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Bayat S. [Respiratory oscillometry: Theoretical foundations and clinical applications]. Rev Mal Respir 2024; 41:593-604. [PMID: 39174416 DOI: 10.1016/j.rmr.2024.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 07/22/2024] [Indexed: 08/24/2024]
Abstract
Oscillometry measures the mechanical properties of the respiratory system. As they are carried out during spontaneous breathing, oscillometry measurements do not require forced breathing maneuvers or the patient's active cooperation. The technique is complementary to conventional pulmonary function testing methods for the investigation of respiratory function, diagnosis and monitoring of respiratory diseases, and assessment of response to treatment. The present review aims to describe the theoretical foundations and practical methodology of oscillometry. It describes the gaps in scientific evidence regarding its clinical utility, and provides examples of current research and clinical applications.
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Affiliation(s)
- S Bayat
- Unité d'explorations fonctionnelles cardiorespiratoires, service de pneumologie et physiologie, CHU Grenoble Alpes, Grenoble, France; STROBE, Inserm UA07, université Grenoble Alpes, Grenoble, France.
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2
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Belousova N, Cheng A, Matelski J, Vasileva A, Wu JKY, Ghany R, Martinu T, Ryan CM, Chow CW. Effects of donor smoking history on early post-transplant lung function measured by oscillometry. Front Med (Lausanne) 2024; 11:1328395. [PMID: 38654829 PMCID: PMC11037252 DOI: 10.3389/fmed.2024.1328395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 03/22/2024] [Indexed: 04/26/2024] Open
Abstract
Introduction Prior studies assessing outcomes of lung transplants from cigarette-smoking donors found mixed results. Oscillometry, a non-invasive test of respiratory impedance, detects changes in lung function of smokers prior to diagnosis of COPD, and identifies spirometrically silent episodes of rejection post-transplant. We hypothesise that oscillometry could identify abnormalities in recipients of smoking donor lungs and discriminate from non-smoking donors. Methods This prospective single-center cohort study analysed 233 double-lung recipients. Oscillometry was performed alongside routine conventional pulmonary function tests (PFT) post-transplant. Multivariable regression models were constructed to compare oscillometry and conventional PFT parameters between recipients of lungs from smoking vs non-smoking donors. Results The analysis included 109 patients who received lungs from non-smokers and 124 from smokers. Multivariable analysis identified significant differences between recipients of smoking and non-smoking lungs in the oscillometric measurements R5-19, X5, AX, R5z and X5z, but no differences in %predicted FEV1, FEV1/FVC, %predicted TLC or %predicted DLCO. An analysis of the smoking group also demonstrated associations between increasing smoke exposure, quantified in pack years, and all the oscillometry parameters, but not the conventional PFT parameters. Conclusion An interaction was identified between donor-recipient sex match and the effect of smoking. The association between donor smoking and oscillometry outcomes was significant predominantly in the female donor/female recipient group.
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Affiliation(s)
- Natalia Belousova
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Program and Division of Respirology, University Health Network, Tonronto, ON, Canada
- Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Pneumology, Aduch Cystic Fibrosis and Lung Transplantation Department, Foch Hospital, Suresnes, France
| | - Albert Cheng
- Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - John Matelski
- Pneumology, Aduch Cystic Fibrosis and Lung Transplantation Department, Foch Hospital, Suresnes, France
| | - Anastasiia Vasileva
- Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Joyce K. Y. Wu
- Toronto General Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
| | - Rasheed Ghany
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Program and Division of Respirology, University Health Network, Tonronto, ON, Canada
| | - Tereza Martinu
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Program and Division of Respirology, University Health Network, Tonronto, ON, Canada
- Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Clodagh M. Ryan
- Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto General Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
| | - Chung-Wai Chow
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Program and Division of Respirology, University Health Network, Tonronto, ON, Canada
- Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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Crowhurst TD, Butler JA, Bussell LA, Johnston SD, Yeung D, Hodge G, Snell GI, Yeo A, Holmes M, Holmes-Liew CL. Impulse Oscillometry Versus Spirometry to Detect Bronchiolitis Obliterans Syndrome in Bilateral Lung Transplant Recipients: A Prospective Diagnostic Study. Transplantation 2024; 108:1004-1014. [PMID: 38044496 DOI: 10.1097/tp.0000000000004868] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
BACKGROUND Chronic lung allograft dysfunction (CLAD), and especially bronchiolitis obliterans syndrome (BOS), remain dominant causes of morbidity and mortality after lung transplantation. Interest is growing in the forced oscillation technique, of which impulse oscillometry (IOS) is a form, as a tool to improve our understanding of these disorders. However, data remain limited and no longitudinal studies have been published, meaning there is no information regarding any capacity IOS may have for the early detection of CLAD. METHODS We conducted a prospective longitudinal study enrolling a consecutive sample of adult bilateral lung transplant recipients with healthy lung allografts or CLAD and performed ongoing paired IOS and spirometry tests on a clinically determined basis. We assessed for correlations between IOS and spirometry and examined any predictive value either modality may hold for the early detection of BOS. RESULTS We enrolled 91 patients and conducted testing for 43 mo, collecting 558 analyzable paired IOS and spirometry tests, with a median of 9 tests per subject (interquartile range, 5-12) and a median testing interval of 92 d (interquartile range, 62-161). Statistically significant moderate-to-strong correlations were demonstrated between all IOS parameters and spirometry, except resistance at 20 Hz, which is a proximal airway measure. No predictive value for the early detection of BOS was found for IOS or spirometry. CONCLUSIONS This study presents the first longitudinal data from IOS after lung transplantation and adds considerably to the growing literature, showing unequivocal correlations with spirometry but failing to demonstrate a predictive value for BOS.
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Affiliation(s)
- Thomas D Crowhurst
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia
- Department of Haematology, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Jessica A Butler
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Lauren A Bussell
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Sonya D Johnston
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - David Yeung
- Department of Haematology, Royal Adelaide Hospital, Adelaide, SA, Australia
- Lung Transplant Service, The Alfred, Melbourne, VIC, Australia
| | - Greg Hodge
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia
- Department of Haematology, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Greg I Snell
- School of Medicine, Monash University, Melbourne, VIC, Australia
- SA Lung Transplant Unit, Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Aeneas Yeo
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, SA, Australia
- Department of Haematology, Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Mark Holmes
- Department of Haematology, Royal Adelaide Hospital, Adelaide, SA, Australia
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Chien-Li Holmes-Liew
- Department of Haematology, Royal Adelaide Hospital, Adelaide, SA, Australia
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
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Parekh KR. Impulse Oscillometry for Lung Transplant: Is It Good Enough? Transplantation 2024; 108:843-844. [PMID: 38044491 PMCID: PMC10963162 DOI: 10.1097/tp.0000000000004869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Affiliation(s)
- Kalpaj R. Parekh
- Department of Cardiothoracic Surgery, Carver College of Medicine, University of Iowa, Iowa City, IA
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Wu JK, Xu JJN, Vasileva A, Nohra C, Binnie M, Shapera S, Fisher JH, Ryan CM, McInnis M, Hantos Z, Chow CW. Respiratory oscillometry with CT image analysis in idiopathic pulmonary fibrosis following single lung transplant. Respir Med Case Rep 2024; 49:102016. [PMID: 38559325 PMCID: PMC10973643 DOI: 10.1016/j.rmcr.2024.102016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 03/14/2024] [Accepted: 03/18/2024] [Indexed: 04/04/2024] Open
Abstract
Oscillometry is an emerging pulmonary function testing tool that is conducted during tidal breaths with minimal patient effort. It is highly sensitive to changes in lung mechanics. Oscillometry was recently shown to be highly associated with disease severity in idiopathic pulmonary fibrosis (IPF). The usefulness of oscillometry after single lung transplant in IPF patients is not well understood. Our study demonstrated that oscillometry can detect changes in the graft despite presence of a native fibrotic lung to provide useful information to complement spirometry.
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Affiliation(s)
- Joyce K.Y. Wu
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
- Toronto General-Pulmonary Function Laboratory, University Health Network, Toronto, Canada
| | - Jessica Jia-Ni Xu
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
| | - Anastasiia Vasileva
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
| | - Cynthia Nohra
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
| | - Matthew Binnie
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
- Toronto Lung Transplant Program, University Health Network, Toronto, Canada
- Interstitial Lung Disease Program, University Health Network, Toronto, Canada
| | - Shane Shapera
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
- Interstitial Lung Disease Program, University Health Network, Toronto, Canada
| | - Jolene H. Fisher
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
- Interstitial Lung Disease Program, University Health Network, Toronto, Canada
| | - Clodagh M. Ryan
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
- Toronto General-Pulmonary Function Laboratory, University Health Network, Toronto, Canada
| | - Micheal McInnis
- Joint Department of Medical Imaging, University Health Network, Toronto, Canada
| | - Zoltán Hantos
- Department of Anesthesiology and Intensive Therapy, Semmelweis University, Budapest, Hungary
| | - Chung-Wai Chow
- Division of Respirology, Department of Medicine, University of Toronto, Toronto, Canada
- Toronto Lung Transplant Program, University Health Network, Toronto, Canada
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Aitken CR, Pathangey G, Stamos M, Kim CH, Johnson BD, Stewart GM. Reproducibility and responsiveness of airway impedance measures derived from the forced oscillation technique across different operating lung volumes. Respir Physiol Neurobiol 2024; 320:104200. [PMID: 38036081 DOI: 10.1016/j.resp.2023.104200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 11/21/2023] [Accepted: 11/22/2023] [Indexed: 12/02/2023]
Abstract
BACKGROUND The forced oscillation technique (FOT) enables non-invasive measurement of respiratory system impedance. Limited data exists on how changes in operating lung volume (OLV) impact FOT-derived measures of airway resistance (Rrs) and reactance (Xrs). OBJECTIVES This study examined the reproducibility and responsiveness of FOT-derived measures of Rrs and Xrs during simulated changes in OLV. METHODS Participants simulated breathing at six OLVs: total lung capacity (TLC), ∼50% of inspiratory reserve volume (IRV50), ∼two-times tidal volume (VT2), tidal volume (VT), ∼50% of expiratory reserve volume (ERV50), and residual volume (RV), on a commercially available FOT device. Each simulated OLV manuever was performed in triplicate and in random order. Total Rrs and Xrs were recorded at 5, 11, and 19 Hz. RESULTS Twelve healthy participants (2 female) completed the study (weight: 76.5 ± 13.6 kg, height: 178.6 ± 9.7 cm, body mass index: 23.9 ± 3.1 kg/m2). Reproducibility of Rrs and Xrs at VT, VT2 and IRV50 was good to excellent (Range: ICC: 0.89-0.98, 95% confidence interval (CI): 0.70-0.98), while reproducibility at TLC, RV, and ERV50 was poor to excellent (Range: ICC: 0.60-0.98, 95% CI: 0.36-0.97). Rrs and Xrs were not different between VT and VT2 at any frequency (P > .05). With lung hyperinflation from VT to TLC, Rrs and Xrs decreased at all three frequencies (e.g., At 5 Hz Rrs: mean difference (MD): - 0.89, 95%CI: - 0.03 to - 1.75, P = .04; Xrs: MD: - 0.56, 95%CI: - 0.25 to - 0.86, P < .01). With lung hypoinflated from VT to RV, Rrs increased, and Xrs decreased for all frequencies (e.g., MD at 5 Hz, Rrs: MD: 2.31, 95%CI: 0.94-3.67, P < .01; Xrs: MD: -2.53, 95%CI: -4.02 to -1.04, P < .01). CONCLUSION FOT-derived measures of airway Rrs and Xrs are reproducible across a range of OLV's, and are responsive to hyper- and hypo-inflation of the lung. To further understand the impact of lung hyper- and hypo-inflation on FOT-derived airway impedance additional study is required in individuals with pathological variations in operating lung volume.
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Affiliation(s)
- Craig R Aitken
- Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | | | - Mathew Stamos
- Depatment of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Chul-Ho Kim
- Depatment of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Bruce D Johnson
- Depatment of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Glenn M Stewart
- Depatment of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA; Charles Perkins Centre and School of Medicine, Faculty of Medicine and Health, University of Sydney, Camberdown, NSW, Australia.
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Sim JPY, Nilsen K, Borg BM, Levvey B, Vazirani J, Ennis S, Plit M, Snell GI, Darley DR, Tonga KO. Oscillometry in Stable Single and Double Lung Allograft Recipients Transplanted for Interstitial Lung Disease: Results of a Multi-Center Australian Study. Transpl Int 2023; 36:11758. [PMID: 38116170 PMCID: PMC10728296 DOI: 10.3389/ti.2023.11758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 11/14/2023] [Indexed: 12/21/2023]
Abstract
Peak spirometry after single lung transplantation (SLTx) for interstitial lung disease (ILD) is lower than after double lung transplantation (DLTx), however the pathophysiologic mechanisms are unclear. We aim to assess respiratory mechanics in SLTx and DLTx for ILD using oscillometry. Spirometry and oscillometry (tremoflo® C-100) were performed in stable SLTx and DLTx recipients in a multi-center study. Resistance (R5, R5-19) and reactance (X5) were compared between LTx recipient groups, matched by age and gender. A model of respiratory impedance using ILD and DLTx data was performed. In total, 45 stable LTx recipients were recruited (SLTx n = 23, DLTx n = 22; males: 87.0% vs. 77.3%; median age 63.0 vs. 63.0 years). Spirometry was significantly lower after SLTx compared with DLTx: %-predicted mean (SD) FEV1 [70.0 (14.5) vs. 93.5 (26.0)%]; FVC [70.5 (16.8) vs. 90.7 (12.8)%], p < 0.01. R5 and R5-19 were similar between groups (p = 0.94 and p = 0.11, respectively) yet X5 was significantly worse after SLTx: median (IQR) X5 [-1.88 (-2.89 to -1.39) vs. -1.22 (-1.87 to -0.86)] cmH2O.s/L], p < 0.01. R5 and X5 measurements from the model were congruent with measurements in SLTx recipients. The similarities in resistance, yet differences in spirometry and reactance between both transplant groups suggest the important contribution of elastic properties to the pathophysiology. Oscillometry may provide further insight into the physiological changes occurring post-LTx.
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Affiliation(s)
- Joan P. Y. Sim
- Lung Transplant and Thoracic Medicine Unit, St Vincent’s Hospital, Sydney, NSW, Australia
- St Vincent’s Hospital Clinical Campus, Faculty of Medicine and Health, The University of New South Wales, Sydney, NSW, Australia
| | - Kristopher Nilsen
- Lung Transplant and Respiratory Medicine Service, The Alfred Hospital, Melbourne, VIC, Australia
| | - Brigitte M. Borg
- Lung Transplant and Respiratory Medicine Service, The Alfred Hospital, Melbourne, VIC, Australia
- School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Bronwyn Levvey
- Lung Transplant and Respiratory Medicine Service, The Alfred Hospital, Melbourne, VIC, Australia
- Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, VIC, Australia
| | - Jaideep Vazirani
- Lung Transplant and Respiratory Medicine Service, The Alfred Hospital, Melbourne, VIC, Australia
| | - Samantha Ennis
- Lung Transplant and Respiratory Medicine Service, The Alfred Hospital, Melbourne, VIC, Australia
| | - Marshall Plit
- Lung Transplant and Thoracic Medicine Unit, St Vincent’s Hospital, Sydney, NSW, Australia
- St Vincent’s Hospital Clinical Campus, Faculty of Medicine and Health, The University of New South Wales, Sydney, NSW, Australia
| | - Gregory I. Snell
- Lung Transplant and Respiratory Medicine Service, The Alfred Hospital, Melbourne, VIC, Australia
- Faculty of Medicine, Nursing and Health Science, Monash University, Melbourne, VIC, Australia
| | - David R. Darley
- Lung Transplant and Thoracic Medicine Unit, St Vincent’s Hospital, Sydney, NSW, Australia
- St Vincent’s Hospital Clinical Campus, Faculty of Medicine and Health, The University of New South Wales, Sydney, NSW, Australia
| | - Katrina O. Tonga
- Lung Transplant and Thoracic Medicine Unit, St Vincent’s Hospital, Sydney, NSW, Australia
- St Vincent’s Hospital Clinical Campus, Faculty of Medicine and Health, The University of New South Wales, Sydney, NSW, Australia
- Northern Clinical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
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Sonneveld N, Rayment JH, Usemann J, Nielsen KG, Robinson PD. Multiple breath washout and oscillometry after allogenic HSCT: a scoping review. Eur Respir Rev 2023; 32:220251. [PMID: 37495248 PMCID: PMC10369167 DOI: 10.1183/16000617.0251-2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 05/04/2023] [Indexed: 07/28/2023] Open
Abstract
Pulmonary chronic graft-versus-host disease (cGVHD) is a substantial cause of pulmonary morbidity and mortality post-haematopoietic stem cell transplantation (HSCT). Current spirometry-based monitoring strategies have significant limitations. Understanding the utility of novel peripheral airway function tests - multiple breath washout (MBW) and oscillometry - is critical in efforts to improve detection, facilitate earlier intervention and improve outcomes. In this scoping review, we identified 17 studies investigating MBW or oscillometry, or both, after allogenic HSCT. Despite small study numbers limiting the ability to draw firm conclusions, several themes were evident. Detectable peripheral airway abnormality in MBW occurred in a substantial proportion prior to HSCT. MBW indices post-HSCT were more frequently abnormal than spirometry when reporting group data and among those with extrapulmonary cGVHD and pulmonary cGVHD. Changes in MBW indices over time may be more indicative of pulmonary complications than absolute values at any given time point. Oscillometry indices were often normal at baseline, but more frequently abnormal in those who developed pulmonary cGVHD. Pooling currently available individual participant data across these studies may improve our ability to formally compare their respective sensitivity and specificity at specific time points and assess the trajectory of MBW and oscillometry indices over time.
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Affiliation(s)
- Nicole Sonneveld
- Department of Respiratory Medicine, Children's Hospital at Westmead, Sydney Children's Hospitals Network, Sydney, Australia
- Discipline of Paediatrics and Child Health, University of Sydney, Sydney, Australia
| | - Jonathan H Rayment
- Division of Respiratory Medicine, Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada
- BC Children's Hospital Research Institute, Vancouver, BC, Canada
| | - Jakob Usemann
- University Children's Hospital Basel (UKBB), Basel, Switzerland
- Division of Respiratory Medicine and Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Kim G Nielsen
- Paediatric Pulmonary Service, Copenhagen University Hospital, Department of Paediatric and Adolescent Medicine, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Paul D Robinson
- Department of Respiratory Medicine, Children's Hospital at Westmead, Sydney Children's Hospitals Network, Sydney, Australia
- Discipline of Paediatrics and Child Health, University of Sydney, Sydney, Australia
- Airway Physiology and Imaging Group, The Woolcock Institute of Medical Research, Sydney, Australia
- Children's Health and Environment Program, Child Health Research Centre, University of Queensland, Brisbane, Australia
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Vasileva A, Hanafi N, Huszti E, Matelski J, Belousova N, Wu JKY, Martinu T, Ghany R, Keshavjee S, Tikkanen J, Cypel M, Yeung JC, Ryan CM, Chow CW. Intra-subject variability in oscillometry correlates with acute rejection and CLAD post-lung transplant. Front Med (Lausanne) 2023; 10:1158870. [PMID: 37305133 PMCID: PMC10248398 DOI: 10.3389/fmed.2023.1158870] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/04/2023] [Indexed: 06/13/2023] Open
Abstract
Background Chronic lung allograft dysfunction (CLAD) is the major cause of death post-lung transplantation, with acute cellular rejection (ACR) being the biggest contributing risk factor. Although patients are routinely monitored with spirometry, FEV1 is stable or improving in most ACR episodes. In contrast, oscillometry is highly sensitive to respiratory mechanics and shown to track graft injury associated with ACR and its improvement following treatment. We hypothesize that intra-subject variability in oscillometry measurements correlates with ACR and risk of CLAD. Methods Of 289 bilateral lung recipients enrolled for oscillometry prior to laboratory-based spirometry between December 2017 and March 2020, 230 had ≥ 3 months and 175 had ≥ 6 months of follow-up. While 37 patients developed CLAD, only 29 had oscillometry at time of CLAD onset and were included for analysis. These 29 CLAD patients were time-matched with 129 CLAD-free recipients. We performed multivariable regression to investigate the associations between variance in spirometry/oscillometry and the A-score, a cumulative index of ACR, as our predictor of primary interest. Conditional logistic regression models were built to investigate associations with CLAD. Results Multivariable regression showed that the A-score was positively associated with the variance in oscillometry measurements. Conditional logistic regression models revealed that higher variance in the oscillometry metrics of ventilatory inhomogeneity, X5, AX, and R5-19, was independently associated with increased risk of CLAD (p < 0.05); no association was found for variance in %predicted FEV1. Conclusion Oscillometry tracks graft injury and recovery post-transplant. Monitoring with oscillometry could facilitate earlier identification of graft injury, prompting investigation to identify treatable causes and decrease the risk of CLAD.
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Affiliation(s)
- Anastasiia Vasileva
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Nour Hanafi
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Ella Huszti
- Biostatistics Research Unit, University Health Network, Toronto, ON, Canada
| | - John Matelski
- Biostatistics Research Unit, University Health Network, Toronto, ON, Canada
| | - Natalia Belousova
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Joyce K. Y. Wu
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
| | - Tereza Martinu
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Rasheed Ghany
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Shaf Keshavjee
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
- Division of Thoracic Surgery, Department of Surgery, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Jussi Tikkanen
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Marcelo Cypel
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
- Division of Thoracic Surgery, Department of Surgery, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Jonathan C. Yeung
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
- Division of Thoracic Surgery, Department of Surgery, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Clodagh M. Ryan
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
| | - Chung-Wai Chow
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
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10
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Rozenberg D, Al Kaabi N, Camacho Perez E, Nourouzpour S, Lopez-Hernandez L, McGillis L, Goligher E, Reid WD, Chow CW, Ryan CM, Kumbhare D, Huszti E, Champagne K, Raj S, Mak S, Santa Mina D, Clarke H, Mittal N. Evaluation and Management of Dyspnea in Hypermobile Ehlers-Danlos Syndrome and Generalized Hypermobility Spectrum Disorder: Protocol for a Pilot and Feasibility Randomized Controlled Trial. JMIR Res Protoc 2023; 12:e44832. [PMID: 36939815 PMCID: PMC10131980 DOI: 10.2196/44832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Dyspnea is a prevalent symptom in individuals with hypermobile Ehlers-Danlos Syndrome (hEDS) and generalized hypermobility spectrum disorder (G-HSD), yet its contributors have not been identified. One known contributor to dyspnea is respiratory muscle weakness. The feasibility and effectiveness of inspiratory muscle training (IMT) in combination with standard-of-care rehabilitation (aerobic, resistance, neuromuscular stabilization, and balance and proprioception exercises) in improving respiratory muscle strength and patient-reported outcomes in patients with hEDS or G-HSD have not been evaluated. OBJECTIVE This study aims to evaluate dyspnea, respiratory muscle strength, and patient-reported outcome measures (PROMs) in hEDS or G-HSD compared with healthy controls and to assess the feasibility of a randomized controlled trial of IMT and standard-of-care rehabilitation for improving respiratory muscle strength, exercise capacity, and PROMs compared with standard-of-care rehabilitation in hEDS and G-HSD. METHODS The study will include 34 participants with hEDS or G-HSD and 17 healthy, age- and sex-matched controls to compare respiratory muscle structure and function and PROMs. After baseline assessments, participants with hEDS or G-HSD will be randomized into the intervention group and provided IMT combined with Ehlers-Danlos Syndrome standard-of-care rehabilitation or into the usual care group, and provided only standard-of-care rehabilitation for 8 weeks. The intervention group will be prescribed IMT in their home environment using the POWERbreathe K5 IMT device (POWERbreathe International Ltd). IMT will comprise 2 daily sessions of 30 breaths for 5 days per week, with IMT progressing from 20% to 60% of the baseline maximal inspiratory pressure (MIP) over an 8-week period. Feasibility will be assessed through rates of recruitment, attrition, adherence, adverse events, and participant satisfaction. The primary pilot outcome is MIP change over an 8-week period in hEDS or G-HSD. Secondary outcomes will include the evaluation of dyspnea using Medical Research Council Scale and 18-point qualitative dyspnea descriptors; diaphragmatic thickening fraction using ultrasound; respiratory muscle endurance; pulmonary function; prefrontal cortical activity using functional near-infrared spectroscopy; aerobic capacity during cardiopulmonary exercise testing; quality of life using Short Form-36; and scores from the Depression, Anxiety, and Stress scale-21. These measures will also be performed once in healthy controls to compare normative values. Multivariable regression will be used to assess the contributors to dyspnea. Paired 2-tailed t tests will be used to assess the changes in MIP and secondary measures after 8 weeks of IMT. RESULTS Study recruitment began in August 2021 and, with several disruptions owing to COVID-19, is expected to be completed by December 2023. CONCLUSIONS This study will provide a better understanding of the factors associated with dyspnea and the feasibility and effectiveness of IMT combined with standard-of-care rehabilitation. IMT may be a novel therapeutic strategy for improving respiratory muscle function and patient-reported outcomes in individuals with hEDS or G-HSD. TRIAL REGISTRATION ClinicalTrials.gov NCT04972565; https://clinicaltrials.gov/ct2/show/NCT04972565. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/44832.
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Affiliation(s)
- Dmitry Rozenberg
- Respirology and Lung Transplantation, Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
- Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- GoodHope Ehlers-Danlos Syndrome Clinic, University Health Network, Toronto, ON, Canada
| | - Noor Al Kaabi
- Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- GoodHope Ehlers-Danlos Syndrome Clinic, University Health Network, Toronto, ON, Canada
- Respirology, Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
| | - Encarna Camacho Perez
- GoodHope Ehlers-Danlos Syndrome Clinic, University Health Network, Toronto, ON, Canada
- Respirology, Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
| | - Sahar Nourouzpour
- Respirology, Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
| | - Laura Lopez-Hernandez
- GoodHope Ehlers-Danlos Syndrome Clinic, University Health Network, Toronto, ON, Canada
| | - Laura McGillis
- GoodHope Ehlers-Danlos Syndrome Clinic, University Health Network, Toronto, ON, Canada
| | - Ewan Goligher
- Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Respirology, Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
| | - W Darlene Reid
- KITE-Toronto Rehab, University Health Network, Toronto, ON, Canada
- Physical Therapy, University of Toronto, Toronto, ON, Canada
| | - Chung-Wai Chow
- Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Respirology, Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
| | - Clodagh M Ryan
- KITE-Toronto Rehab, University Health Network, Toronto, ON, Canada
| | - Dinesh Kumbhare
- Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- KITE-Toronto Rehab, University Health Network, Toronto, ON, Canada
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Ella Huszti
- Biostatistics Research Unit, University Health Network, Toronto, ON, Canada
| | | | - Satish Raj
- Department of Cardiac Sciences, Cumming School of Medicine, Calgary, AB, Canada
| | - Susanna Mak
- Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Department of Cardiology, Mount Sinai Hospital, Toronto, ON, Canada
| | - Daniel Santa Mina
- GoodHope Ehlers-Danlos Syndrome Clinic, University Health Network, Toronto, ON, Canada
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia and Pain Management, University Health Network, Toronto, ON, Canada
| | - Hance Clarke
- Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- GoodHope Ehlers-Danlos Syndrome Clinic, University Health Network, Toronto, ON, Canada
- Department of Anesthesia and Pain Management, University Health Network, Toronto, ON, Canada
| | - Nimish Mittal
- Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- GoodHope Ehlers-Danlos Syndrome Clinic, University Health Network, Toronto, ON, Canada
- KITE-Toronto Rehab, University Health Network, Toronto, ON, Canada
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
- Department of Anesthesia and Pain Management, University Health Network, Toronto, ON, Canada
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11
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Beeckmans H, Bos S, Vos R, Glanville AR. Acute Rejection and Chronic Lung Allograft Dysfunction: Obstructive and Restrictive Allograft Dysfunction. Clin Chest Med 2023; 44:137-157. [PMID: 36774160 DOI: 10.1016/j.ccm.2022.10.011] [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: 02/11/2023]
Abstract
Lung transplantation is an established treatment of well-selected patients with end-stage respiratory diseases. However, lung transplant recipients have the highest rates of acute and chronic rejection among transplanted solid organs. Owing to ongoing alloimmune recognition and associated immune-driven airway/vascular remodeling, precipitated by multifactorial, endogenous or exogenous, post-transplant injuries to the bronchovascular axis of the secondary pulmonary lobule, most lung transplant recipients will suffer from a pathophysiological decline of their allograft, either functionally and/or structurally. This review discusses current knowledge, barriers, and gaps in acute cellular rejection and chronic lung allograft dysfunction-the greatest impediment to long-term post-transplant survival.
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Affiliation(s)
- Hanne Beeckmans
- Department of Chronic Diseases and Metabolism, KU Leuven, Laboratory of Respiratory Diseases and Thoracic Surgery (BREATHE), Leuven, Belgium
| | - Saskia Bos
- Department of Respiratory Diseases, University Hospitals Leuven, Leuven, Belgium; Newcastle University, Translational and Clinical Research Institute, Newcastle upon Tyne, UK
| | - Robin Vos
- Department of Chronic Diseases and Metabolism, KU Leuven, Laboratory of Respiratory Diseases and Thoracic Surgery (BREATHE), Leuven, Belgium; Department of Respiratory Diseases, University Hospitals Leuven, Leuven, Belgium.
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12
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Darley DR, Nilsen K, Vazirani J, Borg BM, Levvey B, Snell G, Plit ML, Tonga KO. Airway oscillometry parameters in baseline lung allograft dysfunction: Associations from a multicenter study. J Heart Lung Transplant 2023; 42:767-777. [PMID: 36681528 DOI: 10.1016/j.healun.2022.12.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 12/09/2022] [Accepted: 12/30/2022] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Baseline lung allograft dysfunction (BLAD), the failure to achieve ≥80%-predicted spirometry after lung transplant (LTx), is associated with impaired survival. Physiologic abnormalities in BLAD are poorly understood. Airway oscillometry measures respiratory system mechanics and may provide insight into understanding the mechanisms of BLAD. OBJECTIVES This study aims to describe and measure the association between airway oscillometry parameters [Reactance (Xrs5, Ax), Resistance (Rrs5, Rrs5-19)] (1) stable LTx recipients, comparing those with normal spirometry and those with BLAD; and (2) in recipients with chronic lung allograft dysfunction (CLAD), comparing those with normal baseline spirometry and those with BLAD. METHODS A multi-center cross-sectional study was performed including bilateral LTx between January 2020 and June 2021. Participants performed concurrent airway oscillometry and spirometry. Multivariable logistic regression was performed to measure the association between oscillometry parameters and BLAD. RESULTS A total of 404 LTx recipients performed oscillometry and 253 were included for analysis. Stable allograft function was confirmed in 149 (50.2%) recipients (92 (61.7%) achieving normal spirometry and 57 (38.3%) with BLAD). Among stable LTx recipients, lower Xrs5 Z-Score (aOR 0.50 95% CI 0.37-0.76, p = 0.001) was independently associated with BLAD. CLAD was present in 104 (35.0%) recipients. Among recipients with CLAD, lower Xrs5 Z-Score (aOR 0.73 95% CI 0.56-0.95, p = 0.02) was associated with BLAD. CONCLUSIONS Oscillometry provides novel physiologic insights into mechanisms of BLAD. The independent association between Xrs5 and BLAD, in both stable recipients and those with CLAD suggests that respiratory mechanics, in particular abnormal elastance, is an important physiologic feature. Further longitudinal studies are needed to understand the trajectory of oscillometry parameters in relation to allograft outcomes.
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Affiliation(s)
- David Ross Darley
- Lung Transplant Unit, St Vincent's Hospital Sydney, Darlinghurst NSW, Australia; School of Clinical Medicine, St Vincent's Healthcare Clinical Campus, UNSW Medicine & Health, UNSW Sydney, Australia.
| | - Kris Nilsen
- Lung Transplant Service, The Alfred Hospital, Melbourne, Australia
| | - Jaideep Vazirani
- Lung Transplant Service, The Alfred Hospital, Melbourne, Australia
| | - Brigitte M Borg
- Respiratory Medicine, The Alfred Hospital, Melbourne, Australia
| | - Bronwyn Levvey
- Lung Transplant Service, The Alfred Hospital, Melbourne, Australia
| | - G Snell
- Lung Transplant Service, The Alfred Hospital, Melbourne, Australia
| | - Marshall Lawrence Plit
- Lung Transplant Unit, St Vincent's Hospital Sydney, Darlinghurst NSW, Australia; School of Clinical Medicine, St Vincent's Healthcare Clinical Campus, UNSW Medicine & Health, UNSW Sydney, Australia
| | - Katrina O Tonga
- School of Clinical Medicine, St Vincent's Healthcare Clinical Campus, UNSW Medicine & Health, UNSW Sydney, Australia; Thoracic Medicine Department, St Vincent's Hospital Darlinghurst, Sydney, Australia; Northern Clinical School, Sydney Medical School, Faculty of Medicine & Health, University of Sydney, Sydney, Australia
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13
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Fu A, Vasileva A, Hanafi N, Belousova N, Wu J, Rajyam SS, Ryan CM, Hantos Z, Chow CW. Characterization of chronic lung allograft dysfunction phenotypes using spectral and intrabreath oscillometry. Front Physiol 2022; 13:980942. [PMID: 36277208 PMCID: PMC9582781 DOI: 10.3389/fphys.2022.980942] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Chronic lung allograft dysfunction (CLAD) is the major cause of death beyond 2 years after lung transplantation and develops in 50% of all patients by 5 years post-transplant. CLAD is diagnosed on the basis of a sustained drop of 20% for at least 3 months in the forced expiratory volume (FEV1), compared to the best baseline value achieved post-transplant. CLAD presents as two main phenotypes: bronchiolitis obliterans syndrome (BOS) is more common and has better prognosis than restrictive allograft syndrome (RAS). Respiratory oscillometry is a different modality of lung function testing that is highly sensitive to lung mechanics. The current study investigated whether spectral and intrabreath oscillometry can differentiate between CLAD-free, BOS- and RAS-CLAD at CLAD onset, i.e., at the time of the initial 20% drop in the FEV1. Methods: A retrospective, cross-sectional analysis of 263 double lung transplant recipients who underwent paired testing with oscillometry and spirometry at the Toronto General Pulmonary Function Laboratory from 2017 to 2022 was conducted. All pulmonary function testing and CLAD diagnostics were performed following international guidelines. Statistical analysis was conducted using multiple comparisons. Findings: The RAS (n = 6) spectral oscillometry pattern differs from CLAD-free (n = 225) by right-ward shift of reactance curve similar to idiopathic pulmonary fibrosis whereas BOS (n = 32) has a pattern similar to obstructive lung disease. Significant differences were found in most spectral and intrabreath parameters between BOS, RAS, and time-matched CLAD-free patients. Post-hoc analysis revealed these differences were primarily driven by BOS instead of RAS. While no differences were found between CLAD-free and RAS patients with regards to spectral oscillometry, the intrabreath metric of reactance at end-inspiration (XeI) was significantly different (p < 0.05). BOS and RAS were differentiated by spectral oscillometry measure R5, and intrabreath resistance at end expiration, ReE (p < 0.05 for both). Conclusion: Both spectral and intrabreath oscillometry can differentiate BOS-CLAD from CLAD-free states while intrabreath oscillometry, specifically XeI, can uniquely distinguish RAS-CLAD from CLAD-free. Spectral and intrabreath oscillometry offer complementary information regarding lung mechanics in CLAD patients to help distinguish the two phenotypes and could prove useful in prognostication.
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Affiliation(s)
- Anne Fu
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Anastasiia Vasileva
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Nour Hanafi
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Natalia Belousova
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Joyce Wu
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto General Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
| | - Sarada Sriya Rajyam
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Clodagh M. Ryan
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto General Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
| | - Zoltán Hantos
- Department of Anesthesiology and Intensive Therapy, Semmelweis University, Budapest, Hungary
| | - Chung-Wai Chow
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
- Toronto General Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
- *Correspondence: Chung-Wai Chow,
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14
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Herminghaus A, Kozlov AV, Szabó A, Hantos Z, Gylstorff S, Kuebart A, Aghapour M, Wissuwa B, Walles T, Walles H, Coldewey SM, Relja B. A Barrier to Defend - Models of Pulmonary Barrier to Study Acute Inflammatory Diseases. Front Immunol 2022; 13:895100. [PMID: 35874776 PMCID: PMC9300899 DOI: 10.3389/fimmu.2022.895100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 06/20/2022] [Indexed: 12/04/2022] Open
Abstract
Pulmonary diseases represent four out of ten most common causes for worldwide mortality. Thus, pulmonary infections with subsequent inflammatory responses represent a major public health concern. The pulmonary barrier is a vulnerable entry site for several stress factors, including pathogens such as viruses, and bacteria, but also environmental factors e.g. toxins, air pollutants, as well as allergens. These pathogens or pathogen-associated molecular pattern and inflammatory agents e.g. damage-associated molecular pattern cause significant disturbances in the pulmonary barrier. The physiological and biological functions, as well as the architecture and homeostatic maintenance of the pulmonary barrier are highly complex. The airway epithelium, denoting the first pulmonary barrier, encompasses cells releasing a plethora of chemokines and cytokines, and is further covered with a mucus layer containing antimicrobial peptides, which are responsible for the pathogen clearance. Submucosal antigen-presenting cells and neutrophilic granulocytes are also involved in the defense mechanisms and counterregulation of pulmonary infections, and thus may directly affect the pulmonary barrier function. The detailed understanding of the pulmonary barrier including its architecture and functions is crucial for the diagnosis, prognosis, and therapeutic treatment strategies of pulmonary diseases. Thus, considering multiple side effects and limited efficacy of current therapeutic treatment strategies in patients with inflammatory diseases make experimental in vitro and in vivo models necessary to improving clinical therapy options. This review describes existing models for studyying the pulmonary barrier function under acute inflammatory conditions, which are meant to improve the translational approaches for outcome predictions, patient monitoring, and treatment decision-making.
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Affiliation(s)
- Anna Herminghaus
- Department of Anaesthesiology, University of Duesseldorf, Duesseldorf, Germany
| | - Andrey V. Kozlov
- L Boltzmann Institute for Traumatology in Cooperation with AUVA and Austrian Cluster for Tissue Regeneration, Vienna, Austria
- Department of Human Pathology , IM Sechenov Moscow State Medical University, Moscow, Russia
| | - Andrea Szabó
- Institute of Surgical Research, University of Szeged, Szeged, Hungary
| | - Zoltán Hantos
- Department of Anaesthesiology and Intensive Therapy, Semmelweis University, Budapest, Hungary
| | - Severin Gylstorff
- Experimental Radiology, Department of Radiology and Nuclear Medicine, Otto-von-Guericke University, Magdeburg, Germany
- Research Campus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany
| | - Anne Kuebart
- Department of Anaesthesiology, University of Duesseldorf, Duesseldorf, Germany
| | - Mahyar Aghapour
- Experimental Radiology, Department of Radiology and Nuclear Medicine, Otto-von-Guericke University, Magdeburg, Germany
| | - Bianka Wissuwa
- Department of Anaesthesiology and Intensive Care Medicine, Septomics Research Centre, Centre for Sepsis Control and Care, Jena University Hospital, Jena, Germany
| | - Thorsten Walles
- Department of Thoracic Surgery, Magdeburg University Medicine, Magdeburg, Germany
| | - Heike Walles
- Research Campus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany
- Core Facility Tissue Engineering, Otto-von-Guericke-University, Magdeburg, Germany
| | - Sina M. Coldewey
- Department of Anaesthesiology and Intensive Care Medicine, Septomics Research Centre, Centre for Sepsis Control and Care, Jena University Hospital, Jena, Germany
| | - Borna Relja
- Experimental Radiology, Department of Radiology and Nuclear Medicine, Otto-von-Guericke University, Magdeburg, Germany
- Research Campus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany
- *Correspondence: Borna Relja,
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15
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Wu JKY, Ma J, Nguyen L, Dehaas EL, Vasileva A, Chang E, Liang J, Huang QW, Cassano A, Binnie M, Shapera S, Fisher J, Ryan CM, McInnis MC, Hantos Z, Chow CW. Correlation of respiratory oscillometry with CT image analysis in a prospective cohort of idiopathic pulmonary fibrosis. BMJ Open Respir Res 2022; 9:9/1/e001163. [PMID: 35396320 PMCID: PMC8996008 DOI: 10.1136/bmjresp-2021-001163] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 03/28/2022] [Indexed: 11/10/2022] Open
Abstract
Background Markers of idiopathic pulmonary fibrosis (IPF) severity are based on measurements of forced vital capacity (FVC), diffusing capacity (DLCO) and CT. The pulmonary vessel volume (PVV) is a novel quantitative and independent prognostic structural indicator derived from automated CT analysis. The current prospective cross-sectional study investigated whether respiratory oscillometry provides complementary data to pulmonary function tests (PFTs) and is correlated with PVV. Methods From September 2019 to March 2020, we enrolled 89 patients with IPF diagnosed according to international guidelines. We performed standard spectral (5–37 Hz) and novel intrabreath tracking (10 Hz) oscillometry followed by PFTs. Patients were characterised with the gender-age-physiology (GAP) score. CT images within 6 months of oscillometry were analysed in a subgroup (26 patients) using automated lung texture analysis. Correlations between PFTs, oscillometry and imaging variables were investigated using different regression models. Findings The cohort (29F/60M; age=71.7±7.8 years) had mild IPF (%FVC=70±17, %DLCO=62±17). Spectral oscillometry revealed normal respiratory resistance, low reactance, especially during inspiration at 5 Hz (X5in), elevated reactance area and resonance frequency. Intrabreath oscillometry identified markedly low reactance at end-inspiration (XeI). XeI and X5in strongly correlated with FVC (r2=0.499 and 0.435) while XeI was highly (p=0.004) and uniquely correlated with the GAP score. XeI and PVV exhibited the strongest structural-functional relationship (r2=0.690), which remained significant after adjusting for %FVC, %DLCO and GAP score. Interpretation XeI is an independent marker of IPF severity that offers additional information to standard PFTs. The data provide a cogent rationale for adding oscillometry in IPF assessment.
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Affiliation(s)
- Joyce K Y Wu
- Department of Medicine, University Health Network, Toronto, Ontario, Canada
| | - Jin Ma
- Biostatistics Research Unit, University Health Network, Toronto, Ontario, Canada
| | - Lena Nguyen
- Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Emily Leah Dehaas
- Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Anastasiia Vasileva
- Department of Medicine, University Health Network, Toronto, Ontario, Canada.,Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Ehren Chang
- Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Jady Liang
- Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Qian Wen Huang
- Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Antonio Cassano
- Department of Medicine, University Health Network, Toronto, Ontario, Canada
| | - Matthew Binnie
- Department of Medicine, University Health Network, Toronto, Ontario, Canada.,Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Shane Shapera
- Department of Medicine, University Health Network, Toronto, Ontario, Canada.,Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Jolene Fisher
- Department of Medicine, University Health Network, Toronto, Ontario, Canada.,Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Clodagh M Ryan
- Department of Medicine, University Health Network, Toronto, Ontario, Canada.,Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
| | - Micheal Chad McInnis
- Joint Department of Medical Imaging, University of Toronto, Toronto, Ontario, Canada
| | - Zoltán Hantos
- Department of Anesthesiology and Intensive Therapy, Semmelweis University, Budapest, Hungary
| | - Chung-Wai Chow
- Department of Medicine, University Health Network, Toronto, Ontario, Canada .,Medicine, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, University of Toronto, Toronto, Ontario, Canada
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16
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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: 72] [Impact Index Per Article: 36.0] [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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17
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Rayment JH, Sandoval RA, Roden JP, Schultz KR. Multiple breath washout testing to identify pulmonary chronic graft versus host disease in children after haematopoietic stem cell transplantation. Transplant Cell Ther 2022; 28:328.e1-328.e7. [DOI: 10.1016/j.jtct.2022.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 10/19/2022]
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18
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Kouri A, Dandurand RJ, Usmani OS, Chow CW. Exploring the 175-year history of spirometry and the vital lessons it can teach us today. Eur Respir Rev 2021; 30:30/162/210081. [PMID: 34615699 DOI: 10.1183/16000617.0081-2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 07/02/2021] [Indexed: 12/25/2022] Open
Abstract
175 years have elapsed since John Hutchinson introduced the world to his version of an apparatus that had been in development for nearly two centuries, the spirometer. Though he was not the first to build a device that sought to measure breathing and quantify the impact of disease and occupation on lung function, Hutchison coined the terms spirometer and vital capacity that are still in use today, securing his place in medical history. As Hutchinson envisioned, spirometry would become crucial to our growing knowledge of respiratory pathophysiology, from Tiffeneau and Pinelli's work on forced expiratory volumes, to Fry and Hyatt's description of the flow-volume curve. In the 20th century, standardization of spirometry further broadened its reach and prognostic potential. Today, spirometry is recognized as essential to respiratory disease diagnosis, management and research. However, controversy exists in some of its applications, uptake in primary care remains sub-optimal and there are concerns related to the way in which race is factored into interpretation. Moving forward, these failings must be addressed, and innovations like Internet-enabled portable spirometers may present novel opportunities. We must also consider the physiologic and practical limitations inherent to spirometry and further investigate complementary technologies such as respiratory oscillometry and other emerging technologies that assess lung function. Through an exploration of the storied history of spirometry, we can better contextualize its current landscape and appreciate the trends that have repeatedly arisen over time. This may help to improve our current use of spirometry and may allow us to anticipate the obstacles confronting emerging pulmonary function technologies.
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Affiliation(s)
- Andrew Kouri
- Division of Respirology, Dept of Medicine, St. Michael's Hospital, Unity Health Toronto, Ontario, Canada
| | - Ronald J Dandurand
- Lakeshore General Hospital, Quebec, Canada.,Dept of Medicine, Respiratory Division, McGill University, Montreal, Quebec, Canada.,Montreal Chest Institute, Meakins-Christie Labs and Oscillometry Unit of the Centre for Innovative Medicine, McGill University Health Centre and Research Institute, Montreal, Canada
| | - Omar S Usmani
- National Heart and Lung Institute, Imperial College London and Royal Brompton Hospital, London, UK
| | - Chung-Wai Chow
- Dept of Medicine, University of Toronto, Toronto, Canada.,Division of Respirology and Multi-Organ Transplant Programme, Dept of Medicine, Toronto General Hospital, University Health Network, Toronto, Canada
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19
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Virji MA, Cummings KJ, Cox-Ganser JM. A Strategy for Field Evaluations of Exposures and Respiratory Health of Workers at Small- to Medium-Sized Coffee Facilities. Front Public Health 2021; 9:705225. [PMID: 34858915 PMCID: PMC8631862 DOI: 10.3389/fpubh.2021.705225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 10/13/2021] [Indexed: 11/13/2022] Open
Abstract
Coffee production is a global industry with roasteries throughout the world. Workers in this industry are exposed to complex mixtures of gases, dusts, and vapors including carbon monoxide, carbon dioxide, coffee dust, allergens, alpha-diketones, and other volatile organic compounds (VOCs). Adverse respiratory health outcomes such as respiratory symptoms, reduced pulmonary function, asthma, and obliterative bronchiolitis can occur among exposed workers. In response to health hazard evaluations requests received from 17 small- to medium-sized coffee facilities across the United States, the National Institute for Occupational Safety and Health conducted investigations during 2016-2017 to understand the burden of respiratory abnormalities, exposure characteristics, relationships between exposures and respiratory effects, and opportunities for exposure mitigation. Full-shift, task-based, and instantaneous personal and area air samples for diacetyl, 2,3-pentanedione and other VOCs were collected, and engineering controls were evaluated. Medical evaluations included questionnaire, spirometry, impulse oscillometry, and fractional exhaled nitric oxide. Exposure and health assessments were conducted using standardized tools and approaches, which enabled pooling data for aggregate analysis. The pooled data provided a larger population to better address the requestors' concern of the effect of exposure to alpha-diketones on the respiratory heath of coffee workers. This paper describes the rationale for the exposure and health assessment strategy, the approach used to achieve the study objectives, and its advantages and limitations.
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Affiliation(s)
| | | | - Jean M. Cox-Ganser
- Respiratory Health Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV, United States
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20
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Rozenberg D, McInnis M, Chow CW. Utilizing Automated Radiographic Signatures to Prognosticate Chronic Lung Allograft Dysfunction: What Does the Future Hold? Am J Respir Crit Care Med 2021; 204:883-885. [PMID: 34384039 PMCID: PMC8534617 DOI: 10.1164/rccm.202107-1726ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Dmitry Rozenberg
- University Health Network, 7989, Medicine, Respirology and Lung Transplantation , Toronto, Ontario, Canada;
| | - Micheal McInnis
- University Health Network, 7989, Joint Department of Medical Imaging, Toronto, Ontario, Canada
| | - Chung-Wai Chow
- University of Toronto, 7938, Medicine, Toronto, Ontario, Canada
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21
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Belloli EA, Gu T, Wang Y, Vummidi D, Lyu DM, Combs MP, Chughtai A, Murray S, Galbán CJ, Lama VN. Radiographic Graft Surveillance in Lung Transplantation: Prognostic Role of Parametric Response Mapping. Am J Respir Crit Care Med 2021; 204:967-976. [PMID: 34319850 DOI: 10.1164/rccm.202012-4528oc] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Chronic lung allograft dysfunction (CLAD) results in significant morbidity following lung transplantation. Potential CLAD occurs when lung function declines to 80-90% of baseline. Better non-invasive tools to prognosticate at potential CLAD are needed. OBJECTIVES To determine if parametric response mapping (PRM), a CT voxel-wise methodology, applied to high resolution CT scans can identify patients at risk of progression to CLAD or death. METHODS Radiographic features and PRM-based CT metrics quantifying functional small airways disease (PRMfSAD) and parenchymal disease (PRMPD) were studied at potential CLAD (n=61). High PRMfSAD and high PRMPD were defined as ≥ 30%. Restricted mean modeling was performed to compare CLAD-free survival among groups. MEASUREMENTS AND MAIN RESULTS PRM metrics identified 3 unique signatures: high PRMfSAD (11.5%), high PRMPD (41%) and neither (PRMNormal; 47.5%). Patients with high PRMfSAD or PRMPD had shorter CLAD-free median survival times (0.46 years and 0.50 years) compared to patients with predominantly PRMNormal (2.03 years; p=0.004 and 0.007 compared to PRMfSAD and PRMPD groups, respectively). In multivariate modeling adjusting for single versus double lung transplant, age at transplant, BMI at potential CLAD, and time from transplant to CT, PRMfSAD or PRMPD ≥ 30% continue to be statistically significant predictors of shorter CLAD-free survival. Air trapping by radiologist interpretation was common (66%), similar across PRM groups, and was not predictive of CLAD-free survival. Ground glass opacities by radiologist read occurred in 16% of cases and was associated with decreased CLAD-free survival (p<0.001). CONCLUSIONS PRM analysis offers valuable prognostic information at potential CLAD, identifying patients most at risk of developing CLAD or death.
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Affiliation(s)
- Elizabeth A Belloli
- University of Michigan, Pulmonary & Critical Care Medicine, Ann Arbor, Michigan, United States;
| | - Tian Gu
- University of Michigan, Biostatistics, Ann Arbor, Michigan, United States
| | - Yizhuo Wang
- University of Michigan School of Public Health, 51329, Biostatistics, Ann Arbor, Michigan, United States
| | - Dharshan Vummidi
- University of Michigan, Radiology, Ann Arbor, Michigan, United States
| | - Dennis M Lyu
- University of Michigan, Internal Medicine, Division Pulmonary & Critical Care, Ann Arbor, Michigan, United States
| | - Michael P Combs
- University of Michigan, Internal Medicine, Ann Arbor, Michigan, United States
| | - Aamer Chughtai
- University of Michigan, Radiology, Ann Arbor, Michigan, United States
| | - Susan Murray
- University of Michigan, School of Public Health, Biostatistics, Ann Arbor, Michigan, United States
| | - Craig J Galbán
- Center for Molecular Imaging, Michigan, Michigan, United States
| | - Vibha N Lama
- University of Michigan, 1259, Pulmonary and Critical Care Medicine, Ann Arbor, Michigan, United States
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22
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Renaud-Picard B, Koutsokera A, Cabanero M, Martinu T. Acute Rejection in the Modern Lung Transplant Era. Semin Respir Crit Care Med 2021; 42:411-427. [PMID: 34030203 DOI: 10.1055/s-0041-1729542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Acute cellular rejection (ACR) remains a common complication after lung transplantation. Mortality directly related to ACR is low and most patients respond to first-line immunosuppressive treatment. However, a subset of patients may develop refractory or recurrent ACR leading to an accelerated lung function decline and ultimately chronic lung allograft dysfunction. Infectious complications associated with the intensification of immunosuppression can also negatively impact long-term survival. In this review, we summarize the most recent evidence on the mechanisms, risk factors, diagnosis, treatment, and prognosis of ACR. We specifically focus on novel, promising biomarkers which are under investigation for their potential to improve the diagnostic performance of transbronchial biopsies. Finally, for each topic, we highlight current gaps in knowledge and areas for future research.
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Affiliation(s)
- Benjamin Renaud-Picard
- Division of Respirology and Toronto Lung Transplant Program, University of Toronto and University Health Network, Toronto, Canada
| | - Angela Koutsokera
- Division of Pulmonology, Lung Transplant Program, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Michael Cabanero
- Department of Pathology, Toronto General Hospital, University Health Network, Toronto, Canada
| | - Tereza Martinu
- Division of Respirology and Toronto Lung Transplant Program, University of Toronto and University Health Network, Toronto, Canada
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23
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Amubieya O, Ramsey A, DerHovanessian A, Fishbein GA, Lynch JP, Belperio JA, Weigt SS. Chronic Lung Allograft Dysfunction: Evolving Concepts and Therapies. Semin Respir Crit Care Med 2021; 42:392-410. [PMID: 34030202 DOI: 10.1055/s-0041-1729175] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The primary factor that limits long-term survival after lung transplantation is chronic lung allograft dysfunction (CLAD). CLAD also impairs quality of life and increases the costs of medical care. Our understanding of CLAD continues to evolve. Consensus definitions of CLAD and the major CLAD phenotypes were recently updated and clarified, but it remains to be seen whether the current definitions will lead to advances in management or impact care. Understanding the potential differences in pathogenesis for each CLAD phenotype may lead to novel therapeutic strategies, including precision medicine. Recognition of CLAD risk factors may lead to earlier interventions to mitigate risk, or to avoid risk factors all together, to prevent the development of CLAD. Unfortunately, currently available therapies for CLAD are usually not effective. However, novel therapeutics aimed at both prevention and treatment are currently under investigation. We provide an overview of the updates to CLAD-related terminology, clinical phenotypes and their diagnosis, natural history, pathogenesis, and potential strategies to treat and prevent CLAD.
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Affiliation(s)
- Olawale Amubieya
- Division of Pulmonary, Critical Care Medicine, Allergy, and Clinical Immunology, Department of Internal Medicine, The David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Allison Ramsey
- Division of Pulmonary, Critical Care Medicine, Allergy, and Clinical Immunology, Department of Internal Medicine, The David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Ariss DerHovanessian
- Division of Pulmonary, Critical Care Medicine, Allergy, and Clinical Immunology, Department of Internal Medicine, The David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Gregory A Fishbein
- Department of Pathology, The David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Joseph P Lynch
- Division of Pulmonary, Critical Care Medicine, Allergy, and Clinical Immunology, Department of Internal Medicine, The David Geffen School of Medicine at UCLA, Los Angeles, California
| | - John A Belperio
- Division of Pulmonary, Critical Care Medicine, Allergy, and Clinical Immunology, Department of Internal Medicine, The David Geffen School of Medicine at UCLA, Los Angeles, California
| | - S Samuel Weigt
- Division of Pulmonary, Critical Care Medicine, Allergy, and Clinical Immunology, Department of Internal Medicine, The David Geffen School of Medicine at UCLA, Los Angeles, California
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24
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Lundblad LKA, Robichaud A. Oscillometry of the respiratory system: a translational opportunity not to be missed. Am J Physiol Lung Cell Mol Physiol 2021; 320:L1038-L1056. [PMID: 33822645 PMCID: PMC8203417 DOI: 10.1152/ajplung.00222.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Airway oscillometry has become the de facto standard for quality assessment of lung physiology in laboratory animals and has demonstrated its usefulness in understanding diseases of small airways. Nowadays, it is seeing extensive use in daily clinical practice and research; however, a question that remains unanswered is how well physiological findings in animals and humans correlate? Methodological and device differences are obvious between animal and human studies. However, all devices deliver an oscillated airflow test signal and output respiratory impedance. In addition, despite analysis differences, there are ways to interpret animal and human oscillometry data to allow suitable comparisons. The potential with oscillometry is its ability to reveal universal features of the respiratory system across species, making translational extrapolation likely to be predictive. This means that oscillometry can thus help determine if an animal model displays the same physiological characteristics as the human disease. Perhaps more importantly, it can also be useful to determine whether an intervention is effective as well as to understand if it affects the desired region of the respiratory system, e.g., the periphery of the lung. Finally, findings in humans can also inform preclinical scientists and give indications as to what type of physiological changes should be observed in animal models to make them relevant as models of human disease. The present article will attempt to demonstrate the potential of oscillometry in respiratory research, an area where the development of novel therapies is plagued with a failure rate higher than in other disease areas.
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Affiliation(s)
- Lennart K A Lundblad
- Meakins-Christie Laboratories, McGill University, Montreal, Quebec, Canada.,THORASYS Thoracic Medical Systems Inc., Montreal, Quebec, Canada
| | - Annette Robichaud
- SCIREQ Scientific Respiratory Equipment Inc., Montreal, Quebec, Canada
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25
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Cottee AM, Seccombe LM, Thamrin C, Badal T, King GG, Peters MJ, Farah CS. Longitudinal monitoring of asthma in the clinic using respiratory oscillometry. Respirology 2021; 26:566-573. [PMID: 33797141 DOI: 10.1111/resp.14053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 02/23/2021] [Indexed: 01/18/2023]
Abstract
BACKGROUND AND OBJECTIVE Asthma guidelines emphasize the importance of assessing lung function and symptoms. The forced oscillation technique (FOT) and its longitudinal relationship with spirometry and symptoms are unresolved. We examined concordance between longitudinal spirometry, FOT and symptom control, and determined FOT limits of agreement in stable asthma. METHODS Over a 3-year period, adults with asthma attending a tertiary clinic completed the asthma control test (ACT), fraction of exhaled nitric oxide (FeNO), FOT and spirometry. Analysis included between-visit concordance for significant change using Cohen's kappa (κ) and stable asthma FOT limits of agreement. RESULTS Data (n = 186) from 855 visits (mean ± SD 4.6 ± 3.0 visits), 114 ± 95 days apart, were analysed. Between-visit concordance was moderate between reactance at 5 Hz (X5) and forced expiratory volume in 1 s (FEV1 ) (κ = 0.34, p = 0.001), and weak between ACT and FEV1 (κ = 0.18, p = 0.001). Change in FeNO did not correlate with lung function or ACT (κ < 0.05, p > 0.1). Stable asthma between visits (n = 75; 132 visits) had reduced lung function variability, but comparable concordance to the entire cohort. Limits of agreement for FEV1 (0.42 L), resistance at 5 Hz (2.06 cm H2 O s L-1 ) and X5 (2.75 cm H2 O s L-1 ) in stable asthma were at least twofold greater than published values in health. CONCLUSION In adults with asthma, there is moderate concordance between longitudinal change in FOT and spirometry. Both tests relate poorly to changes in asthma control, highlighting the need for multi-modal assessment in asthma rather than symptoms alone. The derivation of longitudinal FOT limits of agreement will assist in its clinical interpretation.
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Affiliation(s)
- Alice M Cottee
- Department of Respiratory Medicine, Concord Repatriation General Hospital, Concord, New South Wales, Australia.,Airway Physiology and Imaging Group and Woolcock Emphysema Centre, Woolcock Institute of Medical Research, Glebe, New South Wales, Australia.,Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Leigh M Seccombe
- Department of Respiratory Medicine, Concord Repatriation General Hospital, Concord, New South Wales, Australia.,Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Cindy Thamrin
- Airway Physiology and Imaging Group and Woolcock Emphysema Centre, Woolcock Institute of Medical Research, Glebe, New South Wales, Australia
| | - Tanya Badal
- Department of Respiratory Medicine, Concord Repatriation General Hospital, Concord, New South Wales, Australia.,Airway Physiology and Imaging Group and Woolcock Emphysema Centre, Woolcock Institute of Medical Research, Glebe, New South Wales, Australia.,Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
| | - Gregory G King
- Airway Physiology and Imaging Group and Woolcock Emphysema Centre, Woolcock Institute of Medical Research, Glebe, New South Wales, Australia.,Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.,Department of Respiratory Medicine, Royal North Shore Hospital, St Leonards, New South Wales, Australia
| | - Matthew J Peters
- Department of Respiratory Medicine, Concord Repatriation General Hospital, Concord, New South Wales, Australia.,Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.,Faculty of Medicine and Health Sciences, Macquarie University, North Ryde, New South Wales, Australia
| | - Claude S Farah
- Department of Respiratory Medicine, Concord Repatriation General Hospital, Concord, New South Wales, Australia.,Airway Physiology and Imaging Group and Woolcock Emphysema Centre, Woolcock Institute of Medical Research, Glebe, New South Wales, Australia.,Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.,Faculty of Medicine and Health Sciences, Macquarie University, North Ryde, New South Wales, Australia
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26
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Digital Health Technology and Telemedicine-Based Hospital and Home Programs in Pulmonary Medicine During the COVID-19 Pandemic. Am J Ther 2021; 28:e217-e223. [PMID: 33590991 DOI: 10.1097/mjt.0000000000001342] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND The current coronavirus disease 2019 (COVID-19) pandemic has caused a significant strain on medical resources throughout the world. A major shift to telemedicine and mobile health technologies has now taken on an immediate urgency. Newly developed devices designed for home use have facilitated remote monitoring of various physiologic parameters relevant to pulmonary diseases. These devices have also enabled home-based pulmonary rehabilitation programs. In addition, telemedicine and home care services have been leveraged to rapidly develop acute care hospital-at-home programs for the treatment of mild-to-moderate COVID-19 illness. AREAS OF UNCERTAINTY The benefit of remote monitoring technologies on patient outcomes has not been established in robust trials. Furthermore, the use of these devices, which can increase the burden of care, has not been integrated into current clinical workflows and electronic medical records. Finally, reimbursement for these telemedicine and remote monitoring services is variable. DATA SOURCES Literature review. THERAPEUTIC ADVANCES Advances in digital technology have improved remote monitoring of physiologic parameters relevant to pulmonary medicine. In addition, telemedicine services for the provision of pulmonary rehabilitation and novel hospital-at-home programs have been developed. These new home-based programs have been adapted for COVID-19 and may also be relevant for the management of acute and chronic pulmonary diseases after the pandemic. CONCLUSION Digital remote monitoring of physiologic parameters relevant to pulmonary medicine and novel hospital-at-home programs are feasible and may improve care for patients with acute and chronic respiratory-related disorders.
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27
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Hall AP, Tepper JS, Boyle MH, Cary MG, Flandre TG, Piaia A, Tarnow I, Macri NP, Freke MC, Nikula KJ, Paul GR, Cauvin A, Gregori M, Haworth R, Naylor S, Price M, Robinson IN, Allen A, Gelzleichter T, Hohlbaum AM, Manetz S, Wolfreys A, Colman K, Fleurance R, Jones D, Mukaratirwa S. BSTP Review of 12 Case Studies Discussing the Challenges, Pathology, Immunogenicity, and Mechanisms of Inhaled Biologics. Toxicol Pathol 2021; 49:235-260. [PMID: 33455525 DOI: 10.1177/0192623320976094] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The inhalation route is a relatively novel drug delivery route for biotherapeutics and, as a result, there is a paucity of published data and experience within the toxicology/pathology community. In recent years, findings arising in toxicology studies with inhaled biologics have provoked concern and regulatory challenges due, in part, to the lack of understanding of the expected pathology, mechanisms, and adversity induced by this mode of delivery. In this manuscript, the authors describe 12 case studies, comprising 18 toxicology studies, using a range of inhaled biotherapeutics (monoclonal antibodies, fragment antigen-binding antibodies, domain antibodies, therapeutic proteins/peptides, and an oligonucleotide) in rodents, nonhuman primates (NHPs), and the rabbit in subacute (1 week) to chronic (26 weeks) toxicology studies. Analysis of the data revealed that many of these molecules were associated with a characteristic pattern of toxicity with high levels of immunogenicity. Microscopic changes in the airways consisted of a predominantly lymphoid perivascular/peribronchiolar (PV/PB) mononuclear inflammatory cell (MIC) infiltrate, whereas changes in the terminal airways/alveoli were characterized by simple ("uncomplicated") increases in macrophages or inflammatory cell infiltrates ranging from mixed inflammatory cell infiltration to inflammation. The PV/PB MIC changes were considered most likely secondary to immunogenicity, whereas simple increases in alveolar macrophages were most likely secondary to clearance mechanisms. Alveolar inflammatory cell infiltrates and inflammation were likely induced by immune modulation or stimulation through pharmacologic effects on target biology or type III hypersensitivity (immune complex disease). Finally, a group of experts provide introductory thoughts regarding the adversity of inhaled biotherapeutics and the basis for reasonable differences of opinion that might arise between toxicologists, pathologists, and regulators.
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Affiliation(s)
| | | | | | | | - Thierry G Flandre
- 98560Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Alessandro Piaia
- 98560Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | | | | - Mark C Freke
- 70294Charles River Laboratories Montreal ULC, Senneville, Quebec, Canada
| | | | | | | | | | | | - Stuart Naylor
- Charles River Laboratories, Edinburgh, United Kingdom
| | - Mark Price
- 1929GlaxoSmithKline, Ware, United Kingdom
| | | | | | | | | | | | | | - Karyn Colman
- 70089Genomics Institute for the Novartis Research Foundation, San Diego, CA, USA
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28
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Kouri A, Gupta S, Yadollahi A, Ryan CM, Gershon AS, To T, Tarlo SM, Goldstein RS, Chapman KR, Chow CW. Addressing Reduced Laboratory-Based Pulmonary Function Testing During a Pandemic. Chest 2020; 158:2502-2510. [PMID: 32652095 PMCID: PMC7345485 DOI: 10.1016/j.chest.2020.06.065] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 06/23/2020] [Accepted: 06/27/2020] [Indexed: 01/04/2023] Open
Abstract
To reduce the spread of the severe acute respiratory syndrome coronavirus 2, many pulmonary function testing (PFT) laboratories have been closed or have significantly reduced their testing capacity. Because these mitigation strategies may be necessary for the next 6 to 18 months to prevent recurrent peaks in disease prevalence, fewer objective measurements of lung function will alter the diagnosis and care of patients with chronic respiratory diseases. PFT, which includes spirometry, lung volume, and diffusion capacity measurement, is essential to the diagnosis and management of patients with asthma, COPD, and other chronic lung conditions. Both traditional and innovative alternatives to conventional testing must now be explored. These may include peak expiratory flow devices, electronic portable spirometers, portable exhaled nitric oxide measurement, airwave oscillometry devices, and novel digital health tools such as smartphone microphone spirometers and mobile health technologies along with integration of machine learning approaches. The adoption of some novel approaches may not merely replace but could improve existing management strategies and alter common diagnostic paradigms. With these options comes important technical, privacy, ethical, financial, and medicolegal barriers that must be addressed. However, the coronavirus disease 19 pandemic also presents a unique opportunity to augment conventional testing by including innovative and emerging approaches to measuring lung function remotely in patients with respiratory disease. The benefits of such an approach have the potential to enhance respiratory care and empower patient self-management well beyond the current global pandemic.
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Affiliation(s)
- Andrew Kouri
- Division of Respirology, Department of Medicine, St. Michael's Hospital, Unity Health Toronto, Toronto, ON.
| | - Samir Gupta
- Division of Respirology, Department of Medicine, St. Michael's Hospital, Unity Health Toronto, Toronto, ON,Department of Medicine, University of Toronto, Toronto, ON
| | - Azadeh Yadollahi
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON,KITE-Toronto Rehabilitation Institute, University Health Network, Toronto, ON
| | - Clodagh M. Ryan
- Department of Medicine, University of Toronto, Toronto, ON,Division of Respirology, Department of Medicine, Toronto General Hospital, University Health Network, Toronto, ON
| | - Andrea S. Gershon
- Department of Medicine, University of Toronto, Toronto, ON,Division of Respirology, Department of Medicine, Sunnybrook Health Sciences Center, Toronto, ON
| | - Teresa To
- Child Health Evaluative Sciences, The Hospital for Sick Children, Toronto, ON,Dalla Lana Graduate School of Public Health, University of Toronto, Toronto, ON
| | - Susan M. Tarlo
- Department of Medicine, University of Toronto, Toronto, ON,Division of Respirology, Department of Medicine, Toronto Western Hospital, University Health Network, Toronto, ON
| | - Roger S. Goldstein
- Department of Medicine, University of Toronto, Toronto, ON,Division of Respiratory Medicine, West Part Healthcare Centre, Toronto, ON, Canada
| | - Kenneth R. Chapman
- Department of Medicine, University of Toronto, Toronto, ON,Division of Respirology, Department of Medicine, Toronto Western Hospital, University Health Network, Toronto, ON
| | - Chung-Wai Chow
- Department of Medicine, University of Toronto, Toronto, ON,Division of Respirology, Department of Medicine, Toronto General Hospital, University Health Network, Toronto, ON
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Porojan-Suppini N, Fira-Mladinescu O, Marc M, Tudorache E, Oancea C. Lung Function Assessment by Impulse Oscillometry in Adults. Ther Clin Risk Manag 2020; 16:1139-1150. [PMID: 33273817 PMCID: PMC7705955 DOI: 10.2147/tcrm.s275920] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 10/08/2020] [Indexed: 11/23/2022] Open
Abstract
Over the past decades, impulse oscillometry (IOS) has gained ground in the battery of pulmonary function tests. Performing the test requires minimal cooperation of the patient; therefore, it is a useful tool, especially in evaluating lung mechanics in children, elderly patients, and those who cannot perform spirometry. Oscillometry has also been used in both clinical and research departments. Studies were published mainly in asthma regarding detection of bronchodilator response and the therapeutic response to different drugs. Furthermore, it has been shown to be a sensitive technique to evaluate disease control. Other studied diseases were COPD, interstitial lung diseases, small airway disease, impairment of lung function due to exposure to occupational hazards or smoking, central airways obstruction, cystic fibrosis, monitoring lung mechanics during mechanical ventilation and sleep, neuromuscular diseases, lung transplant, and graft function. The aim of this review is to present the utility of oscillometry on the previously mentioned clinical fields.
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Affiliation(s)
- Noemi Porojan-Suppini
- Department of Pulmonology, Center for Research and Innovation in Personalized Medicine of Respiratory Diseases, University of Medicine and Pharmacy "Victor Babeș", Timișoara, Romania
| | - Ovidiu Fira-Mladinescu
- Department of Pulmonology, Center for Research and Innovation in Personalized Medicine of Respiratory Diseases, University of Medicine and Pharmacy "Victor Babeș", Timișoara, Romania
| | - Monica Marc
- Department of Pulmonology, Center for Research and Innovation in Personalized Medicine of Respiratory Diseases, University of Medicine and Pharmacy "Victor Babeș", Timișoara, Romania
| | - Emanuela Tudorache
- Department of Pulmonology, Center for Research and Innovation in Personalized Medicine of Respiratory Diseases, University of Medicine and Pharmacy "Victor Babeș", Timișoara, Romania
| | - Cristian Oancea
- Department of Pulmonology, Center for Research and Innovation in Personalized Medicine of Respiratory Diseases, University of Medicine and Pharmacy "Victor Babeș", Timișoara, Romania
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Lundblad LKA, Chow CW. Lung function monitoring in the era of respiratory pandemics. Clin Physiol Funct Imaging 2020; 40:377-379. [PMID: 32510779 PMCID: PMC7300824 DOI: 10.1111/cpf.12650] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/08/2020] [Accepted: 06/01/2020] [Indexed: 12/28/2022]
Affiliation(s)
- Lennart K A Lundblad
- Meakins-Christie Laboratories, McGill University & THORASYS Thoracic Medical Systems Inc., Montréal, QC, Canada
| | - Chung-Wai Chow
- Division of Respirology, Department of Medicine, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Toronto Lung Transplant Programme, Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
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31
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Usmani OS. Calling Time on Spirometry: Unlocking the Silent Zone in Acute Rejection after Lung Transplantation. Am J Respir Crit Care Med 2020; 201:1468-1470. [PMID: 32209030 PMCID: PMC7301740 DOI: 10.1164/rccm.202003-0581ed] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Omar S Usmani
- National Heart and Lung InstituteImperial College LondonLondon, United Kingdom
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