Small airway dysfunction is an independent dimension of wheezing disease in preschool children

Background. Whether small airway dysfunction (SAD), which is prevalent in asthma, helps to characterize wheezing phenotypes is undetermined. The objective was to assess whether SAD parameters obtained from impedance measurement and asthma probability are linked. Methods. One hundred and thirty-nine preschool children (mean age 4.7 years, 68% boys) suffering from recurrent wheeze underwent impulse oscillometry that allowed calculating peripheral resistance and compliance of the respiratory system (markers of SAD) using the extended RIC model (central and peripheral Resistance, Inertance and peripheral Compliance of the respiratory system). Children were classified using the probability-based approach of GINA guidelines (few, some, most having asthma). A principal component analysis (PCA) that determined the dimensions of wheezing disease evaluated the links between SAD and asthma probability. Results. Forty-seven children belonged to the few, 28 to the some and 64 to the most having asthma groups. Whereas their anthropometrics and measured parameters were similar, the most having asthma group exhibited the lowest mean value of airway inertance after bronchodilator probably due to airway inhomogeneities. PCA characterized nine independent dimensions including a peripheral resistance (constituted by baseline peripheral resistance, AX, R5-20Hz, X5Hz), a central resistance (baseline central resistance, R20Hz) and an airway size dimension (post-bronchodilator inertance and central resistance). PCA showed that the SAD markers were independent from clinical dimensions (control and asthma probability were two other dimensions) and did not help to define wheezing phenotypes. Conclusions. Lung function parameters obtained from impulse oscillometry and asthma probability were belonging to independent dimensions of the wheezing disease.

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Reference values for respiratory system impedance using impulse oscillometry in healthy preschool children

Korean Journal of Pediatrics ◽

10.3345/kjp.2011.54.2.64 ◽

2011 ◽

Vol 54 (2) ◽

pp. 64 ◽

Cited By ~ 26

Author(s):

Jye Hae Park ◽

Jung Won Yoon ◽

Youn Ho Shin ◽

Hye Mi Jee ◽

Young Sun Wee ◽

...

Keyword(s):

Preschool Children ◽

Reference Values ◽

Respiratory System ◽

Impulse Oscillometry

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Predicting asthma exacerbation by impulse oscillometry evaluation of small airway function and fractional exhaled nitric oxide in preschool children

Pediatric Pulmonology ◽

10.1002/ppul.24790 ◽

2020 ◽

Vol 55 (7) ◽

pp. 1601-1607

Author(s):

Shouyan Zheng ◽

Ying Hu ◽

Zhiqiang Chen ◽

Mei Wang ◽

Wei Liao

Keyword(s):

Nitric Oxide ◽

Preschool Children ◽

Asthma Exacerbation ◽

Exhaled Nitric Oxide ◽

Small Airway ◽

Impulse Oscillometry ◽

Fractional Exhaled Nitric Oxide ◽

Airway Function

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Impulse Oscillometric Features and Respiratory System Models Track Small Airway Function in Children

Practical Applications in Biomedical Engineering ◽

10.5772/52579 ◽

2013 ◽

Author(s):

Erika G. ◽

Homer Nazeran ◽

Carlos Ramos ◽

Liza Rodriguez ◽

Lidia Rascon ◽

...

Keyword(s):

Respiratory System ◽

Small Airway ◽

System Models ◽

Airway Function

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Impulse oscillometry for detection of small airway dysfunction in subjects with chronic respiratory symptoms and preserved pulmonary function

Respiratory Research ◽

10.1186/s12931-021-01662-7 ◽

2021 ◽

Vol 22 (1) ◽

Cited By ~ 2

Author(s):

Liang-Yuan Li ◽

Tian-Sheng Yan ◽

Jing Yang ◽

Yu-Qi Li ◽

Lin-Xi Fu ◽

...

Keyword(s):

Pulmonary Function ◽

Respiratory Symptoms ◽

Early Stage ◽

Roc Curves ◽

Diagnostic Value ◽

Small Airway ◽

Impulse Oscillometry ◽

Additional Method ◽

Cutoff Values ◽

Higher Sensitivity

Abstract Background Subjects with chronic respiratory symptoms and preserved pulmonary function (PPF) may have small airway dysfunction (SAD). As the most common means to detect SAD, spirometry needs good cooperation and its reliability is controversial. Impulse oscillometry (IOS) may complete the deficiency of spirometry and have higher sensitivity. We aimed to explore the diagnostic value of IOS to detect SAD in symptomatic subjects with PPF. Methods The evaluation of symptoms, spirometry and IOS results in 209 subjects with chronic respiratory symptoms and PPF were assessed. ROC curves of IOS to detect SAD were analyzed. Results 209 subjects with chronic respiratory symptoms and PPF were included. Subjects who reported sputum had higher R5–R20 and Fres than those who didn’t. Subjects with dyspnea had higher R5, R5–R20 and AX than those without. CAT and mMRC scores correlated better with IOS parameters than with spirometry. R5, R5–R20, AX and Fres in subjects with SAD (n = 42) significantly increased compared to those without. Cutoff values for IOS parameters to detect SAD were 0.30 kPa/L s for R5, 0.015 kPa/L s for R5–R20, 0.30 kPa/L for AX and 11.23 Hz for Fres. Fres has the largest AUC (0.665, P = 0.001) among these parameters. Compared with spirometry, prevalence of SAD was higher when measured with IOS. R5 could detect the most SAD subjects with a prevalence of 60.77% and a sensitivity of 81% (AUC = 0.659, P = 0.002). Conclusion IOS is more sensitive to detect SAD than spirometry in subjects with chronic respiratory symptoms and PPF, and it correlates better with symptoms. IOS could be an additional method for SAD detection in the early stage of diseases.

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A square-pulse flow method for measuring characteristics of the arterial bed

Journal of Applied Physiology ◽

10.1152/jappl.1976.40.3.425 ◽

1976 ◽

Vol 40 (3) ◽

pp. 425-433 ◽

Cited By ~ 3

Author(s):

M. G. Bottomley ◽

G. W. Mainwood

Keyword(s):

Arterial Compliance ◽

Peripheral Resistance ◽

Mean Value ◽

Pressure Response ◽

Arterial System ◽

Response Curves ◽

Arterial Tree ◽

Pulse Flow ◽

Critical Closing Pressure ◽

Closing Pressure

A device was designed to provide a “square” pulse of blood flow into the arterial system. Pulses were injected into the carotid artery of the rabbit during transient cardiac arrest. Analysis of pressure response curves generated by the flow provides information as to the state of the arterial tree. With certain assumptions it is possible to estimate from these curves lumped values of peripheral resistance, critical closing pressure, and arterial compliance. In a series of 12 rabbits the mean value of peripheral resistance was found to be 0.21 +/- 0.7 mmHg-ml-1-min and critical closing pressure was estimated to be 23.6 +/- 3.8 mmHg. This method gives two possible values for arterial compliance 0.036 +/- 0.010 and 0.055 +/- 0.010 ml-mm-1 based, respectively, on the rise and decay curves of the pressure response. The theory and limitations of the method are discussed. The use of the method is illustrated in following the response to increased PCO2 and hemorrhage.

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Clinical Characteristics of and Risk Factors for Small Airway Dysfunction Detected by Impulse Oscillometry

Respiratory Medicine ◽

10.1016/j.rmed.2021.106681 ◽

2021 ◽

pp. 106681

Author(s):

Jieqi Peng ◽

Fan Wu ◽

Heshen Tian ◽

Huajing Yang ◽

Youlan Zheng ◽

...

Keyword(s):

Risk Factors ◽

Clinical Characteristics ◽

Small Airway ◽

Impulse Oscillometry

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Genetic diversity analysis of parental lines for hybrid development in rice (Oryza sativa L.)

Bangladesh Journal of Agricultural Research ◽

10.3329/bjar.v37i4.14386 ◽

2013 ◽

Vol 37 (4) ◽

pp. 617-624 ◽

Cited By ~ 1

Author(s):

MJ Hasan ◽

Umma Kulsum ◽

MMH Rahman ◽

MMH Chowdhury ◽

AZMKA Chowdhury

Keyword(s):

Genetic Diversity ◽

Oryza Sativa L ◽

Principal Component ◽

Mean Value ◽

Cluster Distance ◽

Parental Lines ◽

Almost All ◽

Yield Maximization ◽

Hybrid Development ◽

Panicle Weight

Genetic divergence of 40 parental lines comprising 30 restorer and 10 maintainer lines were studied through Mohalanobis's D2 and principal component analysis for eleven characters. Genotypes were grouped into five different clusters. Cluster V comprised maximum number of genotypes (thirteen) followed by cluster I and II. The inter-cluster distance was maximum between clusters I and V (13.495) indicating wide genetic diversity between these two clusters followed by the distance between cluster I and 11 (9.489), cluster IV, and cluster V (8.969) and cluster I and cluster III (8.039). The minimum inter-cluster distance was observed between cluster II and cluster III (3.034) followed by cluster 111 and cluster IV (3.834) and cluster II and cluster V (4.945) indicating that the genotypes of these clusters were genetically close. The intra cluster distance in the entire five clusters was more or less low which indicated that the genotypes within the same cluster were closely related. Among the characters panicle weight contributed most for divergence in the studied parental lines. Difference in cluster means existed for almost all the characters studied. Highest mean value for number of effective tillers (7.8), days to 50% flowering (95.5), panicles/m2 (192.6), panicle weight (2.9), spikelet fertility (84.8), number of grains/panicle (177.8), days to maturity (123.6), and grain yield/plot (1065.5) were observed in cluster I indicated the parental lines fallen in this cluster having the genetic potentiality to contribute better for yield maximization of hybrid rice. DOI: http://dx.doi.org/10.3329/bjar.v37i4.14386 Bangladesh J. Agril. Res. 37(4): 617-624, December 2012

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Recurrent wheeze and its relationship with lung function and airway inflammation in preschool children: a cross-sectional study in South Korea

BMJ Open ◽

10.1136/bmjopen-2017-018010 ◽

2017 ◽

Vol 7 (10) ◽

pp. e018010 ◽

Cited By ~ 7

Author(s):

Ji Eun Soh ◽

Kyung-Moon Kim ◽

Ji-Won Kwon ◽

Hyung Young Kim ◽

Ju-Hee Seo ◽

...

Keyword(s):

Preschool Children ◽

Lung Function ◽

Airway Inflammation ◽

Allergic Diseases ◽

Cross Sectional Study ◽

Secondary Outcome ◽

Sectional Study ◽

Cross Sectional ◽

Airway Function ◽

Recurrent Wheeze

BackgroundRelationship between recurrent wheeze and airway function and inflammation in preschool children is not fully known.ObjectiveTo investigate the relationship between recurrent wheeze and airway inflammation, lung function, airway hyper-reactivity (AHR) and atopy in preschool children.DesignObservational study, comparing forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and mid-forced expiratory flow (FEF25%–75%), dose–response slope (DRS), exhaled nitric oxide (eNO) and atopic sensitisation between children with recurrent wheeze and those without.SettingPopulation-based, cross-sectional study in Seoul and the Gyeonggi province of Korea conducted as a government-funded programme to perform standardised measurement of the prevalence of allergic diseases, and related factors, in preschool children.Participants900 children aged 4–6 years.Primary and secondary outcome measureseNO, FEV1/FVC, FEF25%–75%, DRS, atopic sensitisation and allergic diseases.MethodsChildren completed the modified International Study of Asthma and Allergies in Childhood questionnaire and underwent eNO assessments, spirometry, methacholine bronchial provocation tests and skin prick tests. Recurrent wheeze was defined as having a lifetime wheeze of more than three episodes, based on the questionnaire. The frequency of hospitalisation and emergency room visits was also obtained by means of the questionnaire. ‘Current’ wheeze was defined as having symptoms or treatments within the past 12 months.ResultsThe prevalence of recurrent wheeze was 13.4%. Children with recurrent wheeze showed a higher prevalence of lifetime or current allergic rhinitis (p=0.01 and p=0.002, respectively) and lifetime atopic dermatitis (p=0.007). Children with recurrent wheeze showed lower FEV1/FVC (p=0.033) and FEF25%–75%(p=0.004), and higher eNO levels (p=0.013) than those without recurrent wheeze. However, the DRS, prevalence of atopic sensitisation and serum IgE levels were not significantly different between the two groups.ConclusionsRecurrent wheeze in preschool children may be associated with airway inflammation and diminished airway function, but not with AHR or atopy.

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