Within- and between-day variability of respiratory impedance, using impulse oscillometry in adolescent asthmatics

At present, there are a number of problems associated with the diagnosis of restrictive type of ventilation disorders: first, to identify restriction, it is necessary to perform body plethysmography, which is a laborious technique and requires the active cooperation of the patient with medical personnel; secondly, methodological issues that concern the criteria for the diagnosis of restriction are still under development. Impulse oscillometry (IOS) is a non-invasive and effortless technique for the patient to identify ventilation disorders, especially obstructive ones. In order to assess the informative value of IOS in the diagnosis of the restrictive ventilation disorders, respiratory impedance and its parameters were measured in 82 patients with various bronchopulmonary pathologies. The restriction was established on the basis of spirometric and bodyplethysmography studies. The results showed that IOS is a low-sensitivity method for detecting the restrictive type of ventilation disorders with mild reduced total lung capacity (TLC≥70%pred.), since in this case, the basic parameters of the IOS, such as the resistive component of the respiratory impedance (Rrs) at 5 and 20 Hz (Rrs5 and Rrs20, respectively), as well as the reactive component of the respiratory impedance at 5 Hz (Xrs5) remain within the normal values. When TLC was less than 70%pred., there was a decrease of Xrs5 with an increase in the resonance frequency and the preservation of the normal values of Rrs5 and Rrs20. The abnormal absolute frequency dependence of Rrs was determined at any degree of change in the TLC, increasing as it decreased.

Download Full-text

Reference values of respiratory impedance with impulse oscillometry in healthy Chinese adults

10.21203/rs.3.rs-99501/v1 ◽

2020 ◽

Author(s):

Xiaolin Liang ◽

Yi Gao ◽

Weijie Guan ◽

Jing Du ◽

Li Chen ◽

...

Keyword(s):

Final Analysis ◽

Specific Reference ◽

Respiratory Impedance ◽

Impulse Oscillometry ◽

Chinese Adults ◽

European Respiratory Society ◽

Clinical Trial Registration ◽

Normal Ranges ◽

Normal Individuals ◽

Reference Equations

Abstract Background: Impulse oscillometry (IOS) is a non-invasive pulmonary function test for measuring respiratory impedance. Available reference equations of IOS indices for adults are limited. The aim of this study was to develop reference equations of IOS indices for Chinese adults.Methods: In a multicentral, cross-sessional study of impulse oscillometry in Chinese adults, IOS data from healthy subjects were collected from 19 general hospitals across China was between 2016 and 2018. IOS measurements were conducted in accordance with recommendations of the European Respiratory Society. Multiple linear regression was performed to develop sex-specific reference equations of IOS indices.Results: IOS measurements were performed in 1318 subjects, of which 567 subjects were defined as healthy normal individuals with acceptable IOS data and were included in the final analysis. Reference equations and limits of normal (LLN/ULN) of IOS indices were developed separately for males and females. Height but not age was shown to be the most influential contributor to IOS indices. The reference equations currently used in lung function laboratories predicted higher R5 and X5. Normal ranges of R5 and X5 recommended by the equipment manufacturer were clearly different from the ULN/LLN derived from the reference equations.Conclusions: Reference equations of IOS indices for Chinese adults from a wide region were provided in this study. It is necessary to update new IOS reference equations and adopt ULN/LLN as normal ranges of IOS indices.Clinical Trial Registration: This study was registered at www.clinicaltrials.gov as part of a larger study NCT03467880.

Download Full-text

Effects of deep inspiration (DI) on respiratory impedance measured by impulse oscillometry (IOS)*1

Journal of Allergy and Clinical Immunology ◽

10.1016/j.jaci.2004.01.429 ◽

2004 ◽

Vol 113 (2) ◽

pp. S266-S267

Author(s):

P GAYLOR

Keyword(s):

Deep Inspiration ◽

Respiratory Impedance ◽

Impulse Oscillometry

Download Full-text

Assessment of respiratory impedance during deep-slow breathing with impulse oscillometry in patients with chronic obstructive pulmonary disease

Chinese Journal of Integrative Medicine ◽

10.1007/bf02838612 ◽

2003 ◽

Vol 9 (4) ◽

pp. 266-269

Author(s):

Liang Yong-jie ◽

Cai Ying-yun

Keyword(s):

Chronic Obstructive Pulmonary Disease ◽

Pulmonary Disease ◽

Chronic Obstructive ◽

Respiratory Impedance ◽

Impulse Oscillometry ◽

Obstructive Pulmonary Disease ◽

Slow Breathing

Download Full-text

Reference values of respiratory impedance with impulse oscillometry in healthy Chinese adults

Journal of Thoracic Disease ◽

10.21037/jtd-20-3376 ◽

2021 ◽

Vol 13 (6) ◽

pp. 3680-3691

Author(s):

Xiao-Lin Liang ◽

Yi Gao ◽

Wei-Jie Guan ◽

Jing Du ◽

Li Chen ◽

...

Keyword(s):

Reference Values ◽

Respiratory Impedance ◽

Impulse Oscillometry ◽

Chinese Adults ◽

Healthy Chinese

Download Full-text

Impulse оscillometry in the diagnosis of moderate airway obstruction

Clinical Practice ◽

10.17816/clinpract9433-39 ◽

2018 ◽

Vol 9 (4) ◽

pp. 33-39

Author(s):

O. I. Savushkina ◽

A. V. Chernyak ◽

E. V. Kryukov ◽

A. A. Zaytsev ◽

Zh. K. Naumenko ◽

...

Keyword(s):

Airway Obstruction ◽

Airway Resistance ◽

Respiratory Mechanics ◽

Respiratory Impedance ◽

Impulse Oscillometry ◽

Non Invasive ◽

Invasive Method ◽

Group 2 ◽

Severe Airway Obstruction ◽

Group 1

Background: Impulse oscillometry (IOS) is a non-invasive method for determining respiratory impedance and its parameters. IOS has certain advantages over traditional spirometry. Aim: To assess the potential of IOS in the diagnosis of moderately severe airway obstruction. Methods: We examined 53 patients divided in two groups. The first group consisted of 29 patients (26 males and 3 females aged 42 to 89 years) with moderately severe obstructive abnormalities; the second group included 24 patients (17 males and 7 females aged from 18 to 68 years) without ventilatory defects. Results: Obstructive abnormalities were detected by IOS in 93% of patients in group 1, and the severity of obstruction was more pronounced compared to the results of spirometry in 37% of patients. In group 2, the IOS parameters were normal. There were significant differences in the lung function and IOS parameters between the first and second groups. There were significant correlations between airway resistance and IOS parameters in patients with moderately severe obstructive abnormalities. Conclusion: Thus impulse oscillometry can be used in the clinical practice to diagnose disorders of respiratory mechanics in patients with moderately severe airway obstruction.

Download Full-text

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.

Download Full-text