scholarly journals Predicted normal values for maximal respiratory pressures in children

2015 ◽  
Vol 14 (2) ◽  
pp. 187-194 ◽  
Author(s):  
Raíssa De Oliveira Borja ◽  
Tania Fernandes Campos ◽  
Diana Amélia de Freitas ◽  
Thalita Medeiros Fernandes de Macêdo ◽  
Waléria Cristina Miranda de Mendonça ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Reference Values ◽  
Total Lung Capacity ◽  
Normal Values ◽  
Healthy Children ◽  
Residual Volume ◽  
Maximal Inspiratory Pressure ◽  
Predictive Equations ◽  
Lung Capacity ◽  
Reference Equations

Introduction: Reference equations are used to predict normal values for maximal respiratory pressures. Objectives: To develop predictive equations for maximal respiratory pressure in children. Methods: A total of 144 healthy children, aged between 7 and 11 years, were assessed. Maximal inspiratory and expiratory pressures were assessed with a digital manovacuometer on top of residual volume and total lung capacity, respectively. Results: The variables sex, age and weight showed association with maximal inspiratory pressure, while maximal expiratory pressure, in addition to the aforementioned variables, also showed association with height. After regression analysis, only sex and age had an influence on the variability of inspiratory and expiratory pressures. Conclusions: The present study provides reference values and proposes two equation models that predict maximal respiratory pressure values among children aged between 7 and 11 years.

scholarly journals Plasma P-Selectin Is Inversely Associated with Lung Function and Corticosteroid Responsiveness in Asthma

2020 ◽  
Vol 181 (11) ◽  
pp. 879-887
Author(s):  
Mats W. Johansson ◽  
Brandon M. Grill ◽  
Karina T. Barretto ◽  
Molly C. Favour ◽  
Hazel M. Schira ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Severe Asthma ◽  
Total Lung Capacity ◽  
Forced Expiratory Volume ◽  
Residual Volume ◽  
Air Trapping ◽  
Lung Capacity ◽  
University Of Wisconsin ◽  
Multiple Phenotypes ◽  
The University

<b><i>Background:</i></b> Severe asthma has multiple phenotypes for which biomarkers are still being defined. Plasma P-selectin reports endothelial and/or platelet activation. <b><i>Objective:</i></b> To determine if P-selectin is associated with features of asthma in a longitudinal study. <b><i>Methods:</i></b> Plasmas from 70 adult patients enrolled in the Severe Asthma Research Program (SARP) III at the University of Wisconsin-Madison were analyzed for concentration of P-selectin at several points over the course of 3 years, namely, at baseline (BPS), after intramuscular triamcinolone acetonide (TA) injection, and at 36 months after baseline. Thirty-four participants also came in during acute exacerbation and 6 weeks after exacerbation. <b><i>Results:</i></b> BPS correlated inversely with forced expiratory volume in 1 s (FEV<sub>1</sub>) and with residual volume/total lung capacity, an indicator of air trapping. BPS was inversely associated with FEV<sub>1</sub> change after TA, by regression analysis. FEV<sub>1</sub> did not change significantly after TA if BPS was above the median, whereas patients with BPS below the median had significantly increased FEV<sub>1</sub> after TA. BPS was higher in and predicted assignment to SARP phenotype cluster 5 (“severe fixed-airflow asthma”). P-selectin was modestly but significantly increased at exacerbation but returned to baseline within 3 years. <b><i>Conclusions:</i></b> High BPS is associated with airway obstruction, air trapping, the “severe fixed-airflow” cluster, and lack of FEV<sub>1</sub> improvement in response to TA injection. P-selectin concentration, which is a stable trait with only modest elevation during exacerbation, may be a useful biomarker for a severe asthma pheno- or endotype characterized by low pulmonary function and lack of corticosteroid responsiveness.

scholarly journals Predictive equations for total lung capacity and residual volume calculated from radiographs in a random sample of the Michigan population.

Thorax ◽  
1992 ◽  
Vol 47 (7) ◽  
pp. 519-523 ◽  
Author(s):  
K H Kilburn ◽  
R H Warshaw ◽  
J C Thornton ◽  
K Thornton ◽  
A Miller
Keyword(s):  
Random Sample ◽  
Total Lung Capacity ◽  
Residual Volume ◽  
Predictive Equations ◽  
Lung Capacity

STUDIES OF RESPIRATORY PHYSIOLOGY IN CHILDREN

PEDIATRICS ◽  
1959 ◽  
Vol 24 (2) ◽  
pp. 181-193
Author(s):  
C. D. Cook ◽  
P. J. Helliesen ◽  
L. Kulczycki ◽  
H. Barrie ◽  
L. Friedlander ◽  
...  
Keyword(s):  
Tidal Volume ◽  
Respiratory Rate ◽  
Vital Capacity ◽  
Total Lung Capacity ◽  
Lung Compliance ◽  
Respiratory Physiology ◽  
Residual Volume ◽  
Lung Volumes ◽  
Lung Capacity ◽  
Residual Capacity

Tidal volume, respiratory rate and lung volumes have been measured in 64 patients with cystic fibrosis of the pancreas while lung compliance and resistance were measured in 42 of these. Serial studies of lung volumes were done in 43. Tidal volume was reduced and the respiratory rate increased only in the most severely ill patients. Excluding the three patients with lobectomies, residual volume and functional residual capacity were found to be significantly increased in 46 and 21%, respectively. These changes correlated well with the roentgenographic evaluation of emphysema. Vital capacity was significantly reduced in 34% while total lung capacity was, on the average, relatively unchanged. Seventy per cent of the 61 patients had a signficantly elevated RV/TLC ratio. Lung compliance was significantly reduced in only the most severely ill patients but resistance was significantly increased in 35% of the patients studied. The serial studies of lung volumes showed no consistent trends among the groups of patients in the period between studies. However, 10% of the surviving patients showed evidence of significant improvement while 15% deteriorated. [See Fig. 8. in Source Pdf.] Although there were individual discrepancies, there was a definite correlation between the clinical evaluation and tests of respiratory function, especially the changes in residual volume, the vital capacity, RV/ TLC ratio and the lung compliance and resistance.

Fast vs. slow exhalation before O2 inhalation alters subsequent phase III slope

1984 ◽  
Vol 56 (1) ◽  
pp. 52-56 ◽  
Author(s):  
T. S. Hurst ◽  
B. L. Graham ◽  
D. J. Cotton
Keyword(s):  
Total Lung Capacity ◽  
Normal Subjects ◽  
Phase Iii ◽  
Breath Holding ◽  
Small Airways ◽  
Residual Volume ◽  
Lung Capacity ◽  
Single Breath ◽  
Subsequent Phase ◽  
Phase Iii Slope

We studied 10 symptom-free lifetime non-smokers and 17 smokers all with normal pulmonary function studies. All subjects performed single-breath N2 washout tests by either exhaling slowly (“slow maneuver”) from end inspiration (EI) to residual volume (RV) or exhaling maximally (“fast maneuver”) from EI to RV. After either maneuver, subjects then slowly inhaled 100% O2 to total lung capacity (TLC) and without breath holding, exhaled slowly back to RV. In the nonsmokers seated upright phase III slope of single-breath N2 test (delta N2/l) was lower (P less than 0.01) for the fast vs. the slow maneuver, but this difference disappeared when the subjects repeated the maneuvers in the supine position. In contrast, delta N2/l was higher for the fast vs. the slow maneuver (P less than 0.01) in smokers seated upright. For the slow maneuver, delta N2/l was similar between smokers and nonsmokers but for the fast maneuvers delta N2/l was higher in smokers than nonsmokers (P less than 0.01). We suggest that the fast exhalation to RV decreases delta N2/l in normal subjects by decreasing apex-to-base differences in regional ratio of RV to TLC (RV/TLC) but increases delta N2/l in smokers, because regional RV/TLC increases distal to sites of small airways obstruction when the expiratory flow rate is increased.

scholarly journals Physiological Criteria Are Useful for the Diagnosis of Idiopathic Pleuroparenchymal Fibroelastosis

2020 ◽  
Vol 9 (11) ◽  
pp. 3761
Author(s):  
Takato Ikeda ◽  
Yoshiaki Kinoshita ◽  
Yusuke Ueda ◽  
Tomoya Sasaki ◽  
Hisako Kushima ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Total Lung Capacity ◽  
The Body ◽  
Transverse Diameter ◽  
Residual Volume ◽  
Thoracic Cage ◽  
Pleuroparenchymal Fibroelastosis ◽  
Lung Capacity ◽  
Predicted Values ◽  
Diagnostic Sensitivity And Specificity

Background: Diagnostic criteria of idiopathic pleuroparenchymal fibroelastosis (IPPFE) were recently proposed, including physiological criteria of the body mass index (BMI) and percentage of the predicted values of residual volume (RV)/total lung capacity (TLC) (RV/TLC %pred.). The aim of this study was to evaluate (i) whether the physiologic criteria are useful for the diagnosis and (ii) whether the flat chest index, defined as the ratio of the anteroposterior diameter to the transverse diameter of the thoracic cage, could be an alternative parameter to RV/TLC %pred. Methods: We selected consecutive IPPFE patients and idiopathic pulmonary fibrosis (IPF) patients. We examined the diagnostic sensitivity and specificity of the physiological criteria and flat chest index for differentiating IPPFE patients from IPF patients. Results: This study included 37 IPPFE patients and 89 IPF patients. The physiological criteria distinguished IPPFE patients from IPF patients with a sensitivity of 78.6% and specificity of 88.0%. The combination of the flat chest index and BMI was also effective for differentiation (sensitivity of 82.1% and specificity of 89.3%). Conclusion: We verified the good performance of the physiologic criteria in a different cohort. When the RV/TLC is not measured, using the flat chest index instead of RV/TLC %pred. may be reasonable.

Capillary and fiber geometry in rat diaphragm perfusion fixed in situ at different sarcomere lengths

1992 ◽  
Vol 73 (1) ◽  
pp. 151-159 ◽  
Author(s):  
D. C. Poole ◽  
O. Mathieu-Costello
Keyword(s):  
Airway Pressure ◽  
Sarcomere Length ◽  
Total Lung Capacity ◽  
Potential Range ◽  
Residual Volume ◽  
Capillary Length ◽  
Fiber Volume ◽  
Cross Sectional ◽  
Lung Capacity

To determine the potential range of diaphragm sarcomere lengths in situ and the effect of changes in sarcomere length on capillary and fiber geometry, rat diaphragms were perfusion fixed in situ with glutaraldehyde at different airway pressures and during electrical stimulation. The lengths of thick (1.517 +/- 0.007 microns) and thin (1.194 +/- 0.048 microns) filaments were not different from those established for rat limb muscle. Morphometric techniques were used to determine fiber cross-sectional area, sarcomere length, capillary orientation, and capillary length and surface area per fiber volume. All measurements were referenced to sarcomere length, which averaged 2.88 +/- 0.08 microns at -20 to -25 cmH2O airway pressure (residual volume) and 2.32 +/- 0.05 microns at +20 to +26 cmH2O airway pressure (total lung capacity). The contribution of capillary tortuosity and branching to total capillary length was dependent on sarcomere length and varied from 5 to 22%, consistent with that shown previously for mammalian limb muscles over this range of sarcomere lengths. Capillary length per fiber volume [Jv(c,f)] was significantly greater at residual volume (3,761 +/- 193 mm-2) than at total lung capacity (3,142 +/- 118 mm-2) and correlated with sarcomere length [l; r = 0.628, Jv(c,f) = 876l + 1,156, P less than 0.01; n = 18]. We conclude that the diaphragm is unusual in that the apparent in situ minimal sarcomere length is greater than 2.0 microns.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Reference values for pulmonary volumes by plethysmography in a Brazilian sample of white adults

2019 ◽  
Vol 45 (3) ◽  
Author(s):  
Thamine Lessa ◽  
Carlos Alberto de Castro Pereira ◽  
Maria Raquel Soares ◽  
Renato Matos ◽  
Virgínia Pacheco Guimarães ◽  
...  
Keyword(s):  
Reference Values ◽  
Mean Values ◽  
Brazilian Sample ◽  
Lung Capacity ◽  
Upper Limits ◽  
Residual Capacity ◽  
Reference Equations ◽  
Predicted Values ◽  
Pulmonary Volumes ◽  
White Adults

ABSTRACT Objective: To derive reference values for healthy white Brazilian adults who have never smoked and to compare the obtained values with reference values derived by Crapo and by Neder. Methods: Reference equations by quantile regressions were derived in 122 men and 122 women, non-obese, living in seven cities in Brazil. Age ranged from 21 to 92 years in women and from 25 to 88 years in men. Lung function tests were performed using SensorMedics automated body plethysmographies according ATS/ERS recommendations. Lower and upper limits were derived by specific equations for 5 and 95 percentiles. The results were compared to those suggested by Crapo in 1982, and Neder in 1999. Results: Median values for total lung capacity (TLC) were influenced only by stature in men, and by stature and age in women. Residual volume was influenced by age and stature in both genders. Weight was directly related to inspiratory capacity and inversely with functional residual capacity and expiratory reserve volume in both genders. A comparison of observed TLC data with values predicted by Neder equations showed significant lower values by the present data. Mean values were similar between data from present study and those derived by Crapo. Conclusion: New predicted values for lung volumes were obtained in a sample of white Brazilians. The values differ from those derived by Neder, but are similar to those derived by Crapo.

scholarly journals Validation of a protocol to evaluate maximal expiratory pressure using a pressure transducer and a signal conditioner

2011 ◽  
Vol 83 (3) ◽  
pp. 967-972 ◽  
Author(s):  
Viviane Soares ◽  
Fábio B. Rodrigues ◽  
Marcus F. Vieira ◽  
Maria Sebastiana Silva
Keyword(s):  
Pressure Transducer ◽  
Total Lung Capacity ◽  
Respiratory Muscles ◽  
Residual Volume ◽  
Lung Capacity ◽  
Maximal Expiratory Pressure

The respiratory muscles can present fatigue and even chronic inability to generate force. So, reliable devices are necessary to their evaluation. The aim of this study is to evaluate the MEP (Maximal Expiratory Pressure) values of individuals between 20 and 25 years old and to validate a protocol using a pressure transducer and a signal conditioner comparing it with the digital manometer. We evaluated the MEP of 10 participants. They remained seated and made six respiratory maneuvers from Total Lung Capacity (TLC) to Residual Volume (RV). The results in the study showed no statistically significant differences when compared to values reported in the literature, and that the pressure transducer provides reliable values for MEP.

Effect of Lung Volume on Voice Onset Time (VOT)

1993 ◽  
Vol 36 (3) ◽  
pp. 516-520 ◽  
Author(s):  
Jeannette D. Hoit ◽  
Nancy Pearl Solomon ◽  
Thomas J. Hixon
Keyword(s):  
Lung Volume ◽  
Total Lung Capacity ◽  
Voice Onset Time ◽  
Onset Time ◽  
Speech Disorders ◽  
Residual Volume ◽  
Healthy Individuals ◽  
Lung Volumes ◽  
Lung Capacity

This investigation was designed to test the hypothesis that voice onset time (VOT) varies as a function of lung volume. Recordings were made of five men as they repeated a phrase containing stressed /pi/ syllables, beginning at total lung capacity and ending at residual volume. VOT was found to be longer at high lung volumes and shorter at low lung volumes in most cases. This finding points out the need to take lung volume into account when using VOT as an index of laryngeal behavior in both healthy individuals and those with speech disorders.

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