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The Influence of Fat-Free Mass to Maximum Exercise Performance in Patients with Chronic Obstructive Pulmonary Disease (만성폐쇄성폐질환에서 제지방량이 최대운동능력에 미치는 영향)

  • Mun, Yeung Chul;Park, Hye Jung;Shin, Kyeong Cheol;Chung, Jin Hong;Lee, Kwan Ho
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.4
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    • pp.346-354
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    • 2002
  • Background : Dyspnea and a limitation in exercise performance are important cause of disability in patients with chronic obstructive pulmonary disease(COPD). A depleted nutritional state is a common problem in patients with a severe degree of chronic airflow limitation. This study was carried out to assess the factors determining the maximum exercise capacity in patients with COPD. Methods : The resting pulmonary function, nutritional status, and maximum exercise performance was assessed in 83 stable patients with moderate to severe COPD. The nutritional status was evaluated by bioelectrical impedance analysis. Maximum exercise performance was evaluated by maximum oxygen uptake($VO_2max$). Results : Among the 83 patients, 59% were characterized by nutritional depletion. In the depleted group, a significantly lower peak expiratory flow rate(p<0.05), Kco(p<0.01) and maximum inspiratory pressure(p<0.05), but a significantly higher airway resistance(p<0.05) was observed. The maximum oxygen uptake and the peak oxygen pulse were lower in the depleted group. The $VO_2max$ correlated with some of the measures of the body composition : fat-free mass(FFM), fat mass(FM), body mass index(BMI), intracellular water index(ICW index), and pulmonary function : forced vital capacity(FVC), forced inspiratory vital capacity(FIVC), diffusion capacity(DLCO) : or maximum respiratory pressure : maximum inspiratory pressure(PImax), maximum expiratory pressure(PEmax). Stepwise regression analysis demonstrated that the FFM, DLCO and FIVC accounted for 68.8% of the variation in the $VO_2max$. Conclusion : The depletion of the FFM is significant factor for predicting the maximum exercise performance in patients with moderate to severe COPD.

COMPARISON OF FLUX AND RESIDENT CONCENTRATION BREAKTHROUGH CURVES IN STRUCTURED SOIL COLUMNS (구조토양에서의 침출수와 잔존수농도의 파과곡선에 관한 비교연구)

  • Kim, Dong-Ju
    • Journal of Korea Soil Environment Society
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    • v.2 no.2
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    • pp.81-94
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    • 1997
  • In many solute transport studies, either flux or resident concentration has been used. Choice of the concentration mode was dependent on the monitoring device in solute displacement experiments. It has been accepted that no priority exists in the selection of concentration mode in the study of solute transport. It would be questionable, however, to accept the equivalency in the solute transport parameters between flux and resident concentrations in structured soils exhibiting preferential movement of solute. In this study, we investigate how they differ in the monitored breakthrough curves (BTCs) and transport parameters for a given boundary and flow condition by performing solute displacement experiments on a number of undisturbed soil columns. Both flux and resident concentrations have been simultaneously obtained by monitoring the effluent and resistance of the horizontally-positioned TDR probes. Two different solute transport models namely, convection-dispersion equation (CDE) and convective lognormal transfer function (CLT) models, were fitted to the observed breakthrough data in order to quantify the difference between two concentration modes. The study reveals that soil columns having relatively high flux densities exhibited great differences in the degree of peak concentration and travel time of peak between flux and resident concentrations. The peak concentration in flux mode was several times higher than that in resident one. Accordingly, the estimated parameters of flux mode differed greatly from those of resident mode and the difference was more pronounced in CDE than CLT model. Especially in CDE model, the parameters of flux mode were much higher than those of resident mode. This was mainly due to the bypassing of solute through soil macropores and failure of the equilibrium CDE model to adequate description of solute transport in studied soils. In the domain of the relationship between the ratio of hydrodynamic dispersion to molecular diffusion and the peclet number, both concentrations fall on a zone of predominant mechanical dispersion. However, it appears that more molecular diffusion contributes to the solute spreading in the matrix region than the macropore region due to the nonliearity present in the pore water velocity and dispersion coefficient relationship.

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The Correlation of Dyspnea and Radiologic Quantity in Patients with COPD (만성폐쇄성폐질환 환자에서 호흡곤란과 영상학적 정량과의 상관관계)

  • Jung, Eun Jung;Kim, Yang Ki;Lee, Young Mok;Kim, Ki-Up;Uh, Soo-Taek;Kim, Yong Hoon;Kim, Do Jin;Park, Choon Sik;Hwang, Jung Hwa
    • Tuberculosis and Respiratory Diseases
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    • v.66 no.4
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    • pp.288-294
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    • 2009
  • Background: A lung hyperinflation, or air trapping, caused by expiratory flow-limitation contributes to dyspnea in patients with chronic obstructive pulmonary disease (COPD). Forced expiratory volume in 1 second ($FEV_1$) has served as an important diagnostic measurement of COPD, but does not correlate with patient-centered outcomes such as dyspnea. Therefore, this study was performed to investigate the role of radiologic quantity in evaluating the dyspnea in patients with COPD by measuring lung hyperinflation in chest x-ray and high resolution chest tomography (HRCT). Methods: Fifty patients with COPD were enrolled in this study. Their subjective dyspnea score (modified Borg scale dyspnea index), spirometry, and lung volume were measured. Simultaneous hyperinflations of chest x-ray score ("chest score") and degree of emphysema of HRCT ("HRCT score") were measured. The "chest score" were composed of lung length, retrosternal space width, and height of the arc of the diaphragm and "HRCT score" were composed of severity and extent of emphysema. Results: The mean age of patients was 69 years old and their mean $FEV_1$ was 51.7%. The Borg score significantly correlated with parameters of spirometry and lung volume, including FVC, $FEV_1$, $FEV_1$/FVC, RV, RV/TLC, and DLCO. The Borg score correlated well with "HRCT score", but did not correlate with "chest score". Also, the Borg scale correlates inversely with body mass index. Conclusion: The quantity of emphysema on chest HRCT may serve as an objective marker of dyspnea in patients with COPD.

The Effect of Pentoxifylline on Radiation-Induced Cardiac Injury in ICR Mice (방사선조사후 발생한 심장손상에서 Pentoxifylline 이 미치는 효과)

  • Suh Hyun Suk;Yang Kwang Mo;Kang Seung Hee;Kang Yun Kyung
    • Radiation Oncology Journal
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    • v.14 no.4
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    • pp.281-290
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    • 1996
  • Purpose : Chest irradiation leads to a significant cardiac injury in a number of patients. To prevent, or to reduce the risk of radiation-induced cardiac injury, pentoxifylline(PTX), a haemorrheologic agent that improves the blood flow through small blood capillaries has been employed. Materials and Methods : One hundred and eighty ICR mice were divided into three study groups: control, radiation alone, and radiation-pentoxifylline. Each group was subdivided into 12 subgroups: 1 3, 6 and 10 days and 2, 3, 4, 6, 8, 12, 16 and 20 weeks by observation Period after irradiation. The total 15Gy of radiation was delivered in a single fraction through anterior mediastinal port. Pentoxifylline was injected subcutaneously daily 50mg/kg to the back of the mice from the first day of irradiation throughout the observation period. The mice of each group after a certain observation period were sacrificed and sectioned for histopathologic examination of the heart. Result : The findings of acute radiation-induced carditis i.e., heterophilic infiltration and vacuolization and ballooning of endothelial cells were observed upto 6 weeks and reduced sharply afterwards. The late radiation effects including pericarditis with mononuclear cell infiltration, pericardial fibrosis, endothelial cell changes, myocardial degeneration and fibrosis present from 4 weeks onwards after irradiation but with various degree of severity. The overall process of pathologic changes of radiation-pentoxifylline group was similar to those of radiation alone group but the duration of acute stage was relatively short and the severity of late cardiac toxicity was much lesser compared with those of radiation alone group. Conclusion : Pentoxifylline can effectively reduce the late radiation-induced cardiac injury and reslve the acute effects relatively rapidly.

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Improvement of Fontan Circulatory Failure after Conversion to Total Cavopulmonary Connection (완전 대정맥-폐동맥 연결수술로 전환 후의 폰탄순환장애 개선)

  • Han Ki Park;Gijong Yi;Suk Won Song;Sak Lee;Bum Koo Cho;Young hwan Park
    • Journal of Chest Surgery
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    • v.36 no.8
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    • pp.559-565
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    • 2003
  • By improving the flow pattern in Fontan circuit, total cavopulmonary connection (TCPC) could result in a better outcome than atriopulmonary connection Fontan operation. For the patients with impaired hemodynamics after atriopulmonary Fontan connection, conversion to TCPC can be expected to bring hemodynamic and functional improvement. We studied the results of the revision of the previous Fontan connection to TCPC in patients with failed Fontan circulation. Material and method: From October1979 to June 2002, eight patients who had failed Fontan circulation, underwent revision of previous Fontan operation to TCPC at Yonsei University Hospital. Intracardiac anomalies of the patients were tricuspid atresia (n=4) and other functional single ventricles (n=4). Mean age at TCPC conversion was 14.0$\pm$7.0 years (range, 4.6~26.2 years) and median interval between initial Fontan operation and TCPC was 7.5 years (range, 2.4~14.3 years). All patients had various degree of symptoms and signs of right heart failure. NYHA functional class was 111 or IV in six patients. Paroxysmal atrial fibrillation (n:f), cyanosis (n=2), intraatrial thrombi (n=2), and protein losing enteropathy (PLE) (n=3) were also combined. The previous Fontan operation was revised to extracardiac conduit placement (n=7) and intraatrial lateral tunnel (n=1). Result: There was no operative death. Major morbidities included deep sternal infection (n=1), prolonged pleural effusion over two weeks (n=1), and temporary junctional lachyarrhythrnia (n=1). Postoperative central venous Pressure was lower than the preoperative value (17.9$\pm$3.5 vs. 14.9$\pm$1.0, p=0.049). Follow-up was complete in all patients and extended to 50,1 months (mean, 30.3$\pm$ 12.8 months). There was no late death. All patients were in NYHA class 1 or 11. Paroxysmal supraventricular tachycardia developed in a patient who underwent conversion to intraatrial lateral tunnel procedure, PLE was recurred in two patients among three patients who had had PLE before the convertsion. There was no newly developed PLE. Conclusion: Hemodynamic and functional improvement could be expected for the patients with Fontan circulatory failure after atriopulmonary connection by revision of their previous circulation to TCPC. The conversion could be performed with low risk of morbidity and mortality.

A Study on the Development of a Simulation Model for Predicting Soil Moisture Content and Scheduling Irrigation (토양수분함량 예측 및 계획관개 모의 모형 개발에 관한 연구(I))

  • 김철회;고재군
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.19 no.1
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    • pp.4279-4295
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    • 1977
  • Two types of model were established in order to product the soil moisture content by which information on irrigation could be obtained. Model-I was to represent the soil moisture depletion and was established based on the concept of water balance in a given soil profile. Model-II was a mathematical model derived from the analysis of soil moisture variation curves which were drawn from the observed data. In establishing the Model-I, the method and procedure to estimate parameters for the determination of the variables such as evapotranspirations, effective rainfalls, and drainage amounts were discussed. Empirical equations representing soil moisture variation curves were derived from the observed data as the Model-II. The procedure for forecasting timing and amounts of irrigation under the given soil moisture content was discussed. The established models were checked by comparing the observed data with those predicted by the model. Obtained results are summarized as follows: 1. As a water balance model of a given soil profile, the soil moisture depletion D, could be represented as the equation(2). 2. Among the various empirical formulae for potential evapotranspiration (Etp), Penman's formula was best fit to the data observed with the evaporation pans and tanks in Suweon area. High degree of positive correlation between Penman's predicted data and observed data with a large evaporation pan was confirmed. and the regression enquation was Y=0.7436X+17.2918, where Y represents evaporation rate from large evaporation pan, in mm/10days, and X represents potential evapotranspiration rate estimated by use of Penman's formula. 3. Evapotranspiration, Et, could be estimated from the potential evapotranspiration, Etp, by introducing the consumptive use coefficient, Kc, which was repre sensed by the following relationship: Kc=Kco$.$Ka+Ks‥‥‥(Eq. 6) where Kco : crop coefficient Ka : coefficient depending on the soil moisture content Ks : correction coefficient a. Crop coefficient. Kco. Crop coefficients of barley, bean, and wheat for each growth stage were found to be dependent on the crop. b. Coefficient depending on the soil moisture content, Ka. The values of Ka for clay loam, sandy loam, and loamy sand revealed a similar tendency to those of Pierce type. c. Correction coefficent, Ks. Following relationships were established to estimate Ks values: Ks=Kc-Kco$.$Ka, where Ks=0 if Kc,=Kco$.$K0$\geq$1.0, otherwise Ks=1-Kco$.$Ka 4. Effective rainfall, Re, was estimated by using following relationships : Re=D, if R-D$\geq$0, otherwise, Re=R 5. The difference between rainfall, R, and the soil moisture depletion D, was taken as drainage amount, Wd. {{{{D= SUM from { {i }=1} to n (Et-Re-I+Wd)}}}} if Wd=0, otherwise, {{{{D= SUM from { {i }=tf} to n (Et-Re-I+Wd)}}}} where tf=2∼3 days. 6. The curves and their corresponding empirical equations for the variation of soil moisture depending on the soil types, soil depths are shown on Fig. 8 (a,b.c,d). The general mathematical model on soil moisture variation depending on seasons, weather, and soil types were as follow: {{{{SMC= SUM ( { C}_{i }Exp( { - lambda }_{i } { t}_{i } )+ { Re}_{i } - { Excess}_{i } )}}}} where SMC : soil moisture content C : constant depending on an initial soil moisture content $\lambda$ : constant depending on season t : time Re : effective rainfall Excess : drainage and excess soil moisture other than drainage. The values of $\lambda$ are shown on Table 1. 7. The timing and amount of irrigation could be predicted by the equation (9-a) and (9-b,c), respectively. 8. Under the given conditions, the model for scheduling irrigation was completed. Fig. 9 show computer flow charts of the model. a. To estimate a potential evapotranspiration, Penman's equation was used if a complete observed meteorological data were available, and Jensen-Haise's equation was used if a forecasted meteorological data were available, However none of the observed or forecasted data were available, the equation (15) was used. b. As an input time data, a crop carlender was used, which was made based on the time when the growth stage of the crop shows it's maximum effective leaf coverage. 9. For the purpose of validation of the models, observed data of soil moiture content under various conditions from May, 1975 to July, 1975 were compared to the data predicted by Model-I and Model-II. Model-I shows the relative error of 4.6 to 14.3 percent which is an acceptable range of error in view of engineering purpose. Model-II shows 3 to 16.7 percent of relative error which is a little larger than the one from the Model-I. 10. Comparing two models, the followings are concluded: Model-I established on the theoretical background can predict with a satisfiable reliability far practical use provided that forecasted meteorological data are available. On the other hand, Model-II was superior to Model-I in it's simplicity, but it needs long period and wide scope of observed data to predict acceptable soil moisture content. Further studies are needed on the Model-II to make it acceptable in practical use.

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Supraclavicular Brachial Plexus block with Arm-Hyperabduction (상지(上肢) 외전위(外轉位)에서 시행(施行)한 쇄골상(鎖骨上) 상완신경총차단(上腕神經叢遮斷))

  • Lim, Keoun;Lim, Hwa-Taek;Kim, Dong-Keoun;Park, Wook;Kim, Sung-Yell;Oh, Hung-Kun
    • The Korean Journal of Pain
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    • v.1 no.2
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    • pp.214-222
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    • 1988
  • With the arm in hyperabduction, we have carried out 525 procedures of supraclavicular brachial plexus block from Aug. 1976 to June 1980, whereas block with the arm in adduction has been customarily performed by other authors. The anesthetic procedure is as follows: 1) The patient lies in the dorsal recumbent position without a pillow under his head or shoulder. His arm is hyperabducted more than a 90 degree angle from his side, and his head is turned to the side opposite from that to be blocked. 2) An "X" is marked at a point 1 cm above the mid clavicle, immediately lateral to the edge of the anterior scalene muscle, and on the palpable portion of the subclavian artery. The area is aseptically prepared and draped. 3) A 22 gauge 3.5cm needle attached to a syringe filled with 2% lidocaine (7~8mg/kg of body weight) and epineprine(1 : 200,000) is inserted caudally toward the second portion of the artery where it crosses the first rib and parallel with the lateral border of the muscle until a paresthesia is obtained. 4) Paresthesia is usually elicited while inserting the needle tip about 1~2 em in depth. If so, the local anesthetic solution is injected after careful aspiration. 5) If no paresthesia is elicited, the needle is withdrawn and redirected in an attempt to elicit paresthesia. 6) If, after several attempts, no paresthesia is obtained, the local anesthetic solution is injected into the perivascular sheath after confirming that the artery is not punctured. 7) Immediately after starting surgery, Valium is injected for sedation by the intravenous route in almost all cases. The age distribution of the cases was from 11 to 80 years. Sex distribution was 476 males and 49 females (Table 1). Operative procedures consisted of 103 open reductions, 114 skin grafts combined with spinal anesthesia in 14, 87 debridements, 75 repairs, i.e. tendon (41), nerve(32), and artery (2), 58 corrections of abnormalities, 27 amputations above the elbow (5), below the elbow (3) and fingers (17), 20 primary closures, 18 incisions and curettages, 2 replantations of cut fingers. respectively (Table 2). Paresthesia was obtained in all cases. Onset of analgesia occured within 5 minutes, starting in the deltoid region in almost all cases. Complete anesthesia of the entire arm appeared within 10 minutes but was delayed 15 to 20 minutes in 5 cases and failed in one case. Thus, our success rate was nearly 100%. The duration of anesthesia after a single injection ranged from $3\frac{1}{2}$ to $4\frac{1}{2}$, hours in 94% of the cases. The operative time ranged from 0.5 to 4 hours in 92.4% of the cases(Table 3). Repeat blocks were carried out in 33 cases when operative times which were more than 4 hours in 22 cases and the others were completed within 4 hours (Table 4). Two patients of the 33 cases, who received microvasular surgery were injected twice with 2% lidocaine 20 ml for a total of $13\frac{1}{2}$ hours. The 157 patients who received surgery on the forearms or hands had pneumatic tourniquets (250 torrs) applied without tourniquet pain. There was no pneumothorax, hematoma or phrenic nerve paralysis in any of the unilateral and 27 bilateral blocks, but there was hoarseness in two, Horner's syndrome in 11 and shivering in 7 cases. No general seizures or other side effects were observed. By 20ml of 60% urcgratin study, we confirm ed the position of the needle tip to be in a safer position when the arm is in hyperabduction than when it is in adduction. And also that the humoral head caused some obstraction of the distal flow of the dye, indicating that less local anesthetic solution would be needed for satisfactory anesthesia. (Fig. 3,4).

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Effect of Various Mixing Ratio of Non-glutinous and Glutinous Rice on Physical and Rheological Properties of Extrudate (멥쌀과 찹쌀의 혼합비율별 압출성형물의 물리적 성질 및 유동특성)

  • Kum, Jun-Seok;Kwon, Sang-Oh;Lee, Hyun-Yu;Lee, Sang-Hyo;Jung, Jin-Hyub;Kim, Jun-Pyong
    • Korean Journal of Food Science and Technology
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    • v.26 no.4
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    • pp.442-447
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    • 1994
  • Effect of different mixing ratio of non-glutinous and glutinous rice on physical and rheological properties of extrudate prepared in a single screw extruder were examined. The extrusion conditions in term of screw speeds, moisture content and die temperature were 258 rpm, 18% and $120^{\circ}C$, respectively. The resisdence time distribution of the most of materials were within 30 second and small portion of them went up to 80 second. The expansion ratio was the highest value (2.93) for 70% of glutinous rice in the mixture, while the lowest value for 100% of non-glutinous rice. Breaking strength was in the range between 1,051g and 1,117g for $10{\sim}20%$ of glutinous rice in the mixture, while the lowest value (737g) for 80%r of glutinous rice. As the amount of glutinous rice increased, L and a values were increased and b value was decreased. The uncooked cold paste viscosity had 400 B.U. for 100% non-glutinous rice , while no peak for the 100% glutinous rice. As the amount of glutinous rice increased up to 100%, the water absorption index (WAI) was decreased, while water solubility index (WSI) was increased. The rheological properties of extrudate were accounted by the law of Oswald. The flow behavior index of extrudate was less than 1.0, which showed pseudoplastic behavior. Yield stress was the highest value for 20% of glutinous rice in the mixture and the lowest value for $80{\sim}100%$ of glutinous; rice. Number of air cell was between 128 and 159 for $80{\sim}100%$ of glutinous rice in the mixture, while $81{\sim}84%$ for $0{\sim}20%$ of glutinous rice. The degree of shapefact was increased more when the mixtures of glutinous and non-glutinous rice was used than when glutinous or non-glutinous rice was only used.

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Dysfunction of Autonomic Nervous System in Patients with Chronic Obstructive Pulmonary Diseases (만성 폐쇄성 폐질환 환자의 자율신경 장애)

  • Shin, Kyeong-Cheol;Lee, Kwan-Ho;Park, Hye-Jung;Shin, Chang-Jin;Lee, Choong-Ki;Chung, Jin-Hong;Lee, Hyun-Woo
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.3
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    • pp.317-326
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    • 1999
  • Background: Neural control of airway function is through parasympathetic, sympathetic and non-adrenergic, non-cholinergic mechanisms. The autonomic nervous system controls the airway smooth muscle tone, mucociliary system, permeability and blood flow in the bronchial circulation and release of mediators from the mast cells and other inflammatory cells. The cardiovascular and respiratory autonomic efferent fibers have a common central origin, so altered cardiovascular autonomic reflexes could reflect the altered respiratory autonomic status. Therefore, we performed this study to assess the autonomic abnormality and determine the correlating factors of severity of autonomic neuropathy in patients with chronic obstructive pulmonary disease(COPD) using easily reproducible cardiovascular autonomic reflex function test. Method: The study included 20 patients with COPD and 20 healthy persons obtained on Health Promotion Center in Yeungnam university hospital. All the patients had history and clinical features of COPD as defined by the American Thoracic Society. Any patients with myocardial ischemia, cardiac arrythmia, hypertension, central or peripheral nervous system disease, diabetes mellitus, or any other diseases known to produce autonomic neuropathy, has excluded. The autonomic nervous system function tests included three tests evaluating the parasympathetic system and two tests evaluating the sympathetic system. And also all subjects were subjected to pulmonary function test and arterial blood gas analysis. Results: Autonomic dysfunction was more commonly associated with patients with COPD than healthy person The parasympathetic dysfunction was frequent in patient with COPD, but sympathetic dysfunction seemed preserved. The severity of parasympathetic dysfunction in patients with COPD was correlated with the degree of duration of disease, smoking, reductions in the value of $FEV_1$ and FVC, and arterial hypoxemia but no such correlation existed for age, type of COPD, $FEV_1$/FVC, or $PaCO_s$. Conclusion: There is high frequency of parasympathetic dysfunction associated with COPD and the parasympathetic abnormality in COPD is increased in proportion to severity of airway disease. In COPD, parasympathetic dysfunction probably does not the cause of disease, but it may be an effect of disease progression.

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Effect of Hypothermia on the Prevention of Ventilator-Induced Lung Injury in Rats (백서에서 저체온 전처치가 환기기유발폐손상 억제에 미치는 효과)

  • Lim, Chae-Man;Hong, Sang-Bum;Koh, Youn-Suck;Shim, Tae-Sun;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.5
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    • pp.540-548
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    • 2001
  • Backgrounds : Because ventilator-induced lung injury is partly dependent on the intensity of vascular flow, we hypothesized that hypothermia may attenuate the degree of such an injury through a reduced cardiac output. Methods : Twenty-seven male Sprague-Dawley rats were randomly assigned to normothermia ($37{\pm}1^{\circ}C$)-injurious ventilation (NT-V) group (n=10), hypothermia ($27{\pm}1^{\circ}C$)-injurious ventilation (HT-V) group (n=10), or nonventilated control group (n=7). The two thermal groups were subjected to injurious mechanical ventilation for 20 min with peak airway pressure 30 cm $H_2O$ at zero positive end-expiratory pressure, which was translated to tidal volume $54{\pm}6\;ml$ in the NT-V group and $53{\pm}4\;ml$ in the HT-V group (p>0.05). Results : Pressure-volume (P-V) curve after the injurious ventilation was almost identical to the baseline P-V curve in the HT-V group, whereas it was shifted rightward in the NT-V group. On gross inspection, the lungs of the HT-V group appeared smaller in size, and showed less hemorrhage especially at the dependent regions, than the lungs of the NT-V group. [Wet lung weight (g)/body weight (kg)] ($1.6{\pm}0.1$ vs $2.4{\pm}1.2$ ; p=0.014) and [wet lung weight/dry lung weight] ($5.0{\pm}0.1$ vs $6.1{\pm}0.8$ ; p=0.046) of the HT-V group were both lower than those of the NT-V group, while not different from those of the control group($1.4{\pm}0.4$, $4.8{\pm}0.4$, respectively). Protein concentration of the BAL fluid of the HT-V group was lower than that of the NT-V group($1,374{\pm}726\;ug/ml$ vs $3,471{\pm}1,985\;ug/ml$;p=0.003). Lactic dehydrogenase level of the BAL fluid of the HT-V group was lower than that of the NT-V group ($0.18{\pm}0.10\;unit/ml$ vs $0.43{\pm}0.22\;unit/ml$;p=0.046). Conclusions : Hypothermia attenuated pulmonary hemorrhage, permeability pulmonary edema, and alveolar cellular injuries associated with injurious mechanical ventilation, and preserved normal P-V characteristics of the lung in rats.

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