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Stewart GM, Fermoyle CC, Wheatley-Guy CM, Robach P, Tiller NB, Taylor BJ, Ziegler B, Schwartz J, Gavet A, Chabridon L, Murdock RW, Constantini K, Johnson BD. Effect of Ultramarathon Trail Running at Sea Level and Altitude on Alveolar-Capillary Function and Lung Diffusion. Med Sci Sports Exerc 2024; 56:1759-1769. [PMID: 38595212 DOI: 10.1249/mss.0000000000003448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
INTRODUCTION Endurance exercise at altitude can increase cardiac output and pulmonary vascular pressure to levels that may exceed the stress tolerability of the alveolar-capillary unit. This study examined the effect of ultramarathon trail racing at different altitudes (ranging from <1000 m to between 1500 and 2700 m) on alveolar-capillary recruitment and lung diffusion. METHODS Cardiac and lung function were examined before and after an ultramarathon in 67 runners (age: 41 ± 9 yr, body mass index: 23 ± 2 kg·m -2 , 10 females), and following 12-24 h of recovery in a subset ( n = 27). Cardiac biomarkers (cTnI and BNP) were assessed from whole blood, whereas lung fluid accumulation (comet tails), stroke volume (SV), and cardiac output ( Q ) were quantified via echocardiography. Lung diffusing capacity for carbon monoxide (DLco) and its components, alveolar membrane conductance (Dm) and capillary blood volume (Vc), were determined via a single-breath method at rest and during three stages of submaximal semirecumbent cycling (20, 30, and 40 W). RESULTS Average race time was 25 ± 12 h. From pre- to post-race, there was an increase in cardiac biomarkers (cTnI: 0.04 ± 0.02 vs 0.13 ± 0.03 ng·mL -1 , BNP: 20 ± 2 vs 112 ± 21 pg·mL -1 ; P < 0.01) and lung comet tails (2 ± 1 vs 7 ± 6, P < 0.01), a decrease in resting and exercise SV (76 ± 2 vs 69 ± 2 mL, 40 W: 93 ± 2 vs 88 ± 2 mL; P < 0.01), and an elevation in Q at rest (4.1 ± 0.1 vs 4.6 ± 0.2 L·min -1 , P < 0.01; 40 W: 7.3 ± 0.2 vs 7.4 ± 0.3 L·min -1 , P = 0.899). Resting DLco and Vc decreased after the race ( P < 0.01), whereas Dm was unchanged ( P = 0.465); however, during the three stages of exercise, DLco, Vc, and Dm were all reduced from pre- to post-race (40 W: 36.3 ± 0.9 vs 33.0 ± 0.8 mL·min -1 ·mm Hg -1 , 83 ± 3 vs 73 ± 2 mL, 186 ± 6 vs 170 ± 7 mL·min -1 ·mm Hg -1 , respectively; P < 0.01). When corrected for alveolar volume and Q , DLco decreased from pre- to post-race ( P < 0.01), and changes in DLco were similar for all ultramarathon events ( P > 0.05). CONCLUSIONS Competing in an ultramarathon leads to a transient increase in cardiac injury biomarkers, mild lung-fluid accumulation, and impairments in lung diffusion. Reductions in DLco are predominantly caused by a reduced Vc and possible pulmonary capillary de-recruitment at rest. However, impairments in alveolar-capillary recruitment and Dm both contribute to a fall in exertional DLco following an ultramarathon. Perturbations in lung diffusion were evident across a range of event distances and varying environmental exposures.
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Affiliation(s)
| | | | | | - Paul Robach
- Ecole Nationale des Sports de Montagne, Chamonix, FRANCE
| | - Nicholas B Tiller
- Institute of Respiratory Medicine and Exercise Physiology, Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrence, CA
| | - Bryan J Taylor
- Department of Cardiovascular Diseases, Mayo Clinic, Jacksonville, FL
| | - Briana Ziegler
- Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN
| | - Jesse Schwartz
- Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN
| | - Alice Gavet
- Ecole Nationale des Sports de Montagne, Chamonix, FRANCE
| | - Loïc Chabridon
- Ecole Nationale des Sports de Montagne, Chamonix, FRANCE
| | - Robert W Murdock
- Department of Cardiac Electrophysiology, Los Angeles Medical Center, Los Angeles, CA
| | - Keren Constantini
- School of public health, Sackler Faculty of Medicine, and Sylvan Adams Sports Institute, Tel-Aviv University, Tel Aviv, ISRAEL
| | - Bruce D Johnson
- Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN
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Satti I, Marshall JL, Harris SA, Wittenberg R, Tanner R, Lopez Ramon R, Wilkie M, Ramos Lopez F, Riste M, Wright D, Peralta Alvarez MP, Williams N, Morrison H, Stylianou E, Folegatti P, Jenkin D, Vermaak S, Rask L, Cabrera Puig I, Powell Doherty R, Lawrie A, Moss P, Hinks T, Bettinson H, McShane H. Safety of a controlled human infection model of tuberculosis with aerosolised, live-attenuated Mycobacterium bovis BCG versus intradermal BCG in BCG-naive adults in the UK: a dose-escalation, randomised, controlled, phase 1 trial. THE LANCET. INFECTIOUS DISEASES 2024; 24:909-921. [PMID: 38621405 DOI: 10.1016/s1473-3099(24)00143-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 02/16/2024] [Accepted: 02/20/2024] [Indexed: 04/17/2024]
Abstract
BACKGROUND Mycobacterium tuberculosis is the main causative agent of tuberculosis. BCG, the only licensed vaccine, provides inadequate protection against pulmonary tuberculosis. Controlled human infection models are useful tools for vaccine development. We aimed to determine a safe dose of aerosol-inhaled live-attenuated Mycobacterium bovis BCG as a surrogate for M tuberculosis infection, then compare the safety and tolerability of infection models established using aerosol-inhaled and intradermally administered BCG. METHODS This phase 1 controlled human infection trial was conducted at two clinical research facilities in the UK. Healthy, immunocompetent adults aged 18-50 years, who were both M tuberculosis-naive and BCG-naive and had no history of asthma or other respiratory diseases, were eligible for the trial. Participants were initially enrolled into group 1 (receiving the BCG Danish strain); the trial was subsequently paused because of a worldwide shortage of BCG Danish and, after protocol amendment, was restarted using the BCG Bulgaria strain (group 2). After a dose-escalation study, during which participants were sequentially allocated to receive either 1 × 103, 1 × 104, 1 × 105, 1 × 106, or 1 × 107 colony-forming units (CFU) of aerosol BCG, the maximum tolerated dose was selected for the randomised controlled trial. Participants in this trial were randomly assigned (9:12), by variable block randomisation and using sequentially numbered sealed envelopes, to receive aerosol BCG (1 × 107 CFU) and intradermal saline or intradermal BCG (1 × 106 CFU) and aerosol saline. Participants were masked to treatment allocation until day 14. The primary outcome was to compare the safety of a controlled human infection model based on aerosol-inhaled BCG versus one based on intradermally administered BCG, and the secondary outcome was to evaluate BCG recovery in the airways of participants who received aerosol BCG or skin biopsies of participants who received intradermal BCG. BCG was detected by culture and by PCR. The trial is registered at ClinicalTrials.gov, NCT02709278, and is complete. FINDINGS Participants were assessed for eligibility between April 7, 2016, and Sept 29, 2018. For group 1, 15 participants were screened, of whom 13 were enrolled and ten completed the study; for group 2, 60 were screened and 33 enrolled, all of whom completed the study. Doses up to 1 × 107 CFU aerosol-inhaled BCG were sufficiently well tolerated. No significant difference was observed in the frequency of adverse events between aerosol and intradermal groups (median percentage of solicited adverse events per participant, post-aerosol vs post-intradermal BCG: systemic 7% [IQR 2-11] vs 4% [1-13], p=0·62; respiratory 7% [1-19] vs 4% [1-9], p=0·56). More severe systemic adverse events occurred in the 2 weeks after aerosol BCG (15 [12%] of 122 reported systemic adverse events) than after intradermal BCG (one [1%] of 94; difference 11% [95% CI 5-17]; p=0·0013), but no difference was observed in the severity of respiratory adverse events (two [1%] of 144 vs zero [0%] of 97; 1% [-1 to 3]; p=0·52). All adverse events after aerosol BCG resolved spontaneously. One serious adverse event was reported-a participant in group 2 was admitted to hospital to receive analgesia for a pre-existing ovarian cyst, which was deemed unrelated to BCG infection. On day 14, BCG was cultured from bronchoalveolar lavage samples after aerosol infection and from skin biopsy samples after intradermal infection. INTERPRETATION This first-in-human aerosol BCG controlled human infection model was sufficiently well tolerated. Further work will evaluate the utility of this model in assessing vaccine efficacy and identifying potential correlates of protection. FUNDING Bill & Melinda Gates Foundation, Wellcome Trust, National Institute for Health Research Oxford Biomedical Research Centre, Thames Valley Clinical Research Network, and TBVAC2020.
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Affiliation(s)
- Iman Satti
- The Jenner Institute, University of Oxford, Oxford, UK
| | | | | | | | - Rachel Tanner
- The Jenner Institute, University of Oxford, Oxford, UK
| | | | - Morven Wilkie
- The Jenner Institute, University of Oxford, Oxford, UK
| | | | - Michael Riste
- The Jenner Institute, University of Oxford, Oxford, UK
| | - Daniel Wright
- The Jenner Institute, University of Oxford, Oxford, UK
| | | | - Nicola Williams
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | | | | | | | - Daniel Jenkin
- The Jenner Institute, University of Oxford, Oxford, UK
| | | | - Linnea Rask
- The Jenner Institute, University of Oxford, Oxford, UK
| | | | | | - Alison Lawrie
- The Jenner Institute, University of Oxford, Oxford, UK
| | - Paul Moss
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, UK
| | - Timothy Hinks
- Oxford Centre for Respiratory Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Henry Bettinson
- Oxford Centre for Respiratory Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Helen McShane
- The Jenner Institute, University of Oxford, Oxford, UK.
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Hua-Huy T, Pham-Ngoc H, Aubourg F, Lorut C, Roche N, Dinh-Xuan AT. Deciphering Alveolo-Capillary Gas Transfer Disturbances in Patients Recovering from COVID-19 Lung Disease. J Pers Med 2024; 14:738. [PMID: 39063992 PMCID: PMC11278216 DOI: 10.3390/jpm14070738] [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: 06/23/2024] [Revised: 07/04/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024] Open
Abstract
Impaired lung gas exchange is commonly seen in patients with pulmonary involvement related to SARS-CoV-2 acute infection or post-acute COVID-19 syndrome (PACS). The primary aim of our study was to assess lung gas transfer, measuring the pulmonary diffusion capacity for nitric oxide (DLNO) and carbon monoxide (DLCO) in all COVID-19 patients. Our secondary aim was to decipher the respective roles of perturbed lung membrane conductance (DM) and reduced pulmonary capillary volume (VC) in patients with impaired lung gas exchange. From May to October 2020, we measured DLNO-DLCO in 118 patients during their post-COVID-19 period (4.6 months after infection) to decipher alveolo-capillary gas transfer disturbances. DLNO-DLCO measurement was also performed in 28 healthy non-smokers as controls. Patients were classified into three groups according to the severity (mild, moderate, and severe) of acute COVID-19 infection. Patients with mild COVID-19 had normal lung volumes and airways expiratory flows but impaired pulmonary gas exchange, as shown by the significant decreases in DLNO, DLCO, DM, and VC as compared with controls. VC was significantly impaired and the DLNO/DLCO ratio was increased in patients with moderate (n = 4, 11%) and severe COVID-19 (n = 23, 49%). Abnormal membrane conductance was also seen in all three groups of post-COVID-19 patients. These findings suggest a persistent alveolo-capillary gas transfer defect, implying not only reduced membrane conductance but also abnormal pulmonary vascular capacitance in all PACS patients, even those with a milder form of COVID-19 infection.
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Affiliation(s)
- Thông Hua-Huy
- Lung Function & Respiratory Physiology Unit, Department of Respiratory Physiology and Sleep Medicine, Assistance Publique—Hôpitaux de Paris, Cochin Hospital, University Paris Cité, 75006 Paris, France
| | - Hà Pham-Ngoc
- Lung Function & Respiratory Physiology Unit, Department of Respiratory Physiology and Sleep Medicine, Assistance Publique—Hôpitaux de Paris, Cochin Hospital, University Paris Cité, 75006 Paris, France
| | - Frédérique Aubourg
- Lung Function & Respiratory Physiology Unit, Department of Respiratory Physiology and Sleep Medicine, Assistance Publique—Hôpitaux de Paris, Cochin Hospital, University Paris Cité, 75006 Paris, France
| | - Christine Lorut
- Department of Respiratory Medicine, APHP Centre, Institut Cochin (UMR 1016), Assistance Publique—Hôpitaux de Paris, Cochin Hospital, University Paris Cité, 75006 Paris, France
| | - Nicolas Roche
- Department of Respiratory Medicine, APHP Centre, Institut Cochin (UMR 1016), Assistance Publique—Hôpitaux de Paris, Cochin Hospital, University Paris Cité, 75006 Paris, France
| | - Anh Tuan Dinh-Xuan
- Lung Function & Respiratory Physiology Unit, Department of Respiratory Physiology and Sleep Medicine, Assistance Publique—Hôpitaux de Paris, Cochin Hospital, University Paris Cité, 75006 Paris, France
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Perez-Bogerd S, Van Muylem A, Zengin S, El Khloufi Y, Maufroy E, Faoro V, Malinovschi A, Michils A. LAMA improves tissue oxygenation more than LABA in patients with COPD. J Appl Physiol (1985) 2024; 137:154-165. [PMID: 38722752 DOI: 10.1152/japplphysiol.00467.2023] [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: 07/10/2023] [Revised: 04/11/2024] [Accepted: 05/01/2024] [Indexed: 07/13/2024] Open
Abstract
The effect of bronchodilators is mainly assessed with forced expiratory volume in 1 s (FEV1) in chronic obstructive pulmonary disease (COPD). Their impact on oxygenation and lung periphery is less known. Our objective was to compare the action of long-acting β2-agonists (LABA-olodaterol) and muscarinic antagonists (LAMA-tiotropium) on tissue oxygenation in COPD, considering their impact on proximal and peripheral ventilation as well as lung perfusion. FEV1, Helium slope (SHe) from a single-breath washout test (SHe decreases reflecting a peripheral ventilation improvement), frequency dependence of resistance (R5-R19), area under reactance (AX), lung capillary blood volume (Vc) from double diffusion (DLNO/DLCO), and transcutaneous oxygenation (TcO2) were measured before and 2 h post-LABA (day 1) and LAMA (day 3) in 30 patients with COPD (FEV1 54 ± 18% pred; GOLD A 31%/B 48%/E 21%) after 5-7 days of washout, respectively. We found that TcO2 increased more (P = 0.03) after LAMA (11 ± 12% from baseline, P < 001) compared with LABA (4 ± 11%, P = 0.06) despite a lower FEV1 increase (P = 0.03) and similar SHe (P = 0.98), AX (P = 0.63), and R5-R19 decreases (P = 0.37). TcO2 and SHe changes were negatively correlated (r = -0.47, P = 0.01) after LABA, not after LAMA (r = 0.10, P = 0.65). DLNO/DLCO decreased and Vc increased after LAMA (P = 0.04; P = 0.01, respectively) but not after LABA (P = 0.53; P = 0.24). In conclusion, LAMA significantly improved tissue oxygenation in patients with COPD, while only a trend was observed with LABA. The mechanisms involved may differ between both drugs: LABA increased peripheral ventilation, whereas LAMA increased lung capillary blood volume. Should oxygenation differences persist over time, LAMA could arguably become the first therapeutic choice in COPD.NEW & NOTEWORTHY Long-acting muscarinic antagonists (LAMAs) significantly improved tissue oxygenation in patients with COPD, while only a trend was observed with β2-agonists (LABAs). The mechanisms involved may differ between drugs: increased peripheral ventilation for LABA and likely lung capillary blood volume for LAMA. This could argue for LAMA as the first therapeutic choice in COPD.
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Affiliation(s)
- Silvia Perez-Bogerd
- Chest Department, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Alain Van Muylem
- Chest Department, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Selim Zengin
- Chest Department, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Yasmina El Khloufi
- Chest Department, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Emilie Maufroy
- Cardiopulmonary Exercise Laboratory, Faculty of Motorskill Science, Université Libre de Bruxelles, Brussels, Belgium
| | - Vitalie Faoro
- Cardiopulmonary Exercise Laboratory, Faculty of Motorskill Science, Université Libre de Bruxelles, Brussels, Belgium
| | - Andrei Malinovschi
- Department of Medical Sciences: Clinical Physiology, Uppsala University, Uppsala, Sweden
| | - Alain Michils
- Chest Department, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
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Loddé B, Giroux-Metges MA, Galinat H, Kerspern H, Pougnet R, Saliou P, Guerrero F, Lafère P. Does Decreased Diffusing Capacity of the Lungs for Carbon Monoxide Constitute a Risk of Decompression Sickness in Occupational Divers? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6516. [PMID: 37569056 PMCID: PMC10418885 DOI: 10.3390/ijerph20156516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 07/29/2023] [Accepted: 08/01/2023] [Indexed: 08/13/2023]
Abstract
Long-term alterations of pulmonary function (mainly decreased airway conductance and capacity of the lungs to diffuse carbon monoxide (DLCO)) have been described after hyperbaric exposures. However, whether these alterations convey a higher risk for divers' safety has never been investigated before. The purpose of the present pilot study was to assess whether decreased DLCO is associated with modifications of the physiological response to diving. In this case-control observational study, 15 "fit-to-dive" occupational divers were split into two groups according to their DLCO measurements compared to references values, either normal (control) or reduced (DLCO group). After a standardized 20 m/40 min dive in a sea water pool, the peak-flow, vascular gas emboli (VGE) grade, micro-circulatory reactivity, inflammatory biomarkers, thrombotic factors, and plasmatic aldosterone concentration were assessed at different times post-dive. Although VGE were recorded in all divers, no cases of decompression sickness (DCS) occurred. Compared to the control, the latency to VGE peak was increased in the DLCO group (60 vs. 30 min) along with a higher maximal VGE grade (p < 0.0001). P-selectin was higher in the DLCO group, both pre- and post-dive. The plasmatic aldosterone concentration was significantly decreased in the control group (-30.4 ± 24.6%) but not in the DLCO group. Apart from a state of hypocoagulability in all divers, other measured parameters remained unchanged. Our results suggest that divers with decreased DLCO might have a higher risk of DCS. Further studies are required to confirm these preliminary results.
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Affiliation(s)
- Brice Loddé
- ORPHY Laboratory, EA 4324, Western Brittany University (UBO), 29238 Brest, France
- Occupational Diseases Center, Brest University Hospital, 29609 Brest, France
| | - Marie-Agnès Giroux-Metges
- ORPHY Laboratory, EA 4324, Western Brittany University (UBO), 29238 Brest, France
- Respiratory Functional Exploration Unit, Brest University Hospital, 29609 Brest, France
| | - Hubert Galinat
- Department of Biological Hematology, Brest University Hospital, 29609 Brest, France
| | - Hèlène Kerspern
- Department of Biochemistry and Pharmaco-Toxicology, Brest University Hospital, 29609 Brest, France
| | - Richard Pougnet
- Occupational Diseases Center, Brest University Hospital, 29609 Brest, France
| | - Philippe Saliou
- ISERM, EFS, UMR 1078, GGB, Infection Control Unit, Western Brittany University (UBO), 29238 Brest, France
| | - François Guerrero
- ORPHY Laboratory, EA 4324, Western Brittany University (UBO), 29238 Brest, France
| | - Pierre Lafère
- ORPHY Laboratory, EA 4324, Western Brittany University (UBO), 29238 Brest, France
- Environmental, Occupational, Ageing (Integrative) Physiology Laboratory, HE2B, 1160 Brussels, Belgium
- DAN Europe Research Department, 1160 Brussels, Belgium
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Hughes M. The Roughton-Forster equation for pulmonary diffusion: how it happened. Eur Respir J 2022; 60:60/1/2200789. [PMID: 35902101 DOI: 10.1183/13993003.00789-2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 05/13/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Mike Hughes
- National Heart and Lung Institute, Imperial College School of Medicine, Hammersmith Hospital, London, UK
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Pulmonary function tests in systemic sclerosis-associated interstitial lung disease: new directions and future prospects. CURRENT OPINION IN PHYSIOLOGY 2021. [DOI: 10.1016/j.cophys.2021.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
This overview presents the recent progress in our understanding of gas transfer by the lungs during the respiratory cycle and during breath holding. Different phenomena intervene in gas transfer, convection and diffusion in the gas, dissolution, diffusion across the alveolar-capillary membrane, diffusion across blood plasma, and finally diffusion and reaction with hemoglobin inside blood cells. The different gases, O2 , CO, and NO, have very different reaction times with hemoglobin ranging from a few microseconds to tens of milliseconds. This is leading to different outcomes. For O2 , the solutions to the coupled nonlinear gas and blood equations are obtained at the acinus level. They include the fact that the acinar internal ventilation is strongly heterogeneous due to the arborescent structure. Also, in the dynamic calculation, one takes care of the delay between the start of inhalation and arrival of fresh air in the acinus. This "dead" time is the dynamic equivalent of the dead space ventilation. The question of the dependence of Vo2 on ventilation and perfusion takes a different form. The results show that Vo2 is not only a function of the ventilation/perfusion ratio but also depends on the variables: acinar ventilation VEac and perfusion Qac . The ratio VEac /Qac roughly determines arterial O2 saturation and arterial and alveolar O2 partial pressure. The classic Roughton-Forster interpretation of DLCO (separation between independent membrane and blood resistance) was a mathematical conjecture. It was shown recently that this conjecture was violated. This article presents an alternative interpretation that uses time concepts instead of resistance. © 2021 American Physiological Society. Compr Physiol 11:1289-1314, 2021.
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Affiliation(s)
- Bernard Sapoval
- Laboratoire de Physique de la Matière Condensée, CNRS, Ecole Polytechnique, Palaiseau, France
| | - Min-Yeong Kang
- Laboratoire de Physique de la Matière Condensée, CNRS, Ecole Polytechnique, Palaiseau, France
| | - Anh Tuan Dinh-Xuan
- Service de Physiologie-Explorations Fonctionnelles, Hôpital Cochin, AP-HP, Université Paris Descartes, Paris, France
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Abstract
Lung function testing has undisputed value in the comprehensive assessment and individualized management of chronic obstructive pulmonary disease, a pathologic condition in which a functional abnormality, poorly reversible expiratory airway obstruction, is at the core of its definition. After an overview of the physiologic underpinnings of the disease, the authors outline the role of lung function testing in this disease, including diagnosis, assessment of severity, and indication for and responses to pharmacologic and nonpharmacologic interventions. They discuss the current controversies surrounding test interpretation with these purposes in mind and provide balanced recommendations to optimize their usefulness in different clinical scenarios.
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Yamaguchi K, Tsuji T, Aoshiba K, Nakamura H, Abe S. Can DL NO/DL CO ratio offset prejudicial effects of functional heterogeneities in acinar regions? Respir Physiol Neurobiol 2020; 282:103517. [PMID: 32805419 DOI: 10.1016/j.resp.2020.103517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 08/03/2020] [Indexed: 02/07/2023]
Abstract
OBJECTIVES (1) To establish the general equation that describes relationship of DMCO/Vc versus DLNO/DLCO under conditions with no functional heterogeneities. (2) To examine the effects of functional heterogeneities, including parallel and series (stratified) heterogeneities, on DLNO/DLCO. RESULTS AND DISCUSSIONS (1) Given that "true" θNO in pulmonary capillaries is represented by surface absorption-related θNO, relationship between DMCO/Vc and DLNO/DLCO does not differ significantly from that obtained on premise of infinite θNO. DLNO/DLCO decided physiologically may mirror morphometric DMCO/Vc actually working for gas exchange but not "total" morphometric ratio of DMCO/Vc. (2) There are three parallel heterogeneities that affect diffusing capacity (D)-related parameters. Of them, only the heterogeneity of D/VA, where VA is alveolar volume, underestimates DLCO and DLNO. DLNO/DLCO does not alleviate negative impact of D/VA heterogeneity, indicating that DMCO/Vc estimated from DLNO/DLCO does not mirror "true" morphometric DMCO/Vc in diseased lungs with D/VA maldistribution. (3) Stratified heterogeneity underrates morphometric DMCO, DMNO, and DMNO/DMCO maximally by 1.4 %, 2.8 %, and 1.4 %, respectively, under conditions similar to single-breath D measurements, suggesting that effect of stratified heterogeneity on D measures is no longer needed to be considered in normal subjects but may be in patients having lung diseases with destructive lesions of acinar structures.
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Affiliation(s)
- Kazuhiro Yamaguchi
- Department of Respiratory Medicine, Tokyo Medical University, Tokyo 160-0023, Japan.
| | - Takao Tsuji
- Department of Respiratory Medicine, Tokyo Medical University, Tokyo 160-0023, Japan
| | - Kazutetsu Aoshiba
- Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, Ibaraki 300-0395, Japan
| | - Hiroyuki Nakamura
- Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, Ibaraki 300-0395, Japan
| | - Shinji Abe
- Department of Respiratory Medicine, Tokyo Medical University, Tokyo 160-0023, Japan
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Neder JA, Berton DC, Muller PT, O'Donnell DE. Incorporating Lung Diffusing Capacity for Carbon Monoxide in Clinical Decision Making in Chest Medicine. Clin Chest Med 2020; 40:285-305. [PMID: 31078210 DOI: 10.1016/j.ccm.2019.02.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lung diffusing capacity for carbon monoxide (Dlco) remains the only noninvasive pulmonary function test to provide an integrated picture of gas exchange efficiency in human lungs. Due to its critical dependence on the accessible "alveolar" volume (Va), there remains substantial misunderstanding on the interpretation of Dlco and the diffusion coefficient (Dlco/Va ratio, Kco). This article presents the physiologic and methodologic foundations of Dlco measurement. A clinically friendly approach for Dlco interpretation that takes those caveats into consideration is outlined. The clinical scenarios in which Dlco can effectively assist the chest physician are discussed and illustrative clinical cases are presented.
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Affiliation(s)
- J Alberto Neder
- Laboratory of Clinical Exercise Physiology, Division of Respirology and Sleep Medicine, Department of Medicine, Kingston Health Science Center, Queen's University, Richardson House, 102 Stuart Street, Kingston, Ontario K7L 2V6, Canada.
| | - Danilo C Berton
- Division of Respirology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Paulo T Muller
- Division of Respirology, Federal University of Mato Grosso do Sul, Campo Grande, Brazil
| | - Denis E O'Donnell
- Respiratory Investigation Unit, Division of Respirology and Sleep Medicine, Kingston Health Science Center & Queen's University, Kingston, Ontario, Canada
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Bergmann A, Jovanovska E, Schilling T, Hedenstierna G, Föllner S, Schreiber J, Hachenberg T. Early and late effects of remote ischemic preconditioning on spirometry and gas exchange in healthy volunteers. Respir Physiol Neurobiol 2020; 271:103287. [DOI: 10.1016/j.resp.2019.103287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 08/06/2019] [Accepted: 09/05/2019] [Indexed: 12/14/2022]
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D R Borland C, B Hughes JM. Lung Diffusing Capacities (D L ) for Nitric Oxide (NO) and Carbon Monoxide (CO): The Evolving Story. Compr Physiol 2019; 10:73-97. [PMID: 31853952 DOI: 10.1002/cphy.c190001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Nitric oxide and carbon monoxide diffusing capacities (DLNO and DLCO ) obey Fick's First Law of Diffusion and the basic principles of chemical kinetic theory. NO gas transfer is dominated by membrane diffusion (DM ), whereas CO transfer is limited by diffusion plus chemical reaction within the red cell. Marie Krogh, who pioneered the single-breath measurement of DLCO in 1915, believed that the combination of CO with red cell hemoglobin (Hb) was instantaneous. Roughton and colleagues subsequently showed, in vitro, that the reaction rate was finite, and prolonged in the presence of high P O 2 . Roughton and Forster (R-F) proposed that the resistance to transfer (1/DL ) was the sum of the membrane resistance (1/DM ) and (1/θVc), the red cell resistance (θ being the CO or NO conductance for blood uptake and Vc the capillary volume). From this R-F equation, DM for CO and Vc can be solved with simultaneous NO and CO inhalation. At near maximum exercise, DMCO and Vc for normal subjects were 88% and 79%, respectively, of morphometric values. The validity of these calculations depends on the values chosen for θ for CO and NO, and on the diffusivity of NO versus CO. Recent mathematical modeling suggests that θ for NO is "effectively" infinite because NO reacts only with Hb in the outer 0.1 μM of the red cell. An "infinite θNO " recalculation reduced DMCO to 53% and increased Vc to 95% of morphometric values. © 2020 American Physiological Society. Compr Physiol 10:73-97, 2020.
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Affiliation(s)
| | - J Mike B Hughes
- National Heart and Lung Institute, Imperial College, London, UK
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14
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Petousi N, Talbot NP, Pavord I, Robbins PA. Measuring lung function in airways diseases: current and emerging techniques. Thorax 2019; 74:797-805. [PMID: 31036773 DOI: 10.1136/thoraxjnl-2018-212441] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 02/14/2019] [Accepted: 02/25/2019] [Indexed: 12/12/2022]
Abstract
Chronic airways diseases, including asthma, COPD and cystic fibrosis, cause significant morbidity and mortality and are associated with high healthcare expenditure, in the UK and worldwide. For patients with these conditions, improvements in clinical outcomes are likely to depend on the application of precision medicine, that is, the matching of the right treatment to the right patient at the right time. In this context, the identification and targeting of 'treatable traits' is an important priority in airways disease, both to ensure the appropriate use of existing treatments and to facilitate the development of new disease-modifying therapy. This requires not only better understanding of airway pathophysiology but also an enhanced ability to make physiological measurements of disease activity and lung function and, if we are to impact on the natural history of these diseases, reliable measures in early disease. In this article, we outline some of the key challenges faced by the respiratory community in the management of airways diseases, including early diagnosis, disease stratification and monitoring of therapeutic response. In this context, we review the advantages and limitations of routine physiological measurements of respiratory function including spirometry, body plethysmography and diffusing capacity and discuss less widely used methods such as forced oscillometry, inert gas washout and the multiple inert gas elimination technique. Finally, we highlight emerging technologies including imaging methods such as quantitative CT and hyperpolarised gas MRI as well as quantification of lung inhomogeneity using precise in-airway gas analysis and mathematical modelling. These emerging techniques have the potential to enhance existing measures in the assessment of airways diseases, may be particularly valuable in early disease, and should facilitate the efforts to deliver precision respiratory medicine.
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Affiliation(s)
- Nayia Petousi
- Nuffield Department of Clinical Medicine Division of Experimental Medicine, University of Oxford, Oxford, UK .,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.,Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Nick P Talbot
- Nuffield Department of Clinical Medicine Division of Experimental Medicine, University of Oxford, Oxford, UK.,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.,Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Ian Pavord
- Nuffield Department of Clinical Medicine Division of Experimental Medicine, University of Oxford, Oxford, UK.,Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Trust, Oxford, UK
| | - Peter A Robbins
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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15
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Nassif M, van Steenwijk RP, van der Lee I, Sterk PJ, de Jongh FHC, Hogenhout JM, Tijssen JGP, Mulder BJM, de Winter RJ. Impact of atrial septal defect closure on diffusing capacity for nitric oxide and carbon monoxide. ERJ Open Res 2019; 5:00260-2018. [PMID: 30972347 PMCID: PMC6452032 DOI: 10.1183/23120541.00260-2018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Accepted: 02/19/2019] [Indexed: 11/05/2022] Open
Abstract
Atrial septal defects are characterised by a low D LNO /D LCOc ratio in diffusion testing. Successful percutaneous closure shows an increase in D LNO /D LCOc ratio and vital capacity through correction of a hyperdynamic pulmonary circulation. http://ow.ly/Rqkc30o5yMM.
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Affiliation(s)
- Martina Nassif
- Dept of Cardiology, Amsterdam UMC - University of Amsterdam, Amsterdam, The Netherlands
| | - Reindert P van Steenwijk
- Dept of Respiratory Medicine, Amsterdam UMC - University of Amsterdam, Amsterdam, The Netherlands
| | - Ivo van der Lee
- Dept of Pulmonology, Spaarne Hospital, Hoofddorp, The Netherlands
| | - Peter J Sterk
- Dept of Respiratory Medicine, Amsterdam UMC - University of Amsterdam, Amsterdam, The Netherlands
| | | | - Jacqueline M Hogenhout
- Dept of Respiratory Medicine, Amsterdam UMC - University of Amsterdam, Amsterdam, The Netherlands
| | - Jan G P Tijssen
- Dept of Cardiology, Amsterdam UMC - University of Amsterdam, Amsterdam, The Netherlands
| | - Barbara J M Mulder
- Dept of Cardiology, Amsterdam UMC - University of Amsterdam, Amsterdam, The Netherlands.,Netherlands Heart Institute, Utrecht, The Netherlands
| | - Robbert J de Winter
- Dept of Cardiology, Amsterdam UMC - University of Amsterdam, Amsterdam, The Netherlands
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16
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Neder JA, Marillier M, Bernard AC, O'Donnell DE. Transfer coefficient of the lung for carbon monoxide and the accessible alveolar volume: clinically useful if used wisely. Breathe (Sheff) 2019; 15:69-76. [PMID: 30838063 PMCID: PMC6395977 DOI: 10.1183/20734735.0345-2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A 67-year-old morbidly obese female (body mass index: 46.3 kg·m−2) with a history of long-term cigarette smoking (>30 pack-years) was referred from Cardiology to Respirology due to progressive dyspnoea and recent findings of extensive mosaic attenuation of the lungs on a high-resolution computed tomography (HRCT) scan (figure 1). She had been followed by Cardiology on the grounds of multivalvular disease (severe aortic stenosis and moderate mitral regurgitation), ischaemic heart disease, hypertension and hypercholesterolaemia. Transfer coefficient of the lung for carbon monoxide (KCO) and alveolar volume (VA) increase the yield of clinical information obtained from transfer factor of the lung for carbon monoxide (TLCO) measurements in clinical practicehttp://ow.ly/AVgu30na1vu
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Affiliation(s)
- J Alberto Neder
- Laboratory of Clinical Exercise Physiology and Respiratory Investigation Unit, Division of Respirology and Sleep Medicine, Dept of Medicine, Kingston Health Science Center and Queen's University, Kingston, ON, Canada
| | - Mathieu Marillier
- Laboratory of Clinical Exercise Physiology and Respiratory Investigation Unit, Division of Respirology and Sleep Medicine, Dept of Medicine, Kingston Health Science Center and Queen's University, Kingston, ON, Canada
| | - Anne-Catherine Bernard
- Laboratory of Clinical Exercise Physiology and Respiratory Investigation Unit, Division of Respirology and Sleep Medicine, Dept of Medicine, Kingston Health Science Center and Queen's University, Kingston, ON, Canada
| | - Denis E O'Donnell
- Laboratory of Clinical Exercise Physiology and Respiratory Investigation Unit, Division of Respirology and Sleep Medicine, Dept of Medicine, Kingston Health Science Center and Queen's University, Kingston, ON, Canada
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17
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Karrasch S, Radtke T, Simon M, Kronseder A, Dressel H, Jörres RA, Ochmann U. Acute effects of hypertonic saline inhalation on nitric oxide pulmonary diffusing capacity in healthy adults. Respir Physiol Neurobiol 2018; 258:40-46. [PMID: 30261306 DOI: 10.1016/j.resp.2018.09.007] [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: 08/06/2018] [Revised: 09/13/2018] [Accepted: 09/21/2018] [Indexed: 11/26/2022]
Abstract
We investigated acute effects of inhalation of hypertonic saline solution (HSS) and oxygen (O2, control exposure) on pulmonary diffusing capacity for nitric oxide (DLNO) and carbon monoxide (DLCO). In a randomized crossover study, 20 healthy, non-smoking subjects were allocated to short-term inhalation of HSS or O2. Spirometry [(forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC)] and combined single-breath DLNO-DLCO measurements were performed before and immediately after inhalation of either HSS or O2. Percent changes were presented as median values (interquartile range). After HSS inhalation, DLNO, FEV1 and FVC were decreased by -3.0% (-7.3, 0.5), -3.1% (-4.2, -1.6) and -1.2% (-3.3, 0.6), respectively (all P < 0.05), without significant effect on DLCO. No changes in spirometry and diffusing capacity were observed following O2 inhalation. Acute inhalation of HSS causes a slight decrease in membrane conductance, probably as a result of fluid imbalance at the alveolar surface and interstitial fluid accumulation, both of which could impair gas exchange.
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Affiliation(s)
- S Karrasch
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Ludwig-Maximilians-Universität, Munich, Germany; Institute of Epidemiology, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany; Comprehensive Pneumology Center Munich (CPC-M), Member of the German Center for Lung Research, Munich, Neuherberg, Germany
| | - T Radtke
- Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland; Division of Occupational and Environmental Medicine, University of Zurich and University Hospital Zurich, Zurich, Switzerland.
| | - M Simon
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Ludwig-Maximilians-Universität, Munich, Germany
| | - A Kronseder
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Ludwig-Maximilians-Universität, Munich, Germany
| | - H Dressel
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Ludwig-Maximilians-Universität, Munich, Germany; Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland; Division of Occupational and Environmental Medicine, University of Zurich and University Hospital Zurich, Zurich, Switzerland
| | - R A Jörres
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Ludwig-Maximilians-Universität, Munich, Germany; Comprehensive Pneumology Center Munich (CPC-M), Member of the German Center for Lung Research, Munich, Neuherberg, Germany
| | - U Ochmann
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Ludwig-Maximilians-Universität, Munich, Germany
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18
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Degano B, Soumagne T, Delaye T, Berger P, Perez T, Guillien A, Pellegrin JL, Launay D, Magy-Bertrand N, Agard C, Tiev KP, Hua-Huy T, Tardiff C, Diaz V, Chambellan A, Dinh-Xuan AT. Combined measurement of carbon monoxide and nitric oxide lung transfer does not improve the identification of pulmonary hypertension in systemic sclerosis. Eur Respir J 2017; 50:50/4/1701008. [DOI: 10.1183/13993003.01008-2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/20/2017] [Indexed: 12/11/2022]
Abstract
Screening is important to determine whether patients with systemic sclerosis (SSc) have pulmonary hypertension because earlier pulmonary hypertension treatment can improve survival in these patients. Although decreased transfer factor of the lung for carbon monoxide (TLCO) is currently considered the best pulmonary function test for screening for pulmonary hypertension in SSc, small series have suggested that partitioning TLCO into membrane conductance (diffusing capacity) for carbon monoxide (DMCO) and alveolar capillary blood volume (VC) through combined measurement of TLCO and transfer factor of the lung for nitric oxide (TLNO) is more effective to identify pulmonary hypertension in SSc patients compared with TLCO alone. Here, the objective was to determine whether combined TLCO–TLNO partitioned with recently refined equations could more accurately detect pulmonary hypertension than TLCO alone in SSc.For that purpose, 572 unselected consecutive SSc patients were retrospectively recruited in seven French centres.Pulmonary hypertension was diagnosed with right heart catheterisation in 58 patients. TLCO, TLNO and VC were all lower in SSc patients with pulmonary hypertension than in SSc patients without pulmonary hypertension. The area under the receiver operating characteristic curve for the presence of pulmonary hypertension was equivalent for TLCO (0.82, 95% CI 0.79–0.85) and TLNO (0.80, 95% CI 0.76–0.83), but lower for VC (0.75, 95% CI 0.71–0.78) and DMCO (0.66, 95% CI 0.62–0.70).Compared with TLCO alone, combined TLCO–TLNO does not add capability to detect pulmonary hypertension in unselected SSc patients.
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19
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Zavorsky GS. Nitric oxide uptake in the lung: It is about time that clinicians use this test routinely. Respir Physiol Neurobiol 2017; 241:1-2. [PMID: 28323204 DOI: 10.1016/j.resp.2017.03.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Gerald S Zavorsky
- Department of Respiratory Therapy, Georgia State University, Georgia State University Urban Life Building, Room 1229 (12th Floor), 140 Decatur Street SE, Atlanta, GA, 30302-4019, United States.
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