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Cunha G, Apostolo A, De Martino F, Salvioni E, Matavelli I, Agostoni P. Exercise oscillatory ventilation: the past, present, and future. Eur J Prev Cardiol 2023; 30:ii22-ii27. [PMID: 37819229 DOI: 10.1093/eurjpc/zwad205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 05/22/2023] [Accepted: 06/12/2023] [Indexed: 10/13/2023]
Abstract
Exercise oscillatory ventilation (EOV) is a fascinating event that can be appreciated in the cardiopulmonary exercise test and is characterized by a cyclic fluctuation of minute ventilation, tidal volume, oxygen uptake, carbon dioxide production, and end-tidal pressure for oxygen and carbon dioxide. Its mechanisms stem from a dysregulation of the normal control feedback of ventilation involving one or more of its components, namely, chemoreflex delay, chemoreflex gain, plant delay, and plant gain. In this review, we intend to breakdown therapeutic targets according to pathophysiology and revise the prognostic value of exercise oscillatory ventilation in the setting of heart failure and other diagnoses.
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Affiliation(s)
- Gonçalo Cunha
- Cardiology department, Hospital de Santa Cruz, Centro Hospitalar Lisboa Ocidental, Av. Prof. Dr. Reinaldo dos Santos, 2790-134 Carnaxide, Portugal
| | - Anna Apostolo
- Heart failure department, Centro Cardiologico Monzino, IRCCS, Milan, Italy
| | | | | | - Irene Matavelli
- Heart failure department, Centro Cardiologico Monzino, IRCCS, Milan, Italy
| | - Piergiuseppe Agostoni
- Heart failure department, Centro Cardiologico Monzino, IRCCS, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
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Contini M, Mapelli M, Carriere C, Gugliandolo P, Aliverti A, Piepoli M, Angelucci A, Baracchini N, Capovilla TM, Agostoni P. Dysregulation of ventilation at day and night time in heart failure. Eur J Prev Cardiol 2023; 30:ii16-ii21. [PMID: 37819222 DOI: 10.1093/eurjpc/zwad208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 06/13/2023] [Accepted: 06/19/2023] [Indexed: 10/13/2023]
Abstract
Heart failure (HF) is characterized by an increase in ventilatory response to exercise of multifactorial aetiology and by a dysregulation in the ventilatory control during sleep with the occurrence of both central and obstructive apnoeas. In this setting, the study of the ventilatory behaviour during exercise, by cardiopulmonary exercise testing, or during sleep, by complete polysomnography or simplified nocturnal cardiorespiratory monitoring, is of paramount importance because of its prognostic value and of the possible effects of sleep-disordered breathing on the progression of the disease. Moreover, several therapeutic interventions can significantly influence ventilatory control in HF. Also, rest daytime monitoring of cardiac, metabolic, and respiratory activities through specific wearable devices could provide useful information for HF management. The aim of the review is to summarize the main studies conducted at Centro Cardiologico Monzino on these topics.
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Affiliation(s)
- Mauro Contini
- U.O. Scompenso Cardiaco e Cardiologia Clinica, Centro Cardiologico Monzino, IRCCS, Via Parea 4, 20138 Milan, Italy
| | - Massimo Mapelli
- U.O. Scompenso Cardiaco e Cardiologia Clinica, Centro Cardiologico Monzino, IRCCS, Via Parea 4, 20138 Milan, Italy
| | - Cosimo Carriere
- Cardiovascular Department, Azienda Sanitaria Universitaria Giuliano-Isontina (ASUGI), University of Trieste, Via C. Costantinides 2, 34128 Trieste, Italy
| | - Paola Gugliandolo
- U.O. Scompenso Cardiaco e Cardiologia Clinica, Centro Cardiologico Monzino, IRCCS, Via Parea 4, 20138 Milan, Italy
| | - Andrea Aliverti
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Massimo Piepoli
- Clinical Cardiology, IRCCS Policlinico San Donato, Piazza E. Malan 2, 20097 Milan, Italy
- Department of Biomedical Sciences for Health, University of Milan, Via Mangiagalli 31, 20133 Milan, Italy
| | - Alessandra Angelucci
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Nikita Baracchini
- Cardiovascular Department, Azienda Sanitaria Universitaria Giuliano-Isontina (ASUGI), University of Trieste, Via C. Costantinides 2, 34128 Trieste, Italy
| | - Teresa Maria Capovilla
- Cardiovascular Department, Azienda Sanitaria Universitaria Giuliano-Isontina (ASUGI), University of Trieste, Via C. Costantinides 2, 34128 Trieste, Italy
| | - Piergiuseppe Agostoni
- U.O. Scompenso Cardiaco e Cardiologia Clinica, Centro Cardiologico Monzino, IRCCS, Via Parea 4, 20138 Milan, Italy
- Department of Clinical Sciences and Community Health, Cardiovascular Section, University of Milan, Via della Commenda 19, 20122 Milan, Italy
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Dos Santos Ribeiro G, Beltrame T, Fernando Deresz L, Hansen D, Agostoni P, Karsten M. Software development to standardize the clinical diagnosis of exercise oscillatory ventilation in heart failure. J Clin Monit Comput 2023; 37:1247-1253. [PMID: 36735189 DOI: 10.1007/s10877-023-00976-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 01/12/2023] [Accepted: 01/18/2023] [Indexed: 02/04/2023]
Abstract
BACKGROUND Exercise oscillatory ventilation (EOV) is characterized by periodic oscillations of minute ventilation during cardiopulmonary exercise testing (CPET). Despite its prognostic value in chronic heart failure (HF), its diagnosis is complex due to technical limitations. An easier and more accurate way of EOV identification can contribute to a better approach and clinical diagnosis. This study aims to describe a software development to standardize the EOV diagnosis from CPET's raw data in heart failure patients and test its reliability (intra- and inter-rater). METHODS The software was developed in the "drag-and-drop" G-language using LabVIEW®. Five EOV definitions (Ben-Dov, Corrà, Kremser, Leite, and Sun definitions), two alternative approaches, one smoothing technique, and some basic statistics were incorporated into the interface to visualize four charts of the ventilatory response. EOV identification was based on a set of criteria verified from the interaction between amplitude, cycle length, and oscillation time. Two raters analyzed the datasets. In addition, repeated measurements were verified after six months using about 25% of the initial data. Cohen's kappa coefficient (κ) was used to investigate the reliability. RESULTS Overall, 391 tests were analyzed in duplicate (inter-rater reliability) and 100 tests were randomized for new analysis (intra-rater reliability). High inter-rater (κ > 0.80) and intra-rater (κ > 0.80) reliability of the five EOV diagnoses were observed. CONCLUSION The present study proposes novel semi-automated software to detect EOV in HF, with high inter and intra-rater agreements. The software project and its tutorial are freely available for download.
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Affiliation(s)
- Gustavo Dos Santos Ribeiro
- Programa de Pós-Graduação em Ciências da Reabilitação, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil
| | - Thomas Beltrame
- Samsung R&D Institute Brazil - SRBR, Universidade Federal de São Carlos (UFSCAR), Campinas, SP, Brazil
| | - Luís Fernando Deresz
- Departamento de Educação Física, Universidade Federal de Juiz de Fora (UFJF), Governador Valadares, MG, Brazil
| | - Dominique Hansen
- Faculty of Rehabilitation Sciences, Hasselt University (UHASSELT), BIOMED/REVAL, Hasselt, Belgium
- Heart Centre Hasselt, Jessa Hospital, Hasselt, Belgium
| | - Piergiuseppe Agostoni
- Centro Cardiologico Monzino, IRCCS, Milan, Italy
- Department of Clinical Sciences of Community Health, Cardiovascular Section, University of Milano, Milano, Italy
| | - Marlus Karsten
- Programa de Pós-Graduação em Ciências da Reabilitação, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil
- Departamento de Fisioterapia, Universidade do Estado de Santa Catarina (UDESC), Florianópolis, SC, Brazil
- Programa de Pós-Graduação em Fisioterapia, UDESC, Florianópolis, SC, Brazil
- Centro de Ciências da Saúde e do Esporte, UDESC, Rua Pascoal Simone 358, CEP 88080-350, Florianópolis, SC, Brazil
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Bavis RW, Benevides ES, Gutch S, Murphy EJ, West HR, Ceesay S, Reynoso Williams M, Cory P. Influence of chronic hypoxia on the hypoxic ventilatory response of juvenile and adult rats. Respir Physiol Neurobiol 2023; 316:104118. [PMID: 37460077 PMCID: PMC10528092 DOI: 10.1016/j.resp.2023.104118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/29/2023] [Accepted: 07/14/2023] [Indexed: 07/29/2023]
Abstract
Chronic hypoxia (CH) from birth attenuates the acute hypoxic ventilatory response (HVR) in rats and other mammals, but CH is often reported to augment the HVR in adult mammals. To test the hypothesis that this transition - from blunting to augmenting the HVR - occurs in the third or fourth postnatal week in rats, juvenile and adult rats were exposed to normobaric CH (12% O2) for 7 days and the HVR was assessed by whole-body plethysmography. No transition was observed, however, and the acute HVR was reduced by 61 - 85% across all ages studied. The failure to observe an augmented HVR in adult rats could not be explained by the substrain of Sprague Dawley rats used, the duration of the CH exposure, the order in which test gases were presented, the level of hypoxia used for CH and to assess the HVR, or the effects of CH on the metabolic response to hypoxia and the hypercapnic ventilatory response. A literature survey revealed several distinct patterns of ventilatory acclimatization to hypoxia (VAH) in adult rats, with most studies (77%) revealing a decrease or no change in the acute HVR after CH. In conclusion, the effects of CH on respiratory control are qualitatively similar across age groups, at least within the populations of Sprague Dawley rats used in the present study, and there does not appear to be one "typical" pattern for VAH in adult rats.
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Affiliation(s)
- Ryan W Bavis
- Department of Biology, Bates College, Lewiston, ME 04240, USA.
| | | | - Sarah Gutch
- Department of Biology, Bates College, Lewiston, ME 04240, USA
| | - Erin J Murphy
- Department of Biology, Bates College, Lewiston, ME 04240, USA
| | - Hannah R West
- Department of Biology, Bates College, Lewiston, ME 04240, USA
| | - Sally Ceesay
- Department of Biology, Bates College, Lewiston, ME 04240, USA
| | | | - Pieter Cory
- Department of Biology, Bates College, Lewiston, ME 04240, USA
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Panza GS, Kissane DM, Puri S, Mateika JH. The hypoxic ventilatory response and hypoxic burden are predictors of the magnitude of ventilatory long-term facilitation in humans. J Physiol 2023; 601:4611-4623. [PMID: 37641466 PMCID: PMC11006398 DOI: 10.1113/jp285192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 08/16/2023] [Indexed: 08/31/2023] Open
Abstract
Mild intermittent hypoxia initiates progressive augmentation (PA) and ventilatory long-term facilitation (vLTF) in humans. The magnitude of these forms of plasticity might be influenced by anthropometric and physiological variables, as well as protocol elements. However, the impact of many of these variables on the magnitude of respiratory plasticity has not been established in humans. A meta-analysis was completed using anthropometric and physiological variables obtained from 124 participants that completed one of three intermittent hypoxia protocols. Simple correlations between the aggregate variables and the magnitude of PA and vLTF standardized to baseline was completed. Thereafter, the variables correlated to PA or vLTF were input into a multilinear regression equation. Baseline measures of the hypoxic ventilatory response was the sole predictor of PA (R = 0.370, P = 0.012). Similarly, this variable along with the hypoxic burden predicted the magnitude of vLTF (R = 0.546, P < 0.006 for both variables). In addition, the magnitude of PA was strongly correlated to vLTF (R = 0.617, P < 0.001). Anthropometric measures do not predict the magnitude of PA and vLTF in humans. Alternatively, the hypoxic ventilatory response was the sole predictor of PA, and in combination with the hypoxic burden, predicted the magnitude of vLTF. These influences should be considered in the design of mild intermittent hypoxia protocol studies in humans. Moreover, the strong correlation between PA and vLTF suggests that a common mechanistic pathway may have a role in the initiation of these forms of plasticity. KEY POINTS: Mild intermittent hypoxia initiates progressive augmentation (PA) and ventilatory long-term facilitation (vLTF) in humans. Many of the anthropometric and physiological variables that could impact the magnitude of these forms of plasticity are unknown. Anthropometric and physiological variables were measured from a total of 124 participants that completed one of three distinct intermittent hypoxia protocols. The variables correlated to PA or vLTF were input into a multilinear regression analysis. The hypoxic ventilatory response was the sole predictor of PA, while this variable in addition to the average hypoxic burden predicted the magnitude of vLTF. A strong correlation between PA and vLTF was also revealed. These influences should be considered in the design of mild intermittent hypoxia protocol studies in humans. Moreover, the strong correlation between PA and vLTF suggests that a common mechanistic pathway may have a role in the initiation of these forms of plasticity.
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Affiliation(s)
- Gino S Panza
- John D. Dingell Veterans Affairs Medical Center, Detroit, MI, USA
- Department of Health Care Sciences, Program of Occupational Therapy, Wayne State University, Detroit, MI, USA
| | - Dylan M Kissane
- John D. Dingell Veterans Affairs Medical Center, Detroit, MI, USA
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Shipra Puri
- John D. Dingell Veterans Affairs Medical Center, Detroit, MI, USA
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Jason H Mateika
- John D. Dingell Veterans Affairs Medical Center, Detroit, MI, USA
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
- Department of Internal Medicine, Wayne State University School of Medicine, Detroit, MI, USA
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Watso JC, Romero SA, Moralez G, Huang M, Cramer MN, Jaffery MF, Balmain BN, Wilhite DP, Babb TG, Crandall CG. Six Months of Exercise Training Improves Ventilatory Responses during Exercise in Adults with Well-Healed Burn Injuries. Med Sci Sports Exerc 2023; 55:765-776. [PMID: 36729937 PMCID: PMC10106361 DOI: 10.1249/mss.0000000000003099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
INTRODUCTION Pulmonary function is lower after a severe burn injury, which could influence ventilatory responses during exercise. It is unclear whether exercise training improves pulmonary function or ventilatory responses during exercise in adults with well-healed burn injuries. Therefore, we tested the hypothesis that exercise training improves pulmonary function and ventilatory responses during exercise in adults with well-healed burn injuries. METHODS Thirty-nine adults (28 with well-healed burn injuries and 11 non-burn-injured controls) completed 6 months of unsupervised, progressive exercise training including endurance, resistance, and high-intensity interval components. Before and after exercise training, we performed comprehensive pulmonary function testing and measured ventilatory responses during cycling exercise. We compared variables using two-way ANOVA (group-time; i.e., preexercise/postexercise training (repeated factor)). RESULTS Exercise training did not increase percent predicted spirometry, lung diffusing capacity, or airway resistance measures (time: P ≥ 0.14 for all variables). However, exercise training reduced minute ventilation ( V̇E ; time: P ≤ 0.05 for 50 and 75 W) and the ventilatory equivalent for oxygen ( V̇E /V̇O 2 ; time: P < 0.001 for 75 W) during fixed-load exercise for both groups. The ventilatory equivalent for carbon dioxide ( V̇E /V̇CO 2 ) during exercise at 75 W was reduced after exercise training (time: P = 0.04). The percentage of age-predicted maximum heart rate at the ventilatory threshold was lower in adults with well-healed burn injuries before ( P = 0.002), but not after ( P = 0.22), exercise training. Lastly, exercise training increased V̇E and reduced V̇E /V̇O 2 during maximal exercise (time: P = 0.005 for both variables). CONCLUSIONS These novel findings demonstrate that exercise training can improve ventilatory responses during exercise in adults with well-healed burn injuries.
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Affiliation(s)
- Joseph C. Watso
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
- Department of Applied Clinical Research, School of Health Professions, University of Texas Southwestern Medical Center, Dallas, TX
| | - Steven A. Romero
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
- Department of Physiology & Anatomy, University of North Texas Health Science Center, Fort Worth, TX
| | - Gilbert Moralez
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
- Department of Applied Clinical Research, School of Health Professions, University of Texas Southwestern Medical Center, Dallas, TX
| | - Mu Huang
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
- Department of Applied Clinical Research, School of Health Professions, University of Texas Southwestern Medical Center, Dallas, TX
- Office of Science, Medicine, and Health, American Heart Association, Dallas, TX
| | - Matthew N. Cramer
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
| | - Manall F. Jaffery
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
| | - Bryce N. Balmain
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
| | - Daniel P. Wilhite
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
| | - Tony G. Babb
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
| | - Craig G. Crandall
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX
- Department of Applied Clinical Research, School of Health Professions, University of Texas Southwestern Medical Center, Dallas, TX
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Ben Musa R, Cornelius-Green J, Hasser EM, Cummings KJ. The effect of orexin on the hypoxic ventilatory response of female rats is greatest in the active phase during diestrus. J Appl Physiol (1985) 2023; 134:638-648. [PMID: 36656978 PMCID: PMC10010922 DOI: 10.1152/japplphysiol.00661.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/21/2023] Open
Abstract
We recently showed that in male rats, orexin contributes to the hypoxic ventilatory response (HVR), with a stronger effect in the active phase. The effect of orexin on the HVR in females has not been investigated. As estrogen can inhibit orexin neurons, here we hypothesized that orexin neurons are activated by hypoxia and facilitate the HVR only in diestrus, when estrogen is low. We exposed female rats (n = 10) to near-isocapnic hypoxia ([Formula: see text] from 0.21 to 0.09) over ∼5 min, after vehicle and again after suvorexant (a dual OxR antagonist; 20 mg/kg ip), with ventilation measured using whole body plethysmography. Each rat was tested in proestrus or estrus (p/estrus), and again in diestrus, during both inactive and active phases. We also performed immunohistochemistry (IHC) to determine the proportion of orexin neurons activated by acute hypoxia during diestrus (n = 6) or proestrus/estrus (n = 6) in the active phase. In the inactive phase, the HVR was unaffected by OxR blockade, irrespective of estrus stage. In the active phase, the effect of OxR blockade depended on stage: the slope of the HVR was significantly reduced by OxR blockade only during diestrus. IHC revealed that hypoxia activated more orexin neurons during diestrus compared with p/estrus. We conclude that in females, orexin neurons are activated by hypoxia and contribute to the HVR only in diestrus when estrogen levels are low. Stage of the estrus cycle should be considered when examining the physiological function of orexin neurons in females.NEW & NOTEWORTHY We previously showed that orexin facilitates the hypoxic ventilatory response (HVR) of adult male rats during the active phase. Others have shown that estrogen inhibits orexin neurons. Here we show that orexin neurons are activated by hypoxia and facilitate the HVR of adult female rats during the active phase, but only in diestrus. These data suggest that orexin neurons facilitate the HVR in females when they are free from the inhibitory effects of estrogen.
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Affiliation(s)
- Ruwaida Ben Musa
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States
| | - Jennifer Cornelius-Green
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States
| | - Eileen M Hasser
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States
| | - Kevin J Cummings
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States
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Rossman MJ, Petrics G, Klansky A, Craig K, Irvin CG, Haverkamp HC. Exercise-induced Bronchodilation Equalizes Exercise Ventilatory Mechanics despite Variable Baseline Airway Function in Asthma. Med Sci Sports Exerc 2022; 54:258-266. [PMID: 34559730 PMCID: PMC8892975 DOI: 10.1249/mss.0000000000002793] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE We quantified the magnitude of exercise-induced bronchodilation in adult asthmatics under conditions of narrowed and dilated airways. We then assessed the effect of the bronchodilation on ventilatory capacity and the extent of ventilatory limitation during exercise. METHODS Eleven asthmatics completed three exercise bouts on a cycle ergometer. Exercise was preceded by no treatment (trialCON), inhaled β2 agonist (trialBD), or a eucapnic voluntary hyperpnea challenge (trialBC). Maximal expiratory flow-volume maneuvers (MEFV) were performed before and within 40 s of exercise cessation. Exercise tidal flow-volume loops were placed within the preexercise and postexercise MEFV curve and used to determine expiratory flow limitation and maximum ventilatory capacity (V˙ECap). RESULTS Preexercise airway function was different among the trials (forced expiratory volume 1 s during trialCON, trialBD, and trialBC = 3.3 ± 0.8 L, 3.8 ± 0.8 L, and 2.9 ± 0.8 L, respectively; P < 0.05). Maximal expired airflow increased with exercise during all three trials, but the increase was greatest during trialBC (delta forced expiratory volume 1 s during trialCON, trialBD, and trialBC = +12.2% ± 13.1%, +5.2% ± 5.7%, +28.1% ± 15.7%). Thus, the extent of expiratory flow limitation decreased, and V˙ECap increased, when the postexercise MEFV curve was used. During trialCON and trialBC, actual exercise ventilation exceeded V˙ECap calculated with the preexercise MEFV curve in seven and nine subjects, respectively. CONCLUSIONS These findings demonstrate the critical importance of exercise bronchodilation in the asthmatic with narrowed airways. Of clinical relevance, the results also highlight the importance of assessing airway function during or immediately after exercise in asthmatic persons; otherwise, mechanical limitations to exercise ventilation will be overestimated.
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Affiliation(s)
- Matthew J Rossman
- Department of Integrative Physiology, University of Colorado-Boulder, Boulder, CO
| | - Greg Petrics
- Department of Environmental and Health Sciences, Northern Vermont University-Johnson, Johnson, VT
| | - Andrew Klansky
- Department of Environmental and Health Sciences, Northern Vermont University-Johnson, Johnson, VT
| | - Kasie Craig
- Department of Environmental and Health Sciences, Northern Vermont University-Johnson, Johnson, VT
| | - Charles G Irvin
- Departments of Medicine and Biophysics Pulmonary and Critical Care Medicine, University of Vermont, Burlington, VT
| | - Hans Christian Haverkamp
- Department of Nutrition and Exercise Physiology, Elson S. Floyd College of Medicine, Washington State University-Spokane Health Sciences, Spokane, WA
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Jalil Y, Damiani LF, Basoalto R, Bachmman MC, Bruhn A. A deep look into the rib cage compression technique in mechanically ventilated patients: a narrative review. Rev Bras Ter Intensiva 2022. [PMID: 35766667 PMCID: PMC9345587 DOI: 10.5935/0103-507x.20220012-en] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Defective management of secretions is one of the most frequent complications in invasive mechanically ventilated patients. Clearance of secretions through chest physiotherapy is a critical aspect of the treatment of these patients. Manual rib cage compression is one of the most practiced chest physiotherapy techniques in ventilated patients; however, its impact on clinical outcomes remains controversial due to methodological issues and poor understanding of its action. In this review, we present a detailed analysis of the physical principles involved in rib cage compression technique performance, as well as the physiological effects observed in experimental and clinical studies, which show that the use of brief and vigorous rib cage compression, based on increased expiratory flows (expiratory-inspiratory airflow difference of > 33L/minute), can improve mucus movement toward the glottis. On the other hand, the use of soft and gradual rib cage compression throughout the whole expiratory phase does not impact the expiratory flows, resulting in ineffective or undesired effects in some cases. More physiological studies are needed to understand the principles of the rib cage compression technique in ventilated humans. However, according to the evidence, rib cage compression has more potential benefits than risks, so its implementation should be promoted.
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Affiliation(s)
- Yorschua Jalil
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile - Santiago, Chile
- Corresponding author: Yorschua Jalil Departamento de Medicina Intensiva, Facultad de Medicina Pontificia Universidad Católica de Chile Av. Libertador Bernardo O’Higgins, 340 Santiago 8331150 Chile E-mail:
| | - L. Felipe Damiani
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile - Santiago, Chile
| | - Roque Basoalto
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile - Santiago, Chile
| | - María Consuelo Bachmman
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile - Santiago, Chile
| | - Alejandro Bruhn
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile - Santiago, Chile
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Barroso-García V, Jiménez-García J, Gutiérrez-Tobal GC, Hornero R. Airflow Analysis in the Context of Sleep Apnea. Advances in the Diagnosis and Treatment of Sleep Apnea 2022; 1384:241-253. [PMID: 36217088 DOI: 10.1007/978-3-031-06413-5_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The airflow (AF) is a physiological signal involved in the overnight polysomnography (PSG) that reflects the respiratory activity. This signal is able to show the particularities of sleep apnea and is therefore used to define apneic events. In this regard, a growing number of studies have shown the usefulness of employing the overnight airflow as the only or combined information source for diagnosing sleep apnea in both children and adults. Due to its easy acquisition and interpretation, this biosignal has been widely analyzed by means of different signal processing techniques. In this chapter, we review the main methodological approaches applied to characterize and extract relevant information from this signal. In view of the results, we can conclude that the overnight airflow successfully reflects the particularities caused by the occurrence of apneic and hypopneic events and provides useful information for obtaining relevant biomarkers that characterize this disease.
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Affiliation(s)
- Verónica Barroso-García
- Biomedical Engineering Group, University of Valladolid, Valladolid, Spain.
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Valladolid, Spain.
| | | | - Gonzalo C Gutiérrez-Tobal
- Biomedical Engineering Group, University of Valladolid, Valladolid, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Valladolid, Spain
| | - Roberto Hornero
- Biomedical Engineering Group, University of Valladolid, Valladolid, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Valladolid, Spain
- Mathematics Research Institute of the University of Valladolid (IMUVa), Valladolid, Spain
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Chen W, Wang L, Chen L, Ge H, Cui X. Numerical study of the impact of glottis properties on the airflow field in the human trachea using V-LES. Respir Physiol Neurobiol 2021; 295:103784. [PMID: 34517114 DOI: 10.1016/j.resp.2021.103784] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 08/31/2021] [Accepted: 09/03/2021] [Indexed: 01/13/2023]
Abstract
The influences of the profiles and cross-sectional areas of glottal aperture on the upper respiratory airway are investigated using an idealized cast-based mouth-throat model and three dimensional computational fluid dynamics (CFD). The open source CFD code OpenFOAM is employed. The transient flows are modeled using the very-large eddy simulation with the Smagorinsky sub-grid scale (SGS) model. Five different shapes of glottis are considered, including circular glottis with 100 %, 75 % and 50 % cross-sectional area and elliptic glottis with 75 % and 50 % cross-sectional area. Both instantaneous and averaged flow fields are analyzed. It is found that the variations of glottis have great impacts on the properties of downstream flow fields such as the secondary flow, laryngeal jet, recirculation zone, turbulent kinetic energy, and vortex. Evident impacts are observed in the region within 6 tracheal diameters downstream of the glottis. The profile of the glottis has more impacts on the laryngeal shape, while the cross-sectional area has more impacts on velocity of the laryngeal jet and turbulent intensity. It is concluded that both the glottal areas and profiles are critical for an idealized geometrical mouth-throat model.
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Affiliation(s)
- Wenjuan Chen
- School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Li Wang
- School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Liang Chen
- First Affiliated Hospital of Zhejiang University, Zhejiang University, Hangzhou, China
| | - Haiwen Ge
- Department of Mechanical Engineering, Texas Tech University, Lubbock, TX, USA.
| | - Xinguang Cui
- School of Aerospace Engineering, Huazhong University of Science and Technology, Wuhan, China.
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Pigatto AV, Kao TJ, Mueller JL, Baker CD, DeBoer EM, Kupfer O. Electrical impedance tomography detects changes in ventilation after airway clearance in spinal muscular atrophy type I. Respir Physiol Neurobiol 2021; 294:103773. [PMID: 34400355 DOI: 10.1016/j.resp.2021.103773] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 04/06/2021] [Accepted: 08/05/2021] [Indexed: 11/18/2022]
Abstract
The effect of mechanical insufflation-exsufflation (MIE) for airway clearance in patients with spinal muscular atrophy type I (SMA-I) on the distribution of ventilation in the lung is unknown, as is the duration of its beneficial effects. A pilot study to investigate the feasibility of using three dimensional (3-D) electrical impedance tomography (EIT) images to estimate lung volumes pre- and post-MIE for assessing the effectiveness of mechanical insufflation-exsufflation (MIE) was conducted in 6 pediatric patients with SMA-I in the neuromuscular clinic at Children's Hospital Colorado. EIT data were collected before, during, and after the MIE procedure on two rows of 16 electrodes placed around the chest. Lung volumes were computed from the images and compared before, during, and after the MIE procedure to assess the ability of EIT to estimate changes in lung volume during insufflation and exsufflation. Images of pulsatile pulmonary perfusion were computed in subjects able to perform breath-holding. In four of the six subjects, lung volumes during tidal breathing increased after MIE (average change from pre to post MIE was 58.8±55.1 mL). The time-dependent plots of lung volume computed from the EIT data clearly show when the MIE device insufflates and exsufflates air and the rest periods between mechanical coughs. Images of pulmonary pulsatile perfusion were computed from data collected during breathing pauses. The results suggest that EIT holds promise for estimating lung volumes and ventilation/perfusion mismatch, both of which are useful for assessing the effectiveness of MIE in clearing mucus plugs.
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Affiliation(s)
- Andre Viera Pigatto
- School of Biomedical Engineering, Colorado State University, Fort Collins, CO 80523, United States
| | - Tzu-Jen Kao
- GE Research, Niskayuna, NY 12309, United States
| | - Jennifer L Mueller
- School of Biomedical Engineering and Department of Mathematics, Colorado State University, Fort Collins, CO 80523, United States.
| | - Christopher D Baker
- Department of Pediatrics, Section of Pulmonary Medicine, University of Colorado School of Medicine, Aurora, CO 80045, United States
| | - Emily M DeBoer
- Department of Pediatrics, Section of Pulmonary Medicine, University of Colorado School of Medicine, Aurora, CO 80045, United States
| | - Oren Kupfer
- Department of Pediatrics, Section of Pulmonary Medicine, University of Colorado School of Medicine, Aurora, CO 80045, United States
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Ozkaya O, Balci GA, As H, Yildiztepe E. A new technique to analyse threshold-intensities based on time dependent change-points in the ratio of minute ventilation and end-tidal partial pressure of carbon-dioxide production. Respir Physiol Neurobiol 2021; 294:103735. [PMID: 34229064 DOI: 10.1016/j.resp.2021.103735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 06/18/2021] [Accepted: 07/01/2021] [Indexed: 11/19/2022]
Abstract
The aim of this study was to test the utility and effectiveness of an alternative computational approach to threshold-intensities based on time dependent change-points in minute ventilation divided by end-tidal partial pressure of CO2 (VE/PETCO2) to reveal whether respiratory compensation point (RCP) is a third ventilatory threshold, or not. Ten recreationally active young adults and ten well-trained athletes volunteered to take part in this study. Following incremental ramp tests, gas exchange threshold (GET) and respiratory compensation point (RCP) were respectively evaluated by the slopes of VCO2-VO2 and VE-VCO2 using the Innocor system automatically. Respiratory threshold (RT) was analysed based on time dependent change-points in the VE/PETCO2 using binary segmentation algorithm. Additionally, those intersections were analysed independently by two experienced investigators using a visual identification technique in a double-blind design. According to the results, in the recreationally active group, there were the first (GET1) and the second (GET2) gas exchange thresholds which were identical with the RT1 (139 W; 1.9 L⋅min-1 of VO2; 1.73 L⋅min-1 of VCO2; 49.9 L⋅min-1 of VE versus 139 W; 1.88 L⋅min-1; 1.7 L⋅min-1; 49 L⋅min-1, respectively) and RT2 (186 W; 2.39 L⋅min-1 of VO2; 2.44 L⋅min-1 of VCO2; 66 L⋅min-1 of VE versus 187 W; 2.41 L⋅min-1; 2.49 L⋅min-1; 65.7 L⋅min-1, respectively). However, there were three threshold intensities which were determined by GET1, GET2, and RCP in well-trained athletes. Additionally, RT1, RT2, and RT3 were determined as valid surrogates of the GET1 (194 W; 2.56 L⋅min-1 of VO2; 1.99 L⋅min-1 of VCO2; 57.5 L⋅min-1 of VE versus 192 W; 2.61 L⋅min-1; 1.99 Lmin-1; 57.7 L⋅min-1, respectively), GET2 (267 W; 3.6 L⋅min-1 of VO2; 3.29 L⋅min-1 of VCO2; 94.5 L⋅min-1 of VE versus 266 W; 3.58 L⋅min-1; 3.26 L⋅min-1; 93.4 L⋅min-1, respectively), and RCP (324 W; 4.05 L⋅min-1 of VO2; 4.13 L⋅min-1 of VCO2; 124 L⋅min-1 of VE versus 322 W; 4.02 L⋅min-1; 4.07 L⋅min-1; 122 L⋅min-1, respectively) in well-trained athletes. There were high levels of agreements between the power outputs determined by traditional techniques and newly proposed change-points in RT. All markers were strongly correlated (p < 0.001). It was shown that RT technique can provide an accurate threshold determination. Furthermore, the RCP was observed as a third threshold-intensity for well-trained athletes but not for recreationally active young adults.
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Affiliation(s)
- Ozgur Ozkaya
- Department of Coaching Education, Faculty of Sport Sciences, Ege University, 35050, Bornova, Izmir, Turkey.
| | - Gorkem A Balci
- Department of Coaching Education, Faculty of Sport Sciences, Ege University, 35050, Bornova, Izmir, Turkey
| | - Hakan As
- Department of Sports and Health Sciences, Institution of Health Sciences, Ege University, 35050, Bornova, Izmir, Turkey
| | - Engin Yildiztepe
- Department of Statistics, Faculty of Science, Dokuz Eylul University, 35390, Buca, Izmir, Turkey
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Ljimani A, Hojdis M, Stabinska J, Valentin B, Frenken M, Appel E, Antoch G, Wittsack HJ. Analysis of different image-registration algorithms for Fourier decomposition MRI in functional lung imaging. Acta Radiol 2021; 62:875-881. [PMID: 32727212 DOI: 10.1177/0284185120944902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Motion correction is mandatory for the functional Fourier decomposition magnetic resonance imaging (FD-MRI) of the lungs. Therefore, it is important to evaluate the quality of various image-registration algorithms for pulmonary FD-MRI and to determine their impact on FD-MRI outcome. PURPOSE To evaluate different image-registration algorithms for FD-MRI in functional lung imaging. MATERIAL AND METHODS Fifteen healthy volunteers were examined in a 1.5-T whole-body MR scanner (Magnetom Avanto, Siemens AG) with a non-contrast enhanced 2D TrueFISP pulse sequence in coronal view and free-breathing (acquisition time 45 s, 250 images). Three image-registration algorithms were used to compensate the spatial variation of the lungs (fMRLung 3.0, ANTs, and Elastix). Quality control for image registration was performed by edge detection (ED), quotient image criterion (QI), and dice similarity coefficient (DSC). Ventilation, perfusion, and a ventilation/perfusion quotient (V/Q) were calculated using the three registered datasets. RESULTS Average computing times for the three image-registration algorithms were 1.0 ± 1.6 min, 38.0 ± 13.5 min, and 354 ± 78 min for fMRLung, ANTs, and Elastix, respectively. No significant difference in the quality of motion correction provided by different image-registration algorithms occurred. Significant differences were observed between fMRLung- and Elastix-based perfusion values of the left lung as well as fMRLung- and ANTs-based V/Q quotient of the right and the entire lung (P < 0.05). Other ventilation and perfusion values were not significantly different. CONCLUSION The mandatory motion correction for functional FD-MRI of the lung can be achieved through different image-registration algorithms with consistent quality. However, a significantly difference in computing time between the image-registration algorithms still requires an optimization.
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Affiliation(s)
- Alexandra Ljimani
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
| | - Malte Hojdis
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
| | - Julia Stabinska
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
| | - Birte Valentin
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
| | - Miriam Frenken
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
| | - Elisabeth Appel
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
| | - Gerald Antoch
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
| | - Hans-Jörg Wittsack
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
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Abstract
INTRODUCTION We determined the recovery from neuromuscular fatigue in six professional (PRO) and seven moderately trained (MOD) cyclists after repeated cycling time trials of various intensities/durations. METHOD Participants performed two 1-min (1minTT) or two 10-min (10minTT) self-paced cycling time trials with 5 min of recovery in between. Central and peripheral fatigue were quantified via preexercise to postexercise (15-s through 15-min recovery) changes in voluntary activation (VA) and potentiated twitch force. VA was measured using the interpolated twitch technique, and potentiated twitch force was evoked by single (QTsingle) and paired (10-Hz (QT10) and 100-Hz (QT100)) electrical stimulations of the femoral nerve. RESULTS Mean power output was 32%-72% higher during all the time trials and decreased less (-10% vs -13%) from the first to second time trial in PRO compared with MOD (P < 0.05). Conversely, exercise-induced reduction in QTsingle and QT10/QT100 was significantly lower in PRO after every time trial (P < 0.05). Recovery from fatigue from 15 s to 2 min for QTsingle and QT10/QT100 was slower in PRO after every time trial (P < 0.05). In both groups, the reduction in QTsingle was lower after the 10minTTs compared with 1minTTs (P < 0.05). Conversely, VA decreased more after the 10minTTs compared with 1minTTs (P < 0.05). CONCLUSION Our findings showed that excitation-contraction coupling was preserved after exercise in PRO compared with MOD. This likely contributed to the improved performance during repeated cycling time trials of various intensity/duration in PRO, despite a slower rate of recovery in its early phase. Finally, the time course of recovery from neuromuscular fatigue in PRO was dependent on the effects of prolonged low-frequency force depression.
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Zuccarelli L, Sartorio A, DE Micheli R, Tringali G, Grassi B. Obese Patients Decrease Work Rate in Order to Keep a Constant Target Heart Rate. Med Sci Sports Exerc 2021; 53:986-993. [PMID: 33148969 DOI: 10.1249/mss.0000000000002551] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE "Slow components" of heart rate (HR) kinetics, occurring also during moderate-intensity constant work rate exercise, represent a problem for exercise prescription at fixed HR values. This problem, described in young healthy subjects, could be more pronounced in obese patients. METHODS Sixteen male obese patients (age, 22 ± 7 yr; body mass, 127 ± 19 kg; body mass index, 41.6 ± 3.9 kg·m-2) were tested before (PRE) and after (POST) a 3-wk multidisciplinary body mass reduction program, entailing moderate-intensity exercise. They performed on a cycle ergometer an incremental exercise to voluntary exhaustion (to determine peak pulmonary oxygen uptake (V˙O2peak) and gas exchange threshold (GET)) and constant work rate exercises: moderate-intensity (MODERATE; 80% of GET determined in PRE), heavy-intensity (HEAVY; 120% of GET determined in PRE), and "HRCLAMPED" exercise, in which work rate was continuously adjusted to maintain a constant HR corresponding to that at 120% of GET. Breath-by-breath V˙O2 and HR were determined. RESULTS V˙O2peak and GET (expressed as a percent of V˙O2peak) were not significantly different in PRE versus POST. In POST versus PRE, the HR slow component disappeared (MODERATE) or was reduced (HEAVY). In PRE, work rate had to decrease by ~20% over a 15-min task in order to keep HR constant; this decrease was significantly smaller (~5%) in POST. CONCLUSIONS In obese patients, a 3-wk multidisciplinary body mass reduction intervention i) increased exercise tolerance by eliminating (during MODERATE) or by reducing (during HEAVY) the slow component of HR kinetics, and ii) facilitated exercise prescription by allowing to translate a fixed submaximal HR value into a work rate slightly above GET.
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Affiliation(s)
| | | | - Roberta DE Micheli
- Experimental Laboratory for Auxo-endocrinological Research, Istituto Auxologico Italiano, IRCCS, Milan and Piancavallo (VB), ITALY
| | - Gabriella Tringali
- Experimental Laboratory for Auxo-endocrinological Research, Istituto Auxologico Italiano, IRCCS, Milan and Piancavallo (VB), ITALY
| | - Bruno Grassi
- Department of Medicine, University of Udine, Udine, ITALY
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Shein SL, Whitticar S, Mascho KK, Pace E, Speicher R, Deakins K. The effects of wearing facemasks on oxygenation and ventilation at rest and during physical activity. PLoS One 2021; 16:e0247414. [PMID: 33626065 PMCID: PMC7904135 DOI: 10.1371/journal.pone.0247414] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 02/05/2021] [Indexed: 12/15/2022] Open
Abstract
Background Facemasks are recommended to reduce the spread of SARS-CoV-2, but concern about inadequate gas exchange is an often cited reason for non-compliance. Research question Among adult volunteers, do either cloth masks or surgical masks impair oxygenation or ventilation either at rest or during physical activity? Study design and methods With IRB approval and informed consent, we measured heart rate (HR), transcutaneous carbon dioxide (CO2) tension and oxygen levels (SpO2) at the conclusion of six 10-minute phases: sitting quietly and walking briskly without a mask, sitting quietly and walking briskly while wearing a cloth mask, and sitting quietly and walking briskly while wearing a surgical mask. Brisk walking required at least a 10bpm increase in heart rate. Occurrences of hypoxemia (decrease in SpO2 of ≥3% from baseline to a value of ≤94%) and hypercarbia (increase in CO2 tension of ≥5 mmHg from baseline to a value of ≥46 mmHg) in individual subjects were collected. Wilcoxon signed-rank was used for pairwise comparisons among values for the whole cohort (e.g. walking without a mask versus walking with a cloth mask). Results Among 50 adult volunteers (median age 33 years; 32% with a co-morbidity), there were no episodes of hypoxemia or hypercarbia (0%; 95% confidence interval 0–1.9%). In paired comparisons, there were no statistically significant differences in either CO2 or SpO2 between baseline measurements without a mask and those while wearing either kind of mask mask, both at rest and after walking briskly for ten minutes. Interpretation The risk of pathologic gas exchange impairment with cloth masks and surgical masks is near-zero in the general adult population.
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Affiliation(s)
- Steven L. Shein
- Division of Pediatric Critical Care Medicine, Rainbow Babies and Children’s Hospital, Cleveland, Ohio, United States of America
- * E-mail:
| | - Sofie Whitticar
- Department of Pediatrics, Rainbow Babies and Children’s Hospital, Cleveland, Ohio, United States of America
| | - Kira K. Mascho
- Division of Pediatric Critical Care Medicine, Rainbow Babies and Children’s Hospital, Cleveland, Ohio, United States of America
| | - Elizabeth Pace
- Division of Pediatric Critical Care Medicine, Rainbow Babies and Children’s Hospital, Cleveland, Ohio, United States of America
| | - Richard Speicher
- Division of Pediatric Critical Care Medicine, Rainbow Babies and Children’s Hospital, Cleveland, Ohio, United States of America
| | - Kathleen Deakins
- Department of Respiratory Care, Rainbow Babies and Children’s Hospital, Cleveland, Ohio, United States of America
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Weber J, Mißbach C, Schmidt J, Wenzel C, Schumann S, Philip JH, Wirth S. Prediction of expiratory desflurane and sevoflurane concentrations in lung-healthy patients utilizing cardiac output and alveolar ventilation matched pharmacokinetic models: A comparative observational study. Medicine (Baltimore) 2021; 100:e23570. [PMID: 33578509 PMCID: PMC7886476 DOI: 10.1097/md.0000000000023570] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Accepted: 11/04/2020] [Indexed: 01/05/2023] Open
Abstract
The Gas Man simulation software provides an opportunity to teach, understand and examine the pharmacokinetics of volatile anesthetics. The primary aim of this study was to investigate the accuracy of a cardiac output and alveolar ventilation matched Gas Man model and to compare its predictive performance with the standard pharmacokinetic model using patient data.Therefore, patient data from volatile anesthesia were successively compared to simulated administration of desflurane and sevoflurane for the standard and a parameter-matched simulation model with modified alveolar ventilation and cardiac output. We calculated the root-mean-square deviation (RMSD) between measured and calculated induction, maintenance and elimination and the expiratory decrement times during emergence and recovery for the standard and the parameter-matched model.During induction, RMSDs for the standard Gas Man simulation model were higher than for the parameter-matched Gas Man simulation model [induction (desflurane), standard: 1.8 (0.4) % Atm, parameter-matched: 0.9 (0.5) % Atm., P = .001; induction (sevoflurane), standard: 1.2 (0.9) % Atm, parameter-matched: 0.4 (0.4) % Atm, P = .029]. During elimination, RMSDs for the standard Gas Man simulation model were higher than for the parameter-matched Gas Man simulation model [elimination (desflurane), standard: 0.7 (0.6) % Atm, parameter-matched: 0.2 (0.2) % Atm, P = .001; elimination (sevoflurane), standard: 0.7 (0.5) % Atm, parameter-matched: 0.2 (0.2) % Atm, P = .008]. The RMSDs during the maintenance of anesthesia and the expiratory decrement times during emergence and recovery showed no significant differences between the patient and simulated data for both simulation models.Gas Man simulation software predicts expiratory concentrations of desflurane and sevoflurane in humans with good accuracy, especially when compared to models for intravenous anesthetics. Enhancing the standard model by ventilation and hemodynamic input variables increases the predictive performance of the simulation model. In most patients and clinical scenarios, the predictive performance of the standard Gas Man simulation model will be high enough to estimate pharmacokinetics of desflurane and sevoflurane with appropriate accuracy.
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Affiliation(s)
- Jonas Weber
- Department of Anesthesiology and Critical Care, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Claudia Mißbach
- Department of Anesthesiology and Critical Care, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Johannes Schmidt
- Department of Anesthesiology and Critical Care, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christin Wenzel
- Department of Anesthesiology and Critical Care, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Stefan Schumann
- Department of Anesthesiology and Critical Care, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - James H. Philip
- Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Steffen Wirth
- Department of Anesthesiology and Critical Care, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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Constantini K, Bouillet AC, Wiggins CC, Martin BJ, Chapman RF. Ventilatory Responsiveness during Exercise and Performance Impairment in Acute Hypoxia. Med Sci Sports Exerc 2021; 53:295-305. [PMID: 32694376 PMCID: PMC8058857 DOI: 10.1249/mss.0000000000002466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION An adequate increase in minute ventilation to defend arterial oxyhemoglobin saturation (SpO2) during hypoxic exercise is commonly viewed as an important factor contributing to large inter-individual variations in the degree of exercise performance impairment in hypoxia. Although the hypoxic ventilatory response (HVR) could provide insight into the underpinnings of such impairments, it is typically measured at rest under isocapnic conditions. Thus, we aimed to determine whether 1) HVR at rest and during exercise are similar and 2) exercise HVR is related to the degree of impairment in cycling time trial (TT) performance from normoxia to acute hypoxia (∆TT). METHODS Sixteen endurance-trained men (V˙O2peak, 62.5 ± 5.8 mL·kg-1·min-1) performed two poikilocapnic HVR tests: one during seated rest (HVRREST) and another during submaximal cycling (HVREX). On two separate visits, subjects (n = 12) performed a 10-km cycling TT while breathing either room air (FiO2 = 0.21) or hypoxic gas mixture (FiO2 = 0.16) in a randomized order. RESULTS HVREX was significantly (P < 0.001) greater than HVRREST (1.52 ± 0.47 and 0.22 ± 0.13 L·min-1·%SpO2-1, respectively), and these measures were not correlated (r = -0.16, P = 0.57). ∆TT was not correlated with HVRREST (P = 0.70) or HVREX (P = 0.54), but differences in ventilation and end-tidal CO2 between hypoxic and normoxic TT and the ventilatory equivalent for CO2 during normoxic TT explained ~85% of the variance in performance impairment in acute hypoxia (P < 0.01). CONCLUSION We conclude that 1) HVR is not an appropriate measure to predict the exercise ventilatory response or performance impairments in acute hypoxia and 2) an adequate and metabolically matched increase in exercise ventilation, but not the gain in the ventilatory response to hypoxia, is essential for mitigating hypoxia-induced impairments in endurance cycling performance.
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Affiliation(s)
| | - Anna C Bouillet
- Department of Kinesiology, Indiana University, Bloomington, IN
| | - Chad C Wiggins
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN
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Abstract
Online supplemental material is available for this article.
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Affiliation(s)
- Soon Ho Yoon
- From the Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, 101, DAEHAK-RO JONGNO-GU, SEOUL 03080, Korea (S.H.Y.), School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, LE11 3TU, UK (M.K.)
| | - Minsuok Kim
- From the Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, 101, DAEHAK-RO JONGNO-GU, SEOUL 03080, Korea (S.H.Y.), School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, LE11 3TU, UK (M.K.)
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Safaee Fakhr B, Araujo Morais CC, De Santis Santiago RR, Di Fenza R, Gibson LE, Restrepo PA, Chang MG, Bittner EA, Pinciroli R, Fintelmann FJ, Kacmarek RM, Berra L. Bedside monitoring of lung perfusion by electrical impedance tomography in the time of COVID-19. Br J Anaesth 2020; 125:e434-e436. [PMID: 32859359 PMCID: PMC7413127 DOI: 10.1016/j.bja.2020.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 08/02/2020] [Indexed: 02/07/2023] Open
Affiliation(s)
- Bijan Safaee Fakhr
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Caio C Araujo Morais
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Roberta R De Santis Santiago
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Raffaele Di Fenza
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Lauren E Gibson
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Paula A Restrepo
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Marvin G Chang
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Edward A Bittner
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Riccardo Pinciroli
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Florian J Fintelmann
- Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Robert M Kacmarek
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Respiratory Care Department, Massachusetts General Hospital, Boston, MA, USA
| | - Lorenzo Berra
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Respiratory Care Department, Massachusetts General Hospital, Boston, MA, USA.
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22
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Strozza D, Wilhite DP, Babb TG, Bhammar DM. Pitfalls in Expiratory Flow Limitation Assessment at Peak Exercise in Children: Role of Thoracic Gas Compression. Med Sci Sports Exerc 2020; 52:2310-2319. [PMID: 33064406 PMCID: PMC7573195 DOI: 10.1249/mss.0000000000002378] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Thoracic gas compression and exercise-induced bronchodilation can influence the assessment of expiratory flow limitation (EFL) during cardiopulmonary exercise tests. The purpose of this study was to examine the effect of thoracic gas compression and exercise-induced bronchodilation on the assessment of EFL in children with and without obesity. METHODS Forty children (10.7 ± 1.0 yr; 27 obese; 15 with EFL) completed pulmonary function tests and incremental exercise tests. Inspiratory capacity maneuvers were performed during the incremental exercise test for the placement of tidal flow volume loops within the maximal expiratory flow volume (MEFV) loops, and EFL was calculated as the overlap between the tidal and the MEFV loops. MEFV loops were plotted with volume measured at the lung using plethysmography (MEFVp), with volume measured at the mouth using spirometry concurrent with measurements in the plethysmograph (MEFVm), and from spirometry before (MEFVpre) and after (MEFVpost) the incremental exercise test. Only the MEFVp loops were corrected for thoracic gas compression. RESULTS Not correcting for thoracic gas compression resulted in incorrect diagnosis of EFL in 23% of children at peak exercise. EFL was 26% ± 15% VT higher for MEFVm compared with MEFVp (P < 0.001), with no differences between children with and without obesity (P = 0.833). The difference in EFL estimation using MEFVpre (37% ± 30% VT) and MEFVpost (31% ± 26% VT) did not reach statistical significance (P = 0.346). CONCLUSIONS Not correcting the MEFV loops for thoracic gas compression leads to the overdiagnosis and overestimation of EFL. Because most commercially available metabolic measurement systems do not correct for thoracic gas compression during spirometry, there may be a significant overdiagnosis of EFL in cardiopulmonary exercise testing. Therefore, clinicians must exercise caution while interpreting EFL when the MEFV loop is derived through spirometry.
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Affiliation(s)
- Danielle Strozza
- School of Medicine, University of Nevada Las Vegas, Las Vegas, NV
| | - Daniel P. Wilhite
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and UT Southwestern Medical Center, Dallas, TX
| | - Tony G. Babb
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and UT Southwestern Medical Center, Dallas, TX
| | - Dharini M. Bhammar
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and UT Southwestern Medical Center, Dallas, TX
- Department of Kinesiology and Nutrition Sciences, School of Integrated Health Sciences, University of Nevada Las Vegas, Las Vegas, NV
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23
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Bonny V, Janiak V, Spadaro S, Pinna A, Demoule A, Dres M. Effect of PEEP decremental on respiratory mechanics, gasses exchanges, pulmonary regional ventilation, and hemodynamics in patients with SARS-Cov-2-associated acute respiratory distress syndrome. Crit Care 2020; 24:596. [PMID: 33023638 PMCID: PMC7538032 DOI: 10.1186/s13054-020-03311-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 09/24/2020] [Indexed: 11/10/2022] Open
Affiliation(s)
- Vincent Bonny
- Sorbonne Université, INSERM, UMRS1158 Neurophysiologie respiratoire expérimentale et clinique, Paris, France.
| | - Vincent Janiak
- Sorbonne Université, UPMC Univ Paris 06, INSERM, Sorbonne Paris Cité, Université Paris 13, LIMICS, UMR_S 1142, Paris, France
- Bioserenity, 20 rue Berbier-du-Mets, 75013, Paris, France
| | - Savino Spadaro
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
- Anaesthesia and Intensive Care Unit, Sant'Anna Hospital, Aldo Moro, Ferrara, Italy
| | - Andrea Pinna
- Sorbonne Université, UPMC Univ Paris 06, INSERM, Sorbonne Paris Cité, Université Paris 13, LIMICS, UMR_S 1142, Paris, France
| | - Alexandre Demoule
- Sorbonne Université, INSERM, UMRS1158 Neurophysiologie respiratoire expérimentale et clinique, Paris, France
- AP-HP. Sorbonne Université, Hôpital Pitié-Salpêtrière, Service de Pneumologie, Médecine intensive - Réanimation (Département "R3S"), F-75013, Paris, France
| | - Martin Dres
- Sorbonne Université, INSERM, UMRS1158 Neurophysiologie respiratoire expérimentale et clinique, Paris, France
- AP-HP. Sorbonne Université, Hôpital Pitié-Salpêtrière, Service de Pneumologie, Médecine intensive - Réanimation (Département "R3S"), F-75013, Paris, France
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24
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He H, Chi Y, Long Y, Yuan S, Frerichs I, Möller K, Fu F, Zhao Z. Influence of overdistension/recruitment induced by high positive end-expiratory pressure on ventilation-perfusion matching assessed by electrical impedance tomography with saline bolus. Crit Care 2020; 24:586. [PMID: 32993811 PMCID: PMC7523261 DOI: 10.1186/s13054-020-03301-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 09/21/2020] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND High positive end-expiratory pressures (PEEP) may induce overdistension/recruitment and affect ventilation-perfusion matching (VQMatch) in mechanically ventilated patients. This study aimed to investigate the association between PEEP-induced lung overdistension/recruitment and VQMatch by electrical impedance tomography (EIT). METHODS The study was conducted prospectively on 30 adult mechanically ventilated patients: 18/30 with ARDS and 12/30 with high risk for ARDS. EIT measurements were performed at zero end-expiratory pressures (ZEEP) and subsequently at high (12-15 cmH2O) PEEP. The number of overdistended pixels over the number of recruited pixels (O/R ratio) was calculated, and the patients were divided into low O/R (O/R ratio < 15%) and high O/R groups (O/R ratio ≥ 15%). The global inhomogeneity (GI) index was calculated to evaluate the ventilation distribution. Lung perfusion image was calculated from the EIT impedance-time curves caused by 10 ml 10% NaCl injection during a respiratory pause (> 8 s). DeadSpace%, Shunt%, and VQMatch% were calculated based on lung EIT perfusion and ventilation images. RESULTS Increasing PEEP resulted in recruitment mainly in dorsal regions and overdistension mainly in ventral regions. ΔVQMatch% (VQMatch% at high PEEP minus that at ZEEP) was significantly correlated with recruited pixels (r = 0.468, P = 0.009), overdistended pixels (r = - 0.666, P < 0.001), O/R ratio (r = - 0.686, P < 0.001), and ΔSpO2 (r = 0.440, P = 0.015). Patients in the low O/R ratio group (14/30) had significantly higher Shunt% and lower VQMatch% than those in the high O/R ratio group (16/30) at ZEEP but not at high PEEP. Comparable DeadSpace% was found in both groups. A high PEEP caused a significant improvement of VQMatch%, DeadSpace%, Shunt%, and GI in the low O/R ratio group, but not in the high O/R ratio group. Using O/R ratio of 15% resulted in a sensitivity of 81% and a specificity of 100% for an increase of VQMatch% > 20% in response to high PEEP. CONCLUSIONS Change of ventilation-perfusion matching was associated with regional overdistention and recruitment induced by PEEP. A low O/R ratio induced by high PEEP might indicate a more homogeneous ventilation and improvement of VQMatch. TRIAL REGISTRATION ClinicalTrials.gov, NCT04081155 . Registered on 9 September 2019-retrospectively registered.
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Affiliation(s)
- Huaiwu He
- Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Yi Chi
- Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Yun Long
- Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
| | - Siyi Yuan
- Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China
| | - Inéz Frerichs
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center of Schleswig-Holstein Campus kiel, Kiel 24105, Germany
| | - Knut Möller
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
| | - Feng Fu
- Department of Biomedical Engineering, Fourth Military Medical University, 169 Changle Xi Rd, Xi'an, China
| | - Zhanqi Zhao
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany.
- Department of Biomedical Engineering, Fourth Military Medical University, 169 Changle Xi Rd, Xi'an, China.
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25
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Berger M, Pillei M, Mehrle A, Recheis W, Kral F, Kraxner M, Bardosi Z, Freysinger W. Nasal cavity airflow: Comparing laser doppler anemometry and computational fluid dynamic simulations. Respir Physiol Neurobiol 2020; 283:103533. [PMID: 32889096 DOI: 10.1016/j.resp.2020.103533] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 08/15/2020] [Accepted: 08/21/2020] [Indexed: 11/19/2022]
Abstract
Objective parameters to assess the physical flow conditions of breathing are scarce and decisions for surgery, e.g. nasal septum correction, mainly rely on subjective surgeon judgment. To define decision supporting parameters, we compare laser Doppler anemometry (LDA) and numerical computational fluid dynamic simulations (CFD) of the airflow velocity vector fields in the nasal cavity, including lattice Boltzmann (LB) and finite volume methods (FVM). The simulations are based on an anonymous patient CT dataset with septal deviation. LDA measurements are preformed using a 3D printed model. Nasal airflow geometry is randomly deformed in order to approximate surgical changes. The root-mean-square velocity error near the nasal valve of laser Doppler anemometry and lattice Boltzmann simulations is 0.071. Changes in geometry similarly affect both measurement and simulation.
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Affiliation(s)
- M Berger
- Dept. of Environmental, Process & Energy Engineering, MCI - The Entrepreneurial School, Austria; Univ. Hospital of Otorhinolaryngology, Medical University Innsbruck, Austria.
| | - M Pillei
- Dept. of Environmental, Process & Energy Engineering, MCI - The Entrepreneurial School, Austria; Dept. of Fluid Mechanics, Friedrich-Alexander University Erlangen-Nuremberg, Germany.
| | - A Mehrle
- Dept. of Mechatronics, MCI - The Entrepreneurial School, Austria.
| | - W Recheis
- Univ. Hospital of Radiology, Medical University Innsbruck, Austria.
| | - F Kral
- Univ. Hospital of Otorhinolaryngology, Medical University Innsbruck, Austria; Dept. of ENT, Kardinal Schwarzenberg Hospital, Schwarzach im Pongau, Austria.
| | - M Kraxner
- Dept. of Environmental, Process & Energy Engineering, MCI - The Entrepreneurial School, Austria.
| | - Z Bardosi
- Univ. Hospital of Otorhinolaryngology, Medical University Innsbruck, Austria.
| | - W Freysinger
- Univ. Hospital of Otorhinolaryngology, Medical University Innsbruck, Austria.
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Barbieri JF, Gáspari AF, Teodoro CL, Motta L, Castaño LAA, Bertuzzi R, Bernades CF, Chacon-Mikahil MPT, de Moraes AC. The effect of an airflow restriction mask (ARM) on metabolic, ventilatory, and electromyographic responses to continuous cycling exercise. PLoS One 2020; 15:e0237010. [PMID: 32780739 PMCID: PMC7418989 DOI: 10.1371/journal.pone.0237010] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 07/17/2020] [Indexed: 11/30/2022] Open
Abstract
This study analyzed the physiological adjustments caused by the use of the Elevation training mask® (2.0), an airflow restriction mask (ARM) during continuous exercise. Eighteen physically active participants (12 men and 6 women) were randomized to two protocols: continuous exercise with mask (CE-ARM) and continuous exercise without mask (CE). Exercise consisted of cycling for 20 minutes at 60% of maximum power. Metabolic variables, lactate, and gas concentration were obtained from arterialized blood samples at pre and post exercise. Continuous expired gases and myoelectric activity of the quadriceps were performed at rest and during the test. We observed no reduction in oxygen saturation in CE-ARM, leading to lower pH, higher carbon dioxide, and greater hematocrit (all p <0.05). The expired gas analysis shows that the CE-ARM condition presented higher oxygen uptake and expired carbon dioxide concentrations (p <0.05). The CE-ARM condition also presented lower ventilatory volume, ventilatory frequency, and expired oxygen pressure (p <0.05). No changes in electromyography activity and lactate concentrations were identified. We conclude that using ARM does not induce hypoxia and represents an additional challenge for the control of acid-base balance, and we suggest the use of ARM as being suitable for respiratory muscle training.
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Affiliation(s)
- João Francisco Barbieri
- Department of Sport Science, School of Physical Education, University of Campinas, Campinas, Brazil
- * E-mail:
| | - Arthur Fernandes Gáspari
- Department of Sport Science, School of Physical Education, University of Campinas, Campinas, Brazil
| | - Cassia Lopes Teodoro
- Department of Sport Science, School of Physical Education, University of Campinas, Campinas, Brazil
| | - Leonardo Motta
- Department of Sport Science, School of Physical Education, University of Campinas, Campinas, Brazil
| | | | - Romulo Bertuzzi
- Endurance Performance Research (GEDAE-USP), School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | | | | | - Antonio Carlos de Moraes
- Department of Sport Science, School of Physical Education, University of Campinas, Campinas, Brazil
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27
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Feitosa WG, Barbosa TM, Correia RDA, Castro FADS. Is V̇O 2peak a Valid Estimation of V̇O 2max in Swimmers with Physical Impairments? Res Q Exerc Sport 2020; 91:252-262. [PMID: 31718516 DOI: 10.1080/02701367.2019.1660758] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 08/21/2019] [Indexed: 06/10/2023]
Abstract
Purpose: Peak and maximal oxygen uptake ([Formula: see text] and [Formula: see text], respectively) are used in assessing aerobic power. For swimmers with physical impairments, it is unclear whether the physiological variables obtained in 200-m and Nx200-m tests are similar. The objective of this study is to assess the validity of [Formula: see text] as an estimator of [Formula: see text] and complementary physiological variables, in particular, carbon dioxide production ([Formula: see text]), respiratory exchange ratio (RER), minute-ventilation ([Formula: see text] and absolute (HR) and relative (%HRmax) heart rates-which were obtained in a time trial test (200-m) and an incremental intermittent test (Nx200-m) performed by swimmers with physical impairments. Methods: Eleven well-trained swimmers with physical impairments performed 200-m all-out and Nx200-m from low to all-out (controlled by a visual pacer), both with a respiratory valve system and a portable gas analyzer. Results: A paired Student's t-test showed no statistical difference (p > .05) for all comparisons. The intraclass correlation coefficient (ICC) was 0.97 and 0.98 for [Formula: see text] in l/min and ml/kg/min, respectively; ICC = 0.75 to 0.9 for [Formula: see text] (l/min and ml/kg/min),[Formula: see text] (in l/min) and HR (beats/min); ICC = 0.5 and 0.75 for %HRmax; and ICC < 0.5 for RER. Passing-Bablok regression showed that the dispersions were acceptable, considering the proportionality, except for HR and %HRmax. Bland-Altman method showed a high level of agreement for all variables. Conclusions: The [Formula: see text] and [Formula: see text], as well as the physiological variables [Formula: see text] and HR obtained, respectively, by 200-m and Nx200-m tests in swimmers with physical impairment were not different.
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Affiliation(s)
| | - Tiago M Barbosa
- Nanyang Technological University
- Polytechnic Institute of Bragança
- Research Centre in Sports Health and Human Develop
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28
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Bou Jawde S, Walkey AJ, Majumdar A, O'Connor GT, Smith BJ, Bates JHT, Lutchen KR, Suki B. Tracking respiratory mechanics around natural breathing rates via variable ventilation. Sci Rep 2020; 10:6722. [PMID: 32317734 PMCID: PMC7174375 DOI: 10.1038/s41598-020-63663-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 03/26/2020] [Indexed: 11/08/2022] Open
Abstract
Measuring respiratory resistance and elastance as a function of time, tidal volume, respiratory rate, and positive end-expiratory pressure can guide mechanical ventilation. However, current measurement techniques are limited since they are assessed intermittently at non-physiological frequencies or involve specialized equipment. To this end, we introduce ZVV, a practical approach to continuously track resistance and elastance during Variable Ventilation (VV), in which frequency and tidal volume vary from breath-to-breath. ZVV segments airway pressure and flow recordings into individual breaths, calculates resistance and elastance for each breath, bins them according to frequency or tidal volume and plots the results against bin means. ZVV's feasibility was assessed clinically in five human patients with acute lung injury, experimentally in five mice ventilated before and after lavage injury, and computationally using a viscoelastic respiratory model. ZVV provided continuous measurements in both settings, while the computational study revealed <2% estimation errors. Our findings support ZVV as a feasible technique to assess respiratory mechanics under physiological conditions. Additionally, in humans, ZVV detected a decrease in resistance and elastance with time by 12.8% and 6.2%, respectively, suggesting that VV can improve lung recruitment in some patients and can therefore potentially serve both as a dual diagnostic and therapeutic tool.
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Affiliation(s)
- Samer Bou Jawde
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
| | - Allan J Walkey
- Department of Medicine, Pulmonary, Allergy, Sleep, & Critical Care Medicine, Boston University, Boston, MA, USA
| | - Arnab Majumdar
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
| | - George T O'Connor
- Department of Medicine, Pulmonary, Allergy, Sleep, & Critical Care Medicine, Boston University, Boston, MA, USA
| | - Bradford J Smith
- Department of Bioengineering, University of Colorado Denver | Anschutz Medical Campus, Aurora, CO, USA
| | - Jason H T Bates
- Pulmonary/Critical Care Division, University of Vermont, Burlington, VT, USA
| | - Kenneth R Lutchen
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
| | - Béla Suki
- Department of Biomedical Engineering, Boston University, Boston, MA, USA.
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29
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Szczepan S, Michalik K, Borkowski J, Zatoń K. Effects of Swimming with Added Respiratory Dead Space on Cardiorespiratory Fitness and Lipid Metabolism. J Sports Sci Med 2020; 19:95-101. [PMID: 32132832 PMCID: PMC7039034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 12/03/2019] [Indexed: 06/10/2023]
Abstract
The aim of this study was to investigate the circulatory, respiratory, and metabolic effects of induced hypercapnia via added respiratory dead space (ARDS) during moderate-intensity swimming in recreational swimmers. A mixed-sex sample of 22 individuals was divided into homogeneous experimental (E) and control (C) groups controlled for maximal oxygen uptake (VO2max). The intervention involved 50 min of front crawl swimming performed at 60% VO2max twice weekly for 6 consecutive weeks. ARDS was induced via tube breathing (1000 ml) in group E. An incremental exercise test was administered pre- and post-intervention to assess cardiorespiratory fitness (CRF) by measuring VO2max, carbon dioxide volume, respiratory minute ventilation, respiratory exchange ratio (RER), and heart rate at 50, 100, 150, 200 W and at maximal workload. Body mass index (BMI), fat mass (FM), and fat-free mass (FFM) were also measured. The mean difference in glycerol concentration (ΔGLY) was assessed after the first and last swimming session. No significant between-group differences were observed at post-intervention. No within-group differences were observed at post-intervention except for RER which increased in group E at maximal workload. A 6-week swimming intervention with ARDS did not enhance CRF. The RER increase in group E is not indicative of a substrate shift towards increased lipid utilization. No change in ΔGLY is evident of a lack of enhanced triglyceride hydrolyzation that was also confirmed by similar pre- and post-intervention BMI, FM, and FMM.
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Affiliation(s)
- Stefan Szczepan
- Department of Swimming, University School of Physical Education in Wroclaw, Poland
| | - Kamil Michalik
- Department of Physiology and Biochemistry, University School of Physical Education in Wroclaw, Poland
| | - Jacek Borkowski
- Department of Physiology and Biochemistry, University School of Physical Education in Wroclaw, Poland
| | - Krystyna Zatoń
- Department of Swimming, University School of Physical Education in Wroclaw, Poland
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30
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Rodrigues LTC, Salata B, Horta-Júnior JDAC, Gargaglioni LH, Dias MB. Adenosine in the lateral hypothalamus/perifornical area does not participate on the CO 2 chemoreflex. Respir Physiol Neurobiol 2020; 276:103368. [PMID: 32061712 DOI: 10.1016/j.resp.2020.103368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/26/2019] [Accepted: 01/03/2020] [Indexed: 11/18/2022]
Abstract
The Lateral Hypothalamus/Perifornical Area (LH/PFA) has been shown to be involved with the hypercapnic ventilatory response, in a state-dependent manner. We have demonstrated that purinergic signaling through ATP in the LH/PFA has an excitatory effect in ventilatory response to CO2 in awake rats in the dark phase of the diurnal cycle, but it is unknown whether the ATP metabolite adenosine, acting in the LH/PFA, modulates the ventilatory responses to hypercapnia. Here, we studied the effects of the microdialysis of adenosine (A1/A2 adenosine receptors agonist; 17 mM) and an A1 receptor antagonist (DPCPX; 0.1 mM) into the LH/PFA of conscious rats on ventilation in room air and in 7% CO2 during the light and the dark phases of the diurnal cycle. The microdialysis of adenosine and DPCPX caused no change in the CO2 ventilatory responses of rats during wakefulness or NREM sleep in either the dark or light period. Our data suggest that adenosine in the LH/PFA does not contribute to the hypercapnic ventilatory response in conscious rats.
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Affiliation(s)
| | - Bruno Salata
- Department of Physiology, Institute of Biosciences, Sao Paulo State University-UNESP, Botucatu, SP, Brazil.
| | | | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, Sao Paulo State University-FCAV, Jaboticabal, SP, Brazil.
| | - Mirela Barros Dias
- Department of Physiology, Institute of Biosciences, Sao Paulo State University-UNESP, Botucatu, SP, Brazil.
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31
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Brat K, Chobola M, Homolka P, Heroutova M, Benej M, Mitas L, Olson LJ, Cundrle I. Poor ventilatory efficiency during exercise may predict prolonged air leak after pulmonary lobectomy. Interact Cardiovasc Thorac Surg 2020; 30:269-272. [PMID: 31630177 DOI: 10.1093/icvts/ivz255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/16/2019] [Accepted: 09/23/2019] [Indexed: 11/15/2022] Open
Abstract
Poor ventilatory efficiency, defined as the increase in minute ventilation relative to carbon dioxide production during exercise (VE/VCO2 slope), may be associated with dynamic hyperinflation and thereby promote the development of prolonged air leak (PAL) after lung resection. Consecutive lung lobectomy candidates (n = 96) were recruited for this prospective two-centre study. All subjects underwent pulmonary function tests and cardiopulmonary exercise testing prior to surgery. PAL was defined as the presence of air leaks from the chest tube on the 5th postoperative day and developed in 28 (29%) subjects. Subjects with PAL were not different in terms of age, sex, American Society of Anesthesiologists class, type of surgery (thoracotomy/video-assisted thoracoscopic surgery) and site of surgery (right/left lung; upper/lower lobes). Subjects with PAL had more frequent pleural adhesions (50% vs 21%; P = 0.006) and steeper VE/VCO2 slope (35 ± 7 vs 30 ± 5; P = 0.001). Stepwise logistic regression showed that only the presence of pleural adhesions [odds ratio (OR) 3.9, 95% confidence interval (CI) 1.4-10.9; P = 0.008] and VE/VCO2 slope (OR 1.1, 95% CI 1.0-1.2; P = 0.003) were independently associated with PAL (AUC 0.74, 95% CI 0.62-0.86). We conclude that a high VE/VCO2 slope during exercise may be helpful in identifying patients at greater risk for the development of PAL after lung lobectomy. CLINICAL TRIAL REGISTRATION NUMBER ClinicalTrials.gov identifier: NCT03498352.
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Affiliation(s)
- Kristian Brat
- Department of Respiratory Diseases, University Hospital Brno, Brno, Czech Republic
- Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Milos Chobola
- Faculty of Medicine, Masaryk University, Brno, Czech Republic
- Department of Anesthesiology and Intensive Care, St. Anne's University Hospital, Brno, Czech Republic
| | - Pavel Homolka
- Faculty of Medicine, Masaryk University, Brno, Czech Republic
- Department of Sports Medicine and Rehabilitation, St. Anne's University Hospital, Brno, Czech Republic
| | - Michaela Heroutova
- Department of Respiratory Diseases, University Hospital Brno, Brno, Czech Republic
| | - Michal Benej
- Faculty of Medicine, Masaryk University, Brno, Czech Republic
- First Department of Surgery, St. Anne's University Hospital, Brno, Czech Republic
| | - Ladislav Mitas
- Faculty of Medicine, Masaryk University, Brno, Czech Republic
- Department of Surgery, University Hospital Brno, Czech Republic
| | - Lyle J Olson
- Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Ivan Cundrle
- Faculty of Medicine, Masaryk University, Brno, Czech Republic
- Department of Anesthesiology and Intensive Care, St. Anne's University Hospital, Brno, Czech Republic
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Chen M, Doganay O, Matin T, McIntyre A, Rahman N, Bulte D, Gleeson F. Delayed ventilation assessment using fast dynamic hyperpolarised Xenon-129 magnetic resonance imaging. Eur Radiol 2020; 30:1145-1155. [PMID: 31485836 PMCID: PMC6957546 DOI: 10.1007/s00330-019-06415-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/09/2019] [Accepted: 08/07/2019] [Indexed: 12/18/2022]
Abstract
OBJECTIVES To investigate the use of a fast dynamic hyperpolarised 129Xe ventilation magnetic resonance imaging (DXeV-MRI) method for detecting and quantifying delayed ventilation in patients with chronic obstructive pulmonary disease (COPD). METHODS Three male participants (age range 31-43) with healthy lungs and 15 patients (M/F = 12:3, age range = 48-73) with COPD (stages II-IV) underwent spirometry tests, quantitative chest computed tomography (QCT), and DXeV-MRI at 1.5-Tesla. Regional delayed ventilation was captured by measuring the temporal signal change in each lung region of interest (ROI) in comparison to that in the trachea. In addition to its qualitative assessment through visual inspection by a clinical radiologist, delayed ventilation was quantitatively captured by calculating a covariance measurement of the lung ROI and trachea signals, and quantified using both the time delay, and the difference between the integrated areas covered by the signal-time curves of the two signals. RESULTS Regional temporal ventilation, consistent with the expected physiological changes across a free breathing cycle, was demonstrated with DXeV-MRI in all patients. Delayed ventilation was observed in 13 of the 15 COPD patients and involved variable lung ROIs. This was in contrast to the control group, where no delayed ventilation was demonstrated (p = 0.0173). CONCLUSIONS DXeV-MRI offers a non-invasive way of detecting and quantifying delayed ventilation in patients with COPD, and provides physiological information on regional pulmonary function during a full breathing cycle. KEY POINTS • Dynamic xenon MRI allows for the non-invasive detection and measurement of delayed ventilation in COPD patients. • Dynamic xenon MRI during a free breathing cycle can provide unique information about pulmonary physiology and pulmonary disease pathophysiology. • With further validation, dynamic xenon MRI could offer a non-invasive way of measuring collateral ventilation which can then be used to guide lung volume reduction therapy (LVRT) for certain COPD patients.
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Affiliation(s)
- Mitchell Chen
- The Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Old Road, Oxford, OX3 7LE, UK.
| | - Ozkan Doganay
- The Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Old Road, Oxford, OX3 7LE, UK
- Department of Oncology, Oxford University, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
| | - Tahreema Matin
- The Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Old Road, Oxford, OX3 7LE, UK
| | - Anthony McIntyre
- The Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Old Road, Oxford, OX3 7LE, UK
| | - Najib Rahman
- The Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Old Road, Oxford, OX3 7LE, UK
- Oxford NIHR Biomedical Research Centre, The Churchill Hospital, Old Road, Oxford, OX3 7LE, UK
| | - Daniel Bulte
- The Institute of Biomedical Engineering, Oxford University, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
| | - Fergus Gleeson
- The Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Old Road, Oxford, OX3 7LE, UK
- Department of Oncology, Oxford University, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
- Oxford NIHR Biomedical Research Centre, The Churchill Hospital, Old Road, Oxford, OX3 7LE, UK
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Garner DP, Lamira J. Respiratory outcomes with the use of a lower custom fit genioglossal-effecting oral appliance. Clin Exp Dent Res 2020; 6:100-106. [PMID: 32067401 PMCID: PMC7025983 DOI: 10.1002/cre2.254] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 09/05/2019] [Accepted: 09/10/2019] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVE Sleep apnea research cites that an oral appliance, which places the mandible in a more forward position and the genioglossus (tongue muscle) on the floor of the mouth, improves aspects of the pharyngeal opening. Exercise science research has cited improvements in airway dynamics and physiological variables with oral appliance use during exercise. Thus, the purpose of this study was to design an oral appliance that would act on the genioglossus and determine if there were effects on respiratory parameters while exercising. MATERIALS AND METHODS Seventeen healthy subjects ages 18-43 participated in this study. Prior to the exercise protocol, the order of the oral applicance (OA) or no oral appliance (no OA) condition was randomly assigned to subjects, with subjects completing both conditions. Respiratory parameters (respiratory rate, ventilation, oxygen, and carbon dioxide) were measured between conditions while subjects ran for 10 min at steady state. RESULTS The results demonstrated that both respiratory rate (25.97 BPM, OA and 28.35 BPM, no OA) and ventilation (47.66 l/min, OA and 50.34 l/min, No OA) were significantly lowered (p < .01) in the OA condition. There were no differences in carbon dioxide (1.89 l/min, no OA and 1.88 l/min, OA) or oxygen outcomes (2.17 l/min, no OA and 2.17 l/min OA). DISCUSSION The outcomes from this study suggest that the design of the oral appliance elicits an effect on the genioglossus, thereby resulting in lowered respiratory rate and ventilation with no negative effects on oxygen uptake during exercise.
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Affiliation(s)
- Dena P. Garner
- Department of Health and Human Performance, the CitadelThe CitadelCharlestonSouth Carolina
| | - Jensine Lamira
- Department of Health and Human Performance, the CitadelThe CitadelCharlestonSouth Carolina
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Sakuna M, Mekhora K, Jalajondeja W, Jalajondeja C. Breathing retraining with chest wall mobilization improves respiratory reserve and decreases hyperactivity of accessory breathing muscles during respiratory excursions: A randomized controlled trial. Acta Bioeng Biomech 2020; 22:153-159. [PMID: 33518729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
PURPOSE The aim of this paper was to evaluate the effects of breathing retraining with chest wall mobilization on the onset of accessory breathing muscle recruitment and respiratory reserve in individuals with chronic neck pain. METHODS Thirty-two participants with non-specific chronic neck pain were randomly assigned into intervention and control groups. The intervention group received 30 minutes of breathing retraining with chest wall mobilization and the control group was assigned to rest for 30 minutes. Electromyography (EMG) of upper trapezius (UT), scalene (SC), and sternocleidomastoid (SCM) muscles were recorded during respiratory excursions by cycling for 12 minutes. Measurement of maximum voluntary ventilation (MVV), chest expansion, and pain intensity were taken during normal breathing. The immediate effects within each group and between two groups were analyzed. RESULTS Significant improvement in respiratory reserve was observed in the intervention group compared to control group through prolonged EMG onset of accessory breathing muscles. Moreover, increase of MVV, chest expansion and decrease in pain intensity were observed. CONCLUSIONS This research suggests that breathing patterns and chest expansion should be considered within the physical assessment of breathing retraining, and that chest wall mobilization offers clinically important improvements in patients with chronic neck pain.
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Affiliation(s)
- Monticha Sakuna
- Faculty of Physical Therapy, Mahidol University, Nakhon Pathom, Thailand
| | - Keerin Mekhora
- Faculty of Physical Therapy, Mahidol University, Nakhon Pathom, Thailand
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Tyfa Z, JÓŹwik P, Obidowski D, Reorowicz P, Jodko D, Kapka K, Makosiej R, Czkwianianc E, JÓŹwik K. Inhaled drug airflow patterns and particles deposition in the paediatric respiratory tract. Acta Bioeng Biomech 2020; 22:101-110. [PMID: 32868947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
PURPOSE The effectiveness of inhaled drugs is strictly related to areas reachable by drug particles. Unless particles reach the desired part of the bronchial tree, their influence might not meet the expectations. Consequently, the disease progress might not be stopped or even slowed down. Therefore, the primary objective of this research was to analyze the airflow patterns and particle deposition of a standard inhaled drug using computational fluid dynamics. METHODS The study was devoted to the analysis of the particle diameter influence on their deposition areas within the entire respiratory tract. Two patient-specific respiratory tract models, for 6 and 12-year-old patients, were reconstructed based on the computed tomography examinations. Numerical analyses were carried out as stationary ones with the constant inflow of the particles of various diameters (within the range of 1-50 μm). It was proven that depending on the particle size, their deposition within the respiratory tract varies significantly. RESULTS The vast majority of the particles with diameters over 20 μm is gathered on the walls of the throat, whereas particles of diameters 5-15 μm are accumulated mainly on the trachea walls, leaving the alveoli insufficiently supplied with the drug particles. CONCLUSIONS The inhaled drug size cannot be treated as negligible factor during the drug spraying. An improper distribution of the particles might not inhibit the symptoms of the asthma. Numerical simulations may improve drugs selection and visualize their distribution along the airways, which might accelerate asthma treatment personalization.
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Affiliation(s)
- Zbigniew Tyfa
- Institute of Turbomachinery, Lodz University of Technology, Łódź, Poland
| | - Paulina JÓŹwik
- Institute of Turbomachinery, Lodz University of Technology, Łódź, Poland
| | - Damian Obidowski
- Institute of Turbomachinery, Lodz University of Technology, Łódź, Poland
| | - Piotr Reorowicz
- Institute of Turbomachinery, Lodz University of Technology, Łódź, Poland
| | - Daniel Jodko
- Institute of Turbomachinery, Lodz University of Technology, Łódź, Poland
| | - Karolina Kapka
- Department of Gastroenterology, Allergology and Pediatrics, Polish Mother's Memorial Hospital Research Institute, Łódź, Poland
| | - Ryszard Makosiej
- Department of Gastroenterology, Allergology and Pediatrics, Polish Mother's Memorial Hospital Research Institute, Łódź, Poland
| | - ElŻbieta Czkwianianc
- Department of Gastroenterology, Allergology and Pediatrics, Polish Mother's Memorial Hospital Research Institute, Łódź, Poland
| | - Krzysztof JÓŹwik
- Institute of Turbomachinery, Lodz University of Technology, Łódź, Poland
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Schellart NA. Reduction of peak expiratory flow after a 5-meter dive with extreme exertion. Undersea Hyperb Med 2020; 47:461-466. [PMID: 32931673 DOI: 10.22462/03.07.2020.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The effects of physically exerting scuba dives on the airways are expected to affect the respiratory system and therefore the spirometric flow indices directly after surfacing. After on-air open-sea dives, the flow indices were examined with standard spirometry (maximal forced expiration) within 10 minutes pre- and post-dive. Twenty volunteers, age 49 ± 14 years (m ± SD) equipped with a dive computer to record the dive profile, cylinder pressures and water temperature (27°C), as well as a heart rate monitor, performed 5-meter dives of 27 minutes at maximal swimming velocity (v). Mean pulmonary ventilation (PV) was 48 ± 10 ambient L/minute (aL.min-1). Mean v was 34 ± 6 meters/minute and mean heart rate 143 beats per minute, about 80% of the on-land theoretical maximum. None of the flow variables changed except a decrease of 7.1% ± 8.3 (p=0.001) of the peak expiratory flow (PEF), pre-dive of 11.2 ± 2.7 L/minute. A likely major cause of the reduction of PEF is expiratory muscle fatigue. A small contribution of subclinical pulmonary edema cannot be excluded. The inhalation of dry air and the cooling of the airways are expected to affect PEF minimally. Although the change is normally clinically irrelevant, during emergency it may be of importance.
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Affiliation(s)
- Nico Am Schellart
- Amsterdam UMC, University of Amsterdam, Biomedical Engineering and Physics, Amsterdam, The Netherlands
- Foundation for Dive Research (SDR), Aerdenhout, The Netherlands
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Schöneich S, Hedwig B. Feedforward discharges couple the singing central pattern generator and ventilation central pattern generator in the cricket abdominal central nervous system. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2019; 205:881-895. [PMID: 31691096 PMCID: PMC6863954 DOI: 10.1007/s00359-019-01377-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/19/2019] [Accepted: 10/24/2019] [Indexed: 12/28/2022]
Abstract
We investigated the central nervous coordination between singing motor activity and abdominal ventilatory pumping in crickets. Fictive singing, with sensory feedback removed, was elicited by eserine-microinjection into the brain, and the motor activity underlying singing and abdominal ventilation was recorded with extracellular electrodes. During singing, expiratory abdominal muscle activity is tightly phase coupled to the chirping pattern. Occasional temporary desynchronization of the two motor patterns indicate discrete central pattern generator (CPG) networks that can operate independently. Intracellular recordings revealed a sub-threshold depolarization in phase with the ventilatory cycle in a singing-CPG interneuron, and in a ventilation-CPG interneuron an excitatory input in phase with each syllable of the chirps. Inhibitory synaptic inputs coupled to the syllables of the singing motor pattern were present in another ventilatory interneuron, which is not part of the ventilation-CPG. Our recordings suggest that the two centrally generated motor patterns are coordinated by reciprocal feedforward discharges from the singing-CPG to the ventilation-CPG and vice versa. Consequently, expiratory contraction of the abdomen usually occurs in phase with the chirps and ventilation accelerates during singing due to entrainment by the faster chirp cycle.
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Affiliation(s)
- Stefan Schöneich
- Department of Zoology, University of Cambridge, Cambridge, UK
- Institute of Zoology and Evolutionary Research, Friedrich-Schiller-University Jena, Jena, Germany
| | - Berthold Hedwig
- Department of Zoology, University of Cambridge, Cambridge, UK.
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Song B, Li Y, Sun J, Qi Y, Li P, Li Y, Gu Z. Computational fluid dynamics simulation of changes in the morphology and airflow dynamics of the upper airways in OSAHS patients after treatment with oral appliances. PLoS One 2019; 14:e0219642. [PMID: 31721777 PMCID: PMC6853319 DOI: 10.1371/journal.pone.0219642] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 10/23/2019] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVES To explore the changes of morphology and internal airflow in upper airways (UA) after the use of oral appliances (OAs) in patients with obstructive sleep apnea hypopnea syndrome (OSAHS), and investigate the mechanisms by which OAs function as a therapy for OSAHS. METHODS Eight OSAHS patients (all male, aged 37-58, mean age 46.25) underwent CT scans before and after OA use. Then, computational fluid dynamics(CFD) models were built on the base of the CT scans using Mimics and ANSYS ICEM CFD software. The internal airflow of the upper airways was simulated using ANSYS-FLUENT and the results were analyzed using ANSYS-CFD-Post. The data were analyzed to identify the most important changes of biomechanical properties between patients with and without OA intervention. Upper airway morphology and the internal airflow changes were compared using t-tests and Spearman correlation coefficient analysis. RESULTS The narrowest area of upper airways was found to be located in the lower bound of velopharynx, where the volume and pressure were statistically significantly increased (P<0.05) and the air velocity was statistically significantly decreased (P<0.05) in the presence of the OA(P<0.05). After wearing OA, pharyngeal resistance was significantly decreased (P<0.05), from 290.63 to 186.25Pa/L, and the airflow resistance of the pharynx has reduced by 35.9%. CONCLUSION The enlargement of the upper airway after wearing the OA changed its airflow dynamics, which decreased the negative pressure and resistance in narrow areas of the upper airways. Thus, the collapsibility of the upper airways was reduced and patency was sustained.
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Affiliation(s)
- Baolong Song
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi’an, P.R. China
| | - Yibo Li
- Department of Orthodontics, Changsha Stomatological Hospital, Changsha, Hunan, P.R. China
| | - Jianwei Sun
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi’an, P.R. China
| | - Yizhe Qi
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi’an, P.R. China
| | - Peng Li
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi’an, P.R. China
| | - Yongming Li
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi’an, P.R. China
- * E-mail: (LY); (GZ)
| | - Zexu Gu
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi’an, P.R. China
- * E-mail: (LY); (GZ)
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Panza GS, Herrick JE, Chin LM, Gollie JM, Collins JP, O’Connell DG, Guccione AA. Effect of overground locomotor training on ventilatory kinetics and rate of perceived exertion in persons with cervical motor-incomplete spinal cord injury. Spinal Cord Ser Cases 2019; 5:80. [PMID: 31632738 PMCID: PMC6786384 DOI: 10.1038/s41394-019-0223-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/29/2019] [Accepted: 09/08/2019] [Indexed: 11/09/2022] Open
Abstract
Study design Pre-post, pilot study. Objectives To characterize ventilatory (VE) responses to exercise following warm-up walking in individuals with chronic incomplete spinal cord injury (iSCI) during constant work rate (CWR) exercise. Secondarily, to investigate VE and tidal volume (VT) variability, and ratings of perceived exertion (RPE) before and after overground locomotor training (OLT). Setting Research laboratory. Methods A 6-min CWR walking bout at preferred pace was used as a warm-up followed by 6 min of rest and a second 6-min CWR bout at above preferred walking pace. The second CWR bout was analyzed. Breath-by-breath ventilatory data were examined using a curvilinear least squares fitting procedure with a mono-exponential model. VE and VT variability was calculated as the difference between the observed and predicted values and RPE was taken every 2 min. Results Participants (n = 3, C4-C5) achieved a hyperpneic response to exercise in VE and VT. OLT resulted in faster ventilatory kinetics and reductions of 24 and 29% for VE and VT variability, respectively. A 30% reduction in RPE was concurrent with the reductions in ventilatory variability. Conclusions OLT may improve ventilatory control during CWR in patients with cervical motor-iSCI. These data suggest that in some participants with iSCI, ventilation may influence RPE during walking. Future research should investigate mechanisms of ventilatory variability and its implications in walking performance in patients with iSCI.
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Affiliation(s)
- Gino S. Panza
- John D. Dingell Veterans Affairs Medical Center, Detroit, MI USA
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI USA
| | - Jeffrey E. Herrick
- Department of Exercise Physiology, University of Lynchburg, Lynchburg, VA USA
| | - Lisa M. Chin
- Rehabilitation Medicine Department, National Institutes of Health, Clinical Center, Bethesda, MD USA
| | | | | | | | - Andrew A. Guccione
- Department of Rehabilitation Science, George Mason University, Fairfax, VA USA
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Kaneda S, Iida M, Yamamoto H, Sekine M, Ebisumoto K, Sakai A, Takakura Y. Evaluation of Nasal Airflow and Resistance: Computational Modeling for Experimental Measurements. Tokai J Exp Clin Med 2019; 44:59-67. [PMID: 31448398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 06/26/2019] [Indexed: 06/10/2023]
Abstract
OBJECTIVE When evaluating nasal obstruction, conventional measurements of nasal patency do not necessarily correspond to a patient's subjective symptoms. The aim of this research is to seek an objective evaluation method by establishing computational modeling for nasal patency measurements. METHODS We created a computer-generated geometrical model of the nasal cavity from computed-tomography scans of an adult male, presented a computational modeling method for evaluating the nasal patency in the deep-breathing state, and simulated numerically the airflow within the nasal cavity in the natural- and deep-breathing states. RESULTS During inhalation in the natural-breathing state, the airflow was higher in the center of the nasal cavity and lower in the upper and lower portions, with the airflow characteristics being associated with the nasal functions. In the deep-breathing state, the computed nasal patency was compared with that measured experimentally by rhinomanometry. The quantitative accordance between computation and experiment was unsatisfactory, but the qualitative tendencies were similar. CONCLUSION Through natural- and deep-breathing computations, the roles and functions of the olfactory region, nasal valve, and middle and inferior meatuses were evaluated from the flow patterns and pressure, with correlation to the nasal resistance and physiology. Above all, from the deep-breathing computation using the present computational modeling, it was deduced that the pressure difference is essential for determining the nasal sites at which the nasal resistance was produced. Thus, numerical simulation with computational modeling is potentially an objective method for evaluating nasal obstruction.
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Affiliation(s)
- Shoji Kaneda
- Department of Otolaryngology, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan.
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Soni B, Nayak AK. Effect of inspiration cycle and ventilation rate on heat exchange in human respiratory airways. J Therm Biol 2019; 84:357-367. [PMID: 31466774 DOI: 10.1016/j.jtherbio.2019.07.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 06/09/2019] [Accepted: 07/25/2019] [Indexed: 11/18/2022]
Abstract
A transient three dimensional (3D) theoretical axisymmetric model is developed for heat exchange across the human respiratory tract during inspiration phase and applied to study the changes in the airway temperature and velocity profile for varying ventilation rates and inhalation temperatures. A multi-compartment approach is used to study the same to avoid the airway scaling problem from micro to nano scale. This analysis also includes the role of water evaporation in mucus and non perfused tissue layers and the role of capillary bed in thermal variations during respiration. The results of heat transfer in airway and mucus layer depend on the local morphological parameters. The results are compared with the case of hypothetical regular geometry to show the significance of local morphology. The location where the inhaled air gets saturated with the body core temperature is computed to estimate the saturation distance of air. The complete analysis is made for two breathing cycles with different inhalation to exhalation ratios. The results indicate that decreasing the ventilation rate and increasing the respiration cycle can avoid the deep penetration of heat into the tract and consequently tissue thermal injury can be avoided. We have also explained numerically the role of mucus layer in avoiding tissue injury in intra-thoracic airways. We have also observed a significant difference in results for high ventilation rates between the cases of actual (cast replica) and regular airway geometry. The numerical results are in good adjustment with existing experimental data and thus validate our approach.
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Affiliation(s)
- Bharat Soni
- Department of Mathematics, Indian Institute of Technology Roorkee, Roorkee, India.
| | - Ameeya Kumar Nayak
- Department of Mathematics, Indian Institute of Technology Roorkee, Roorkee, India.
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Yunis A, Doros G, Luptak I, Connors LH, Sam F. Use of Ventilatory Efficiency Slope as a Marker for Increased Mortality in Wild-Type Transthyretin Cardiac Amyloidosis. Am J Cardiol 2019; 124:122-130. [PMID: 31053293 DOI: 10.1016/j.amjcard.2019.03.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 03/13/2019] [Accepted: 03/19/2019] [Indexed: 01/21/2023]
Abstract
Wild-type transthyretin amyloidosis (ATTRwt) results in an infiltrative cardiomyopathy often culminating in symptomatic heart failure. The use of cardiopulmonary exercise testing (CPET) in determining outcomes in ATTRwt cardiac amyloidosis is unknown. Given the emergence of novel therapies to treat transthyretin amyloidosis, we sought to investigate the utility of CPET on outcomes in patients with ATTRwt cardiomyopathy. Fifty-six patients, with biopsy and immunohistochemically proved ATTRwt, were enrolled between 2005 and 2015, as part of an NIH ATTRwt substudy at the Boston University Amyloidosis Center. Patients were prospectively studied, which included laboratory tests, electrocardiogram, echocardiography, in addition to CPET. In this cohort of ATTRwt patients who performed CPET were elderly, all were male, and predominantly white (69.9%). The overall median survival was 59.01 months (95% confidence interval [CI] 49.29 to 88.69). By multivariate analysis, C-reactive protein (CRP; hazard ratio [HR] 1.10 [1.03 to 1.18]), decreased sodium (HR 0.75 [0.58 to 0.97]), creatinine (HR 7.48 [2.44 to 22.98]) and VE/VCO2 (HR 1.10 [1.05 to 1.16]) were significant risk factors for mortality (p <0.05). Peak VO2 was insignificant by both univariate and multivariate analyses. ATTRwt patients with VE/VCO2 >40 had a worse median survival of 38.54 months (95% CI 32.63 to 51.47) versus 88.69 months (95% CI 56.26 to 89.49) than patients with VE/VCO2 slope ≤40. Receiver-operating characteristic curve showed that the combination of VE/VCO2, CRP, sodium, and creatinine (Area under the ROC Curve [AUC], 0.89) predicted 1-year mortality in ATTRwt cardiac amyloidosis. In conclusion, increased VE/VCO2, in combination with CRP, sodium, and creatinine, may identify patients at increased risk of death in ATTRwt cardiomyopathy. VE/VCO2 might have a role in objectively assessing therapeutic response in ATTRwt cardiac amyloidosis.
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Affiliation(s)
- Adil Yunis
- Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts
| | - Gheorge Doros
- Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts
| | - Ivan Luptak
- Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts; Cardiovascular Section, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts; Evans Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts
| | - Lawreen H Connors
- Alan and Sandra Gerry Amyloid Research Laboratory in the Amyloidosis Center, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts
| | - Flora Sam
- Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts; Cardiovascular Section, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts; Evans Department of Medicine, Boston University School of Medicine, Boston Medical Center, Boston, Massachusetts.
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Klimeš F, Voskrebenzev A, Gutberlet M, Kern A, Behrendt L, Kaireit TF, Czerner C, Renne J, Wacker F, Vogel-Claussen J. Free-breathing quantification of regional ventilation derived by phase-resolved functional lung (PREFUL) MRI. NMR Biomed 2019; 32:e4088. [PMID: 30908743 DOI: 10.1002/nbm.4088] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 02/11/2019] [Accepted: 02/12/2019] [Indexed: 06/09/2023]
Abstract
PURPOSE To test the feasibility of regional fully quantitative ventilation measurement in free breathing derived by phase-resolved functional lung (PREFUL) MRI in the supine and prone positions. In addition, the influence of T2 * relaxation time on ventilation quantification is assessed. METHODS Twelve healthy volunteers underwent functional MRI at 1.5 T using a 2D triple-echo spoiled gradient echo sequence allowing for quantitative measurement of T2 * relaxation time. Minute ventilation (ΔV) was quantified by conventional fractional ventilation (FV) and the newly introduced regional ventilation (VR), which corrects volume errors due to image registration. ΔVFV versus ΔVVR and ΔVVR versus ΔVVR with T2 * correction were compared using Bland-Altman plots and correlation analysis. The repeatability and physiological plausibility of all measurements were tested in the supine and prone positions. RESULTS On global and regional scales a strong correlation was observed between ΔVFV versus ΔVVR and ΔVVR versus ΔVVRT2* (r > 0.93); however, regional Bland-Altman analysis showed systematic differences (p < 0.0001). Unlike ΔVVRT2* , ΔVVR and ΔVFV showed expected physiologic anterior-posterior gradients, which decreased in the supine but not in the prone position at second measurement during 3 min in the same position. For all quantification methods a moderate repeatability (coefficient of variation <20%) of ventilation was found. CONCLUSION A fully quantified regional ventilation measurement using ΔVVR in free breathing is feasible and shows physiologically plausible results. In contrast to conventional ΔVFV, volume errors due to image registration are eliminated with the ΔVVR approach. However, correction for the T2 * effect remains challenging.
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Affiliation(s)
- F Klimeš
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - A Voskrebenzev
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - M Gutberlet
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - A Kern
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - L Behrendt
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - T F Kaireit
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - C Czerner
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - J Renne
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - F Wacker
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
| | - J Vogel-Claussen
- Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research, Hanover, Germany
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Bluth T, Kiss T, Kircher M, Braune A, Bozsak C, Huhle R, Scharffenberg M, Herzog M, Roegner J, Herzog P, Vivona L, Millone M, Dössel O, Andreeff M, Koch T, Kotzerke J, Stender B, Gama de Abreu M. Measurement of relative lung perfusion with electrical impedance and positron emission tomography: an experimental comparative study in pigs. Br J Anaesth 2019; 123:246-254. [PMID: 31160064 DOI: 10.1016/j.bja.2019.04.056] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 04/08/2019] [Accepted: 04/09/2019] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Electrical impedance tomography (EIT) with indicator dilution may be clinically useful to measure relative lung perfusion, but there is limited information on the performance of this technique. METHODS Thirteen pigs (50-66 kg) were anaesthetised and mechanically ventilated. Sequential changes in ventilation were made: (i) right-lung ventilation with left-lung collapse, (ii) two-lung ventilation with optimised PEEP, (iii) two-lung ventilation with zero PEEP after saline lung lavage, (iv) two-lung ventilation with maximum PEEP (20/25 cm H2O to achieve peak airway pressure 45 cm H2O), and (v) two-lung ventilation under unilateral pulmonary artery occlusion. Relative lung perfusion was assessed with EIT and central venous injection of saline 3%, 5%, and 10% (10 ml) during breath holds. Relative perfusion was determined by positron emission tomography (PET) using 68Gallium-labelled microspheres. EIT and PET were compared in eight regions of equal ventro-dorsal height (right, left, ventral, mid-ventral, mid-dorsal, and dorsal), and directional changes in regional perfusion were determined. RESULTS Differences between methods were relatively small (95% of values differed by less than 8.7%, 8.9%, and 9.5% for saline 10%, 5%, and 3%, respectively). Compared with PET, EIT underestimated relative perfusion in dependent, and overestimated it in non-dependent, regions. EIT and PET detected the same direction of change in relative lung perfusion in 68.9-95.9% of measurements. CONCLUSIONS The agreement between EIT and PET for measuring and tracking changes of relative lung perfusion was satisfactory for clinical purposes. Indicator-based EIT may prove useful for measuring pulmonary perfusion at bedside.
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Affiliation(s)
- T Bluth
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - T Kiss
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - M Kircher
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - A Braune
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - C Bozsak
- Drägerwerk AG & Co. KGaA, Lübeck, Germany
| | - R Huhle
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - M Scharffenberg
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - M Herzog
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - J Roegner
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - P Herzog
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - L Vivona
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; Department of Neurosciences, Reproductive and Odontostomatological Sciences, University of Naples Federico II, Naples, Italy
| | - M Millone
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; IRCCS AOU San Martino IST, Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy
| | - O Dössel
- Institute of Biomedical Engineering, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - M Andreeff
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Dresden, Germany
| | - T Koch
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - J Kotzerke
- Department of Nuclear Medicine, University Hospital Carl Gustav Carus, Dresden, Germany
| | - B Stender
- Drägerwerk AG & Co. KGaA, Lübeck, Germany
| | - M Gama de Abreu
- Pulmonary Engineering Group Dresden, Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
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Convertino VA, Lye KR, Koons NJ, Joyner MJ. Physiological comparison of hemorrhagic shock and V˙ O 2max: A conceptual framework for defining the limitation of oxygen delivery. Exp Biol Med (Maywood) 2019; 244:690-701. [PMID: 31042073 PMCID: PMC6552402 DOI: 10.1177/1535370219846425] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
IMPACT STATEMENT Disturbance of normal homeostasis occurs when oxygen delivery and energy stores to the body's tissues fail to meet the energy requirement of cells. The work submitted in this review is important because it advances the understanding of inadequate oxygen delivery as it relates to early diagnosis and treatment of circulatory shock and its relationship to disturbance of normal functioning of cellular metabolism in life-threatening conditions of hemorrhage. We explored data from the clinical and exercise literature to construct for the first time a conceptual framework for defining the limitation of inadequate delivery of oxygen by comparing the physiology of hemorrhagic shock caused by severe blood loss to maximal oxygen uptake induced by intense physical exercise. We also provide a translational framework in which understanding the fundamental relationship between the body's reserve to compensate for conditions of inadequate oxygen delivery as a limiting factor to V ˙ O2max helps to re-evaluate paradigms of triage for improved monitoring of accurate resuscitation in patients suffering from hemorrhagic shock.
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Affiliation(s)
- Victor A Convertino
- Battlefield Health & Trauma Center for Human Integrative Physiology, U. S. Army Institute of Surgical Research, Fort Sam Houston, TX 78234, USA
| | - Kristen R Lye
- Battlefield Health & Trauma Center for Human Integrative Physiology, U. S. Army Institute of Surgical Research, Fort Sam Houston, TX 78234, USA
| | - Natalie J Koons
- Battlefield Health & Trauma Center for Human Integrative Physiology, U. S. Army Institute of Surgical Research, Fort Sam Houston, TX 78234, USA
| | - Michael J Joyner
- Department of Anesthesiology, Mayo Clinic, Rochester, MN 55905, USA
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Modena DAO, Moreira MM, Paschoal IA, Pereira MC, Martins LC, Cazzo E, Chaim EA. Respiratory evaluation through volumetric capnography among grade III obese and eutrophic individuals: a comparative study. SAO PAULO MED J 2019; 137:177-183. [PMID: 29340500 PMCID: PMC9721226 DOI: 10.1590/1516-3180.2017.0085011017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 10/01/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Excess trunk body fat in obese individuals influences respiratory physiological function. The aims of this study were to compare volumetric capnography findings (VCap) between severely obese patients and normal-weight subjects and to assess whether there is any association between neck circumference (NC), waist-hip ratio (WHR) and VCap among grade III obese individuals. DESIGN AND SETTING Analytical observational case-matched cross-sectional study, University of Campinas. METHODS This cross-sectional study compared VCap variables between 60 stage III obese patients and 60 normal-weight individuals. RESULTS In comparison with the normal-weight group, obese patients presented higher alveolar minute volume (8.92 ± 4.94 versus 6.09 ± 2.2; P = < 0.0001), CO2 production (278 ± 91.0 versus 209 ± 60.23; P < 0.0001), expiratory tidal volume (807 ± 365 versus 624 ± 202; P = 0.005), CO2 production per breath (21.1 ± 9.7 versus 16.7 ± 6.16; P = 0.010) and peak expiratory flow (30.9 ± 11.9 versus 25.5 ± 9.13; P = 0.004). The end-expiratory CO2 (PetCO2) concentration (33.5 ± 4.88 versus 35.9 ± 3.79; P = 0.013) and the phase 3 slope were normalized according to expired tidal volume (0.02 ± 0.05 versus 0.03 ± 0.01; P = 0.049) were lower in the obese group. CONCLUSIONS The greater the NC was, the larger were the alveolar minute volume, anatomical dead space, CO2 production per minute and per breath and expiratory volume; whereas the smaller were the phase 2 slope (P2Slp), phase 3 slope (P3Slp) and pressure drop in the mouth during inspiration.
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Affiliation(s)
| | - Marcos Mello Moreira
- PT, PhD. Professor, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil.
| | - Ilma Aparecida Paschoal
- MD, PhD. Pneumologist and Professor, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil.
| | - Mônica Corso Pereira
- MD, PhD. Pneumologist and Professor, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil.
| | - Luiz Cláudio Martins
- MD, PhD. Pneumologist and Professor, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil.
| | - Everton Cazzo
- MD, PhD. Attending Physician and Assistant Lecturer, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil.
| | - Elinton Adami Chaim
- MD, PhD. General Surgeon and Professor, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil.
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Cornell K, Alam M, Lyden E, Wood L, LeVan TD, Nordgren TM, Bailey K, Hanson C. Saturated Fat Intake Is Associated with Lung Function in Individuals with Airflow Obstruction: Results from NHANES 2007⁻2012. Nutrients 2019; 11:nu11020317. [PMID: 30717299 PMCID: PMC6413158 DOI: 10.3390/nu11020317] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/28/2019] [Accepted: 01/29/2019] [Indexed: 01/14/2023] Open
Abstract
Nutritional status is a well-recognized prognostic indicator in chronic obstructive pulmonary disease (COPD); however, very little is known about the relationship between lung function and saturated fat intake. We used data from the cross-sectional National Health and Nutrition Examination Surveys (NHANES) to assess the relationship between saturated fatty acid (SFA) intake and lung function in the general US adult population. Adults in NHANES (2007⁻2012) with pre-bronchodilator spirometry measurements and dietary SFA intake were included. Primary outcomes were lung function including forced expiratory volume in one second (FEV₁), FEV₁, forced vital capacity (FVC), FEV₁/FVC ratio, percent predicted FEV₁ and percent predicted FVC. Multivariable regression models in the general population as well as those with spirometry-defined airflow obstruction were used to assess the relationship between lung function measurements and dietary SFA intake after adjustment for confounders. 11,180 eligible participants were included in this study. Univariate analysis revealed a statistically significant positive association between total SFA intake and lung function outcomes; however, these relationships were attenuated after adjustment for covariates. A secondary analysis of individuals with spirometry-defined airflow obstruction (FEV₁/FVC < 0.7) revealed that a lower intake of SFA was associated with reduced FEV1 (β = -126.4, p = 0.04 for quartile 1 vs. quartile 4), FVC (β = -165.8. p = 0.01 for quartile 1 vs. quartile 4), and percent predicted FVC (β = -3.3. p = 0.04 for quartile 1 vs. quartile 4), after adjustment for relevant confounders. No associations were observed for the FEV₁/FVC ratio and percent predicted FEV₁. It is possible that characteristics such as food source and fatty acid chain length may influence associations between saturated fatty acid intake and health outcomes.
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Affiliation(s)
- Kasey Cornell
- Internal Medicine Pulmonary, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Morshed Alam
- College of Public Health, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Elizabeth Lyden
- College of Public Health, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Lisa Wood
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle NSW 2308, Australia.
| | - Tricia D LeVan
- Internal Medicine Pulmonary, University of Nebraska Medical Center, Omaha, NE 68198, USA.
- College of Public Health Epidemiology, University of Nebraska, Omaha, NE 68198, USA.
- Research Service, VA Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA.
| | - Tara M Nordgren
- Division of Biomedical Sciences, University of California Riverside, Riverside, CA 92521, USA.
| | - Kristina Bailey
- Internal Medicine Pulmonary, University of Nebraska Medical Center, Omaha, NE 68198, USA.
| | - Corrine Hanson
- Medical Nutrition Education, College of Allied Health Professions, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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Pfitzner J, Fowlie JA, Kishore M, Michael AS, Lance DG. Arterial Oxygen Desaturation during only one of two Similar Thoracoscopic Procedures on the Same Patient. Anaesth Intensive Care 2019; 33:805-7. [PMID: 16398389 DOI: 10.1177/0310057x0503300617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The present report describes two similar thoracoscopic procedures performed on the same 81-year-old male patient. Because acute hypoxia had developed during one-lung ventilation on the first occasion, serial blood gases were taken during the second. Also, whereas on the first occasion the non-ventilated lung had been left open to air when one-lung ventilation was initiated, on the second it was connected to an ambient pressure oxygen source with the object of theoretically enabling apnoeic oxygenation during lung collapse. It is argued that this fundamental difference in anaesthetic practice may have contributed to the improved oxygenation that was recorded during the second thoracoscopy.
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Affiliation(s)
- J Pfitzner
- Department of Anaesthesia and Thoracic Surgery Unit, The Queen Elizabeth Hospital, Woodville, South Australia
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Busch SA, Bruce CD, Skow RJ, Pfoh JR, Day TA, Davenport MH, Steinback CD. Mechanisms of sympathetic regulation during Apnea. Physiol Rep 2019; 7:e13991. [PMID: 30693670 PMCID: PMC6349657 DOI: 10.14814/phy2.13991] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 12/26/2018] [Indexed: 12/11/2022] Open
Abstract
Volitional Apnea produces a robust peak sympathetic response through several interacting mechanisms. However, the specific contribution of each mechanism has not been elucidated. Muscle sympathetic activity was collected in participants (n = 10; 24 ± 3 years) that performed four maximal volitional apneas aimed at isolating lung-stretch (mechanical) and chemoreflex drive: (Ainslie and Duffin ) end-expiratory breath-hold, (Ainslie et al. ) end-inspiratory breath-hold, (Alpher et al. ) prehyperventilation breath-hold, and (Andersson and Schagatay ) prehyperoxia breath-hold. A final repeated rebreathe breath-hold protocol was performed to measure the peak sympathetic response during successive breath-holds at increasing chemoreflex stress. Finally, the influence of dynamic ventilation was assessed through asphyxic rebreathe. Muscle sympathetic activity was calculated as the change in burst frequency (burst/min), burst incidence (burst/100 heart-beats), and amplitude (au) between baseline and prevolitional breakpoint. Rebreathe was analyzed at similar chemoreflex stress as inspiratory breath-hold. All maneuvers increased muscle sympathetic activity compared to baseline (P < 0.01). However, prehyperoxia exhibited a smaller increase (+22.18 ± 9.13 burst/min; +25.52 ± 11.7 burst/100 heart-beats) compared to inspiratory, expiratory, and prehyperventilation breath-holds. At similar chemoreflex strain, rebreathe sympathetic activity was blunted compared to inspiratory breath-hold (P < 0.01). Finally, muscle sympathetic activity was not different between the repeated rebreathe trials, despite elevated chemoreflex stress and lower breath-hold duration with each subsequent breath-hold. We have demonstrated an obligatory role of the peripheral, but not central, chemoreflex (prehyperventilation vs. prehyperoxia) in producing peak sympathetic responses. At similar chemoreflex stresses the act of dynamic ventilation, but not static lung stretch per se, blunts muscle sympathetic activity. Finally, similar peak sympathetic responses during successive repeated breath-holds suggest a sympathetic ceiling may exist.
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Affiliation(s)
- Stephen A. Busch
- Neurovascular Health LaboratoryFaculty of Kinesiology, Sport, and RecreationUniversity of AlbertaEdmontonAlbertaCanada
| | - Christina D. Bruce
- Department of BiologyFaculty of Science and TechnologyMount Royal UniversityCalgaryAlbertaCanada
| | - Rachel J. Skow
- Neurovascular Health LaboratoryFaculty of Kinesiology, Sport, and RecreationUniversity of AlbertaEdmontonAlbertaCanada
| | - Jaime R. Pfoh
- Department of BiologyFaculty of Science and TechnologyMount Royal UniversityCalgaryAlbertaCanada
| | - Trevor A. Day
- Department of BiologyFaculty of Science and TechnologyMount Royal UniversityCalgaryAlbertaCanada
| | - Margie H. Davenport
- Neurovascular Health LaboratoryFaculty of Kinesiology, Sport, and RecreationUniversity of AlbertaEdmontonAlbertaCanada
| | - Craig D. Steinback
- Neurovascular Health LaboratoryFaculty of Kinesiology, Sport, and RecreationUniversity of AlbertaEdmontonAlbertaCanada
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Rex CE, Eckerström F, Heiberg J, Maagaard M, Rubak S, Redington A, Hjortdal VE. Surgical closure of a ventricular septal defect in early childhood leads to altered pulmonary function in adulthood: A long-term follow-up. Int J Cardiol 2019; 274:100-105. [PMID: 30001944 DOI: 10.1016/j.ijcard.2018.06.109] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/03/2018] [Accepted: 06/27/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND The long-term outlook after surgical closure of ventricular septal defect (VSD) has traditionally been considered benign. However, there is an increasing awareness of not only late cardiac dysfunction, but also pulmonary abnormalities. The primary aim of this study was to describe pulmonary function in adults with a surgically repaired VSD, and secondarily to determine the effects of salbutamol on the potential abnormalities. METHODS All patients (operated for a VSD in early childhood) and controls (age- and gender-matched) underwent static and dynamic spirometry, impulse oscillometry, multiple breath washout, diffusion capacity for carbon monoxide, and cardiopulmonary exercise testing. In a double-blinded, cross-over study, participants were randomized to inhalation of either 900 μg of salbutamol or placebo. The primary outcome was forced expiratory volume in 1 s. RESULTS In total, 30 participants with a surgically closed VSD and 30 healthy controls were included. The VSD participants had a lower forced expiratory volume in 1 s (99 ± 13% vs. 111 ± 13%), p < 0.001, impaired forced vital capacity, (106 ± 12% vs. 118 ± 13%), p < 0.001, and lower peak expiratory flow, (95 ± 18% vs. 118 ± 19%), p < 0.001, than the control group. Also, the VSD group had a lower alveolar volume than the control group, (92 ± 10% vs. 101 ± 11%), p < 0.001, but there were no differences in the remaining pulmonary function parameters. Salbutamol reduced airway resistances in both groups, but exercise performance was not improved by salbutamol, however. CONCLUSIONS Adults who have undergone surgical closure of a VSD in early childhood have reduced pulmonary function compared with controls, which is unaffected by inhalation of salbutamol.
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Affiliation(s)
- Christian E Rex
- Dept. of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Dept. of Clinical Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Filip Eckerström
- Dept. of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Dept. of Clinical Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Johan Heiberg
- Dept. of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Dept. of Clinical Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
| | - Marie Maagaard
- Dept. of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Dept. of Clinical Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | - Sune Rubak
- Dept. of Child and Adolescent Health, Danish Center of Pediatric Pulmonology and Allergology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Dept. of Clinical Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
| | | | - Vibeke E Hjortdal
- Dept. of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Dept. of Clinical Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark
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