PURPOSE: To evaluate on the basis of the pulmonary function test the correlation between the extent of air trapping on HRCT with the severity of airway obstruction and also to identify the prognostic effect of the extent of air trapping after treatment of asthma. MATERIALS AND METHODS: Thirty five patients with clinically diagnosed bronchial asthma and air trapping, as seen on HRCT, were included in this study. We quantitatively analysed on HRCT the extent of air trapping and then statistically compared this with the clinical parameters of the pulmonary function test. We classified the patients into two groups on the basis of the pulmonary function test and clinical status : Group 1(N=35), the total number of asthmatic patients ; Group 2(N=18), relatively stable asthmatics without acute asthmatic attack who showed FEV1 of more than 80% of the predicted value. Using the functional parameters of PEFR, one of the objective indications of improvement in airway obstruction, we also classified the patients into three groups on the basis of interval between treatment and clinical improvement. The result of this was as follows ; group 1, asymptomatic group(initial PEFR within normal limit, N=7) ; group 2, early responder(improvement of PEFR within three hospital days, N=18) ; group 3, late responder(improvement of PEFRwithin fourteen hospital days should there be a number here). Using HRCT, we then statistically analysed the differences between the three groups in the extent of air trapping. RESULTS: Among the total of 35 asthmatics, the extent of air trapping on HRCT showed significant correlation with the FEV1(r=-0.6161, p<0.001) and MEFR(r=-0.6012, p<0.001). Among the relatively stable asthmatics who showed FEV1 of more than 80% of the predicted value, MEFR(r=-0.7553, p<0.001) and FEF75(r=-0.7529, p=0.012) showed statistically significant correlation with the extent of air trapping on HRCT, but there was no significant corrlation between air trapping on HRCT and FEV1. In the three groups of asthmatics classified on the basis of interval between treatment and clinical improvement, the extents of air trapping on HRCT in the asymptomatic, early responder and late responder groups was as follows: (mean valuse) 9.31%, 21.50% and 27.89%, respectively ; these differences were statistically significant. CONCLUSION: The extent of air trapping on HRCT in asthmatics showed positive correlation with FEV1 and MEFR. Quantitative analysis of air trapping on HRCT also provides prognostic information about a patient's response to treatment.
Airway Obstruction ; Asthma ; Humans ; Maximal Expiratory Flow Rate ; Peak Expiratory Flow Rate ; Respiratory Function Tests*

OBJECTIVEDry powder inhalers (DPIs) are increasingly being used to deliver drugs for the treatment of asthma. It is known that DPIs require a crucial minimal inspiratory flow. Previous studies have demonstrated that the peak inspiratory flow (PIF, L/min) through a DPI is dependent on the type of device, the age of the patient, and the level of bronchial obstruction. However, the peak inspiratory flow of healthy preschool children in China remains scant in the literature. The present study aimed to analyze the ability of inspiring flow through the resistance state of ordinary use inhaler in Shenzhen healthy preschool children by measuring the peak inspiratory flow through the different analogue dry powder inhalers and go further into the relationship between it and the age, weight and forced expiratory volume of the children.

METHODA survey in 370 healthy preschool children aged 3 to 6 years (75 children aged 3 years, 104 children aged 4 years, 100 children aged 5 years and 91 children aged 6 years) was carried out in Shenzhen. Peak inspiratory flow (PIF) was measured without and with resistances, which mimicked the internal resistances of several inhalers, Diskus, Turbuhaler, Autohaler, Surehaler by PIF meter (In-check DIAL) and then data PIF-N, PIF-D, PIF-T, PIF-A and PIF-S were obtained. Peak expiratory flow (PEF) was measured by PEF meter (MicroPeak, USA). These two measurements were made in a well-controlled setting, and at least three attempts were recorded to establish maximum achievement. Six spirometry parameters forced vital capacity (FVC), forced expiratory volume at 0.5 second (FEV 0.5), forced expiratory volume at 0.75 second (FEV 0.75), forced expiratory volume at one second (FEV1), maximal mid expiratory flow rate (FEF 25 - 75, PEF were measured by using COSMED spirometry of Italy and the FVC measurements should be around the quality control for spirometry in preschool children which we suggested and published in 2005. All data were expressed as mean +/- SD and analyzed with the statistical software SPSS 12.0 for Windows. Pearson's test was used for calculation of the significances of the correlation coefficients. Variance analysis was used for analysing the variability of inspiratory flows through the inhalers.

RESULTSResults were obtained from 295 children aged 3 - 6 years who successfully finished the tests. The PIF-N, PIF-D, PIF-T, PIF-A and PIF-S were significantly different among the groups aged 3 yrs, 4 yrs, 5 yrs and 6 yrs. The peak inspiratory flow significantly increased with age. The PIF-N, PIF-D, PIF-T, PIF-A and PIF-S in the children of 110 cm height and above were significantly higher than those in the children below 110 cm height, so were the parameters between the children of 120 cm height and above and the children below 120 cm. PIF correlated significantly with age, height and weight and the Pearson coefficient was 0.3 - 0.5. The PIFs in different inhalers varied because of the different inner resistances. The minimum and optimum PIFs in resistances of Diskus, Autohaler and Surehaler could be achieved in almost all subjects, but those in resistances of Turbuhaler could be achieved in only 87.5% subjects, most of whom aged 3 yrs or below 100 cm height. There were good correlations between the PIFs in different resistances and main parameters of ventilation function (FVC, FEV 0.5, FEV 0.75, FEV1, FEF 25 - 75, PEF), PEF was the best among them (Pearson correlative coefficient was 0.6).

CONCLUSIONThe inspiratory ability of the children can be predicted and assessed by using routine measurement of lung function of normal pre-school children. As to the pre-school children of varying ages, the variety of inspiratory ability should be considered completely in the selection of inhaler used during the treatment. The best inhaler suitable for them should be selected properly in order to obtain the best efficacy of treatment individually.

Child ; Child, Preschool ; China ; Female ; Humans ; Inspiratory Capacity ; Male ; Maximal Expiratory Flow Rate ; Metered Dose Inhalers

Small and large airways functions were studied in patients with hypertensive heart disease in slightly ro moderately compromised state functionally. In this study, the forced vital capacity and various flow paramaeters reflecting expiratory flow rate were determined from simultaneously recorded forced expiratory volume and maximal expiretory flow volume curves in 86 cases. The closing volume was measured by a single breath nitrogen mrthod in 57 cases and airway resistance with its related parameters by a body plethysmograph in 11 cases. These results were compared with those obtained from the same numbers of healthy controls matched for sex, age and height. In the patient group, the forced vital capadity and all the observed values of flow parameters, execpt for the ratio of the first second vital capacity to the forced vital capacity, were significantly reduced than those in the controls. When the remainder of flow parameters was volume-adjusted to the forced vital capacity, however, the mean of the peak expiratory flow rate and the maximal expiratory flow rate at the 75 percent of the vital capacity were not significantly different from that of controls. In contrast, the volume-adjusted values of maximal expiratory flow were remained significantly smaller than those in the controls. The closing volume and its ratio to the vital capacity were significantly larger in the patient group. Airway resistance and its related parameters revealed no significant differences between two groups. These findings suggest that the patients with hypertensive heart disease in a mild to moderate failure are associated with restrictive ventilatory impairment and a small airways obstruction, but with little or no large airway dysfunction.
Airway Resistance ; Closing Volume ; Forced Expiratory Volume ; Heart Diseases* ; Heart* ; Humans ; Maximal Expiratory Flow Rate ; Nitrogen ; Peak Expiratory Flow Rate ; Vital Capacity

In China there are 1,923,842 Korean Chinese, who live mostly (92.27%) in the country's three northeast provinces. In spite of this sizeable number, no spirometric data are available at present on them. The present study investigated normal spirometric reference values for the Korean Chinese children and adolescents. Spirometry was performed in 443 healthy Korean Chinese children and adolescents aged 8-18 yr with measurements of forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF) and maximum mid-expiratory flow (MMEF). Reference equations for FEV1, FVC, PEF and MMEF were derived by using multiple regression analysis. All of the measured spirometric parameters correlated positively with height and age significantly (P < 0.001). The predicted values of FVC and FEV1 were higher than values obtained by using Caucasian and other Asian equations (P < 0.001). A set of spirometric reference equations has been derived using a relatively large, healthy, non-smoking young Korean Chinese population with a wide range of ages and heights, the results of which differ from those gained from several other reference equations. These reference equations should be used for evaluation of lung function in this population.
Adolescent ; Child ; China ; Female ; *Forced Expiratory Volume ; Humans ; Lung/*physiology ; Male ; Maximal Expiratory Flow Rate ; Peak Expiratory Flow Rate ; Reference Values ; Republic of Korea/ethnology ; Spirometry/*standards ; *Vital Capacity

OBJECTIVETo investigate the expression of vitamin D3 upregulated protein-1 (VDUP1) in peripheral eosinophils at different stages of asthma and its correlation with clinical manifestations of asthma.

METHODSFourteen normal volunteers and 51 mild to moderate asthma patients, including 16 untreated patients with asthma attack and 35 with asthma remission by continuously corticosterone inhalation. The symptom severity and pulmonary function indices were evaluated and induced sputum eosinophil counts and blood eosinophil count measured. VDUP1 and beta-actin gene fragments were amplified simultaneously by RT-PCR from the total RNA of peripheral eosinophils, and 10 microl of the RT-PCR product underwent agarose gel electrophoresis and the VDUP1/beta-actin ratio was obtained by Gel-Pro software.

RESULTSVDUP1/beta-actin ratio significantly decreased in untreated patients with asthma attacks in comparison with normal volunteers (0.314+/-0.242 vs 0.532 +/-0.279) but not in patients with asthma remission (0.612+/-0.381). In the former patients, a positive correlation of VDUP1/beta-actin ratio was found with FEV1.0% (r=0.587, P=0.046) and %PEF (r=0.563, P=0.033), whereas an inverse one observed with sputum eosinophil count (r=-0.436, P=0.049).

CONCLUSIONVDUP1 expression in the eosinophils correlates to eosinophil activation and may influence the disease severity of asthma patients.

Actins ; biosynthesis ; genetics ; Asthma ; blood ; metabolism ; Carrier Proteins ; biosynthesis ; genetics ; Eosinophils ; metabolism ; Humans ; Maximal Expiratory Flow-Volume Curves ; Peak Expiratory Flow Rate ; Respiratory Function Tests ; Thioredoxins ; biosynthesis ; genetics

OBJECTIVETo investigate the association of forced expiratory volume in 1 second (FEV1) and the maximum peak expiratory flow (PEF) with small airway function in asthmatic children of different ages and genders.

METHODSThis cross-sectional study was conducted among 619 asthmatic children with disease remission aged 3 to 13 years. The children were divided into 3 age groups, namely 3 to 5 years group (314 cases), 6 to 9 years group (207 cases) and 10 to 13 years group (98 cases), and their respiratory physiological parameters such as FEV1 and PEF were measured.

RESULTSOf the airway function parameters, PEF showed the highest abnormality rate (>85%) in these asthmatic children. In male and female asthmatic children aged 6 to 9 years, abnormalities in forced expiratory flow rate 25% (MEF25) showed the highest frequency (56% and 63%, respectively). In 3-5 years and 10-13 years groups, MEF25 abnormalities were the most frequent in male children (43% and 71%, respectively), whereas abnormalities in MEF50 were the most common in female children (33% and 69%, respectively). FEV1 and PEF were positively correlated to all the parameters of small airway functions in these asthmatic children (r>0.5, P<0.01) except for MEF25 in female asthmatic children aged 3 to 5 years (r=0.19, P=0.168; r=0.086, P=0.535).

CONCLUSIONIn asthmatic children, FEV1 and PEF are positively correlated to the parameters of small airway function with only the exception of MEF25 in female children aged 3 to 5 years, suggesting the value of FEV1 in the diagnosis of asthma in children.

Adolescent ; Asthma ; diagnosis ; physiopathology ; Bronchi ; physiopathology ; Child ; Child, Preschool ; Cross-Sectional Studies ; Female ; Forced Expiratory Volume ; physiology ; Humans ; Male ; Maximal Expiratory Flow Rate ; physiology ; Respiratory Function Tests

PURPOSE: To evaluate the HRCT findings of hypersensitive pneumonitis and to correlate the findings with the results of the pulmonary function test (PFT). MATERIALS AND METHODS: Seven patients in whom hypersensitive pneumonitis was histologically confirmed (by transbronchial lung biopsy in two, thoracoscopic lung biopsy in one, open lung biopsy in two, and typical clinical and laboratory findings in two) were involved in this study. Their radiological patterns were assessed by HRCT and the extent of each finding was evaluated semi-quantitatively and correlated with the results of the pulmonary function test. RESULTS: The HRCT findings were as follows: lobular overinflation (n = 7), ground glass attenuation (n = 7), centrilobular nodule (n = 6), reticular opacity (n = 5), interlobular septal thickening (n = 3), consolidation (n = 2), and irregular subpleural line (n = 1). Five patients showed lower lung predominance and two, middle lung predominance. In all, a restrictive pattern and diminished diffusion capacity was noted. The grade score of reticular opacity showed significant correlation with forced vital capacity and forced expiratory volume. There was, however, no significant correlation between other HRCT findings and PFT results. Two patientsin whom lobular overinflation associated with parenchymal fibrosis was noted showed a decreased maximal midexpiratory flow rate of 25 -75. CONCLUSION: Lobular overinflation, ground-glass attenuation and centrilobular nodules are commonly observed in hypersensitive pneumonitis. The only significant correlation between each HRCT finding and the pulmonary function test was that between reticular opacity and both forced expiratory volume and forced vital capacity. In cases of chronic hypersensitive pneumonitis presenting as pulmonary fibrosis, associated lobular overinflation could be helpful for differential diagnosis.
Alveolitis, Extrinsic Allergic* ; Biopsy ; Diagnosis, Differential ; Diffusion ; Fibrosis ; Forced Expiratory Volume ; Glass ; Humans ; Hypersensitivity* ; Lung ; Maximal Midexpiratory Flow Rate ; Pneumonia ; Pulmonary Fibrosis ; Respiratory Function Tests* ; Vital Capacity

OBJECTIVEImpulse oscillation system (IOS) as an approach to lung function determination is suitable for children, especially for preschool children in that it only requires the individual to be examined to breathing stably with tidal volume. However, until now there have been no uniformly agreed criteria for positive bronchial reversibility test in clinical practice. A screening method was applied to seek for answer when this question in the hope of providing objective evidence for clinical diagnosis of respiratory diseases, esp. asthma.

METHODSOne hundred and fifty-six children patients during asthma attack were recruited randomly for this study from January to December, 2004. These patients included 103 boys and 53 girls aged from 5 to 18 years with mean age of 8.84 +/- 2.58 years, who visited the doctors in the Clinical and Educational Centre for Asthma, Capital Institute of Pediatrics and were diagnosed as asthma. Maximal expiratory flow volume and IOS lung function were determined followed by bronchodilator reversibility test in all patients. The sensitivity and specificity of IOS parameters, total respiratory impedance (Zrs), respiratory resistance at 5 Hz (R5) and reactance at 5 Hz (X5) for diagnosing asthma at different improvement levels after inhalation of bronchodilator were calculated respectively using forced expiratory volume in first second (FEV(1)) and maximal mid-expiratory flow (MMEF) as gold standard. And the regression equation between parameters of lung function which were determined with the two different methods was analyzed.

RESULTSAfter inhalation of bronchodilator, the lung function of the children was improved significantly (P < 0.01), with the FEV(1), MMEF increase and Zrs, R5, and X5 decrease. There were significantly positive correlations (P < 0.01) between the improvement rate of parameters of lung functions determined with the two methods, and the highest correlation coefficients existed between X5 and FEV(1) and MMEF (respectively 0.676, 0.571), correlation coefficients between X5 and Zrs ranked second (0.519 and 0.505, respectively). When an increase of FEV(1) equal to or greater than 15%, or increase of MMEF equal to or greater than 30% was used as reference for positive bronchial reversibility, the sensitivity and specificity were relatively high for considering positive bronchial reversibility test with at least 20% decrease of Zrs, R5, and 30% decrease of X5 with IOS lung function. The sensitivity and specificity of Zrs, R5 and X5 calculated from FEV(1) were 0.62, 0.51; 0.49, 0.54; 0.70, and 0.54, respectively. The sensitivity and specificity of Zrs, R5 and X5 calculated from MMEF were 0.63, 0.54; 0.53, 0.60; 0.60, and 0.58, respectively. The regression equation showed that the decrease of Zrs, R5 and X5 corresponding to 15% increase of FEV(1) and 30% increase of MMEF were 21.7%, 21.3%; 19.9%, 19.5%; 30.1%, and 29.6%, respectively.

CONCLUSIONWhen lung function is determined with IOS in children, only when decrease of Zrs and R5 is equal to or more than 20% and decrease of X5 is 30% or more after inhalation of bronchodilator, can the bronchial reversibility test be considered as positive.

Adolescent ; Asthma ; diagnosis ; Bronchodilator Agents ; administration & dosage ; Child ; Child, Preschool ; Female ; Forced Expiratory Volume ; Humans ; Male ; Maximal Midexpiratory Flow Rate ; Regression Analysis ; Respiratory Function Tests ; methods ; Sensitivity and Specificity

OBJECTIVETo investigate the changes of pulmonary function and fractional exhaled nitric oxide (FeNO) in the standardized treatment of bronchial asthma in children.

METHODSA total of 254 children who were newly diagnosed with acute exacerbation of bronchial asthma were selected as asthma group, and they were divided into two subgroups: asthma with concurrent rhinitis and asthma without concurrent rhinitis. All patients received the standardized management and treatment for one year. The pulmonary function parameters included forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), maximal mid-expiratory flow (MMEF), and mid-expiratory flow at 25%, 50%, and 75% of vital capacity (MEF25, MEF50, and MEF75). The FeNO levels were measured before treatment and at 3, 6, 9, and 12 months after treatment. Another 62 healthy children were selected as the control group, and the pulmonary function and FeNO levels were measured only once.

RESULTSDuring one year of standardized treatment, FEV1, PEF, MMEF, MEF25, MEF50, and MEF75 gradually increased, and FeNO levels gradually decreased (P<0.05). Indicators of large airway function, such as FEV1 and PEF, almost returned to normal after 6 months of treatment; indicators of small airway function, such as MMEF, MEF25, MEF50, and MEF75 almost returned to normal after 9 months of treatment; there were no significant differences in the above indices between the asthma group and the control group after one year of treatment (P>0.05). However, the asthma group had a significantly higher FeNO levels than the control group after one year of treatment (P<0.05). The asthmatic patients with concurrent rhinitis had significantly higher FeNO levels than those without concurrent rhinitis before treatment and 3 months after treatment (P<0.05). Before treatment, there was a significant negative correlation between FeNO levels and pulmonary function parameters (P<0.05).

CONCLUSIONSWith the standardized treatment of bronchial asthma in children, pulmonary function parameters gradually increase and FeNO levels gradually decrease. The recovery of large airway function occurs earlier than the recovery of small airway function. Furthermore, the effect of rhinitis on airway responsiveness should be noted.

Asthma ; physiopathology ; therapy ; Breath Tests ; Child ; Female ; Forced Expiratory Volume ; Humans ; Lung ; physiopathology ; Male ; Maximal Midexpiratory Flow Rate ; Nitric Oxide ; analysis ; Rhinitis ; physiopathology

BACKGROUND: Maximal expiratory flow rate is determined by the size of airway, the elastic recoil pressure and the collapsibility of airway in the lung, and one of major functional impairments of emphysema, which represents COPD, is the obstruction of expiratory flow. Neverthless, expiratory narrowing of upper airway may be recruited as a mechanism for minimizing airway collapse, and maintaining lung volume and hyperinflation by an endogenous positive end-expiratory pressure in patients with airflow obstruction. We investigated the physiologic role of trachea in respiration in emphysema. METHOD: We collected 20 patients with emphysema (which was diagnosed by radiologic and physio logic criteria) from January to August in 1997 at Seoul Municipal Boramae Hospital, and chest roentgenogram, high resolution computed tomography(HRCT), and pulmonary function tests including arterial blood gas analysis and body plethysmography were done from each patient. Cross-sectional area of trachea was measured according to the respiratory cycle on the level of aortic arch by HRCT and calibrated with body surface area. We compared this calibrated area with such parameters of pulmonary function tests as PaCO2, PaO2, airway resistance, lung compliance and so on. RESULTS: Expiratory cross-sectional area of trachea has significant correlation with PaCO2 (r=-0.61, p<0.05), PaO2 (r=0.6, p<0.05), and minute ventilation (r=0.73, p<0.05), but inspiratory cross-sectional area doesn't (r=-0.22, p>0.05 with PaCO2, r=0.26, p>0.05 with PaO2, and r=0.44, p>0.05 with minute ventilation). Minute ventilation has significant correlation with tidal volume (r=0.45, p<0.05), but it doesn't have significant correlation with respiratory frequency (r=-0.31, p>0.05). Cross-sectional area of trachea doesn't have any significant correlation with other parameters of pulmonary function such as FEV1, FVC, FEV1/FVC, peak expiratory flow, residual volume, diffusing capacity, airway resistance, and lung compliance, whether the area is expiratory or inspiratory. CONCLUSION: Cross-sectional area of trachea narrowed during expiration in emphysema and its expiratory area has significant correlation with PaCO2, PaO2, and minute ventilation.
Airway Resistance ; Aorta, Thoracic ; Blood Gas Analysis ; Body Surface Area ; Emphysema ; Humans ; Logic ; Lung ; Lung Compliance ; Maximal Expiratory Flow Rate ; Plethysmography ; Positive-Pressure Respiration ; Pulmonary Disease, Chronic Obstructive* ; Residual Volume ; Respiration ; Respiratory Function Tests* ; Seoul ; Thorax ; Tidal Volume ; Trachea ; Ventilation