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Dridi R, Dridi N, Govindasamy K, Gmada N, Aouadi R, Guénard H, Laher I, Saeidi A, Suzuki K, Hackney AC, Zouhal H. Effects of Endurance Training Intensity on Pulmonary Diffusing Capacity at Rest and after Maximal Aerobic Exercise in Young Athletes. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182312359. [PMID: 34886081 PMCID: PMC8656668 DOI: 10.3390/ijerph182312359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/18/2021] [Accepted: 11/20/2021] [Indexed: 11/16/2022]
Abstract
This study compared the effects of varying aerobic training programs on pulmonary diffusing capacity (TLCO), pulmonary diffusing capacity for nitric oxide (TLNO), lung capillary blood volume (Vc) and alveolar-capillary membrane diffusing capacity (DM) of gases at rest and just after maximal exercise in young athletes. Sixteen healthy young runners (16-18 years) were randomly assigned to an intense endurance training program (IET, n = 8) or to a moderate endurance training program (MET, n = 8). The training volume was similar in IET and MET but with different work intensities, and each lasted for 8 weeks. Participants performed a maximal graded cycle bicycle ergometer test to measure maximal oxygen consumption (VO2max) and maximal aerobic power (MAP) before and after the training programs. Moreover, TLCO, TLNO and Vc were measured during a single breath maneuver. After eight weeks of training, all pulmonary parameters with the exception of alveolar volume (VA) and inspiratory volume (VI) (0.104 < p < 0889; 0.001 < ES < 0.091), measured at rest and at the end of maximal exercise, showed significant group × time interactions (p < 0.05, 0.2 < ES < 4.0). Post hoc analyses revealed significant pre-to-post decreases for maximal heart rates (p < 0.0001, ES = 3.1) and improvements for VO2max (p = 0.006, ES = 2.22) in the IET group. Moreover, post hoc analyses revealed significant pre-to-post improvements in the IET for DM, TLNO, TLCO and Vc (0.001 < p < 0.0022; 2.68 < ES < 6.45). In addition, there were increases in Vc at rest, VO2max, TLNO and DM in the IET but not in the MET participants after eight weeks of training with varying exercise intensities. Our findings suggest that the intensity of training may represent the most important factor in increasing pulmonary vascular function in young athletes.
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Affiliation(s)
- Rim Dridi
- Research Unit 17JS01 (Sport, Performance, Health and Society) Higher Institute of Sport and Physical Education of Ksar Said, University of La Manouba, Tunis 2010, Tunisia; (R.D.); (N.D.); (R.A.)
| | - Nadia Dridi
- Research Unit 17JS01 (Sport, Performance, Health and Society) Higher Institute of Sport and Physical Education of Ksar Said, University of La Manouba, Tunis 2010, Tunisia; (R.D.); (N.D.); (R.A.)
| | - Karuppasamy Govindasamy
- Department of Physical Education & Sports Science, SRM Institute of Science and Technology, Kattankulathur 603203, Tamilnadu, India;
| | - Nabil Gmada
- Physical Education and Sport Sciences Department, Sultan Qaboos University, Muscat 123, Oman;
| | - Ridha Aouadi
- Research Unit 17JS01 (Sport, Performance, Health and Society) Higher Institute of Sport and Physical Education of Ksar Said, University of La Manouba, Tunis 2010, Tunisia; (R.D.); (N.D.); (R.A.)
| | - Hervé Guénard
- Department of Physiology, Victor Segalen University, 33076 Bordeaux, France;
| | - Ismail Laher
- Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada;
| | - Ayoub Saeidi
- Department of Physical Education and Sport Sciences, University of Kurdistan, Pasdaran St., Sanandaj 6617715175, Iran;
| | - Katsuhiko Suzuki
- Faculty of Sport Sciences, Waseda University, Tokorozawa 359-1192, Japan
- Correspondence: (K.S.); (H.Z.)
| | - Anthony C. Hackney
- Department of Exercise & Sport Science, University of North Carolina, Chapel Hill, NC 27599, USA;
| | - Hassane Zouhal
- M2S (Laboratoire Mouvement, Sport, Santé)—EA 1274, Université de Rennes, 35000 Rennes, France
- Institut International des Sciences du Sport (2I2S), 35850 Irodouer, France
- Correspondence: (K.S.); (H.Z.)
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Zavorsky GS, Hsia CCW, Hughes JMB, Borland CDR, Guénard H, van der Lee I, Steenbruggen I, Naeije R, Cao J, Dinh-Xuan AT. Standardisation and application of the single-breath determination of nitric oxide uptake in the lung. Eur Respir J 2017; 49:49/2/1600962. [PMID: 28179436 DOI: 10.1183/13993003.00962-2016] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 10/26/2016] [Indexed: 01/03/2023]
Abstract
Diffusing capacity of the lung for nitric oxide (DLNO), otherwise known as the transfer factor, was first measured in 1983. This document standardises the technique and application of single-breath DLNO This panel agrees that 1) pulmonary function systems should allow for mixing and measurement of both nitric oxide (NO) and carbon monoxide (CO) gases directly from an inspiratory reservoir just before use, with expired concentrations measured from an alveolar "collection" or continuously sampled via rapid gas analysers; 2) breath-hold time should be 10 s with chemiluminescence NO analysers, or 4-6 s to accommodate the smaller detection range of the NO electrochemical cell; 3) inspired NO and oxygen concentrations should be 40-60 ppm and close to 21%, respectively; 4) the alveolar oxygen tension (PAO2 ) should be measured by sampling the expired gas; 5) a finite specific conductance in the blood for NO (θNO) should be assumed as 4.5 mL·min-1·mmHg-1·mL-1 of blood; 6) the equation for 1/θCO should be (0.0062·PAO2 +1.16)·(ideal haemoglobin/measured haemoglobin) based on breath-holding PAO2 and adjusted to an average haemoglobin concentration (male 14.6 g·dL-1, female 13.4 g·dL-1); 7) a membrane diffusing capacity ratio (DMNO/DMCO) should be 1.97, based on tissue diffusivity.
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Affiliation(s)
- Gerald S Zavorsky
- Dept of Respiratory Therapy, Georgia State University, Atlanta, GA, USA
| | - Connie C W Hsia
- Dept of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | - Colin D R Borland
- Dept of Medicine, University of Cambridge, Hinchingbrooke Hospital, Huntingdon, UK
| | - Hervé Guénard
- Dept of Physiology and Pulmonary Laboratory, University of Bordeaux and CHU, Bordeaux, France
| | - Ivo van der Lee
- Dept of Pulmonary Diseases, Spaarne Hospital, Hoofddorp, The Netherlands
| | | | - Robert Naeije
- Dept of Cardiology, Erasme University Hospital, Brussels, Belgium
| | - Jiguo Cao
- Dept of Statistics and Actuarial Science, Simon Fraser University, Burnaby, BC, Canada
| | - Anh Tuan Dinh-Xuan
- Dept of Physiology, Cochin Hospital, Paris Descartes University, Paris, France
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Davis C, Sheikh K, Pike D, Svenningsen S, McCormack DG, O'Donnell D, Neder JA, Parraga G. Ventilation Heterogeneity in Never-smokers and COPD:: Comparison of Pulmonary Functional Magnetic Resonance Imaging with the Poorly Communicating Fraction Derived From Plethysmography. Acad Radiol 2016; 23:398-405. [PMID: 26774739 DOI: 10.1016/j.acra.2015.10.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 09/22/2015] [Accepted: 10/04/2015] [Indexed: 11/29/2022]
Abstract
RATIONALE AND OBJECTIVES Pulmonary functional magnetic resonance imaging provides a way to quantify ventilation and its heterogeneity-a hallmark finding in chronic obstructive pulmonary disease (COPD). Unfortunately, the etiology and physiological meaning of ventilation defects and their relationship to pulmonary function and symptoms in COPD are not well understood. Another biomarker of ventilation heterogeneity is provided by the "poorly communicating fraction" (PCF), and is calculated as the ratio of total lung capacity to alveolar volume made using whole-body plethysmography. Our objective was to compare ventilation heterogeneity using hyperpolarized (3)He magnetic resonance imaging (MRI) and PCF measurements in elderly never-smokers and in ex-smokers with COPD. MATERIALS AND METHODS One hundred forty-six participants (71 ± 8 years, range = 48-87 years) provided written informed consent including 45 elderly never-smokers (71 ± 6 years, range = 61-84 years) and 101 ex-smokers with COPD (71 ± 8 years, range = 48-87 years). During a single 2-hour visit, spirometry, plethysmography, and hyperpolarized (3)He MRI were acquired. The MRI-derived ventilation defect percent (VDP) and plethysmography measurements were acquired and PCF values were calculated. Linear regression, Pearson correlations, and Bland-Altman analysis were used to evaluate the relationships for PCF and MRI VDP. RESULTS PCF (P < 0.001) and VDP (P < 0.001) were significantly increased with increasing COPD severity. There was a significant relationship for VDP and PCF (r = 0.68, P < 0.001) in all subjects and COPD subjects alone (r = 0.61, P < 0.001). Bland-Altman analysis showed that PCF and VDP were significantly different (mean bias = 9.7, upper limit = 32, lower limit = -13, P < 0.001), and in severe-grade COPD, PCF overestimates of VDP were significantly greater. CONCLUSIONS In elderly never-smokers and in ex-smokers with COPD, PCF and VDP are moderately correlated estimates of COPD ventilation heterogeneity that may be reflecting similar pathophysiology.
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Affiliation(s)
- Christopher Davis
- Imaging Research Laboratories, Robarts Research Institute, 1151 Richmond Street North, London, N6A 5B7, Canada
| | - Khadija Sheikh
- Imaging Research Laboratories, Robarts Research Institute, 1151 Richmond Street North, London, N6A 5B7, Canada; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, N6A 5B7, Canada
| | - Damien Pike
- Imaging Research Laboratories, Robarts Research Institute, 1151 Richmond Street North, London, N6A 5B7, Canada; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, N6A 5B7, Canada
| | - Sarah Svenningsen
- Imaging Research Laboratories, Robarts Research Institute, 1151 Richmond Street North, London, N6A 5B7, Canada; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, N6A 5B7, Canada
| | - David G McCormack
- Division of Respirology, Department of Medicine, The University of Western Ontario, London, Canada
| | - Denis O'Donnell
- Division of Respirology, Department of Medicine, Queens University, 99 University Ave, Kingston, K7L 3N6, Canada
| | - J Alberto Neder
- Division of Respirology, Department of Medicine, Queens University, 99 University Ave, Kingston, K7L 3N6, Canada
| | - Grace Parraga
- Imaging Research Laboratories, Robarts Research Institute, 1151 Richmond Street North, London, N6A 5B7, Canada; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond St North, London, N6A 5B7, Canada.
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Prediletto R, Fornai E, Catapano G, Carli C. Assessment of the alveolar volume when sampling exhaled gas at different expired volumes in the single breath diffusion test. BMC Pulm Med 2007; 7:18. [PMID: 18093300 PMCID: PMC2235885 DOI: 10.1186/1471-2466-7-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Accepted: 12/19/2007] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Alveolar volume measured according to the American Thoracic Society-European Respiratory Society (ATS-ERS) guidelines during the single breath diffusion test can be underestimated when there is maldistribution of ventilation. Therefore, the alveolar volume calculated by taking into account the ATS-ERS guidelines was compared to the alveolar volume measured from sequentiallly collected samples of the expired volume in two groups of individuals: COPD patients and healthy individuals. The aim of this study was to investigate the effects of the maldistribution of ventilation on the real estimate of alveolar volume and to evaluate some indicators suggestive of the presence of maldistribution of ventilation. METHODS Thirty healthy individuals and fifty patients with moderate-severe COPD were studied. The alveolar volume was measured either according to the ATS-ERS guidelines or considering the whole expired volume subdivided into five quintiles. An index reflecting the non-uniformity of the distribution of ventilation was then derived (DeltaVA/VE). RESULTS Significant differences were found when comparing the two measurements and the alveolar volume by quintiles appeared to have increased progressively towards residual volume in healthy individuals and much more in COPD patients. Therefore, DeltaVA/VE resulted in an abnormal increase in COPD. CONCLUSION The results of our study suggest that the alveolar volume during the single breath diffusion test should be measured through the collection of a sample of expired volume which could be more representative of the overall gas composition, especially in the presence of uneven distribution of ventilation. Further studies aimed at clarifying the final effects of this way of calculating the alveolar volume on the measure of DLCO are needed. DeltaVA/VE is an index that can help assess the severity of inhomogeneity in COPD patients.
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Affiliation(s)
- Renato Prediletto
- Institute of Clinical Physiology, National Research Council of Italy, Pisa, Italy
| | - Edo Fornai
- Institute of Clinical Physiology, National Research Council of Italy, Pisa, Italy
| | - Giosuè Catapano
- Institute of Clinical Physiology, National Research Council of Italy, Pisa, Italy
| | - Cristina Carli
- Institute of Clinical Physiology, National Research Council of Italy, Pisa, Italy
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Horstman MJM, Mertens FW, Schotborg D, Hoogsteden HC, Stam H. Comparison of Total-Breath and Single-Breath Diffusing Capacity in Healthy Volunteers and COPD Patients. Chest 2007; 131:237-44. [PMID: 17218582 DOI: 10.1378/chest.06-1115] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND The measurement of single-breath diffusing capacity (Dlco(SB)) assumes that diffusing capacity per liter of alveolar volume (Dlco/VA) determined in a 750-mL gas sample represents the diffusing capacity (Dlco) of the entire lung. Fast-responding gas analyzers provide the opportunity to verify this assumption because of the possibility to measure CO and CH(4) fractions continuously throughout the entire expiration. Continuous gas sampling provides more information per measurement, but this information cannot be expressed in the traditional parameters. Our goals were to find new parameters to express the extra information of the continuous gas sampling, and to compare these new parameters with the traditional parameters. METHODS We compared a new method to determine Dlco with the traditional method in 62 healthy volunteers and 26 COPD patients. Traditionally, Dlco(SB) is determined by multiplying Dlco/VA with alveolar volume, both calculated from gas concentrations in a 750-mL gas sample. The new method calculates total-breath Dlco (Dlco(TB)) by integration of Dlco/VA against exhaled volume. RESULTS In healthy volunteers, Dlco/VA shows a slight upward slope during exhalation, while in COPD patients Dlco/VA shows a horizontal line. Total-breath total lung capacity (TLC) is larger than single-breath TLC both in healthy volunteers and in COPD patients, leading to a Dlco(TB) that is significantly larger than Dlco(SB) in both groups (p < 0.001). CONCLUSION The assumption that a 750-mL gas sample represents the entire lung seems to be correct for Dlco/VA but not for the CH(4) fraction in case of ventilation inhomogeneity.
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Affiliation(s)
- Maartje J M Horstman
- Department of Pulmonary Diseases, Erasmus University, V203, PO Box 2040, 3000 CA Rotterdam, the Netherlands.
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Glénet SN, de Bisschop CMM, Dridi R, Guénard HJP. Membrane conductance in trained and untrained subjects using either steady state or single breath measurements of NO transfer. Nitric Oxide 2006; 15:199-208. [PMID: 16793294 DOI: 10.1016/j.niox.2006.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2005] [Revised: 02/13/2006] [Accepted: 04/12/2006] [Indexed: 11/30/2022]
Abstract
The aim of this work was to define the relationship between membrane conductance for NO (Dm) and physical activity by using either the steady state NO transfer (T(LNO)SS) or the single breath method (T(LNO)SB), making the hypothesis that NO transfer is only limited by the membrane. Alterations in T(LNO)SS with lung volume during tidal ventilation were measured in six subjects at rest and during steady exercise at 30, 60, and 80% of maximal aerobic power (MAP). A fast responding chemoluminescent NO analyser was used. Two calculation methods were used by sampling NO: (1) at mid-tidal volume, (2) in the middle of the alveolar plateau. T(LNO)SB at rest and maximal oxygen consumption (V(.-)O(2)max) were also measured in 18 other subjects. At rest T(LNO)SS with method 2 was 192% of the value given by method 1. T(LNO)SS with method 1 increased by 50% with 80% MAP as it did not change with method 2. Method 2 seemed inaccurate. T(LNO)SB at rest, which is closely related to Dm, was correlated to age and V(.-)O(2)max, T(LNO)SB=182-1.2 age+24.3 V(.-)O(2) max(l min(-1)) (p<0.01, r(2)=0.72). The T(LNO)SS and T(LNO)SB versus lung volume relationships suggest an influence of the breathing pattern on Dm. Dm can be estimated either by these two NO transfer methods, however the use of the T(LNO)SS method is highly sensitive to the alveolar sampling level. Dm increase during exercise is a function of MAP. Dm at rest decreases with age as it increases with MAP.
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Affiliation(s)
- Stéphane N Glénet
- Laboratoire des Adaptations Physiologiques aux Activités Physiques, Faculté des Sciences du Sport Poitiers, UPRES-EA 3813, France.
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Huang YCT, O'brien SR, Vredenburgh J, Folz RJ, Macintyre NR. Intrabreath analysis of carbon monoxide uptake during exercise in patients at risk for lung injury. Respir Med 2006; 100:1226-33. [PMID: 16314083 DOI: 10.1016/j.rmed.2005.10.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2005] [Revised: 10/07/2005] [Accepted: 10/20/2005] [Indexed: 11/25/2022]
Abstract
The single exhalation analysis of carbon monoxide, acetylene, and methane allows the determination of intrabreath (regional) DL, pulmonary capillary blood flow and ventilation inhomogeneities during rest and exercise. We reasoned that this technique might be more sensitive in detecting regional pulmonary capillary abnormalities than resting single breath DL (DL(sb)). We selected a group of breast cancer patients in high-dose chemotherapy (HDCT) protocols who were at risk for pulmonary injury. We grouped the patients into pre-HDCT and post-HDCT, and used resting DL(sb) to further categorize the latter into those with and without pulmonary injury. We found that exercise DL increases were blunted in post-HDCT patients with low resting DL(sb). More importantly, even in post-HDCT patients with normal resting DL(sb), exercise DL response was reduced in the slowest emptying lung units along with evidence for ventilation inhomogeneities (increased methane slope). We conclude that exercise assessments of DL at low lung volumes and gas mixing properties may be sensitive indicators of lung injury.
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Affiliation(s)
- Yuh-Chin T Huang
- Human Studies Division, National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
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Harris RS, Hadian M, Hess DR, Chang Y, Venegas JG. Pulmonary Artery Occlusion Increases the Ratio of Diffusing Capacity for Nitric Oxide to Carbon Monoxide in Prone Sheep. Chest 2004; 126:559-65. [PMID: 15302745 DOI: 10.1378/chest.126.2.559] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
OBJECTIVE To test the hypothesis that the ratio of diffusing capacity of the lung for nitric oxide (DLno) to diffusing capacity of the lung for carbon monoxide (DLco) would be affected by occlusion of a fraction of the pulmonary vascular bed. DESIGN Interventional physiologic study. SETTING Animal laboratory of a university hospital. SUBJECTS Thirteen sheep. INTERVENTIONS We simultaneously measured single-breath DLno and DLco in anesthetized and mechanically ventilated sheep (fraction of inspired oxygen [Fio(2)] of 1.0) before and after pulmonary artery occlusion by inflation of a balloon (n = 6), and by autologous clot embolism (n = 4). To see if the effect also occurred on Fio(2) of 0.21, four animals were studied during ventilation with room air, one of which was also in the Fio(2) of 1.0 group (14 total experiments with 13 sheep). RESULTS On Fio(2) of 1.0, the mean DLno/Dlco ratio rose by 35% from 4.76 +/- 0.41 in control to 6.42 +/- 0.82 after balloon occlusion (p = 0.002), and by 54% from 7.55 +/- 2.09 to 11.6 +/- 2.61 (p = 0.005) after autologous clot embolism (+/- SD). An equivalent relative increase of 27% took place during ventilation with room air, but the DLno/DLco ratio was lower (3.14 +/- 0.22 in control and 3.98 +/- 0.38 after balloon occlusion). Independent of the method of obstruction or Fio(2), the increase in DLno/DLco ratio was mostly due to a drop in DLco. The DLno/Dlco ratio reduced much of the intersubject variability of either DLno or DLco alone. CONCLUSION The DLno/DLco ratio increased after pulmonary artery occlusion regardless of the method of occlusion or Fio(2). This increase may be a result of a greater sensitivity of DLco than DLno to a regional reduction in capillary blood flow.
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Affiliation(s)
- R Scott Harris
- Pulmonary and Critical Care Unit, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USAL.
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9
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Abstract
Nitric oxide (NO) was first detected in the exhaled breath more than a decade ago and has since been investigated as a noninvasive means of assessing lung inflammation. Exhaled NO arises from the airway and alveolar compartments, and new analytical methods have been developed to characterize these sources. A simple two-compartment model can adequately represent many of the observed experimental observations of exhaled concentration, including the marked dependence on exhalation flow rate. The model characterizes NO exchange by using three flow-independent exchange parameters. Two of the parameters describe the airway compartment (airway NO diffusing capacity and either the maximum airway wall NO flux or the airway wall NO concentration), and the third parameter describes the alveolar region (steady-state alveolar NO concentration). A potential advantage of the two-compartment model is the ability to partition exhaled NO into an airway and alveolar source and thus improve the specificity of detecting altered NO exchange dynamics that differentially impact these regions of the lungs. Several analytical techniques have been developed to estimate the flow-independent parameters in both health and disease. Future studies will focus on improving our fundamental understanding of NO exchange dynamics, the analytical techniques used to characterize NO exchange dynamics, as well as the physiological interpretation and the clinical relevance of the flow-independent parameters.
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Affiliation(s)
- Steven C George
- Department of Chemical Engineering and Materials Science, University of California, Irvine 92697-2575, USA.
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Zavorsky GS, Quiron KB, Massarelli PS, Lands LC. The Relationship Between Single-Breath Diffusion Capacity of the Lung for Nitric Oxide and Carbon Monoxide During Various Exercise Intensities. Chest 2004; 125:1019-27. [PMID: 15006963 DOI: 10.1378/chest.125.3.1019] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVES To determine the relationship between single-breath diffusion capacity of the lung for nitric oxide (DLNO) and single-breath diffusion capacity of the lung for carbon monoxide (DLCO), and to determine the single-breath DLNO/DLCO ratios during rest and at several exercise intensities using a commercial lung diffusion system that uses electrochemical cells to analyze gases. SETTING AND PARTICIPANTS Eight healthy men (age, 27 +/- 5 years; weight, 83.0 +/- 11.8 kg; height, 180.4 +/- 9.5 cm; maximal oxygen uptake [VO(2)max], 47.6 +/- 10.2 mL/kg/min [mean +/- SD]) performed single-breath DLNO measurements (inspired nitric oxide concentration, 66.5 +/- 10.6 ppm) and carbon monoxide (0.30%) randomized on different days at rest and at various exercise intensities (40%, 75%, and 90% of VO(2)max reserve [VO(2)R]) on a electrically braked load simulator. The DLCO measured on day 1 was compared to the DLCO measured during the DLNO method from another day. RESULTS The relationship between DLNO and DLCO was linear (DLNO = 4.47 x DLCO; r(2) = 0.91; standard error of the estimate = 0.04; p < 0.05). DLNO was 4.52 +/- 0.24 times greater than DLCO, independent of exercise intensity. DLNO increased from 210.3 +/- 18.2 mL/min/mm Hg at rest to 284.2 +/- 38.6 mL/min/mm Hg at 90% VO(2)R (oxygen uptake = 42.6 +/- 9.8 mL/kg/min; 284.2 +/- 31.6 W; p < 0.05). Stepwise regression demonstrated that DLNO is predicted by alveolar volume (VA) [in liters] and workload (watts) such that DLNO = 13.4 x VA + 0.23 x workload + 107.7 (r(2) = 0.90; SEE = 17.5; p < 0.05). CONCLUSION (1) Single-breath DLNO and DLCO increase linearly with increasing workload; (2) the single-breath DLNO/DLCO ratios are independent of exercise intensity, suggesting that using either nitric oxide or carbon monoxide as transfer gases are valid in the study of lung diffusion during any level of exercise; and (3) DLNO is mainly predicted by VA and workload.
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Affiliation(s)
- Gerald S Zavorsky
- Department of Exercise Science, Concordia University, Montreal, QC, Canada.
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Kondo R, Haniuda M, Yamanda T, Sato E, Fujimoto K, Kubo K, Amano J. Effects of expiratory pressure on nitric oxide in exhaled breath. Is exhaled nitric oxide really unaffected by pressure? Respir Physiol Neurobiol 2004; 139:33-40. [PMID: 14637308 DOI: 10.1016/j.resp.2003.09.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The measurements of exhaled nitric oxide (ENO) concentrations in several previous reports have been quite disparate but the cause of this variability is unclear. In the present study, we have attempted to elucidate the effects of expiratory pressure upon ENO values by taking measurements at pressures ranging from 2 to 10 cmH2O in control subjects and in both smokers and asthmatics. Differences in ENO concentrations (delta pNO) were then estimated and the concentration levels were found to increase with elevated expiratory pressure levels in both the control volunteers and in the asthmatics (under 2 and 3 L/min flow rates). These results indicate that changes in expiratory pressure indeed affect ENO concentrations. The measurement of ENO concentrations in human patients must therefore be undertaken using standard procedures that must incorporate expiratory pressure levels in order to properly interpret ENO values.
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Affiliation(s)
- Ryoichi Kondo
- Department of Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
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Shin HW, Rose-Gottron CM, Cooper DM, Hill M, George SC. Impact of high-intensity exercise on nitric oxide exchange in healthy adults. Med Sci Sports Exerc 2003; 35:995-1003. [PMID: 12783048 DOI: 10.1249/01.mss.0000072247.46963.cd] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE After exercise, exhaled NO concentration has been reported to decrease, remain unchanged, or increase. A more mechanistic understanding of NO exchange dynamics after exercise is needed to understand the relationship between exercise and NO exchange. METHODS We measured several flow-independent NO exchange parameters characteristic of airway and alveolar regions using a single breath maneuver and a two-compartment model (maximum flux of NO from the airways, J'(awNO), pL x s-1; diffusing capacity of NO in the airways, D(awNO), pL x s-1 x ppb-1; steady state alveolar concentration, C(alv,ss), ppb; mean airway tissue NO concentration, C(awNO), ppb), as well as serum IL-6 at baseline, 3, 30, and 120 min after a high-intensity exercise challenge in 10 healthy adults (21-37 yr old). RESULTS D(awNO) (mean +/- SD) increased (37.1 +/- 44.4%), whereas J'(awNO) and C(awNO) decreased (-7.27 +/- 11.1%, -26.1 +/- 24.6%, respectively) 3 min postexercise. IL-6 increased steadily after exercise to 481% +/- 562% above baseline 120 min postexercise. CONCLUSION High-intensity exercise acutely enhances the ability of NO to diffuse between the airway tissue and the gas phase, and exhaled NO might be used to probe both the metabolic and physical properties of the airways.
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Affiliation(s)
- Hye-Won Shin
- Department of Chemical Engineering and Materials Science, University of California, Irvine, 92697, USA
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Huang YCT, O'Brien SR, MacIntyre NR. Intrabreath diffusing capacity of the lung in healthy individuals at rest and during exercise. Chest 2002; 122:177-85. [PMID: 12114355 DOI: 10.1378/chest.122.1.177] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Traditional approaches to measuring the diffusing capacity of the lung for carbon monoxide (DLCO) treat the lung as a single, well-mixed compartment and produce a single value for DLCO to represent an average diffusing capacity of the lung (DL). Because DL distribution in the lung is inhomogeneous, and changes in the DL in diseased lungs may be regional, measuring regional DL, especially during exercise, may be more sensitive in detecting pulmonary vascular diseases. OBJECTIVES To characterize regional changes in DL in healthy individuals from rest to exercise, and to provide normal references for future studies in pulmonary vascular disorders. METHODS We reanalyzed DLCO and phase III CH(4) slopes that were obtained during a slow, single exhalation at rest and during exercise in our extended database of 105 healthy individuals. DLCO profiles between 20% and 80% of exhaled vital capacity (VC) (ie, the intrabreath DLCO) were analyzed by calculating the average DLCO measured at midlung volume (ie, 30 to 45% of exhaled VC [DLCOMLV]) and by fitting the whole curve with a third-order polynomial equation. RESULTS DLCO decreased nonlinearly by approximately 30%, from 20 to 80% of exhaled VC at rest. DLCO during exercise was greater than that at rest, and the increase was similar at all lung volumes. The CH(4) slopes at rest and during exercise were similar. Prediction equations based on regressions on age, sex, and height were computed for resting and exercise DLCOMLV and the phase III CH(4) slope (an index of ventilation distribution). CONCLUSIONS Capillary recruitment/dilation during exercise in healthy individuals is a uniform process throughout the lungs. Our analyses provide a database for a noninvasive method that can incorporate exercise to evaluate the volume-dependent distribution of DLCO in lung diseases.
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Affiliation(s)
- Yuh-Chin T Huang
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.
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14
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Perillo IB, Hyde RW, Olszowka AJ, Pietropaoli AP, Frasier LM, Torres A, Perkins PT, Forster RE, Utell MJ, Frampton MW. Chemiluminescent measurements of nitric oxide pulmonary diffusing capacity and alveolar production in humans. J Appl Physiol (1985) 2001; 91:1931-40. [PMID: 11641327 DOI: 10.1152/jappl.2001.91.5.1931] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Measurements of nitric oxide (NO) pulmonary diffusing capacity (DL(NO)) multiplied by alveolar NO partial pressure (PA(NO)) provide values for alveolar NO production (VA(NO)). We evaluated applying a rapidly responding chemiluminescent NO analyzer to measure DL(NO) during a single, constant exhalation (Dex(NO)) or by rebreathing (Drb(NO)). With the use of an initial inspiration of 5-10 parts/million of NO with a correction for the measured NO back pressure, Dex(NO) in nine healthy subjects equaled 125 +/- 29 (SD) ml x min(-1) x mmHg(-1) and Drb(NO) equaled 122 +/- 26 ml x min(-1) x mmHg(-1). These values were 4.7 +/- 0.6 and 4.6 +/- 0.6 times greater, respectively, than the subject's single-breath carbon monoxide diffusing capacity (Dsb(CO)). Coefficients of variation were similar to previously reported breath-holding, single-breath measurements of Dsb(CO). PA(NO) measured in seven of the subjects equaled 1.8 +/- 0.7 mmHg x 10(-6) and resulted in VA(NO) of 0.21 +/- 0.06 microl/min using Dex(NO) and 0.20 +/- 0.6 microl/min with Drb(NO). Dex(NO) remained constant at end-expiratory oxygen tensions varied from 42 to 682 Torr. Decreases in lung volume resulted in falls of Dex(NO) and Drb(NO) similar to the reported effect of volume changes on Dsb(CO). These data show that rapidly responding chemiluminescent NO analyzers provide reproducible measurements of DL(NO) using single exhalations or rebreathing suitable for measuring VA(NO).
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Affiliation(s)
- I B Perillo
- Department of Medicine, School of Medicine and Dentistry, University of Rochester, NY 14627, USA.
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Tsoukias NM, Dabdub D, Wilson AF, George SC. Effect of alveolar volume and sequential filling on the diffusing capacity of the lungs: II. Experiment. RESPIRATION PHYSIOLOGY 2000; 120:251-71. [PMID: 10828341 DOI: 10.1016/s0034-5687(00)00104-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The diffusing capacity of the lung, DL, is a critical physiological parameter, yet the currently accepted clinical model (Jones-Meade) assumes a well-mixed alveolar region, and a constant DL independent of alveolar volume, VA, despite experimental evidence to the contrary. We have formulated a new mathematical model [Tsoukias, N.M, Wilson, A.F., George, S.C., 2000. Respir. Physiol. 120, 231-249] that considers variable alveolar mixing through a single parameter, k (0<k<1), and a DL that is a positive function of VA (DL=a+bVA or DL=alphaVA(beta)). The goal of this study is to determine the suitability of this model to determine the unknown parameters a, b, alpha, beta, and k from experimental data in normal subjects. The model predicts that the normal lung fills, in part, sequentially (k=0.51+/-0.35). The following average values in all seven subjects were obtained: DLNO=48.VA(2/3) ml/min/mmHg and DLCO=20+0.7.VA ml/min/mmHg (STPD) where VA is expressed in L (STPD). We conclude that the mathematical model is suitable for identifying the unknown parameters and thus can be used to characterize the degree of alveolar mixing (or sequential filling) as well as the volume dependence of DL.
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Affiliation(s)
- N M Tsoukias
- Department of Chemical and Biochemical Engineering and Materials Science, 916 Engineering Tower, University of California, 92697-2575, Irvine, CA, USA
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