scholarly journals Quantitative assessment of the airway response to bronchial tests based on a spirometric curve shift

2020 ◽  
Author(s):  
Adam Polak ◽  
Andrzej Obojski ◽  
Janusz Mroczka
Keyword(s):  
Bronchial Tree ◽  
Maximal Effect ◽  
Forced Expiration ◽  
Differential Measurement ◽  
Anatomy And Physiology ◽  
Function Test ◽  
Post Test ◽  
Airway Response ◽  
Conducting Airways ◽  
Curve Shift

<i>Objective:</i> Although spirometry is the most common pulmonary function test, there is no method to quantitatively infer about airway resistance or other properties from the flow-volume curves. Recently, an identifiable inverse model for forced expiration was proposed, as well as the idea to deduce changes in airway resistances and compliances from spirometric curve evolution. The aim of this work was to combine the above advances in a method for assessing the airway response to bronchial tests from a spirometric curve shift. <i>Methods:</i> The approach is based on the differential measurement of the degree, site of maximal effect and width of changes, further recalculated into relative changes in the distribution of airway resistances (<i>δR<sub>g</sub></i>) and compliances (<i>δC<sub>g</sub></i>) along the bronchial tree. To this end, appropriate models were identified using the pre- and post-test spirometry data. The accuracy was validated using sets of data simulated by the anatomy and physiology based models. Finally, the method was used to analyze the bronchodilation tests of three asthmatic subjects. <i>Results:</i> The expected errors in assessing the degree, site and width of changes in the zone of conducting airways were 6.3%, 2.4 generations and 22%, respectively, and for <i>δR<sub>g</sub></i> and <i>δC<sub>g</sub></i> were 5-10% and 13-16%, respectively. The analyses of clinical data indicated a significant reduction in resistances and an increase in compliances of airway generations 8-12, consistent with clinical knowledge. <i>Conclusion:</i> An unprecedented method to plausibly transforming the spirometry data into the site and degree of changes in airway properties has been proposed. <i>Significance:</i> The method can be used to deduce about the effects of bronchial tests, as well as to monitor changes in the airways between visits or to investigate how inhaled pharmaceuticals affect the bronchi.

Quantitative assessment of the airway response to bronchial tests based on a spirometric curve shift

2020 ◽  
Author(s):  
Adam Polak ◽  
Andrzej Obojski ◽  
Janusz Mroczka
Keyword(s):  
Bronchial Tree ◽  
Maximal Effect ◽  
Forced Expiration ◽  
Differential Measurement ◽  
Anatomy And Physiology ◽  
Function Test ◽  
Post Test ◽  
Airway Response ◽  
Conducting Airways ◽  
Curve Shift

<i>Objective:</i> Although spirometry is the most common pulmonary function test, there is no method to quantitatively infer about airway resistance or other properties from the flow-volume curves. Recently, an identifiable inverse model for forced expiration was proposed, as well as the idea to deduce changes in airway resistances and compliances from spirometric curve evolution. The aim of this work was to combine the above advances in a method for assessing the airway response to bronchial tests from a spirometric curve shift. <i>Methods:</i> The approach is based on the differential measurement of the degree, site of maximal effect and width of changes, further recalculated into relative changes in the distribution of airway resistances (<i>δR<sub>g</sub></i>) and compliances (<i>δC<sub>g</sub></i>) along the bronchial tree. To this end, appropriate models were identified using the pre- and post-test spirometry data. The accuracy was validated using sets of data simulated by the anatomy and physiology based models. Finally, the method was used to analyze the bronchodilation tests of three asthmatic subjects. <i>Results:</i> The expected errors in assessing the degree, site and width of changes in the zone of conducting airways were 6.3%, 2.4 generations and 22%, respectively, and for <i>δR<sub>g</sub></i> and <i>δC<sub>g</sub></i> were 5-10% and 13-16%, respectively. The analyses of clinical data indicated a significant reduction in resistances and an increase in compliances of airway generations 8-12, consistent with clinical knowledge. <i>Conclusion:</i> An unprecedented method to plausibly transforming the spirometry data into the site and degree of changes in airway properties has been proposed. <i>Significance:</i> The method can be used to deduce about the effects of bronchial tests, as well as to monitor changes in the airways between visits or to investigate how inhaled pharmaceuticals affect the bronchi.

Paradoxical conducting airway responses and heterogeneous regional ventilation after histamine inhalation in rabbit studied by synchrotron radiation CT

2009 ◽  
Vol 106 (6) ◽  
pp. 1949-1958 ◽  
Author(s):  
Sam Bayat ◽  
Liisa Porra ◽  
Heikki Suhonen ◽  
Pekka Suortti ◽  
Anssi R. A. Sovijärvi
Keyword(s):  
Synchrotron Radiation ◽  
Bronchial Tree ◽  
Regional Ventilation ◽  
Conducting Airway ◽  
Ventilation Heterogeneity ◽  
Airway Response ◽  
Poor Ventilation ◽  
Airway Responses ◽  
Conducting Airways

We studied both central conducting airway response and changes in the distribution of regional ventilation induced by inhaled histamine in healthy anesthetized and mechanically ventilated rabbit using a novel xenon-enhanced synchrotron radiation computed tomography (CT) imaging technique, K-edge subtraction imaging (KES). Images of specific ventilation were obtained using serial KES during xenon washin, in three axial lung slices, at baseline and twice after inhalation of histamine aerosol (50 or 125 mg/ml) in two groups of animals ( n = 6 each). Histamine inhalation caused large clustered areas of poor ventilation, characterized by a drop in average specific ventilation (sV̇m), but an increase in sV̇m in the remaining lung zones indicating ventilation redistribution. Ventilation heterogeneity, estimated as coefficient of variation (CV) of sV̇m significantly increased following histamine inhalation. The area of ventilation defects and CV were significantly larger with the higher histamine dose. In conducting airways, histamine inhalation caused a heterogeneous airway response combining narrowing and dilatation in individual airways of different generations, with the probability for constriction increasing peripherally. This finding provides further in vivo evidence that airway reactivity in response to inhaled histamine is complex and that airway response may vary substantially with location within the bronchial tree.

Methacholine-induced bronchoconstriction in dogs: effects of lung volume and O3 exposure

1988 ◽  
Vol 65 (6) ◽  
pp. 2679-2686 ◽  
Author(s):  
S. T. Kariya ◽  
S. A. Shore ◽  
W. A. Skornik ◽  
K. Anderson ◽  
R. H. Ingram ◽  
...  
Keyword(s):  
Lung Volume ◽  
Maximal Response ◽  
Maximal Effect ◽  
Response Curves ◽  
Lung Volumes ◽  
Before And After ◽  
Residual Capacity ◽  
Induced Changes ◽  
Conducting Airways ◽  
Concentration Response Curve

The maximal effect induced by methacholine (MCh) aerosols on pulmonary resistance (RL), and the effects of altering lung volume and O3 exposure on these induced changes in RL, was studied in five anesthetized and paralyzed dogs. RL was measured at functional residual capacity (FRC), and lung volumes above and below FRC, after exposure to MCh aerosols generated from solutions of 0.1-300 mg MCh/ml. The relative site of response was examined by magnifying parenchymal [RL with large tidal volume (VT) at fast frequency (RLLS)] or airway effects [RL with small VT at fast frequency (RLSF)]. Measurements were performed on dogs before and after 2 h of exposure to 3 ppm O3. MCh concentration-response curves for both RLLS and RLSF were sigmoid shaped. Alterations in mean lung volume did not alter RLLS; however, RLSF was larger below FRC than at higher lung volumes. Although O3 exposure resulted in small leftward shifts of the concentration-response curve for RLLS, the airway dominated index of RL (RLSF) was not altered by O3 exposure, nor was the maximal response using either index of RL. These data suggest O3 exposure does not affect MCh responses in conducting airways; rather, it affects responses of peripheral contractile elements to MCh, without changing their maximal response.

scholarly journals Teaching blind women about the anatomy and physiology of the female reproductive system through educational manual

2018 ◽  
Vol 18 (4) ◽  
pp. 755-761
Author(s):  
Mariana Gonçalves de Oliveira ◽  
Aline Cruz Esmeraldo Áfio ◽  
Paulo Cesar de Almeida ◽  
Márcia Maria Tavares Machado ◽  
Ana Cristina Lindsay ◽  
...  
Keyword(s):  
Reproductive Health ◽  
Reproductive System ◽  
Sexual And Reproductive Health ◽  
Educational Material ◽  
Test Results ◽  
Methodological Development ◽  
Female Reproductive System ◽  
Anatomy And Physiology ◽  
Post Test ◽  
Individual Reading

Abstract Objectives: to evaluate blind women’s learning on the anatomy and physiology of the female reproductive system through the use of an educational material. Methods: methodological development study performed with blind women. The participants responded the pre-test to evaluate their knowledge on sexual and reproductive health and received a manual on anatomy and the reproduction of the physiology After an individual reading, in a period ranging from three to fifteen days, they responded the post-test. Results: there was an increase of correct answers in the post-test in all the items in relation to the categories of The Woman's Body and How One Gets Pregnant becoming significant in the following knowledge of “clitoris increases with the woman excited" (p=0.009), “the function of the vagina in a sexual intercourse "(p<0.001), “How does fertilization occurs”(p<0.001) and "the ovulating period" (p<0.001). Conclusions: the manual enabled the participants to learn about the female anatomy and the physiology of fertilization after educational assistive technology.

Axial forces in the bronchial tree

1977 ◽  
Vol 42 (5) ◽  
pp. 773-781 ◽  
Author(s):  
F. G. Hoppin ◽  
J. M. Hughes ◽  
J. Mead
Keyword(s):  
Airway Pressure ◽  
Axial Stress ◽  
Bronchial Tree ◽  
Forced Expiration ◽  
Axial Forces ◽  
Applied Forces

Dog airways in situ are longer and extend more with inflation than when dissected out. The associated deformation of the parenchyma, from considerations of elasticity, appears to be small. The associated axial forces, to the extent they are transmitted along the tree, are governed by branching angles. Overall, average angles are such as would maintain constant axial stress along the tree and thus favor symmetrical lengthening. But locally, angles indicate considerable variation of transmitted stresses. Since radiography shows relatively homogeneous lengthening, we infer powerful local axial stabilization. In confirmation, dog airways were much less extended by locally applied forces in situ than excised. Do forced expirations apply substantial axial forces? In one subjects, during forced expiration, airway pressure fell abruptly near the carina but calculations showed relatively small axial forces applied to the airway. However, we speculate that large forces may be applied by airway plugs. We conclude that parenchyma stabilizes airway length against variably transmitted axial forces, and, perhaps, forces on airway plugs.

scholarly journals The Effect of Team Game Tournament (TGT) Cooperative Learning Method Application Towards Learning Motivation and Achievement

2017 ◽  
Vol 2 (2) ◽  
pp. 154
Author(s):  
Linda Juwita ◽  
Ni Putu Wulan Purnama Sari ◽  
Yurike Septianingrum
Keyword(s):  
Nursing Students ◽  
Target Population ◽  
Learning Motivation ◽  
Learning Method ◽  
Student Centered ◽  
Student Centered Learning ◽  
Anatomy And Physiology ◽  
Post Test ◽  
Team Game ◽  
Motivation And Achievement

Introduction: Learning method of Team Game Tournament (TGT) has student-centered learning characteristic focuses on students’ knowledge construction in which they could find important information useful for constructing their own knowledge. The continuous weak comprehension of neurology system anatomy and physiology resulted in the application of TGT for constructing students’ knowledge in this study. This study aimed to analyze the efficacy of TGT application for improving learning motivation and achievement in studying neurology system anatomy and physiology among nursing students. Methods: This pre-experimental study used the one group pretest post-test design approach. Target population was all nursing students in two institutions around Surabaya in the even semester of 2016/2017 academic year. Inclusion criteria were passed the course of Biomedical II or Nursing Basics I. Sample size was 143 chose by total sampling. Independent variable was TGT application and dependent variables were learning motivation and achievement. Study instruments were motivation questionnaire and objective test. Data analysis used paired t-test and Mann-Whitney test with α ≤ 0.05. Ethical clearance was issued (number: 449-KEPK). Results: Most respondents were 19 years old single female who chose nursing major because of their dream, and the majority still live with parents in their own house. Only learning motivation data that were normally distributed. TGT application could increase learning motivation and achievement of nursing students significantly (p=0.000 and p=0.028 respectively).  Conclusions: TGT application could increase learning motivation and achievement in studying neurology system anatomy and physiology among nursing students. Further implementation could be broad, other subjects in nursing could be the target in which difficult subject would be underlined. 

Phenotypes of professional bronchial asthma: features of respiratory disorders

2020 ◽  
pp. 20-26
Author(s):  
Antonina Gennadievna Baikova ◽  
Marina Yurievna Vostroknutova ◽  
Dinara Kolgarovna Borisova ◽  
Sergey Anatolievich Babanov
Keyword(s):  
Chronic Obstructive Pulmonary Disease ◽  
Respiratory Distress ◽  
Bronchial Asthma ◽  
Bronchial Tree ◽  
Chronic Obstructive ◽  
Forced Expiration ◽  
Obstructive Pulmonary Disease ◽  
Treatment And Prevention ◽  
Choice Of Treatment

The article is devoted to the study of spirographic indicators FEV1, FEV1/FVC, PEF, MEF75, MEF50, MEF25 as the most informative indicators reflecting the state of bronchial patency at the level of the proximal and distal parts of the bronchial tree in various phenotypes of professional bronchial asthma. Signs of respiratory distress are most pronounced in patients with the phenotype «PBA-occupational chronic obstructive pulmonary disease». Significantly,the» most favorable «spirographic picture in terms of FVC, FEV1, PEF, and MEF25VC is observed in the «PBA allergic» phenotype. Dynamic determination of speed indicators of forced expiration in various phenotypes of professional bronchial asthma can improve the diagnosis of obstructive disorders in this pathology, optimize the choice of treatment and prevention tactics, and predict the course of this pathology.

Ozone-induced airway hyperreactivity in the guinea pig

1984 ◽  
Vol 57 (4) ◽  
pp. 1034-1038 ◽  
Author(s):  
T. Gordon ◽  
C. S. Venugopalan ◽  
M. O. Amdur ◽  
J. M. Drazen
Keyword(s):  
Electrical Stimulation ◽  
Airway Hyperreactivity ◽  
Pulmonary Resistance ◽  
Similar Extent ◽  
Anatomic Site ◽  
Airway Response ◽  
Conducting Airways ◽  
Respiratory Responses ◽  
Stimulation Of

The predominant airway site and mechanism underlying ozone (O3)-induced respiratory hyperresponsiveness was examined in anesthetized guinea pigs and in vitro tissue preparations. Animals exposed to 1.0 or 1.2 ppm O3 (1 h) demonstrated an enhanced airway response to subcutaneous histamine compared with air-exposed animals. The anatomic site of hyperresponsiveness most likely did not involve the parenchyma, since quasi-static deflationary pulmonary compliance was decreased to a similar extent by histamine in air- and O3-preexposed animals. In contrast, the conducting airways were probably involved as changes in pulmonary resistance elicited by subcutaneous histamine were greater in O3- than in air-exposed animals. Neither atropine nor vagotomy abolished this enhanced responsiveness induced by O3. Although vagal interruption did not alter responsiveness, O3-exposed animals demonstrated greater respiratory responses to efferent electrical stimulation of the vagi than air-exposed animals. This suggests the site of hyperresponsiveness may be located distal to the site of efferent stimulation, possibly in the smooth muscle itself or in its microenvironment.

Role of conducting airways in partial separation of inhaled gas mixtures

1977 ◽  
Vol 43 (3) ◽  
pp. 391-396 ◽  
Author(s):  
K. Horsfield ◽  
A. Davies ◽  
G. Cumming
Keyword(s):  
Mass Spectrometer ◽  
Diffusion Coefficients ◽  
Sulfur Hexafluoride ◽  
Reverse Flow ◽  
Gas Mixtures ◽  
Bronchial Tree ◽  
Taylor Dispersion ◽  
Arrival Times ◽  
Conducting Airways

A positive (hollow) cast of the bronchial tree was made from a pig's lung. Gas mixtures containing sulfur hexafluoride (SF6) and helium (He), and SF6 and argon (Ar), were blown down the cast at two different flows, the cast having first been filled with air. Gas was sampled by a mass spectrometer probe from 1-mm-diam branches situated on short, medium, and long pathways. The front of the SF6 appeared in advance of the fronts of the He and the Ar. This relative advancement was greater a) with the SF6/He mixture than with the SF6/Ar mixture; b) at slower flows; and c) on longer pathways. With reverse flow up the cast using SF6/He there was little differences between the arrival times of the two gas fronts at either flow. These results could be explained by the effects of Taylor dispersion on gases having different diffusion coefficients.

Cardiopulmonary Function Abnormalities in Cohort of Adults following Bronchopulmonary Dysplasia as Preterm Infants

2021 ◽  
Author(s):  
Ariane Lasry ◽  
Patrick Kavabushi ◽  
Anne-Marie Canakis ◽  
Thuy M. Luu ◽  
Anne-Monique Nuyt ◽  
...  
Keyword(s):  
Bronchopulmonary Dysplasia ◽  
Chart Review ◽  
Retrospective Chart Review ◽  
Left Ventricular ◽  
Forced Expiration ◽  
Key Points ◽  
Function Test ◽  
And Performance ◽  
Rv Function

Objective This study was aimed to describe the cardiopulmonary profiles of adult patients with bronchopulmonary dysplasia (BPD), comparing them to normative adult values. Study Design This study presents a retrospective chart review of all BPD patients followed in the adult BPD clinic, identified from institutional and archive databases, born preterm at ≤33 weeks estimated gestational age (EGA) between January 1980 and December 2000. Results Forty-four patients with BPD (26.4 ± 2.7 weeks of EGA) were included. Average age at follow-up was 19 years. Majority (61.4%) of the patients had a diagnosis of asthma. Mean spirometry values were: first second of forced expiration (FEV1) 74.1%, forced vital capacity (FVC) 80.7%, and FEV1/FVC 82.5%. Echocardiography (ECHO) images were reviewed, left ventricular (LV) structure and performance did not differ between obstructive and nonobstructive pulmonary function test (PFT) groups, but values of LV longitudinal strain were 4.8% lower than expected normal for adults. Patients with obstructive PFT had additional decreased right ventricular (RV) function by ECHO. Conclusion BPD patients in this study were found to have a burden of cardiorespiratory alterations that persisted into adulthood, with RV performance abnormalities found among patients with obstructive PFT. Key Points

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