Wheezing is one of the characteristic symptoms of asthma, but all preschool children with wheezing are not diagnosed with asthma. Preschool children are not cooperative enough to participate in spirometry and invasive tests. Thus, there is no conventional method to diagnose asthma in preschool children. We reviewed studies on non-invasive biomarkers for assessing asthma in preschool children. Specimens that can be easily obtained by non-invasive methods are blood, exhaled breath and urine. Eosinophils, eosinophil cationic protein and eosinophil-derived neurotoxin (EDN) in blood are helpful in evaluating eosinophilic inflammation of the airways. Exhaled breath contains nitric oxide, volatile organic compounds, various cytokines and mediators as analytical components. Fraction of exhaled nitric oxide has been used to assess the degree of eosinophil inflammation and has been standardized in school-age children and adults, but not yet in preschool children. Exhaled breath condensate (EBC) pH and various cytokines/mediators that are detected in EBC seem to be promising biomarkers for assessing asthma, but need more standardization and validation. There are several biomarkers useful for assessing asthma, but none are ideal. Some biomarkers need standardized methods of obtaining samples from uncooperative preschool children for clinical use and require sufficient validation. Recently, another activated eosinophil marker, serum EDN, has shown promising results as a biomarker for recurrent wheezing and asthma in preschool children.
Adult ; Asthma* ; Biomarkers* ; Child ; Child, Preschool* ; Cytokines ; Eosinophil Cationic Protein ; Eosinophil-Derived Neurotoxin ; Eosinophils ; Humans ; Hydrogen-Ion Concentration ; Inflammation ; Methods ; Nitric Oxide ; Respiratory Sounds* ; Spirometry ; Volatile Organic Compounds

Background: Neural respiratory drive (NRD) using diaphragm electromyography through an invasive transesophageal multi-electrode catheter can be used as a feasible clinical physiological parameter in patients with chronic obstructive pulmonary disease (COPD) to provide useful information on the treatment response. However, it remains unknown whether the surface diaphragm electromyogram (EMGdi) could be used to identify the deterioration of clinical symptoms and to predict the necessity of hospitalization in acute exacerbation of COPD (AECOPD) patients. Methods: COPD patients visiting the outpatient department due to acute exacerbation were enrolled in this study. All patients who were subjected to EMGdi and classical parameters such as spirometry parameters, arterial blood gas analysis, COPD assessment test (CAT) score, and the modified early warning score (MEWS) in outpatient department, would be treated effectively in the outpatient or inpatient settings according to the Global Initiative for Chronic Obstructive Lung Disease guideline. When the acute exacerbation of the patients was managed, all the examination above would be repeated. Results: We compared the relationships of admission-to-discharge changes (Δ) in the normalized value of the EMGdi, including the change of the percentage of maximal EMGdi (ΔEMGdi%max) and the change of the ratio of minute ventilation to the percentage of maximal EMGdi (ΔVE/EMGdi%max) with the changes of classical parameters. There was a significant positive association between ΔEMGdi%max and ΔCAT, ΔPaCO, and ΔpH. The change (Δ) of EMGdi%max was negatively correlated with ΔPaO/FiOin the course of the treatment of AECOPD. Compared with the classical parameters including forced expiratory volume in 1 s, MEWS, PaO/FiO, the EMGdi%max (odds ratio 1.143, 95% confidence interval 1.004-1.300) has a higher sensitivity when detecting the early exacerbation and enables to predict the admission of hospital in the whole cohort. Conclusions The changes of surface EMGdi parameters had a direct correlation with classical measures in the whole cohort of AECOPD. The measurement of NRD by surface EMGdi represents a practical physiological biomarker, which may be helpful in detecting patients who should be hospitalized timely.
Diaphragm ; physiopathology ; Electromyography ; methods ; Forced Expiratory Volume ; physiology ; Hospitalization ; Humans ; Pulmonary Disease, Chronic Obstructive ; metabolism ; physiopathology ; Spirometry ; Vital Capacity ; physiology

BACKGROUND: The present study aimed to update the prediction equations for spirometry and their lower limits of normal (LLN) by using the lambda, mu, sigma (LMS) method and to compare the outcomes with the values of previous spirometric reference equations. METHODS: Spirometric data of 10,249 healthy non-smokers (8,776 females) were extracted from the fourth and fifth versions of the Korea National Health and Nutrition Examination Survey (KNHANES IV, 2007–2009; V, 2010–2012). Reference equations were derived using the LMS method which allows modeling skewness (lambda [L]), mean (mu [M]), and coefficient of variation (sigma [S]). The outcome equations were compared with previous reference values. RESULTS: Prediction equations were presented in the following form: predicted value = e {a + b × ln(height) + c × ln(age) + M − spline}. The new predicted values for spirometry and their LLN derived using the LMS method were shown to more accurately reflect transitions in pulmonary function in young adults than previous prediction equations derived using conventional regression analysis in 2013. There were partial discrepancies between the new reference values and the reference values from the Global Lung Function Initiative in 2012. CONCLUSION: The results should be interpreted with caution for young adults and elderly males, particularly in terms of the LLN for forced expiratory volume in one second/forced vital capacity in elderly males. Serial spirometry follow-up, together with correlations with other clinical findings, should be emphasized in evaluating the pulmonary function of individuals. Future studies are needed to improve the accuracy of reference data and to develop continuous reference values for spirometry across all ages.
Adult ; Aged ; Follow-Up Studies ; Forced Expiratory Volume ; Humans ; Korea ; Lung ; Male ; Methods ; Nutrition Surveys ; Reference Values ; Spirometry ; Vital Capacity ; Young Adult

BackgroundThe interpretation of spirometry varies on different reference values. Older people are usually underrepresented in published predictive values. This study aimed at developing spirometric reference equations for elderly Chinese in Jinan aged 60-84 years and to compare them to previous equations.

MethodsThe project covered all of Jinan city, and the recruitment period lasted 9 months from January 1, 2017 to September 30, 2017, 434 healthy people aged 60-84 years who had never smoked (226 females and 208 males) were recruited to undergo spirometry. Vital capacity (VC), forced VC (FVC), forced expiratory volume in 1 s (FEV), FEV/FVC, FEV/VC, FEV, peak expiratory flow, and forced expiratory flow at 25%, 50%, 75%, and 25-75% of FVC exhaled (FEF, FEF, FEF, and FEF) were analyzed. Reference equations for mean and the lower limit of normal (LLN) were derived using the lambda-mu-sigma method. Comparisons between new and previous equations were performed by paired t-test.

ResultsNew reference equations were developed from the sample. The LLN of FEV/FVC, FEFcomputed using the 2012-Global Lung Function Initiative (GLI) and 2006-Hong Kong equations were both lower than the new equations. The biggest degree of difference for FEV/FVC was 19% (70.46% vs. 59.29%, t = 33.954, P < 0.01) and for maximal midexpiratory flow (MMEF, equals to FEF) was 22% (0.82 vs. 0.67, t = 21.303, P < 0.01). The 1990-North China and 2009-North China equations predicted higher mean values of FEV/FVC and FEFthan the present model. The biggest degrees of difference were -4% (78.31% vs. 81.27%, t = -85.359, P < 0.01) and -60% (2.11 vs. 4.68, t = -170.287, P < 0.01), respectively.

ConclusionsThe newly developed spirometric reference equations are applicable to elderly Chinese in Jinan. The 2012-GLI and 2006-Hong Kong equations may lead to missed diagnoses of obstructive ventilatory defects and the small airway dysfunction, while traditional linear equations for all ages may lead to overdiagnosis.

Aged ; Aged, 80 and over ; Cross-Sectional Studies ; Female ; Forced Expiratory Volume ; physiology ; Humans ; Male ; Middle Aged ; Reference Values ; Respiratory Function Tests ; Spirometry ; methods

The first national surveillance of COPD in mainland China was carried out in 2014, with the nationally representative data obtained. The national surveillance was significantly important for the monitoring of prevalence, risk factors, and changing trend of COPD among Chinese adults aged ≥ 40. The surveillance was also important in the development of national COPD prevention and control policy, the evaluation of prevention and control progress, the establishment of COPD comprehensive surveillance system, and the building of a professional COPD monitoring and prevention team. In this editorial, we briefly introduced the method and content of COPD surveillance, and reported the rate of spirometry examination and COPD awareness among adults aged ≥40 in China. We also analyzed the rate of main risk factors for COPD, such as tobacco smoking, occupational exposure to dust or chemical and indoor exposure to biomass or coal, and the distribution of high-risk population. This study provided fundamental data for the prevention and control of COPD in China.
Adult ; Aged ; Air Pollution, Indoor/statistics & numerical data* ; China/epidemiology* ; Chronic Disease/epidemiology* ; Dust ; Female ; Humans ; Male ; Occupational Exposure/statistics & numerical data* ; Population Surveillance/methods* ; Prevalence ; Pulmonary Disease, Chronic Obstructive/prevention & control* ; Risk Factors ; Smoking ; Spirometry ; Tobacco Smoke Pollution/statistics & numerical data*

Spirometry is a physiological test for assessing the functional aspect of the lungs using an objective indicator to measure the maximum amount of air that a patient can inhale and exhale. Acceptable spirometry testing needs to be conducted three times by an acceptable and reproducible method for determining forced vital capacity (FVC). Until the results of three tests meet the criteria of reproducibility, the test should be repeated up to eight times. Interpretation of spirometry should be clear, concise, and informative. Additionally, spirometry should guarantee optimal quality prior to the interpreting spirometry results. Our guideline adopts a fixed normal predictive value instead of the lower limit of normal as the reference value because fixed value is more convenient and also accepts FVC instead of vital capacity (VC) because measurement of VC using a spirometer is impossible. The bronchodilator test is a method for measuring the changes in lung capacity after inhaling a short-acting β-agonist that dilates the airway. When an obstructive ventilatory defect is observed, this test helps to diagnose and evaluate asthma and chronic obstructive pulmonary disease by measuring reversibility with the use of an inhaled bronchodilator. A positive response to a bronchodilator is generally defined as an increase of ≥12% and ≥200 mL as an absolute value compared with a baseline in either forced expiratory volume at 1 second or FVC.
Asthma ; Bronchodilator Agents ; Forced Expiratory Volume ; Humans ; Inhalation ; Lung ; Lung Volume Measurements ; Methods ; Pulmonary Disease, Chronic Obstructive ; Reference Values ; Spirometry* ; Vital Capacity

PURPOSE: High-sensitivity assays enabled the identification of C-reactive protein (hs-CRP) at levels that were previously undetectable. We aimed to determine if hs-CRP could reflect airway inflammation in children, by comparing hs-CRP with spirometry and impulse oscillometry (IOS) parameters and symptomatic severities. MATERIALS AND METHODS: A total of 276 asthmatic children who visited Severance Children's Hospital from 2012-2014 were enrolled. Serum hs-CRP and pulmonary function tests were performed on the same day. Patients were divided into hs-CRP positive and negative groups (cut-off value, 3.0 mg/L). RESULTS: Of the 276 asthmatic children [median age 7.5 (5.9/10.1) years, 171 boys (62%)], 39 were hs-CRP positive and 237 were negative. Regarding spirometry parameters, we observed significant differences in maximum mid-expiratory flow, % predicted (FEF25-75) (p=0.010) between hs-CRP positive and negative groups, and a negative correlation between FEF25-75 and hs-CRP. There were significant differences in the reactance area (AX) (p=0.046), difference between resistance at 5 Hz and 20 Hz (R5-R20) (p=0.027), resistance at 5 Hz, % predicted (R5) (p=0.027), and reactance at 5 Hz, % predicted (X5) (p=0.041) between hs-CRP positive and negative groups. There were significant positive correlations between hs-CRP and R5 (r=0.163, p=0.008), and X5 (r=0.164, p=0.007). Spirometry and IOS parameters had more relevance in patients with higher blood neutrophil levels in comparison to hs-CRP. CONCLUSION: Hs-CRP showed significant correlation with FEF25-75, R5, and X5. It can reflect small airway obstruction in childhood asthma, and it is more prominent in neutrophil dominant inflammation.
Airway Obstruction/*diagnosis/etiology ; Asthma/*diagnosis/physiopathology ; C-Reactive Protein/*analysis ; Child ; Child, Preschool ; Female ; Forced Expiratory Volume ; Humans ; Inflammation/*etiology ; Male ; Neutrophils/metabolism ; Oscillometry/*methods ; Respiratory Function Tests/*methods ; Respiratory System ; Sensitivity and Specificity ; *Spirometry

BACKGROUND: Surgical correction needs to be considered when diaphragm eventration leads to impaired ventilation and respiratory muscle fatigue. Plication to sufficiently tense the diaphragm by VATS is not as easy to achieve as plication by open surgery. We used pneumatic compression with carbon dioxide (CO2) gas in thoracoscopic diaphragmatic plication and evaluated feasibility and efficacy. METHODS: Eleven patients underwent thoracoscopic diaphragmatic plication between January 2008 and December 2013 in Pusan National University Hospital. Medical records were retrospectively reviewed, and compared between the group using CO₂ gas and group without using CO2 gas, for operative time, plication technique, duration of hospital stay, postoperative chest tube drainage, pulmonary spirometry, dyspnea score pre- and postoperation, and postoperative recurrence. RESULTS: The improvement of forced expiratory volume at 1 second in the group using CO₂ gas and the group not using CO₂ gas was 22.46±11.27 and 21.08±5.39 (p=0.84). The improvement of forced vital capacity 3 months after surgery was 16.74±10.18 (with CO₂) and 15.6±0.89 (without CO₂) (p=0.03). During follow-up (17±17 months), there was no dehiscence in plication site and relapse. No complications or hospital mortalities occurred. CONCLUSION: Thoracoscopic plication under single lung ventilation using CO₂ insufflation could be an effective, safe option to flatten the diaphragm.
Busan ; Carbon Dioxide* ; Carbon* ; Chest Tubes ; Diaphragm ; Diaphragmatic Eventration ; Drainage ; Dyspnea ; Fatigue ; Follow-Up Studies ; Forced Expiratory Volume ; Hospital Mortality ; Humans ; Insufflation ; Length of Stay ; Medical Records ; Methods ; One-Lung Ventilation ; Operative Time ; Recurrence ; Respiratory Muscles ; Retrospective Studies ; Spirometry ; Thoracic Surgery, Video-Assisted ; Thoracoscopy ; Transcutaneous Electric Nerve Stimulation ; Ventilation ; Vital Capacity

PURPOSE: The aim of this study was to investigate the effect of incentive spirometer exercise (ISE) on pulmonary function and maximal phonation time (MPT) in children with spastic cerebral palsy (CP). MATERIALS AND METHODS: Fifty children with CP were randomly assigned to two groups: the experimental group and the control group. Both groups underwent comprehensive rehabilitation therapy. The experimental group underwent additional ISE. The forced vital capacity (FVC), forced expiratory volume at one second (FEV1), FEV1/FVC ratio, peak expiratory flow (PEF), and MPT were assessed as outcome measures before and after 4 weeks of training. RESULTS: There were significant improvements in FVC, FEV1, PEF, and MPT in the experimental group, but not in the control group. In addition, the improvements in FVC, FEV1, and MPT were significantly greater in the experimental group than in the control group. CONCLUSION: The results of this randomized controlled study support the use of ISE for enhancing pulmonary function and breath control for speech production in children with CP.
Adolescent ; Body Fluids ; Breathing Exercises/*methods ; Cerebral Palsy/complications/*physiopathology ; Child ; *Exercise ; Female ; Forced Expiratory Volume ; Humans ; Lung ; Male ; Motivation ; *Spirometry ; Treatment Outcome

BACKGROUND: Lung age, calculated from sex, forced expiratory volume in one second (FEV1), and height, was developed to illustrate premature changes to the lungs and could be used to motivate smoking cessation. However, this method has not been tested in association with smoking in Korea. The purpose of this study was to investigate the association of lung age with smoking and other factors in Korean males. METHODS: We reviewed the records of 1,100 healthy men who visited a health promotion center at Ewha Womans University Medical Center from January 2008 to June 2009. Lung age was calculated from FEV1 and normal predictive values of spirometry according to age in the Korean population. The difference between lung age and chronological age was evaluated in relation to smoking status, weight, body mass index, waist, muscle mass, fat mass, and exercise. RESULTS: The age difference was significantly higher in current smokers than in non-smokers (12.47 +/- 19.90 vs. 7.30 +/- 19.52, P < 0.001). Additionally, the age difference was positively correlated with life time pack-year (beta = 0.223; P < 0.001) and fat mass (beta = 0.462; P < 0.001). Lung age increased 1 year for 4.48 pack-year increase or for 2.16% increase in fat mass. CONCLUSION: We found a significant relationship between lung age and both smoking status and fat mass in healthy Korean males. Lung age may be a useful tool for motivating cessation of cigarette smoking and management of risk factors related to obesity.
Academic Medical Centers ; Body Weight ; Female ; Forced Expiratory Volume ; Health Promotion ; Humans ; Korea ; Lung* ; Male ; Methods ; Muscles ; Obesity ; Risk Factors ; Smoke* ; Smoking Cessation ; Smoking* ; Spirometry