• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.628-635
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• 1999

Background : Maximal expiratory flow rate is determined by the size of airway, elastic recoil pressure and the collapsibility of airway in the lung. The obstruction of expiratory flow is one of the major functional impairments of emphysema, which represents COPD. Nevertheless, 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 included 20 patients diagnosed as emphysema by radiologic and physiologic criteria from January to August in 1997 at Seoul Municipal Boramae Hospital. Chest roentgenogram, high resolution computed tomography(HRCT), and pulmonary function tests including arterial blood gas analysis and body plethysmography were taken 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 corrected area with such parameters of pulmonary function tests as $PaCO_2$, $PaO_2$, airway resistance, lung compliance and so on. Results : Expiratory cross-sectional area of trachea had significant correlation with $PaCO_2$ (r=-0.61, p<0.05), $PaO_2$ (r=0.6, p<0.05), and minute ventilation (r=0.73, p<0.05), but inspiratory cross-sectional area did not (r=-0.22, p>0.05 with $PaCO_2$, r=0.26, p>0.05 with $PaO_2$, and r=0.44, p>0.05 with minute ventilation). Minute ventilation had significant correlation with tidal volume (r=0.45, p<0.05), but it had no significant correlation with respiratory frequency (r=-0.31, p>0.05). Cross-sectional area of trachea had no significant correlation with other parameters of pulmonary function including $FEV_1$, FVC, $FEV_1$/FVC, peak expiratory flow, residual volume, diffusing capacity, airway resistance, and lung compliance, whether the area was expiratory or inspiratory. Conclusion : Cross-sectional area of trachea narrowed during expiration in emphysema, and its expiratory area had significant correlation with $PaCO_2$, $PaO_2$, and minute ventilation.

• The Journal of Korean Physical Therapy
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• v.25 no.4
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• pp.204-209
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• 2013

Purpose: Children with cerebral palsy generally have a high incidence of respiratory problem, resulted from poor coughing, airway clearance problem, respiratory muscle weakness, kyphoscoliosis and so forth. The purpose of this study is to investigate the possible factors that can be affected to forced vital capacity (FVC) in children with cerebral palsy. Methods: Total thirty six children with diplegic and hemiplegic cerebral palsy were recruited in this study. They were evaluated by general demographic data (i.e., age, gender, body mass index (BMI)) and variables related to respiratory functions (i.e., chest mobility, waist mobility, maximal phonation time, and maximum inspiratory/expiratory pressure (MIP/MEP)). The correlation between forced vital capacity and the rested variables were analyzed, and multiple regression with stepwise method was conducted to predict respiratory function, in terms of FVC as the dependent variable, and demographic and other respiratory variables as the independent variable. Results: FVC showed a significant correlation with waist mobility (r=0.59, p<0.01), maximal phonation time (r=0.48, p<0.05), MIP (r=0.73, p<0.01), and MEP (r=0.60, p<0.01). In addition, the multiple regression analysis model indicated that FVC could be predicted by the assessment of each waist mobility and MIP. Conclusion: These finding suggest that respiratory function is related to body size and respiratory muscle strength, and that BMI, waist mobility, and MIP can be predictable factors to affected respiratory function in term of FVC.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.736-745
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• 1998

Background: Respiratory muscle interaction is further profoundly affected by a number of pathologic conditions. Hyperinflation may be particularly severe in chronic obstructive pulmonary disease(COPD) patients, in whom the functional residual capacity(FRC) often exceeds predicted total lung capacity(TLC). Hyperinflation reduces the diaphragmatic effectiveness as a pressure generator and reduces diaphragmatic contribution to chest wall motion. Ultrasonography has recently been shown to be a sensitive and reproducible method of assessing diaphragmatic excursion. This study was performed to evaluate how differences of diaphragmatic excursion measured by ultrasonography associate with normal subjects and COPD patients. Methods: We measured diaphragmatic excursions with ultrasonography on 28 healthy subjects(l6 medical students, 12 age-matched control) and 17 COPD patients. Ultrasonographic measurements were performed during tidal breathing and maximal respiratory efforts approximating vital capacity breathing using Aloka KEC-620 with 3.5 MHz transducer. Measurements were taken in the supine posture. The ultrasonographic probe was positioned transversely in the midclavicular line below the right subcostal margin. After detecting the right hemidiaphragm in the B-mode the ultrasound beam was then positioned so that it was approximately parallel to the movement of middle or posterior third of right diaphragm. Recordings in the M-mode at this position were made throughout the test. Measurements of diaphragmatic excursion on M-mode tracing were calculated by the average gap in 3 times-respiration cycle. Pulmonary function test(SensorMedics 2800), maximal inspiratory(PImax) and expiratory mouth pressure(PEmax, Vitalopower KH-101, Chest) were measured in the seated posture. Results: During the tidal breathing, diaphragmatic excursions were recorded $1.5{\pm}0.5cm$, $1.7{\pm}0.5cm$ and $1.5{\pm}0.6cm$ in medical students, age-matched control group and COPD patients, respectively. Diaphragm excursions during maximal respiratory efforts were significantly decreased in COPD patients ($3.7{\pm}1.3cm$) when compared with medical students, age-matched control group($6.7{\pm}1.3cm$, $5.8{\pm}1.2cm$, p< 0.05}. During maximal respiratory efforts in control subjects, diaphragm excursions were correlated with $FEV_1$, FEVl/FVC, PEF, PIF, and height. In COPD patients, diaphragm excursions during maximal respiratory efforts were correlated with PEmax(maximal expiratory pressure), age, and %FVC. In multiple regression analysis, the combination of PEmax and age was an independent marker of diaphragm excursions during maximal respiratory efforts with COPD patients. Conclusion: COPD subjects had smaller diaphragmatic excursions during maximal respiratory efforts than control subjects. During maximal respiratory efforts in COPD patients, diaphragm excursions were well correlated with PEmax. These results suggest that diaphragm excursions during maximal respiratory efforts with COPD patients may be valuable at predicting the pulmonary function.

• Tuberculosis and Respiratory Diseases
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• v.51 no.6
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• pp.570-578
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• 2001

Background: With cases of chronic obstructive pulmonary disease(COPD), weight loss and low body weight have been found to correlate with increased mortality and poor prognosis. Therefore, nutritional aspects are an important part of the treatment in cases of COPD. In Korea, there is only limited data available for the changes of resting pulmonary function in relation to nutritional status. This study was carried out to investigate the differences of resting pulmonary function in relation to the nutritional status of patients with COPD. Method : 83 stable patients, with moderate to severe COPD, were clinically assessed for their nutritional status and resting pulmonary function. The patients' nutritional status was evaluated by body weight and fat-free mass (FFM), which was assessed by bioelectrical impedance analysis. According to their nutritional status, the 83 patients were divided into two groups, designated as the depleted, and non-depleted, groups. Result : Of the 83 patients, 31% were characterized by body weight loss and depletion of FFM, whereas 28% had either weight loss or depleted FFM. In the depleted group, significantly lower peak expiratory flow rate(p<0.05) and Kco(p<0.01), but significantly higher airway resistance(Raw, p<0.05) were noted. There was no difference for the non-depleted group in forced expiratory volume at one second, residual volume, inspiratory vital capacity, or total lung capacity. Maximal inspiratory pressure($P_{Imax}$) was also significantly lower in the depleted group(p<0.05). Conclusion : We conclude, from our clinical studies, that nutritional depletion is significantly associated with the change in resting pulmonary function for patients with moderate to severe COPD.