1
|
Identifying bronchoconstriction from the ratio of diaphragm EMG to tidal volume. Respir Physiol Neurobiol 2021; 291:103692. [PMID: 34020067 DOI: 10.1016/j.resp.2021.103692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 05/09/2021] [Accepted: 05/16/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND A fall of ≥ 20 % in forced expiratory volume in the first second (FEV1) with a cumulative dose of histamine ≤ 7.8 μmol is considered to indicate bronchial hyperactivity, but no method exists for patients who cannot perform spirometry properly. Here we hypothesized that increases in respiratory central output measured by chest wall electromyography of the diaphragm (EMGdi-c) expressed as a function of tidal volume (EMGdi-c/VT) would have discriminative power to detect a 'positive' challenge test. METHODS In a physiological study EMGdi was recorded from esophageal electrode (EMGdi-e) in 16 asthma patients and 16 healthy subjects during a histamine challenge test. In a second study, EMGdi from chest wall surface electrodes (EMGdi-c) was measured during a histamine challenge in 44 asthma patients and 51 healthy subjects. VT was recorded from a digital flowmeter during both studies. RESULTS With histamine challenge test the change in EMGdi-e/VT in patients with asthma was significantly higher than that in healthy subjects (104.2 % ± 48.6 % vs 0.03 % ± 17.1 %, p < 0.001). Similarly there was a significant difference in the change of EMGdi-c/VT between patients with asthma and healthy subjects (90.5 % ± 75.5 % vs 2.4 % ± 21.7 %, p < 0.001). At the optimal cut-off point (29 % increase in EMGdi-c/VT), the area under the ROC curve (AUC) for detection of a positive test was 0.91 (p < 0.001) with sensitivity 86 % and specificity 92 %. CONCLUSIONS We conclude that EMGdi-c/VT may be used as an alternative for the assessment of bronchial hypersensitivity and airway reversibility to differentiate patients with asthma from healthy subjects.
Collapse
|
2
|
Lundblad LKA, Blouin N, Grudin O, Grudina L, Drapeau G, Restrepo N, Ducharme FM. Comparing lung oscillometry with a novel, portable flow interrupter device to measure lung mechanics. J Appl Physiol (1985) 2021; 130:933-940. [PMID: 33539262 DOI: 10.1152/japplphysiol.01072.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In the community setting, assessing spirometry in school-aged children is often limited by the unavailability of respirology technicians at the point-of-care. We developed a new technique called the Rapid Expiratory Occlusion Method (REOM) that measures respiratory resistance during normal breathing, without specialized training. The aim was to examine the concordance between respiratory resistance measured with the REOM and respiratory resistance measured by oscillometry on the tremoflo. Children aged 6-17 yr, with or without asthma, received respiratory resistance testing on the tremoflo, then on the REOM. Three to five replicates with a coefficient of variation ≤15% were obtained on each instrument; the primary outcome was the concordance between the average respiratory resistance on the REOM and that measured at 5 Hz (R5) on the tremoflo. Thirty-two children (11 girls; 21 boys) were enrolled with a mean age of 11.2 (range 6-17) yr; after excluding two children not meeting reproducibility criteria, 9 healthy controls, 15 controlled asthmatics, and 6 poorly controlled asthmatics were included. Resistance measured on the REOM showed a strong correlation with R5 measured on the tremoflo (P < 0.0001) with no significant differences on the Bland-Altman analyses. Children and their parents found the REOM easy to use and would consider for home use if recommended by their doctor. With the high concordance between resistance values measured on the REOM and that on the tremoflo combined with perceived ease of use, the REOM appears as a promising means for measuring lung function, thus supporting further testing of other psychometric properties.NEW & NOTEWORTHY We have developed a novel version of the interrupter technique to measure respiratory resistance. The Rapid Expiratory Occlusion Method (REOM) is a small handheld device that measures respiratory resistance and demonstrates excellent correlation with airway oscillometry. With its ease of use, REOM may be promising for use in community practice, patient's homes, and, if paired with a telemedicine application, could enable the healthcare provider to monitor patients in their homes.
Collapse
Affiliation(s)
- Lennart K A Lundblad
- Meakins-Christie Laboratories, McGill University, Montreal, Quebec, Canada.,THORASYS Thoracic Medical Systems Inc., Montreal, Quebec, Canada
| | - Nicolas Blouin
- Clinical Research on Childhood Asthma Research Unit, Research Centre, Sainte-Justine University Health Centre, Montreal, Quebec, Canada
| | - Oleg Grudin
- Spirotech Medical Inc., Montreal, Quebec, Canada
| | - Lyudmila Grudina
- THORASYS Thoracic Medical Systems Inc., Montreal, Quebec, Canada
| | - Guy Drapeau
- THORASYS Thoracic Medical Systems Inc., Montreal, Quebec, Canada
| | - Natalia Restrepo
- THORASYS Thoracic Medical Systems Inc., Montreal, Quebec, Canada
| | - Francine M Ducharme
- Clinical Research on Childhood Asthma Research Unit, Research Centre, Sainte-Justine University Health Centre, Montreal, Quebec, Canada.,Department of Pediatrics, University of Montreal, Montreal, Quebec, Canada.,Depatment of Social and Preventive Medicine, University of Montreal, Montreal, Quebec, Canada
| |
Collapse
|
3
|
Barreto M, Evangelisti M, Montesano M, Martella S, Villa MP. Pulmonary Function Testing in Asthmatic Children. Tests to Assess Outpatients During the Covid-19 Pandemic. Front Pediatr 2020; 8:571112. [PMID: 33313024 PMCID: PMC7707082 DOI: 10.3389/fped.2020.571112] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/22/2020] [Indexed: 12/27/2022] Open
Affiliation(s)
- Mario Barreto
- Pediatric Unit Sant'Andrea Hospital, NESMOS Department, Faculty of Medicine and Psychology, "Sapienza" University, Rome, Italy
| | - Melania Evangelisti
- Pediatric Unit Sant'Andrea Hospital, NESMOS Department, Faculty of Medicine and Psychology, "Sapienza" University, Rome, Italy
| | - Marilisa Montesano
- Pediatric Unit Sant'Andrea Hospital, NESMOS Department, Faculty of Medicine and Psychology, "Sapienza" University, Rome, Italy
| | - Susy Martella
- Pediatric Unit Sant'Andrea Hospital, NESMOS Department, Faculty of Medicine and Psychology, "Sapienza" University, Rome, Italy
| | - Maria Pia Villa
- Pediatric Unit Sant'Andrea Hospital, NESMOS Department, Faculty of Medicine and Psychology, "Sapienza" University, Rome, Italy
| |
Collapse
|
4
|
Foy BH, Kay D. A computational comparison of the multiple-breath washout and forced oscillation technique as markers of bronchoconstriction. Respir Physiol Neurobiol 2017; 240:61-69. [DOI: 10.1016/j.resp.2017.02.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 01/19/2023]
|
5
|
Body fat mass distribution and interrupter resistance, fractional exhaled nitric oxide, and asthma at school-age. J Allergy Clin Immunol 2017; 139:810-818.e6. [DOI: 10.1016/j.jaci.2016.06.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 06/09/2016] [Accepted: 06/16/2016] [Indexed: 02/06/2023]
|
6
|
Special Considerations for Infants and Young Children. PEDIATRIC ALLERGY: PRINCIPLES AND PRACTICE 2016. [PMCID: PMC7271152 DOI: 10.1016/b978-0-323-29875-9.00032-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
7
|
van den Wijngaart LS, Roukema J, Merkus PJFM. Respiratory disease and respiratory physiology: putting lung function into perspective: paediatric asthma. Respirology 2015; 20:379-88. [PMID: 25645369 DOI: 10.1111/resp.12480] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 07/03/2014] [Accepted: 08/03/2014] [Indexed: 01/27/2023]
Abstract
Dealing with paediatric asthma in daily practice, we are mostly interested in the airway function: the hallmark of asthma is the variability of airway patency. Various pulmonary function tests (PFT) can be used to quantify airway caliber in asthmatic children. The choice of the test is based on the developmental age of the child, knowledge of the diagnosis/underlying pathophysiology, clinical questions and reasoning, and treatment. PFT is performed to monitor the severity of asthma and the response to therapy, but can also be used as a diagnostic tool, and to study growth and development of the lungs and airways. This review aims to provide clinicians an overview of the differences in assessing PFT in infants and preschool children compared with older cooperative children, which tests are feasible in infants and young children, the limitations of and usefulness of these tests, and of their interpretation in these age groups.
Collapse
Affiliation(s)
- Lara S van den Wijngaart
- Department of Pediatrics, Division of Respiratory Medicine, Radboud University Medical Centre, Amalia Children's Hospital, Nijmegen, The Netherlands
| | | | | |
Collapse
|
8
|
Haktanir Abul M, Abul Y, Erguven M, Karatoprak EY, Karakurt S, Celikel T. Evaluation of Airway Resistance in Children with Juvenile Idiopathic Arthritis. PEDIATRIC ALLERGY, IMMUNOLOGY, AND PULMONOLOGY 2014; 27:138-142. [PMID: 35923048 DOI: 10.1089/ped.2014.0341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Background: Pneumonitis, pleuritis, and pulmonary interstitial infiltration have been described in patients with juvenile idiopathic arthritis (JIA). However, the pulmonary involvement of JIA is not often clinically apparent. There are few studies based on pulmonary function in children having only a diagnosis of JIA. The aim of the present study is to determine whether children with JIA have airway resistance and flow impairments measured by easily applied interrupter technique. Method: We performed interrupter resistance (Rint) measurements in children with JIA and in healthy control subjects who had no respiratory symptoms or diseases. Results: Fifty-eight children with the diagnosis of JIA (Mean age=12.5±2.75 years; range 7-17 years) and 33 healthy subjects (Mean age=11.8±2.62 years; range 6-16 years) were included in the study. The mean value of tidal peak flow during expiration measured by the interrupter technique was significantly lower in the JIA study group (0.73±0.11 L/s) compared to the healthy control group (0.79±0.08 L/s; p=0.01). Rint values measured during inspiration (Rintinsp) and during expiration (Rintexp) were higher in the JIA study group (Rintinsp=0.28±0.16 Kpa/L/s; Rintexp=0.30±0.50 Kpa/L/s) compared to the healthy control group (Rintinsp=0.26±0.11 Kpa/L/s; Rintexp=0.23±0.08 Kpa/L/s; p>0.05). There was also a positive correlation between C-reactive protein level and median expiratory interrupter resistance (Rintexp; r=0.50, p=0.005). Conclusion: The interrupter technique is a noninvasive and feasible technique and can be used to assess airway abnormalities in children with JIA who cannot successfully complete spirometry.
Collapse
Affiliation(s)
- Mehtap Haktanir Abul
- Department of Pediatric Immunology and Allergy, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey
| | - Yasin Abul
- Department of Pulmonary Medicine, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey
| | - Muferet Erguven
- Pediatric Clinic, Göztepe Education and Training Hospital, Ministry of Health, Istanbul, Turkey
| | - Elif Yuksel Karatoprak
- Pediatric Clinic, Göztepe Education and Training Hospital, Ministry of Health, Istanbul, Turkey
| | - Sait Karakurt
- Department of Pulmonary and Critical Care, Faculty of Medicine, Marmara University, Istanbul, Turkey
| | - Turgay Celikel
- Department of Pulmonary and Critical Care, Faculty of Medicine, Marmara University, Istanbul, Turkey
| |
Collapse
|
9
|
Jabłoński I. Computer assessment of indirect insight during an airflow interrupter maneuver of breathing. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2013; 110:320-332. [PMID: 23639117 DOI: 10.1016/j.cmpb.2013.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 12/13/2012] [Accepted: 01/02/2013] [Indexed: 06/02/2023]
Abstract
The paper answers the questions if it is possible to conclude in objective way on more (than one -Rint - in a classical IT) number of parameters from the time domain post-interrupter signals during the occlusional measurement of respiratory mechanics and also verifies what accuracy can be achieved in such attempt. To obtain reported results, the time-domain enhanced interrupter technique (TD-EIT) was developed in this paper using computer simulations. Three-stage scheme of work was assumed in the project. First, the quality of the model identification was assessed for various combinations of pressure and flow signals recorded during the interruption. Then, the correlation between the working characteristics of the interrupter valve and the precision of the parameter estimation were assessed for the TD-EIT algorithm. Finally, a verification experiment by forward-inverse modeling was organized, in which the mechanical characteristics of a complex model were mapped with reduced analogs and with the use of neural networks for three typical modes: 'Normal state', 'Airway constriction' and 'Cheeks supported'. Obtained results show that to became effective in time-domain post-interrupter data exploration, both pressure and flow signals should be used in assessment of respiratory mechanics, taken in a range of at least 100ms and when both slopes (valve closing and opening) of quasi-step excitation are included. What is more, the faster the valve the smaller error of parameter estimation in proposed TD-EIT was observed, and this uncertainty importantly falls down for the length of time window exceeding the limit of 100ms. The pioneering use of neural network for mapping the mechanical properties of lungs with the use of interrupter experiment methodology proves that it is possible to conclude about more (than one) number of parameters characterizing the complex system and that this insight is biased with the error not exceeding of 10%; only peripheral properties are estimated worse. Such observation has a potential to change the experimental protocol, which was used in interrupter measurements up to date and to make this technique more attractive in comparison to other method, i.e. forced oscillation technique or impulse oscillometry. As regards the practical meaning of reported results for engineers and end-users (physicians and patients), proposed solution can be applied in simple portable devices with a feature of easy operation (important for e-monitoring).
Collapse
Affiliation(s)
- Ireneusz Jabłoński
- Wroclaw University of Technology, Chair of Electronic and Photonic Metrology, 50-317 Wroclaw, ul. B. Prusa 53/55, Poland.
| |
Collapse
|
10
|
Beydon N, Mahut B, Maingot L, Guillo H, La Rocca MC, Medjahdi N, Koskas M, Boulé M, Delclaux C. Baseline and post-bronchodilator interrupter resistance and spirometry in asthmatic children. Pediatr Pulmonol 2012; 47:987-93. [PMID: 22328540 DOI: 10.1002/ppul.22526] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Accepted: 12/31/2011] [Indexed: 11/11/2022]
Abstract
In children unable to perform reliable spirometry, the interrupter resistance (R(int) ) technique for assessing respiratory resistance is easy to perform. However, few data are available on the possibility to use R(int) as a surrogate for spirometry. We aimed at comparing R(int) and spirometry at baseline and after bronchodilator administration in a large population of asthmatic children. We collected retrospectively R(int) and spirometry results measured in 695 children [median age 7.8 (range 4.8-13.9) years] referred to our lab for routine assessment of asthma disease. Correlations between R(int) and spirometry were studied using data expressed as z-scores. Receiver operator characteristic curves for the baseline R(int) value (z-score) and the bronchodilator effect (percentage predicted value and z-score) were generated to assess diagnostic performance. At baseline, the relationship between raw values of R(int) and FEV(1) was not linear. Despite a highly significant inverse correlation between R(int) and all of the spirometry indices (FEV(1) , FVC, FEV(1) /FVC, FEF(25-75%) ; P < 0.0001), R(int) could detect baseline obstruction (FEV(1) z-score ≤ -2) with only 42% sensitivity and 95% specificity. Post-bronchodilator changes in R(int) and FEV(1) were inversely correlated (rhô = -0.50, P < 0.0001), and R(int) (≥35% predicted value decrease) detected FEV(1) reversibility (>12% baseline increase) with 70% sensitivity and 69% specificity (AUC = 0.79). R(int) measurements fitted a one-compartment model that explained the relationship between flows and airway resistance. We found that R(int) had poor sensitivity to detect baseline obstruction, but fairly good sensitivity and specificity to detect reversibility. However, in order to implement asthma guidelines for children unable to produce reliable spirometry, bronchodilator response measured by R(int) should be systematically studied and further assessed in conjunction with clinical outcomes.
Collapse
Affiliation(s)
- Nicole Beydon
- AP-HP, Unité Fonctionnelle d'Explorations Fonctionnelles Respiratoires, Hôpital Armand-Trousseau, Paris, France.
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Arnold DH, Gebretsadik T, Abramo TJ, Hartert TV. Noninvasive testing of lung function and inflammation in pediatric patients with acute asthma exacerbations. J Asthma 2011; 49:29-35. [PMID: 22133263 DOI: 10.3109/02770903.2011.637599] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE There is limited information on performance rates for tests of lung function and inflammation in pediatric patients with acute asthma exacerbations. We sought to examine how frequently pediatric patients with acute asthma exacerbations could perform noninvasive lung function and exhaled nitric oxide (FE(NO)) testing and participant characteristics associated with successful performance. METHODS We studied a prospective convenience sample aged 5-17 years with acute asthma exacerbations in a pediatric emergency department. Participants attempted spirometry for percent predicted forced expiratory volume in 1 second (%FEV(1)), airway resistance (Rint), and FE(NO) testing before treatment. We examined overall performance rates and the associations of age, gender, race, and baseline acute asthma severity score with successful test performance. RESULTS Among 573 participants, age was (median [interquartile range]) 8.8 [6.8, 11.5] years, 60% were male, 57% were African-American, and 58% had Medicaid insurance. Tests were performed successfully by the following [n (%)]: full American Thoracic Society-European Respiratory Society criteria spirometry, 331 (58%); Rint, 561 (98%); and FE(NO), 354 (70% of 505 attempted test). Sixty percent with mild-moderate exacerbations performed spirometry compared to 17% with severe exacerbations (p = .0001). Participants aged 8-12 years (67%) were more likely to perform spirometry than those aged 5-7 years (48%) (OR = 2.23, 95% CI: 1.45-3.11) or 13-17 years (58%) (OR = 1.61, 95% CI: 1.00-2.59). CONCLUSIONS There is clinically important variability in performance of these tests during acute asthma exacerbations. The proportion of patients with severe exacerbations able to perform spirometry (17%) limits its utility. Almost all children with acute asthma can perform Rint testing, and further development and validation of this technology is warranted.
Collapse
Affiliation(s)
- Donald H Arnold
- Department of Pediatrics, Division of Emergency Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA.
| | | | | | | |
Collapse
|
12
|
Clinical Applications of Pediatric Pulmonary Function Testing: Lung Function in Recurrent Wheezing and Asthma. PEDIATRIC ALLERGY IMMUNOLOGY AND PULMONOLOGY 2011; 24:69-76. [DOI: 10.1089/ped.2010.0060] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
13
|
Nakajima N, Mochizuki H, Muramatsu R, Hagiwara S, Mizuno T, Arakawa H. Relationship between exhaled nitric oxide and small airway lung function in normal and asthmatic children. Allergol Int 2011; 60:53-9. [PMID: 21099248 DOI: 10.2332/allergolint.10-oa-0215] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Accepted: 07/24/2010] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND In children, exhaled nitric oxide (eNO) is usually confounded by factors such as age and height. We evaluated the relationship between eNO and lung function by minimizing the effects of aging and height. METHODS In Study 1, the subjects comprised 738 elementary school children and junior high school children (aged 6 to 15 years, 366 males and 372 females). They were divided into two groups according to age (6-10 years and 11-15 years). A height range was determined by a histogram of height in each group. In Study 2, lung function, respiratory resistance and eNO level were measured in age- and height-limited groups. RESULTS In Study 1, total of 148 younger children ranging in height from 120 to 130 cm and 180 older children ranging in height from 148 to 158 cm participated in Study 2. The level of eNO among asthmatic children was higher than that of normal children in both the younger and the older groups. The decrease in forced expiratory volume in 1 second (FEV(1)) and other parameters of central airway resistance did not correlate with the eNO level. However, the small airway parameters of MMEF and V(25)/HT in older asthmatic children, and V(25)/HT and R(5)-R(20) in younger asthmatic children inversely correlated with eNO. CONCLUSIONS Our data suggest that eNO level inversely correlates with small airway narrowing, and airway inflammation has a significant effect on small airway lung function in asthmatic school children.
Collapse
Affiliation(s)
- Naoki Nakajima
- Department of Pediatrics, Gunma University Graduate School of Medicine, Gunma, Japan
| | | | | | | | | | | |
Collapse
|
14
|
Komarow HD, Myles IA, Uzzaman A, Metcalfe DD. Impulse oscillometry in the evaluation of diseases of the airways in children. Ann Allergy Asthma Immunol 2011; 106:191-9. [PMID: 21354020 PMCID: PMC3401927 DOI: 10.1016/j.anai.2010.11.011] [Citation(s) in RCA: 139] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 09/15/2010] [Accepted: 11/09/2010] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To provide an overview of impulse oscillometry and its application to the evaluation of children with diseases of the airways. DATA SOURCES Medline and PubMed search, limited to English language and human disease, with keywords forced oscillation, impulse oscillometry, and asthma. STUDY SELECTIONS The opinions of the authors were used to select studies for inclusion in this review. RESULTS Impulse oscillometry is a noninvasive and rapid technique requiring only passive cooperation by the patient. Pressure oscillations are applied at the mouth to measure pulmonary resistance and reactance. It is employed by health care professionals to help diagnose pediatric pulmonary diseases such asthma and cystic fibrosis; assess therapeutic responses; and measure airway resistance during provocation testing. CONCLUSIONS Impulse oscillometry provides a rapid, noninvasive measure of airway impedance. It may be easily employed in the diagnosis and management of diseases of the airways in children.
Collapse
Affiliation(s)
- Hirsh D Komarow
- Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892-1960, USA.
| | | | | | | |
Collapse
|
15
|
Jabłoński I, Polak AG, Mroczka J. Preliminary study on the accuracy of respiratory input impedance measurement using the interrupter technique. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2011; 101:115-125. [PMID: 21146246 DOI: 10.1016/j.cmpb.2010.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Revised: 10/22/2010] [Accepted: 11/10/2010] [Indexed: 05/30/2023]
Abstract
Respiratory input impedance contains information about the state of pulmonary mechanics in the frequency domain. In this paper the possibility of respiratory impedance measurement by interrupter technique as well as the accuracy of this approach are assessed. Transient states of flow and pressure recorded during expiratory flow interruption are simulated with a complex, linear model for the respiratory system and then used to calculate the impedance, including three states of respiratory mechanics and the influence of the measurement noise. The results of computations are compared to the known, theoretical impedance of the model. At 1 kHz sampling rate, the optimal time window lays between 100 and 200 ms and is centred around the pressure jump caused by the flow interruption. The proposed algorithm yields satisfactory accuracy in the range from 10 to 400 Hz, particularly to 150 Hz. Depending on the simulated respiratory system state, the error of calculated impedance (relative Euclidean distance between the vectors of computed and theoretical values), for the window of 190 ms, varies between 5.0% and 7.1%.
Collapse
Affiliation(s)
- Ireneusz Jabłoński
- Chair of Electronic and Photonic Metrology, Wrocław University of Technology, ul. B. Prusa 53/55, 50-317 Wrocław, Poland.
| | | | | |
Collapse
|
16
|
Calogero C, Parri N, Baccini A, Cuomo B, Palumbo M, Novembre E, Morello P, Azzari C, de Martino M, Sly PD, Lombardi E. Respiratory impedance and bronchodilator response in healthy Italian preschool children. Pediatr Pulmonol 2010; 45:1086-94. [PMID: 20672294 DOI: 10.1002/ppul.21292] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVE To define normal values for respiratory resistance (R(rs)) and reactance (X(rs)) and bronchodilator response (BDR) in a population of healthy Italian preschool children using a commercially available forced oscillation device. METHODS R(rs) and X(rs) were measured in kindergartens in Viterbo, Italy. Regression analysis was performed taking into account height, weight, age, gender, and reference equations calculated. The coefficient of repeatability (CR) between two tests performed 15 min apart was calculated in a subset of children. BDR was assessed by repeating the measurements 15 min after the administration of 200 µg of inhaled salbutamol and calculated as an absolute change in R(rs) and X(rs) at 8 Hz, as a percent change in baseline, and as a change in Z-score calculated from the reference equations. RESULTS Lung function was attempted in 175 healthy children and successful in 163 (81 male, median age 4.8, range 2.9-6.1 years). R(rs) and X(rs) at 6, 8, and 10 Hz were related to height but not other variables. The CR was 1.53 hPa s L(-1) for R(rs8) and 0.91 hPa s L(-1) for X(rs8). The 5th percentile for absolute R(rs8) BDR was -3.16 hPa s L(-1), whereas the 95th percentile for absolute X(rs8) BDR was 2.25 hPa s L(-1). These cut-off values corresponded to a change in the Z-score of -1.88 and 2.48, respectively. CONCLUSIONS We have established reference equations for R(rs) and X(rs) in healthy Italian preschool children using forced oscillations. We recommend a change in Z-score of -1.88 for R(rs8) and 2.48 for X(rs8) as cut-off values for a positive BDR.
Collapse
Affiliation(s)
- C Calogero
- Section of Respiratory Medicine, Department of Paediatrics, University of Florence, Anna Meyer University Hospital for Children, Florence, Italy.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Mele L, Sly PD, Calogero C, Bernardini R, Novembre E, Azzari C, de Martino M, Lombardi E. Assessment and validation of bronchodilation using the interrupter technique in preschool children. Pediatr Pulmonol 2010; 45:633-8. [PMID: 20575101 DOI: 10.1002/ppul.21210] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To determine and validate a cut-off value for bronchodilation using the interrupter resistance (Rint) in preschool children. PATIENTS AND METHODS Rint was measured in 60 healthy children (age range 2.7-6.4 years) before and after salbutamol inhalation (200 microg). Four potential methods for assessing BDR were evaluated: percent change from baseline, percent change of predicted values, absolute change in Rint, and change in Z-score. These cut-off values, determined as the fifth percentile of the healthy group, were applied to children referred for the assessment of recurrent wheezing, classified on the basis of acute symptoms and/or abnormal chest examination into symptomatic (n = 60, age range 2.9-6.1 years) and asymptomatic (n = 60, age range 2.5-5.7 years) groups. RESULTS The cut-off values for bronchodilation calculated in healthy children were: -32% baseline; -33% predicted; -0.26 kPa L(-1) sec; and -1.25 Z-scores. Assessing BDR in children with a history of wheezing by either a decrease in absolute Rint or a decrease in Z-score gave sensitivity, specificity, negative predictive value, and positive predictive value all >80% for detecting children with current respiratory symptoms. CONCLUSIONS Both a decrease in Rint > or =0.26 kPa L(-1) sec and a decrease in Z-score of > or =1.25 are appropriate for assessing BDR in preschool children with a history of recurrent wheezing. As Z-score is a more general solution, we recommend using a change in Z-score to determine BDR in preschool children. Further longitudinal studies will be required to determine the clinical utility of measuring BDR in managing lung disease in such children.
Collapse
Affiliation(s)
- Laura Mele
- Department of Pediatrics, University of Florence, Florence, Italy
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Gangell CL, Hall GL, Stick SM, Sly PD. Lung function testing in preschool-aged children with cystic fibrosis in the clinical setting. Pediatr Pulmonol 2010; 45:419-33. [PMID: 20425849 DOI: 10.1002/ppul.21192] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In cystic fibrosis (CF) lung function testing is a means of monitoring progression of lung disease. The preschool years have often been referred to as the "silent years" due to the previous lack suitable measures of lung function testing in this age group. This review outlines the various techniques of lung function testing in preschool children with CF in the clinical setting. This includes measures requiring tidal breathing including the forced oscillation technique, the interrupter technique, plethysmography, and multiple breath washout, as well as spirometry that requires respiratory maneuvers. We describe the feasibility and variability of different lung function methods used in preschoolers and report measurements made during tidal breathing have greater feasibility, although greater variability compared to spirometry. We also report associations with lung function and markers of CF lung disease. In the preschool age group measurements made during tidal breathing may be more appropriate in the clinic setting than those that require a higher degree of cooperation and specific respiratory maneuvers.maneuvers.
Collapse
Affiliation(s)
- Catherine L Gangell
- Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, Perth, Western Australia, Australia.
| | | | | | | | | |
Collapse
|
19
|
Li AM, Lam HS, So HK, Leung M, Tsen T, Au CT, Chang AB. Interrupter Respiratory Resistance in Healthy Chinese Preschool Children. Chest 2009; 136:554-560. [DOI: 10.1378/chest.08-2798] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
|
20
|
Reddel HK, Taylor DR, Bateman ED, Boulet LP, Boushey HA, Busse WW, Casale TB, Chanez P, Enright PL, Gibson PG, de Jongste JC, Kerstjens HAM, Lazarus SC, Levy ML, O'Byrne PM, Partridge MR, Pavord ID, Sears MR, Sterk PJ, Stoloff SW, Sullivan SD, Szefler SJ, Thomas MD, Wenzel SE. An Official American Thoracic Society/European Respiratory Society Statement: Asthma Control and Exacerbations. Am J Respir Crit Care Med 2009; 180:59-99. [DOI: 10.1164/rccm.200801-060st] [Citation(s) in RCA: 1321] [Impact Index Per Article: 88.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
|
21
|
Song TW, Kim KW, Kim ES, Park JW, Sohn MH, Kim KE. Utility of impulse oscillometry in young children with asthma. Pediatr Allergy Immunol 2008; 19:763-8. [PMID: 18331417 DOI: 10.1111/j.1399-3038.2008.00734.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Impulse Oscillometry (IOS) was developed as a tool to measure lung function, and as it only requires passive cooperation, it has been successfully used in younger children. The aim of this study was to assess the utility of IOS compared to conventional spirometry for lung function measures in asthmatic Korean children aged 3 to 6 yrs. Total serum IgE levels, total eosinophil counts, and specific IgE levels were measured in 77 children with asthma and 55 control subjects. IOS and spirometry were performed in the children before and after bronchodilator administration. Asthmatic children significantly differed from control subjects in baseline resistance at 10 Hz and in their IOS-assessed bronchodilator responses through a Delta resistance at 5 Hz (mean, -27.4% vs. -13.1%; p = 0.002), 10 Hz (mean, -20.4% vs. -11.5%; p = 0.012), 20 Hz (mean, -16.4% vs. -9.4%; p = 0.016), and 35 Hz (mean, -17.2% vs. -10.2%; p = 0.020). Conventional spirometry did not show statistically significant findings. Asthmatic children significantly differed from control subjects in IOS-assessed bronchodilator response through a Delta resistance at 5 Hz, both in atopic children and in non-atopic children. For atopic children, atopic asthmatic children (n = 58) also significantly differed from atopic controls (n = 30) in baseline resistance at 10 Hz, 20 Hz, 35 Hz and impedance and in IOS-assessed bronchodilator responses through a Delta resistance at 10 Hz and 35 Hz. There were some significant correlations between bronchodilator responses of spirometric parameters and IOS parameters. IOS is useful diagnostic tool in early asthma development and might be a helpful objective outcome measure of early interventions.
Collapse
Affiliation(s)
- Tae Won Song
- Division of Allergy and Respiratory Medicine, Department of Pediatrics, Ilsan Paik Hospital, Inje University College of Medicine, Goyang-si, Korea
| | | | | | | | | | | |
Collapse
|
22
|
Abstract
Measurement of lung function is routine in older children and adults with cystic fibrosis (CF) but not in infants and preschool children. Pulmonary infection, neutrophil-dominated inflammation and clinical exacerbations in young children similar to those seen in older subjects have been identified and highlight the urgent need to evaluate lung function in early life. Mounting evidence suggests lung function techniques sensitive to changes in peripheral lung function may be required to detect the early functional abnormalities in infants and preschool children with CF. In addition, the majority of studies in young children with CF have not reported longitudinal data and therefore the prognostic potential of existing lung function methods to track disease progression is poorly understood. This review aims to describe recent research findings in infants and preschool children and to outline currently available lung function techniques, issues around their standardization and their relative advantages and disadvantages in young children with CF.
Collapse
|
23
|
Lebras-Isabet MN, Denjean A. [Respiratory function tests in children aged 3-6 years with cystic fibrosis: indications and execution]. REVUE DE PNEUMOLOGIE CLINIQUE 2007; 63:313-318. [PMID: 18166934 DOI: 10.1016/s0761-8417(07)74208-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Affiliation(s)
- M-N Lebras-Isabet
- Service de Gastroentérologie, Mucoviscidose et Nutrition Pédiatriques (Pr Cezard), CRCM, Hôpital Robert-Debré, 48 boulevard Sérurier, 75019 Paris.
| | | |
Collapse
|
24
|
Park JW, Lee YW, Jung YH, Park SE, Hong CS. Impulse oscillometry for estimation of airway obstruction and bronchodilation in adults with mild obstructive asthma. Ann Allergy Asthma Immunol 2007; 98:546-52. [PMID: 17601267 DOI: 10.1016/s1081-1206(10)60733-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Clinical validity of impulse oscillometry (IOS) for the evaluation of airway obstruction and bronchodilation is a controversial issue in adults with asthma. METHODS This study enrolled 195 outpatients from October 1998 to October 2004. We performed IOS in 158 asthmatic adults, including 70 asthmatic adults with a forced expiratory volume in 1 second (FEV,) reversibility (group 1), 88 asthmatic adults with hyperresponsiveness to methacholine or sputum eosinophilia (group 2) who did not meet the FEV, criteria, and 37 nonasthmatic adults (group 3). RESULTS Baseline respiratory resistance at 5 Hz (R5), respiratory resistance at 10 Hz, frequency dependency of resistance (R5 to 2)), and resonance frequency were discriminative between asthmatic patients and nonasthmatic patients. The IOS parameters were decreased after bronchodilation in both asthmatic groups compared with the nonasthmatic group. Among these patients, R5 and R5 to 21 were the most discriminative parameters for evaluation of bronchodilation. Approximately one third of the patients with positive methacholine challenge test results or sputum eosinophilia manifested bronchodilation evaluated by these IOS parameters. Overall sensitivities of these parameters were comparable to FEV, for diagnosis of bronchodilation in 158 asthmatic adults. Logistic regression analysis showed that R5 to 20 was the most reliable parameter for prediction of R5 reversibility for all asthmatic adults. CONCLUSIONS IOS may complement the estimation of obstruction and bronchodilation for asthmatic adults. Its discriminative power for airway obstruction and sensitivities for bronchodilation were comparable to FEV,.
Collapse
Affiliation(s)
- Jung-Won Park
- Department of Internal Medicine, Institute of Allergy, Brain Korea 21.
| | | | | | | | | |
Collapse
|
25
|
Beydon N, M'buila C, Bados A, Peiffer C, Bernard A, Zaccaria I, Denjean A. Interrupter resistance short-term repeatability and bronchodilator response in preschool children. Respir Med 2007; 101:2482-7. [PMID: 17720469 DOI: 10.1016/j.rmed.2007.07.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2007] [Revised: 07/04/2007] [Accepted: 07/11/2007] [Indexed: 11/22/2022]
Abstract
UNLABELLED Interrupter resistance (Rint) technique can be easily and successfully performed in preschool children. The establishment of Rint short-term repeatability is essential to interpret any Rint change after a pharmacological intervention. AIMS OF THE STUDY In preschool children with asthma or chronic cough: (1) to assess two indices of short-term repeatability: (a) intra-measurement and (b) within-occasion between-test repeatability; (2) to study the relationship between short-term repeatability and bronchodilator response (BDR). RESULTS Rint intra-measurement repeatability assessed by the coefficient of variation was similar at baseline and after bronchodilator in asthmatics and in coughers (median 10% and 12%, respectively). There was no significant difference between asthmatics and coughers for both coefficient of repeatability (CR) (0.25 kPa L(-1)s and 32% of predicted vs 0.16 kPa L(-1) s and 21% of predicted, respectively) and BDR (median -14.7% vs -21.1% of predicted, respectively). However, in 20% of the study children, baseline variability of Rint modified the significance of the BDR. CONCLUSION In the present study, Rint short-term repeatability was similar to that of previous studies. Similar Rint repeatability in coughers and in asthmatic children favored the use of asthmatic CR for both populations, and a -35% cut-off as a positive BDR. In 20% of study children, baseline Rint variability could influence the significance of the BDR. In order to improve assessment of BDR using Rint, further studies are needed (1) to compare the variability of Rint to other resistance measurement techniques and (2) to define the best method for Rint calculation and for expression of BDR.
Collapse
Affiliation(s)
- Nicole Beydon
- Physiology Department, Robert Debré Hospital, 48 Bd Sérurier, 75019 Paris, France.
| | | | | | | | | | | | | |
Collapse
|
26
|
Beydon N, Davis SD, Lombardi E, Allen JL, Arets HGM, Aurora P, Bisgaard H, Davis GM, Ducharme FM, Eigen H, Gappa M, Gaultier C, Gustafsson PM, Hall GL, Hantos Z, Healy MJR, Jones MH, Klug B, Lødrup Carlsen KC, McKenzie SA, Marchal F, Mayer OH, Merkus PJFM, Morris MG, Oostveen E, Pillow JJ, Seddon PC, Silverman M, Sly PD, Stocks J, Tepper RS, Vilozni D, Wilson NM. An official American Thoracic Society/European Respiratory Society statement: pulmonary function testing in preschool children. Am J Respir Crit Care Med 2007; 175:1304-45. [PMID: 17545458 DOI: 10.1164/rccm.200605-642st] [Citation(s) in RCA: 804] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
|
27
|
Evans TM, Rundell KW, Beck KC, Levine AM, Baumann JM. Impulse oscillometry is sensitive to bronchoconstriction after eucapnic voluntary hyperventilation or exercise. J Asthma 2007; 43:49-55. [PMID: 16448966 DOI: 10.1080/02770900500448555] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Airway responses were compared following 6-minute eucapnic voluntary hyperventilation and 6-minute exercise challenges by examining resting and post-challenge impulse oscillometry and spirometry variables. Twenty-two physically active individuals with probable exercise-induced bronchoconstriction took part in this study. Impulse oscillometry and spirometry were performed at baseline and for 20 minutes post-challenge at 5-minute intervals. High correlation was found between the two measures of change in airway function for both methods of challenge. Impulse oscillometry detected a difference in degree of response to the challenges, whereas spirometry indicated no difference, suggesting that impulse oscillometry is a more sensitive measure of change in airway function.
Collapse
Affiliation(s)
- Tina M Evans
- Marywood University, Scranton, Pennsylvania 18509, USA.
| | | | | | | | | |
Collapse
|
28
|
Thamrin C, Gangell CL, Udomittipong K, Kusel MMH, Patterson H, Fukushima T, Schultz A, Hall GL, Stick SM, Sly PD. Assessment of bronchodilator responsiveness in preschool children using forced oscillations. Thorax 2007; 62:814-9. [PMID: 17412777 PMCID: PMC2117298 DOI: 10.1136/thx.2006.071290] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The forced oscillation technique (FOT) requires minimal patient cooperation and is feasible in preschool children. Few data exist on respiratory function changes measured using FOT following inhaled bronchodilators (BD) in healthy young children, limiting the clinical applications of BD testing in this age group. A study was undertaken to determine the most appropriate method of quantifying BD responses using FOT in healthy young children and those with common respiratory conditions including cystic fibrosis, neonatal chronic lung disease and asthma and/or current wheeze. METHODS A pseudorandom FOT signal (4-48 Hz) was used to examine respiratory resistance and reactance at 6, 8 and 10 Hz; 3-5 acceptable measurements were made before and 15 min after the administration of salbutamol. The post-BD response was expressed in absolute and relative (percentage of baseline) terms. RESULTS Significant BD responses were seen in all groups. Absolute changes in BD responses were related to baseline lung function within each group. Relative changes in BD responses were less dependent on baseline lung function and were independent of height in healthy children. Those with neonatal chronic lung disease showed a strong baseline dependence in their responses. The BD response in children with cystic fibrosis, asthma or wheeze (based on both group mean data and number of responders) was not greater than in healthy children. CONCLUSIONS The BD response assessed by the FOT in preschool children should be expressed as a relative change to account for the effect of baseline lung function. The limits for a positive BD response of -40% and 65% for respiratory resistance and reactance, respectively, are recommended.
Collapse
Affiliation(s)
- Cindy Thamrin
- Telethon Institute for Child Health Research, P O Box 855, West Perth, WA 6872, Australia
| | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Wee YS, Kim HY, Jung DW, Park HW, Shin YH, Han MY. Reference values for respiratory system impedance using impulse oscillometry in school-aged children in Korea. KOREAN JOURNAL OF PEDIATRICS 2007. [DOI: 10.3345/kjp.2007.50.9.862] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Young Sun Wee
- Department of Pediatrics, College of Medicine, Pochon CHA University, Sungnam, Korea
| | - Hyoung Yun Kim
- Department of Pediatrics, College of Medicine, Pochon CHA University, Sungnam, Korea
| | - Da Wun Jung
- Department of Pediatrics, College of Medicine, Pochon CHA University, Sungnam, Korea
| | - Hye Won Park
- Department of Pediatrics, College of Medicine, Pochon CHA University, Sungnam, Korea
| | - Yoon Ho Shin
- Department of Pediatrics, College of Medicine, Pochon CHA University, Sungnam, Korea
| | - Man Yong Han
- Department of Pediatrics, College of Medicine, Pochon CHA University, Sungnam, Korea
| |
Collapse
|
30
|
Affiliation(s)
- Yong-Mean Park
- Department of Pediatrics, Konkuk University School of Medicine, Seoul, Korea
| |
Collapse
|
31
|
Gotshall RW. Airway response during exercise and hyperpnoea in non-asthmatic and asthmatic individuals. Sports Med 2006; 36:513-27. [PMID: 16737344 DOI: 10.2165/00007256-200636060-00005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Airway calibre is an important determinant of air flow and respiratory work both at rest and during exercise. While much is understood about control of airway calibre at rest, less is known about the dynamics and changes in airway resistance during exercise, especially in those with asthma. This article provides an overview of the current understanding provided by the literature that has addressed airway resistance during exercise in normal non-asthmatic individuals and in those with asthma. There are many interesting studies that provide some insight into this issue. In general, non-asthmatic individuals appear to have near maximally or maximally dilated airways at rest and, thus, have little change associated with exercise, at least during short duration exercise of <15 minutes. However, potent bronchodilating influences are in operation during the exercise as shown by exercise data from normal subjects with pharmacologically pre-constricted airways. In contrast, dynamic exercise has consistently demonstrated improved airway calibre in asthmatic individuals. Again, the exercise has typically been <15 minutes. Data from longer duration exercise (20-30 minutes) are lacking in normal subjects but suggest declining pulmonary function over time during exercise in asthmatic individuals after the initial bronchodilation. However, the lack of non-asthmatic controls and small subject numbers in these studies leave much remaining to be studied in this regard. Handgrip exercise in asthmatic individuals also elicits bronchodilation raising interesting questions as to potential mechanisms. Isocapnic voluntary hyperpnoea matched to exercise hyperpnoea levels induces bronchodilation in asthmatic individuals during both short- and longer-term bouts up to 20 minutes. This result in longer-term isocapnic hyperpnoea apparently deviates from the response of asthmatic individuals to the hyperpnoea of longer-term dynamic exercise raising interesting questions. Voluntary hyperpnoea is important to this discussion as this technique is often used to assess the prevalence of exercise-induced asthma. While much is yet to be understood, dynamic, and possibly isometric, exercise is a powerful bronchodilator, at least over a short period of up to 15 minutes. It remains to be determined how airways respond to dynamic exercise of >15 minutes in both normal and asthmatic individuals and the mechanisms operating in the various circumstances. Additionally, attention to resting pulmonary function in asthmatic individuals must be given as those with constricted airways may differ in response to exercise, or to voluntary hyperpnoea, from those with normal airway function at rest.
Collapse
Affiliation(s)
- Robert W Gotshall
- Department of Health and Exercise Science, Colorado State University, Fort Collins, 80523, USA.
| |
Collapse
|
32
|
Descatha A, Fromageot C, Ameille J, Lejaille M, Falaize L, Louis A, Lofaso F. Is forced oscillation technique useful in the diagnosis of occupational asthma? J Occup Environ Med 2006; 47:847-53. [PMID: 16093935 DOI: 10.1097/01.jom.0000169092.61814.0c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE The aim of the study was to determine whether the forced oscillation technique (FOT), which does not require active cooperation, may be useful to assess bronchial responsiveness in patients with suspected occupational asthma (OA). METHODS Changes in resistances evaluated by FOT, and DeltaFEV1 measured during methacholine challenge test were compared in 77 adults referred for suspected OA. Spearman correlations and ROC curves were used. RESULTS R0 at the final dose of methacholine (R0hmd) and DeltaR0 were strongly correlated with DeltaFEV1 (p < 0.001). The ROC curves showed that R0hmd >or= 240% predicted was the best cut-off value to discriminate subjects with OA from nonasthmatic subjects (sensitivity: 80%, specificity: 76%). CONCLUSION FOT can be proposed as an alternative method for the assessment of bronchial responsiveness in subjects with suspected OA, unable to correctly perform forced expiratory maneuvers.
Collapse
Affiliation(s)
- Alexis Descatha
- Unité de pathologie professionnelle et de santé au travail, Hôpital Raymond Poincaré, Garches, France.
| | | | | | | | | | | | | |
Collapse
|
33
|
Thomas MR, Rafferty GF, Blowes R, Peacock JL, Marlow N, Calvert S, Milner A, Greenough A. Plethysmograph and interrupter resistance measurements in prematurely born young children. Arch Dis Child Fetal Neonatal Ed 2006; 91:F193-6. [PMID: 16239293 PMCID: PMC2672703 DOI: 10.1136/adc.2005.079608] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Airways obstruction in premature infants is often assessed by plethysmography, which requires sedation. The interrupter (Rint) technique does not require sedation, but has rarely been examined in children under 2 years of age. OBJECTIVE To compare Rint results with plethysmographic measurements of airway resistance (Raw) in prematurely born, young children. DESIGN Prospective study. SETTING Infant and Paediatric Lung Function Laboratories. PATIENTS Thirty children with a median gestational age of 25-29 weeks and median postnatal age of 13 months. INTERVENTIONS AND MAIN OUTCOME MEASURES The infants were sedated, airway resistance was measured by total body plethysmography (Raw), and Rint measurements were made using a MicroRint device. Further Raw and Rint measurements were made after salbutamol administration if the children remained asleep. RESULTS Baseline measurements of Raw and Rint were obtained from 30 and 26 respectively of the children. Mean baseline Rint values were higher than mean baseline Raw results (3.45 v 2.84 kPa/l/s, p = 0.006). Limits of agreement for the mean difference between Rint and Raw were -1.52 to 2.74 kPa/l/s. Ten infants received salbutamol, after which the mean Rint result was 3.6 kPa/l/s and mean Raw was 3.1 kPa/l/s (limits of agreement -0.28 to 1.44 kPa/l/s). CONCLUSION The poor agreement between Rint and Raw results suggests that Rint measurements cannot substitute for plethysmographic measurements in sedated prematurely born infants.
Collapse
Affiliation(s)
- M R Thomas
- Department of Child Health, 4th Floor Golden Jubilee Wing, King's College Hospital, Bessemer Road, London SE5 9RS, UK
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Evans TM, Rundell KW, Beck KC, Levine AM, Baumann JM. Airway Narrowing Measured by Spirometry and Impulse Oscillometry Following Room Temperature and Cold Temperature Exercise. Chest 2005; 128:2412-9. [PMID: 16236903 DOI: 10.1378/chest.128.4.2412] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVE The efficacy of using impulse oscillometry (IOS) as an indirect measure of airflow obstruction compared to spirometry after exercise challenges in the evaluation of exercise-induced bronchoconstriction (EIB) has not been fully appreciated. The objective was to compare airway responses following room temperature and cold temperature exercise challenges, and to compare whether IOS variables relate to spirometry variables. DESIGN Spirometry and IOS were performed at baseline and for 20 min after challenge at 5-min intervals. SETTING Two 6-min exercise challenges, inhaling either room temperature (22.0 degrees C) or cold temperature (- 1 degrees C) dry medical-grade bottled air. At least 48 h was observed between these randomly assigned challenges. PARTICIPANTS Twenty-two physically active individuals (12 women and 10 men) with probable EIB. INTERVENTIONS Subjects performed 6 min of stationary cycle ergometry while breathing either cold or room temperature medical-grade dry bottled air. Subjects were instructed to exercise at the highest intensity sustainable for the duration of the challenge. Heart rate and kilojoules of work performed were documented to verify exercise intensity. MEASUREMENTS AND RESULTS Strong correlations were observed within testing modalities for post-room temperature and post-cold temperature exercise spirometry and IOS values. Spirometry revealed no differences in postexercise peak falls in lung function between conditions; however, IOS identified significant differences in respiratory resistance (p < 0.05), with room temperature-inspired air being more potent than cold temperature-inspired air. CONCLUSIONS Correlations were found between spirometric and IOS measures of change in airway function for both exercise challenges, indicating close equivalency of the methods. The challenges appeared to elicit the EIB response by a similar mechanism of water loss, and cold temperature did not have an additive effect. IOS detected a difference in degree of response between the temperatures, whereas spirometry indicated no difference, suggesting that IOS is a more sensitive measure of change in airway function.
Collapse
Affiliation(s)
- Tina M Evans
- Marywood University, 2300 Adams Ave, Scranton, PA 18509, USA
| | | | | | | | | |
Collapse
|
35
|
Jain N, Covar RA, Gleason MC, Newell JD, Gelfand EW, Spahn JD. Quantitative computed tomography detects peripheral airway disease in asthmatic children. Pediatr Pulmonol 2005; 40:211-8. [PMID: 16015663 DOI: 10.1002/ppul.20215] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The aim of this study was to compare air-trapping as quantified by high-resolution computed tomography (HRCT) of the chest with measures of lung function and airway inflammation in children with mild to moderate asthma. Plethysmography indices, respiratory resistance, and reactance before and after bronchodilator with impulse oscillation (IOS), exhaled nitric oxide (eNO), total eosinophil count (TEC), and serum eosinophil cationic protein (ECP) levels were measured in 21 subjects. A single-cut HRCT image at end-expiration was obtained. Air-trapping was quantified and expressed in terms of the pixel index (PI) by determining the percentage of pixels in lung fields below -856 and -910 Hounsfeld units (HU). Pairwise linear correlations between PI and other parameters were evaluated. Subjects had only mild airflow limitation based on prebronchodilator forced expiratory volume in 1 sec (FEV(1)), but were hyperinflated and had air-trapping based on elevated total lung capacity (TLC) and residual volume (RV)/TLC ratio, respectively. The PI at -856 HU was positively correlated with % predicted TLC, total gas volume (TGV), and ECP level, and was inversely correlated with FEV(1)/forced vital capacity (FVC) and % predicted forced expiratory flow between 25-75% FVC (FEF(25-75)). The PI at -910 HU correlated similarly with these variables, and also correlated positively with IOS bronchodilator reversibility. This data suggest that quantitative HRCT may be a useful tool in the evaluation of peripheral airflow obstruction in children with asthma.
Collapse
Affiliation(s)
- Neal Jain
- Division of Allergy-Clinical Immunology, Department of Pediatrics, National Jewish Medical and Research Center and University of Colorado Health Sciences Center, Denver, Colorado 80206, USA
| | | | | | | | | | | |
Collapse
|
36
|
Kooi EMW, Vrijlandt EJLE, Boezen HM, Duiverman EJ. Children with smoking parents have a higher airway resistance measured by the interruption technique. Pediatr Pulmonol 2004; 38:419-24. [PMID: 15470684 DOI: 10.1002/ppul.20093] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Children exposed to environmental tobacco smoke, during or after pregnancy, are known to have decreased lung function. So far this has been measured using spirometry in schoolchildren and invasive techniques in newborns. The interruption technique (Rint) is a noninvasive technique to measure airway resistance in preschool children. Our aim in this study was to investigate the effect of passive smoke exposure on Rint values in preschool and school-aged children. Rint values were obtained from 557 children in two nursery and two primary schools in the north of the Netherlands. Besides information on parental smoking habits, we collected data on characteristics that might affect airway resistance (respiratory symptoms, atopy, and family history for asthma), using a short questionnaire. Multiple linear regression was used to estimate the associations of these characteristics with Rint, for the whole group as well as for the preschool group separately. Atopy or a positive family history for asthma did not affect Rint values in the total group of 4-12-year-olds. However, as may be expected, height, age, weight, and having respiratory symptoms were associated with Rint. Moreover, Rint was significantly increased if parents smoked three or more cigarettes a day in the presence of their child. This result remained after subgroup analysis in the preschool children (4-6 years old). We conclude that passive smoke exposure is associated with a significantly higher airway resistance in preschool and school-aged children measured by Rint.
Collapse
Affiliation(s)
- Elisabeth M W Kooi
- Department of Pediatric Pulmonology, Beatrix Children's Hospital, Groningen University Hospital, The Netherlands.
| | | | | | | |
Collapse
|
37
|
Boulé M. Explorations fonctionnelles respiratoires pédiatriques : (techniques et résultats selon l’âge). Arch Pediatr 2003; 10:932-7. [PMID: 14550987 DOI: 10.1016/s0929-693x(03)00416-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- M Boulé
- Unité de physiologie respiratoire du nourrisson, de l'enfant et de l'adolescent, hôpital Armand-Trousseau, France.
| |
Collapse
|
38
|
Marotta A, Klinnert MD, Price MR, Larsen GL, Liu AH. Impulse oscillometry provides an effective measure of lung dysfunction in 4-year-old children at risk for persistent asthma. J Allergy Clin Immunol 2003; 112:317-22. [PMID: 12897737 DOI: 10.1067/mai.2003.1627] [Citation(s) in RCA: 161] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Objective lung function measurements are routinely used to diagnose and manage asthma, but their utility for young children has not been defined. OBJECTIVE Bronchodilator responses were measured by means of impulse oscillometry (IOS) and compared with conventional spirometry to determine the value of lung function measures in 4-year-old asthma-prone children. METHODS The study participants were in the Childhood Asthma Prevention Study (National Institute of Health/National Institute of Allergy and Infectious Diseases) and at risk for asthma. At age 4 years, concurrent asthma was determined by using a previously validated modified American Thoracic Society questionnaire. Children performed IOS and spirometry before and after albuterol administration and underwent skin prick testing to 13 common allergens to assess atopy. IOS measures were as follows: airways resistance at 5 Hz and 10 Hz, airways reactance at 5 Hz and 10 Hz, and resonant frequency. RESULTS Asthmatic patients versus nonasthmatic patients significantly differed in their IOS-assessed bronchodilator responses through Delta resistance at 5 Hz (medians, 27% vs 17%; P =.02) and Delta resistance at 10 Hz (24% vs 16%; P =.03). Because atopic children who have frequent wheezing are at risk for persistent asthma, the data were analyzed in regard to atopic patients with or without asthma. IOS strongly distinguished atopic asthmatic children through Delta resistance at 5 Hz (36% vs 13%, P =.007), Delta resistance at 10 Hz (25% vs 11%, P =.02), and Delta reactance at 10 Hz (47% vs 12%, P =.03). Conventional spirometry did not establish similar statistically significant findings. CONCLUSION IOS bronchodilator responses are remarkably abnormal in 4-year-old children, who are most likely to have persistent asthma. IOS is a useful diagnostic tool in early asthma development and might be a helpful objective outcome measure of early interventions.
Collapse
Affiliation(s)
- Alex Marotta
- Division of Pediatric Allergy and Immunology, National Jewish Medical and Research Center, and the Department of Pediatrics, University of Colorado Health Sciences Center, Denver, 80206, USA
| | | | | | | | | |
Collapse
|
39
|
Affiliation(s)
- Martin J Tobin
- Division of Pulmonary and Critical Care Medicine, Hines Veterans Affairs Hospital, Route 11N, Hines, Illinois 60141, USA.
| |
Collapse
|