• Tuberculosis and Respiratory Diseases
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• v.84 no.4
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• pp.274-281
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• 2021

Background: The Korea National Health and Nutrition Examination Survey (KNHANES) is a well-designed survey to collect national data, which many researchers have used for their studies. In KNHANES, although portable spirometry was used, its reliability has not been verified. Methods: We prospectively enrolled 58 participants from four Korean institutions. The participants were classified into normal pattern, obstructive pattern, and restrictive pattern groups according to their previous spirometry results. Lung function was estimated by conventional spirometry and portable spirometry, and the results were compared. Results: The intraclass correlation coefficients of forced vital capacity (FVC) (coefficient, 9.993; 95% confidence interval [CI], 0.988-0.996), forced expiratory volume in 1 second (FEV₁) (coefficient, 0.997; 95% CI, 0.995-0.998), FEV₁/FVC ratio (coefficient, 0.995; 95% CI, 0.992-0.997), and forced expiratory flow at 25-75% (FEF25-75%; coefficient, 0.991; 95% CI, 0.984-0.994) were excellent (all p<0.001). In the subgroup analysis, the results of the three parameters were similar in all groups. In the overall and subgroup analyses, Pearson's correlation of all the parameters was also excellent in the total (coefficient, 0.986-0.994; p<0.001) and subgroup analyses (coefficient, 0.915-0.995; p<0.001). In the paired t-test, FVC, FEV₁/FVC, and FEF25-75% estimated by the two instruments were statistically different. However, FEV₁ was not significantly different. Conclusion: Lung function estimated by portable spirometry was well-correlated with that estimated by conventional spirometry. Although the values had minimal differences between them, we suggest that the spirometry results from the KNHANES are reliable.

• Tuberculosis and Respiratory Diseases
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• v.51 no.3
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• pp.248-259
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• 2001

Background : In diagnosis or monitor of the airway obstruction in bronchial asthma, the measurement of $FEV_1$ in the standard method because of its reproducibility and accuracy. But the measurement of peak expiratory flow(PEF) by peak flow meter is much simpler and easier than that of $FEV_1$ especially in children. Yet there have been still no data of the predicted normal values of PEF measured by peak flow meter in Korean children. This study was conducted to provide equations to predict the normal value of PEF and correlation between PEF and $FEV_1$ in healthy children. Method : PEF was measured by MiniWright peak flow meter, and the forced expiratory volume and the maximum expiratory flow volume curves were measured by Microspiro HI 501(Chest Co.) in 346 healthy children(age:5-16 years, 194 boys and 152 girls) without any respiratory symptoms during 2 weeks before the study. The regression equations for various ventilatory parameters according to age and/or height, and the regression equations of $FEV_1$ by PEF were derived. Results : 1. The regression equation for PEF(L/min) was: $12.6{\times}$age(year)+$3.4{\times}$height(cm)-263($R^2=0.85$) in boys, and $6{\times}$age(year)+$3.9{\times}$height(cm)-293($R^2=0.82$) in girls. 2. The value of FEFmax(L/sec) derived from the maximum expiratory flow volume curves was multiplied by 60 to compare with PEF(L/min), and PEF was faster by 125 L/min in boys and 118 L/min in girls, respectively. 3. The regression equation for $FEV_1$(ml) by PEF(L/min) was:$7{\times}$PEF-550($R^2=0.82$) in boys, and $5.8{\times}$PEF-146 ($R^2=0.81$) in girls, respectively. Conclusion : This study provides regression equations predicting the normal values of PEF by age and/or height in children. And the equations for $FEV_1$, a gold standard of ventilatory function, was predicted by PEF. So, in taking care of children with airway obstruction, PEF measured by the peak flow meter can provide useful information.

• Journal of Korean Physical Therapy Science
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• v.19 no.4
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• pp.47-52
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• 2012

Purpose : The purpose of the study was to examine if a respiratory muscle strengthening training in patients with stroke can improve their pulmonary function. Methods : Volunteers were included for the study if a patient diagnosed stroke more than 6 months and had 24 points or higher in MMSE-K scores. Twenty-eight subjects participated in this study and were randomly divided into two groups; a breathing exercise group(n=14) and a control group(n=14). The intervention for all subjects was conducted for 20minutes, three times a week for 4 weeks. Subjects for the breathing exercise group had the respiratory muscle strengthening training using spiro-tigers, where-as subjects in the control group got their usual treatment ie a postural training. The six-minute walking test(6MWT) and the pulmonary function tests(FVC, $FEV_1$, $FEV_1$/FVC, VC, Vt, IRV and ERV) were employed to assess treatment effects at baseline and after their intervention. Results : Twenty-four subjects finished their 4-week treatment programs. The general characteristics between groups were found to be similar (p>0.05). The pulmonary function between groups were also observed no difference across groups at the baseline measurement (p>0.05). In the post treatment group comparison, subjects in the breathing exercise group showed an increase in lung function with VC ($2.73{\pm}0.80{\ell}$) and Vt ($0.87{\pm}0.38{\ell}$) than those in the control group ($1.91{\pm}0.80{\ell}$ and $0.48{\pm}0.22{\ell}$ respectively) (p<0.05). However, there was no difference found in 6MWT, FVC, $FEV_1$, $FEV_1$/FVC, IRV, and ERV across groups (p>0.05). Conclusion : A significant increase in VC and Vt was found in subjects with stroke, who had four-week training on respiratory muscle strengthening. However, respiratory muscle strengthening showed no effect on walking speed and FVC, $FEV_1$, $FEV_1$/FVC, IRV, and ERV in patients with stroke.

• Journal of Chest Surgery
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• v.33 no.3
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• pp.231-239
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• 2000

Background: This retrospective study tries to identify specific risk factors that may increase complication rates after the surgical treatment of tuberculous destroyed lung. Material and method: A retrospective study was performed on forty-seven patients, who received surgical treatment for tuberculous destroyed lung in the Department of Thoracic and Cardiovascular Surgery at Hanyang University Hospital from 1988 to 1998, to identify specific preoperative risk factors related to postoperative complications. Fisher's exact test was used to identify the correlations between the complications and right pneumonectomy, preoperative FEV1, predicted postoperative FEV1, massive hemoptysis, postoperative persistent empyema. Result: Hospital mortality and morbidity rates of the patients who received surgical treatment for tuberculous destroyed lung were 6.4% and 29.7%, respectively. In view of the hospital mortality and morbidity rates as a whole, predicted postoperative FEV1 less than 0.8L(p<0.005), preoperative FEV1 less than 1.8L(p=0.01), massive hemoptysis(p<0.005), postoperative persistent positive sputum cultures(p<0.0005), and the presence of multi drug resistant tuberculosis(p<0.05) presented statistically significant correlations. Among the postoperative complications, bronchopleural fistula, the most common complication, was found to have statistically significant corrleations with the preoperative empyema(p<0.05) and postoperative persistent positive sputum cultures(p<0.05). Conclusion: Although mortality and morbidity rates after surgical treatment of tuberculous destroyed lung were relatively low, when predicted postoperative FEV1 was less than 0.8L, when preoperative FEV1 was less than 1.8L, when massive hemoptysis was present, when postoperative sputum cultures were persistently positive, and when multi drug resistant tuberculosis was present, the rates were significantly higher.

• Journal of Preventive Medicine and Public Health
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• v.19 no.2 s.20
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• pp.314-321
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• 1986

Forced vital capacities (FVC's) and forced expiratory volumes in one second $(FEV_{1.0}'s)$ of 26 pneumoconiosis patients were checked at admission and were followed up for 10 months through hospitalization. FVC's and $FEV_{1.0}'s$ were slightly improved in 10 months after admission. The improvement of FVC's was statistically significant. In the group of large opacities in chest radiographs, FVC's and $FEV_{1.0}'s$ were lower than those values in small opacity group at admission but improved more progressively. Similar finding was noted in the group of emphysema; those values were lower at admission but improved more progressively than those of non-emphysema group.

• Journal of Preventive Medicine and Public Health
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• v.22 no.1 s.25
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• pp.25-28
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• 1989

Sixty-two medical records of patients with coal workers' pneumoconiosis who died in hospital as coal workers' pneumoconiosis were analysed for study of the relationship between forced expiratory volume in one second ($FEV_1$) and life expectancy in coal workers'pneumoconiosis. In the group who died of asphyxia from hemoptysis, life expectancy were well fitted with $FEV_1$(p<0.05). But others were not well fitted to simple linear regression equation. The prevalence of ECG sign of col pulmonale was more in the group of cardiorespiratory failure than asphyxia group. So, in the case of far advanced cor pulmonale, it was difficult to predict life expectancy by simple linear regression equation

• Journal of Chest Surgery
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• v.18 no.3
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• pp.517-528
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• 1985

Pulmonary function studies today are generally accepted as an integral part of the evaluation of poor-risk patients who are to have pulmonary surgery. The effect of various pulmonary surgery on lung function was investigated in 54 patients in whom comprehensive lung function test were performed before and between 2 months and 14 months after operation at the Department of Thoracic Surgery, Seoul National University Hospital. According to the result of analysis, the effect of pulmonary resection on forced flow rate was keeping with the change of lung volume, and the preoperative level of ventilatory function plays a major role in determining postoperative loss of functioning lung. Although all measures of expiratory flow [FVC, FEV1, FEFO.2-1.2, MEF50, FEF25-75] have the same percentage of reproducibility, but FEV1 shows most sensitive, reliable linear correlation with the functioning pulmonary tissue loss than other parameters. The linear regression lines derived from the correlation between preoperative [X] and postoperative [Y] FEV1 on various surgical procedures were as follows: 1. Y = 0.57X 0.03. in pneumonectomy group of lung cancer[r=0.84]. 2. Y = 0.56X + 0.33. in lobectomy group of lung cancer[r=0.79]. 3. Y = 0.69X + 0.25. in lobectomy group of pulmonary infection[r=0.91].

• The Journal of Korean Physical Therapy
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• v.32 no.1
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• pp.34-38
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• 2020

Purpose: The purpose of this study was to identify the effects of the types of seat surface (static or dynamic seat surface) on the pulmonary functions during prolonged sitting. Methods: Thirty-four participants (20 males and 14 females) were recruited, and distributed randomly into dynamic prolonged sitting (DPS, n=17) and static prolonged sitting (SPS, n=17) groups. The DPS group was seated on a chair with a dynamic air cushion, and the SPS group was seated on a chair without a dynamic air cushion. The pulmonary function was assessed before sitting, and after participants had been seated for one hour. The pulmonary function [forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and Peak expiratory flow (PEF)] was measured using a spirometer. Results: Statistical analyses revealed significant differences in the time x group interactions of FVC, FEV1, PEF, and FEV1/FVC. The DPS group were significantly different in FVC, FEV1, PEF, and FEV1/FVC after prolonged sitting for one hour, compared to the SPS group (p<0.05). Conclusion: These findings suggest that dynamic sitting can prevent a decrease in the physiological function, such as pulmonary functions, rather than static sitting during prolonged sitting.

• Tuberculosis and Respiratory Diseases
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• v.71 no.3
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• pp.188-194
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• 2011

Background: When patients with chronic respiratory symptoms have a normal spirometry result, it is not always easy to consider bronchial asthma as the preferential diagnosis. Forced expiratory flow between 25% and 75% of vital capacity ($FEF_{25{\sim}75%}$) is known as a useful diagnostic value of small airway diseases. However, it is not commonly used, because of its high individual variability. We evaluated the pattern of bronchodilator responsiveness (BDR) and the correlation between $FEF_{25{\sim}75%}$ and BDR in patients with suspicious asthma and normal spirometry. Methods: Among patients with suspicious bronchial asthma, 440 adult patients with a normal spirometry result (forced expiratory volume in one second [$FEV_1$]/forced vital capacity [FVC] ${\geq}70%$ & $FEV_1%$ predicted ${\geq}80%$) were enrolled. We divided this group into a positive BDR group (n=43) and negative BDR group (n=397), based on the result of BDR. A comparison was carried out of spirometric parameters with % change of $FEV_1$ after bronchodilator (${\Delta}FEV_1%$). Results: Among the 440 patients with normal spirometry, $FEF_{25{\sim}75%}%$ predicted were negatively correlated with ${\Delta}FEV_1%$ (r=-0.22, p<0.01), and BDR was positive in 43 patients (9.78%). The means of $FEF_{25{\sim}75%}%$ predicted were $64.0{\pm}14.5%$ in the BDR (+) group and $72.9{\pm}20.8%$ in the BDR (-) group (p<0.01). The negative correlation between $FEF_{25{\sim}75%}%$ predicted and ${\Delta}FEV_1%$ was stronger in the BDR (+) group (r=-0.38, p=0.01) than in the BDR (-) group (r=-0.17, p<0.01). In the ROC curve analysis, $FEF_{25{\sim}75%}$ at 75% of predicted value had 88.3% sensitivity and 40.3% specificity for detecting a positive BDR. Conclusion: BDR (+) was not rare in patients with suspicious asthma and normal spirometry. In these patients, $FEF_{25{\sim}75%}%$ predicted was well correlated with BDR.

• Tuberculosis and Respiratory Diseases
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• v.62 no.4
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• pp.276-283
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• 2007

Background: A national health care initiative recommends routine spirometry screening of all smokers over age 45 or patients with respiratory symptoms. In response to the recommendation, new, simple, and inexpensive desktop spirometers for the purpose of promoting widespread spirometric screening were marketed. The performance of these spirometers was evaluated in vivo testing with healthy subjects. However, the clinical setting allows spirometric assessment of various pathologic combinations of flow and volume. Objective: The aim of this study was to compare the accuracy of a desktop spirometer to a standard laboratory spirometer, in a clinical setting with pathologic pulmonary function. Method: In a health check-up center, where screening pulmonary funct test was performed using the HI-801 spirometer. Subjects who revealed the ventilation defect in screening spirometry, performed the spirometry again using the standard Vmax spectra 22d spirometer in a tertiary care hospital pulmonary function laboratory. Pulmonary function test with both spirometer was performed according to the guidelines of the American Thoracic Society. Results: 109 patients were enrolled. Pulmonary function measurements (FVC, $FEV_1$, PEFR, FEF25%-75%) from the HI-801 correlated closely (r=0.94, 0.93, 0.81, 0.84, respectively) with those performed with the Vmax spectra 22d and showed the good limits of agreement and differences between the 2 devices; FVC +0.35 L, $FEV_1$ +0.16 L, PEFR +1.85 L/s, FEF25%-75%-0.13 L/s. With the exception of $FEV_1$, FEF25%-75%, these differences were significant(p<0.05) but small. Conclusion: The HI-801 spirometer is comparable to the standard laboratory spirometer, Vmax spectra 22d, with high accurary for $FEV_1$ and FVC and acceptable differences for clinical use.