aimed to develop FOT reference ranges for preschool-aged Mexican children and to compare these with current FOT reference ranges. PATIENTS AND METHODS Respiratory resistance (Rrs) and reactance (Xrs) was measured in healthy Mexican children three to five years of age using commercial FOT equipment. The relationship between height and Rrs and Xrs was determined using regression analyses, taking into account age, weight, sex, and exposure to tobacco smoke. Reference equations were calculated for the Mexican children and Z-scores determined for Rrs and Xrs at 6 and 8Hz. A paired t-test assessed the difference in Z-scores between the Australian reference values and those created for the Mexican cohort. RESULTS FOT was successfully measured in 584 children. Height was a significant predictor of Rrs and Xrs at 6 and 8Hz (P<.05). Z-scores calculated using the Australian reference equations overestimated lung function in Mexican children for both Rrs and Xrs at 6 and 8Hz (P<.001). CONCLUSION The development of FOT reference ranges specific to Mexican preschool-aged children will allow for the correct interpretation of FOT measurements. This study also showed that current FOT reference ranges overestimate lung function in Mexican children. Highlighting, the importance of using ethnic appropriate reference ranges for interpreting lung function.
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Affiliation(s)
- Claire Shackleton
- Queensland Children's Medical Research Institute, The University of Queensland, Brisbane, Australia.
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Peták F, Czövek D, Novák Z. Spirometry and forced oscillations in the detection of airway hyperreactivity in asthmatic children. Pediatr Pulmonol 2012; 47:956-65. [PMID: 22451241 DOI: 10.1002/ppul.22551] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 12/29/2011] [Indexed: 12/18/2022]
Abstract
BACKGROUND Provocation tests are routinely used to detect airway hyperreactivity (AH) in the diagnosis of asthma. We compared the sensitivities of the forced oscillation technique (FOT) and spirometry in the detection of AH in asthmatic children. METHODS FOT and spirometry were performed in 20 asthmatic children (aged 5-18 years) following aerosolized histamine and methacholine at an interval of 2 weeks. The respiratory system input impedance was measured by FOT; the resistance at 6 Hz (R(6) ), the average resistance between 4 and 24 Hz, the area under the reactance curve (AX) and the resonant frequency were extracted from these recordings. Spirometry was used to obtain forced expiratory volumes and flow parameters. RESULTS Following provocation with the two agonists, the FOT detected the airway response as early as spirometry. When the greater variability of the impedance parameters was taken into account, the two methods were observed to have similar sensitivities. Among the lung function parameters studied, AX and R(6) were the most sensitive for the demonstration of AH. CONCLUSIONS Our findings demonstrate that FOT is as suitable as spirometry for the measurement of bronchoconstriction and thus it may be considered for the detection of AH in asthmatic children. Since its application requires minimal cooperation, this approach imposes less stress and may be particularly favorable in the diagnosis of asthma at a young age.
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Affiliation(s)
- Ferenc Peták
- Department of Medical Physics and Informatics, University of Szeged, Hungary.
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Mochizuki H, Hirai K, Tabata H. Forced oscillation technique and childhood asthma. Allergol Int 2012; 61:373-83. [PMID: 22722816 DOI: 10.2332/allergolint.12-rai-0440] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Indexed: 11/20/2022] Open
Abstract
Most infants and preschool children are not able to voluntarily perform the physiological maneuvers required to complete the pulmonary function tests that are used in adults and older children. Recently, commercial devices using forced oscillation technique (FOT) suitable for young children have become available. In devices with FOT, an oscillation pressure wave is generated by a loud speaker, is applied to the respiratory system, usually at the mouth, and the resulting pressure-flow relationship is analyzed in terms of impedance (Zrs). Zrs encompasses both resistance (Rrs) and reactance (Xrs). Rrs is calculated from pressure and flow signals, and is a measure of central and peripheral airway caliber. Xrs is derived from the pressure in the phase with volume and is related to compliance (Crs) and inertance (Irs). These parameters individually indicate the condition of the small and large airways in each patient and indirectly suggest the presence of airway inflammation. It is agreed that the clinical diagnostic capacity of FOT is comparable to that of spirometry. One of the advantages of FOT is that minimal cooperation of the patient is needed and no respiratory maneuvers are required. The use of FOT should be considered in patients in whom spirometry or other pulmonary function tests cannot be performed or in cases where the results of other tests appear to be unreliable. In addition, this approach is effective in assessing bronchial hyperresponsiveness. Considering these qualities, FOT is a useful method to study pulmonary function in preschool children with asthma.
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Affiliation(s)
- Hiroyuki Mochizuki
- Department of Pediatrics, Tokai University School of Medicine, Isehara, Kanagawa, Japan. mochihi@tokai−u.jp
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Seehase S, Schlepütz M, Switalla S, Mätz-Rensing K, Kaup FJ, Zöller M, Schlumbohm C, Fuchs E, Lauenstein HD, Winkler C, Kuehl AR, Uhlig S, Braun A, Sewald K, Martin C. Bronchoconstriction in nonhuman primates: a species comparison. J Appl Physiol (1985) 2011; 111:791-8. [PMID: 21700889 DOI: 10.1152/japplphysiol.00162.2011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Bronchoconstriction is a characteristic symptom of various chronic obstructive respiratory diseases such as chronic obstructive pulmonary disease and asthma. Precision-cut lung slices (PCLS) are a suitable ex vivo model to study physiological mechanisms of bronchoconstriction in different species. In the present study, we established an ex vivo model of bronchoconstriction in nonhuman primates (NHPs). PCLS prepared from common marmosets, cynomolgus macaques, rhesus macaques, and anubis baboons were stimulated with increasing concentrations of representative bronchoconstrictors: methacholine, histamine, serotonin, leukotriene D₄ (LTD₄), U46619, and endothelin-1. Alterations in the airway caliber were measured and compared with previously published data from rodents, guinea pigs, and humans. Methacholine induced maximal airway constriction, varying between 74 and 88% in all NHP species, whereas serotonin was ineffective. Histamine induced maximal bronchoconstriction of 77 to 90% in rhesus macaques, cynomolgus macaques, and baboons and a lesser constriction of 53% in marmosets. LTD₄ was ineffective in marmosets and rhesus macaques but induced a maximum constriction of 44 to 49% in cynomolgus macaques and baboons. U46619 and endothelin-1 caused airway constriction in all NHP species, with maximum constrictions of 65 to 91% and 70 to 81%, respectively. In conclusion, PCLS from NHPs represent a valuable ex vivo model for studying bronchoconstriction. All NHPs respond to mediators relevant to human airway disorders such as methacholine, histamine, U46619, and endothelin-1 and are insensitive to the rodent mast cell product serotonin. Only PCLS from cynomolgus macaques and baboons, however, responded also to leukotrienes, suggesting that among all compared species, these two NHPs resemble the human airway mechanisms best.
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Affiliation(s)
- S Seehase
- Department of Airway Immunology, Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover, Germany
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Lum S, Bush A, Stocks J. Clinical Pulmonary Function Testing for Children with Bronchopulmonary Dysplasia. PEDIATRIC ALLERGY IMMUNOLOGY AND PULMONOLOGY 2011; 24:77-88. [DOI: 10.1089/ped.2010.0059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Sooky Lum
- Portex Respiratory Unit, UCL, Institute of Child Health, London, United Kingdom
| | - Andrew Bush
- Department of Paediatrics, Royal Brompton Hospital, London, United Kingdom
| | - Janet Stocks
- Portex Respiratory Unit, UCL, Institute of Child Health, London, United Kingdom
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Calogero C, Parri N, Baccini A, Cuomo B, Palumbo M, Novembre E, Morello P, Azzari C, de Martino M, Sly PD, Lombardi E. Respiratory impedance and bronchodilator response in healthy Italian preschool children. Pediatr Pulmonol 2010; 45:1086-94. [PMID: 20672294 DOI: 10.1002/ppul.21292] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVE To define normal values for respiratory resistance (R(rs)) and reactance (X(rs)) and bronchodilator response (BDR) in a population of healthy Italian preschool children using a commercially available forced oscillation device. METHODS R(rs) and X(rs) were measured in kindergartens in Viterbo, Italy. Regression analysis was performed taking into account height, weight, age, gender, and reference equations calculated. The coefficient of repeatability (CR) between two tests performed 15 min apart was calculated in a subset of children. BDR was assessed by repeating the measurements 15 min after the administration of 200 µg of inhaled salbutamol and calculated as an absolute change in R(rs) and X(rs) at 8 Hz, as a percent change in baseline, and as a change in Z-score calculated from the reference equations. RESULTS Lung function was attempted in 175 healthy children and successful in 163 (81 male, median age 4.8, range 2.9-6.1 years). R(rs) and X(rs) at 6, 8, and 10 Hz were related to height but not other variables. The CR was 1.53 hPa s L(-1) for R(rs8) and 0.91 hPa s L(-1) for X(rs8). The 5th percentile for absolute R(rs8) BDR was -3.16 hPa s L(-1), whereas the 95th percentile for absolute X(rs8) BDR was 2.25 hPa s L(-1). These cut-off values corresponded to a change in the Z-score of -1.88 and 2.48, respectively. CONCLUSIONS We have established reference equations for R(rs) and X(rs) in healthy Italian preschool children using forced oscillations. We recommend a change in Z-score of -1.88 for R(rs8) and 2.48 for X(rs8) as cut-off values for a positive BDR.
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Affiliation(s)
- C Calogero
- Section of Respiratory Medicine, Department of Paediatrics, University of Florence, Anna Meyer University Hospital for Children, Florence, Italy.
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Abstract
Specific knowledge on paediatric physiology and adapted material are necessary to perform pulmonary function testing (PFT) with reliable results in young children (2-6 years). During this age period, although co-operation is minimal, successful testing data can greatly be enhanced because of team experience and motivation. A range of equipment able to measure resistance and spirometry is now widely available, but technical issues have to be considered before its use in young children. In this review, we detail equipment, data collection, reference values and clinical applications for resistance measurements (forced oscillation technique, interrupter technique and plethysmography) and spirometry. All these non-invasive techniques can be easily repeated in order to monitor treatment and lung development in congenital and early-acquired respiratory diseases.
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Affiliation(s)
- Nicole Beydon
- AP-HP Robert Debré Hospital, Functional Unit of Pulmonology, Paris, France.
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Current World Literature. Curr Opin Allergy Clin Immunol 2009; 9:177-84. [DOI: 10.1097/aci.0b013e328329f9ca] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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