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The comparison of lesion localization methods in breast lymphoscintigraphy (Breast lymphoscintigraphy 검사 시 체표윤곽을 나타내는 방법의 비교)

  • Yeon, Joon ho;Hong, Gun chul;Kim, Soo yung;Choi, Sung wook
    • The Korean Journal of Nuclear Medicine Technology
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    • v.19 no.2
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    • pp.74-80
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    • 2015
  • Purpose Breast lymphoscintigraphy is an important technique to present for body surface precisely, which shows a lymph node metastasis of malignant tumors at an early stage and is performed before and after surgery in patients with breast cancer. In this study, we evaluated several methods of body outline imaging to present exact location of lesions, as well as compared respective exposure doses. Materials and Methods RANDO phantom and SYMBIA T-16 were used for obtaining imaging. A lesion and an injection site were created by inserting a point source of 0.11 MBq on the axillary sentinel lymph node and 37 MBq on the right breast, respectively. The first method for acquiring the image was used by drawing the body surface of phantom for 30 sec using $Na^{99m}TcO_4$ as a point source. The second, the image was acquired with $^{57}Co$ flood source for 30 seconds on the rear side and the left side of the phantom, the image as the third method was obtained using a syringe filled with 37 MBq of $Na^{99m}TcO_4$ in 10 ml of saline, and as the fourth, we used a photon energy and scatter energy of $^{99m}Tc$ emitting from phantom without any addition radiation exposure. Finally, the image was fused the scout image and the basal image of SPECT/CT using MATLAB$^{(R)}$ program. Anterior and lateral images were acquired for 3 min, and radiation exposure was measured by the personal exposure dosimeter. We conducted preference of 10 images from nuclear medicine doctors by the survey. Results TBR values of anterior and right image in the first to fifth method were 334.9 and 117.2 ($1^{st}$), 266.1 and 124.4 ($2^{nd}$), 117.4 and 99.6 ($3^{rd}$), 3.2 and 7.6 ($4^{th}$), and 565.6 and 141.8 ($5^{th}$). And also exposure doses of these method were 2, 2, 2, 0, and $30{\mu}Sv$, respectively. Among five methods, the fifth method showed the highest TBR value as well as exposure dose, where as the fourth method showed the lowest TBR value and exposure dose. As a result, the last method ($5^{th}$) is the best method and the fourth method is the worst method in this study. Conclusion Scout method of SPECT/CT can be useful that provides the best values of TBR and the best score of survey result. Even though personal exposure dose when patients take scout of SPECT/CT was higher than another scan, it was slight level comparison to 1 mSv as the dose limit to non-radiation workers. If the scout is possible to less than 80 kV, exposure dose can be reduced, and also useful lesion localization provided.

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Anatomical Variations in the Communicating Rami of the Upper Thoracic Sympathetic Ganglia Related to the Essential Palmar Hyperhidrosis (본태성 수부 다한증에 관련된 상부 흉부교감신경절 교통가지의 해부학적 변이)

  • Cho, Hyun-Min;Kim, Kil-Dong;Lee, Sak;Chung, Kyung-Young
    • Journal of Chest Surgery
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    • v.36 no.3
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    • pp.182-188
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    • 2003
  • Background: Although ramicotomy (division of the rami communicantes of the thoracic sympathetic ganglia) is a selective and physiological surgical method for essential hyperhidrosis, it has some problems such as higher recurrence rates and the different surgical results among the patients and between left and right sides in the same individual. As one of the factors that are related to the differences in surgical result and recurrences, we investigated the anatomical variations of the rami communicantes. The purpose of this study is to help develop new surgical methods to decrease surgical differences among the patients or between the left and right sides of the same individual and recurrence rates in the clinical application of ramicotomy. Material and Method: We dissected 118 thoracic sympathetic chains in 59 adult Korean cadavers (male: 33, female: 26) to examine the anatomical variations of the rami communicantes from the second to the fourth thoracic sympathetic ganglia that have major components innervating to the hands. After the dissection of bilateral thoracic sympathetic chains, we compared the anatomy of left and right sides and examined the anatomical variations of rami communicantes. Result: The number and variation of communicating rami connecting the spinal nerves and the second sympathetic thoracic ganglion were much larger than lower levels. There was considerably less variability in the anatomy of the rami communicantes at successive levels. Among the 59 cadavers dissected, only 14.3% (9/59) had similar anatomy of thoracic sympathetic chains at both sides. As the components related to the essential palmar hyperhidrosis, intrathoracic nerve of Kuntz from the second thoracic sympathetic ganglion to the first intercostal nerve or brachial plexus were observed in 55.9% (66/118). The incidence of descending rami communicates from the second thoracic sympathetic ganglion to the third intercostal nerve and from the third thoracic sympathetic ganglion to the fourth intercostal nerve were 49.2% (58/118) and 28.0% (33/118). And the incidence of ascending rami communicates from the third thoracic sympathetic ganglion to the second intercostal nerve and from the fourth thoracic sympathetic ganglion to the third intercostal nerve were 6.8% (8/118) and 3.4% (4/118), respectively. Conclusion: Based on the various anatomical evidences of the rami communicantes from this study, only the ramicotomy at the third sympathetic ganglion level is insufficient for the treatment of the essential palmar hyperhidrosis to decrease the difference of surgical results and recurrences. When one is planning to perform the ramicotomy for the essential palmar hyperhidrosis, it is advantageous to divide the intrathoracic nerve of Kuntz on the second rib and the descending or ascending rami communicantes on the third and the fourth ribs as well as all the communicating rami from the third sympathetic ganglion.

The Relationship Between the NF-${\kappa}B$ Activity and Anti-inflammatory Action of Surfactant in the Acute Lung Injury of Rats (백서의 급성폐손상에서 surfactant의 항염증작용과 호중구의 NK-${\kappa}B$ 활성과의 관계)

  • An, Chang-Hyeok;Cha, Young-Joo;Lee, Kyoung-Hee;Yoo, Chul-Gyu;Lee, Byoung-Jun;Jeong, Do-Young;Lee, Sang-Hoon;Shin, Jong-Wook;Kim, Jae-Yeol;Park, In-Won;Choi, Byoung-Whui
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.5
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    • pp.519-529
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    • 2002
  • Background : The therapeutic effects of surfactants on acute lung injury derive not only from their recruiting action on collapsed alveoli but also from their anti-inflammatory action in the alveolar sapce. This study evaluated the anti-inflammatory action of a surfactant in an acute lung injury model of rats by neutrophils were recollected from the BAL fluid and the NF-${\kappa}B$ activity of the neutrophilic nuclear protein was evaluated. Methods : Male Sprague-Dawley rats weighing approximately 300 gram were divided into 3 groups, which consisted of 6 rats respectively. In the control group, normal saline(3ml/kg) was instilled into the trachea twice with 30 minute interval. In two other groups, acute lung injury was induced by the intra-tracheal instillation of LPS(5mg/kg). Thirty minutes later, either a surfactant(ST group; 30mg/kg) or normal saline(NT group: 3ml/kg) was instilled via the trachea. Twenty-four hours after the LPS instillation, the BAL fluid was retrieved to measure the WBC count and cytokine(IL-$1{\beta}$ and IL-6) levels. The neutrophils were isolated from the BAL fluid and the nuclear protein was extracted to evaluate the NF-${\kappa}B$ activity using a eletrophoretic mobility shift assay(EMSA). Results : The WBC count of the BAL fluid of the ST group($3,221{\pm}1,914{\times}10^3/{\mu}l$) was higher than that of the control group($356{\pm}275{\times}10^3/{\mu}l$)(p<0.05) and lower than that of the NT group($5,561{\pm}1,757{\times}10^3/{\mu}l$)(p<0.05)). The BAL fluid level of IL-$1{\beta}$ from the NT group($2,064{\pm}1,082pg/ml$) was higher than those of the ST group($360{\pm}234pg/ml$)(p<0.05) and the control group(0pg/ml)p<0.05) and control group($49{\pm}62pg/ml$)(p<0.05). The NF-${\kappa}B$ activity of the neutrophilic nuclear protein in the ST group and NT group was similar. Conclusion : The surfactant, attenuates the alveolar inflammation in the acute lung injury of rats model. However, its anti-inflammatory action does no't appear to be mediated by the inhibition of NF-${\kappa}B$ activity.

Influence of Age on The Adenosine Deaminase Activity in Patients with Exudative Pleural Effusion (연령의 증가가 삼출성 흉수 Adenosine Deaminase 활성도에 미치는 영향)

  • Yeon, Kyu-Min;Kim, Chong-Ju;Kim, Jeong-Soo;Kim, Chi-Hoon
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.5
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    • pp.530-541
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    • 2002
  • Background : Pleural fluid adenosine deaminase (ADA) activity can be helpful in a differntial diagnosis of an exudative pleural effusion because it is increased in a tuberculous pleural effusion. The ADA activity is determined mainly by the lymphocyte function. Age-associated immune decline is characterized by a decrease in T-lymphocyte function. For that reason, the pleural fluid ADA level would be lower in older patients with exudative pleural effusion. This study focused on the influence of age on the pleural fluid ADA activity in patients with exudative pleural effusion. Methods : A total of 81 patients with exudative pleural effusion were enrolled in this study. In all patients, the pleural fluid ADA activity was measured using an automated kinetic method. Results : The mean age of the patients was $52.7{\pm}21.2$ years. In all patients with exudative pleural effusion, the pleural fluid ADA activity revealed a significant difference between young patients (under 65 years of age) and old patients (p<0.05), and showed a negative correlation with age (r=-0.325, p<0.05). In the 60 patients with a tuberculous pleural effusion, the pleural fluid ADA activity revealed a significant difference between the young and older patients : $103.5{\pm}36.9$ IU/L in young patients Vs. $72.2{\pm}31.6$ IU/L in old patients (p<0.05), and showed a negative correlation with age (r=-0.384, p<0.05). In the 21 patients with non-tuberculous exudative pleural effusion, the pleural fluid ADA activity of the young patients and old patients was similar : $23.7{\pm}15.3$ IU/L in young patients Vs. $16.1{\pm}10.2$ IU/L in old patients (p>0.05), and did not show any correlation with age (r=-0.263, p>0.05). The diagnostic cutoff value of pleural fluid ADA activity for tuberculous pleural effusion was lower in the older patients (25.9 IU/L) than in the younger patients (49.1 IU/L) or all patients (38.4 IU/L) with exudative pleural effusion. Conclusion : Tuberculous pleural effusion is an important possibility to consider in older patients with a clinical suspicion of a tuberculous pleural effusion, although no marked increase in the pleural fluid ADA activity is usually detected. For a diagnosis of a tuberculous pleural effusion in old patients, the cutoff for the pleural fluid ADA activity should be set lower.

Ideal Right Ventricular Outflow Tract Size in Tetralogy of Fallot Total Correction (팔로네징후 완전교정술 시 이상적인 우심실 유출로 크기에 관한 분석)

  • Kim Jin-Sun;Choi Jin-Ho;Yang Ji-Hyuk;Park Pyo-Won;Youm Wook;Jun Tae-Gook
    • Journal of Chest Surgery
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    • v.39 no.8 s.265
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    • pp.588-597
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    • 2006
  • Background: The surgical repair of a tetralogy of Fallot (TOF) has been performed successfully with a favorable early and late outcome. However, the later development of pulmonary regurgitation and stenosis remains a problem. The development of pulmonary regurgitation and stenosis may be changed by the size of right ventricular outflow tract (RVOT) reconstruction at the initial total correction. Hence, it is necessary to investigate the ideal size of RVOT reconstruction. Material and Method: This prospective study was carried out to determine how a surgical strategy and the RVOT size affect the occurrence of pulmonary regurgitation and stenosis. From January 2002 to December 2004, 62 patients underwent the TOF total correction. The RVOT size (diameter of pulmonary valve annulus) of each case was measured after the RVOT reconstruction and converted to a Z value. A pre-scheduled follow up (at discharge, 6 months, 1 year, 2 years and 3 years) was carried out by echocardiography to evaluate the level of pulmonary regurgitation and stenosis. Result: The patients were divided to two groups (transannular group n=12, nontransannular group n=50) according to the method of a RVOT reconstruction. The Z value of RVOT=iameter of pulmonary valve annulus) (transannular group -1, $range\;-3.6{\sim}-0.8;$ nontransannular group -2.1, $range\;-5.2{\sim}-1.5)$ and the average pRV/LV after surgery ${(transannular group 0.44{\pm}0.09,\;nontransannular group\;0.42{\pm}0.09)}$ did not show any significant difference between two groups. The occurrence of pulmonary regurgitation above a moderate degree was more frequent in the transannular group (p<0.01). In nontransannular group, the development of pulmonary regurgitation more than moderate degree occurred to the patients with larger RVOT size (Z value>0, p<0.02) and the progressing pulmonary stenosis more than mild to moderate degree developed in the patients with smaller RVOT size (Z value<-1.5, p<0.05). A moderate degree of pulmonary stenosis developed for 4 nontransannular patients. Three underwent additional surgery and one underwent a balloon valvuloplasty. Their Z value of RVOT were -3.8, -3.8 -2.9, -1.8, respectively. Conclusion: When carring out a TOF total correction, transannular RVOT reconstruction group has significantly more pulmonary regurgitation. In the nontransannular RVOT reconstruction. the size of the RVOT should be maintained from Z value -1.5 to 0. If the Z value is less than -1.5, we should follow up carefully for the possibility of pulmonary stenosis.

The Comparative Study of on Pump CABG during Pulsatile $(T-PLS^{TM})$ and Nonpulsatile $(Bio-pump^{TM})$ Perfusion (관상동맥우회술 시 사용된 박동성펌프$(T-PLS^{TM})$와 비박동성펌프$(Bio-pump^{TM})$의 비교연구)

  • Park Young-Woo;Her Keun;Lim Jae-Ung;Shin Hwa-Kyun;Won Yong-Soon
    • Journal of Chest Surgery
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    • v.39 no.5 s.262
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    • pp.354-358
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    • 2006
  • Background: Pulsatile pumps for extracorporeal circulation have been known to be better for tissue perfusion than non-pulsatile pumps but be detrimental to blood corpuscles. This study is intended to examine the risks and benefits of $T-PLS^{TM}$ through the comparison of clinical effects of $T-PLS^{TM}$ (pulsatile pump) and $Bio-pump^{TM}$ (non-pulsatile pump) used for coronary bypass surgery. Material and Method: The comparison was made on 40 patients who had coronary bypass using $T-PLS^{TM}\;and\;Bio-pump^{TM}$ (20 patients for each) from April 2003 to June 2005. All of the surgeries were operated on pump beating coronary artery bypass graft using cardiopulmonary extra-corporeal circulation. Risk factors before surgery and the condition during surgery and the results were compared. Result: There was no significant difference in age, gender ratio, and risk factors before surgery such as history of diabetes, hypertension, smoking, obstructive pulmonary disease, coronary infarction, and renal failure between the two groups. Surgery duration, hours of heart-lung machine operation, used shunt and grafted coronary branch were little different between the two groups. The two groups had a similar level of systolic arterial pressure, diastolic arterial pressure and mean arterial pressure, but pulse pressure was measured higher in the group with $T-PLS^{TM}\;(46{\pm}15\;mmHg\;in\;T-PLS^{TM}\;vs\;35{\pm}13\;mmHg\;in\;Bio-pump^{TM},\;p<0.05)$. The $T-PLS^{TM}$-operated patients tended to produce more urine volume during surgery, but the difference was not statistically significant $(9.7{\pm}3.9\;cc/min\;in\;T-PLS^{TM}\;vs\;8.9{\pm}3.6\;cc/min\;in\;Bio-pump^{TM},\;p=0.20)$. There was no significant difference in mean duration of respirator usage and 24-hour blood loss after surgery between the two groups. Plasma free Hb was measured lower in the group with $T-PLS^{TM}\;(24.5{\pm}21.7\;mg/dL\;in\;T-PLS^{TM}\;versus\;46.8{\pm}23.0mg/dL\;in\;Bio-pump^{TM},\;p<0.05)$. There was no significant difference in coronary infarction, arrhythmia, renal failure and morbidity rate of cerebrovascular disease. There was a case of death after surgery (death rate of 5%) in the group tested with $T-PLS^{TM}$, but the death rate was not statistically significant. Conclusion: Coronary bypass was operated with $T-PLS^{TM}$ (Pulsatile flow pump) using a heart-lung machine. There was no unexpected event caused by mechanical error during surgery, and the clinical process of the surgery was the same as the surgery for which $Bio-pump^{TM}$ was used. In addition, $T-PLS^{TM}$ used surgery was found to be less detrimental to blood corpuscles than the pulsatile flow has been known to be. Authors of this study could confirm the safety of $T-PLS^{TM}$.

The Effect of a Bypass Operation for Atherosclerotic Arterial Obstructive Disease at the Lower Extremity (동맥경화성 하지 동맥 폐색증에 대한 우회로 수술의 효과)

  • Choi, Won-Suk;Park, Jae-Min;Lee, Yang-Haeng;Han, Il-Yong;Jun, Hee-Jae;Yoon, Young-Chul;Hwang, Youn-Ho;Cho, Kwang-Hyun
    • Journal of Chest Surgery
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    • v.41 no.5
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    • pp.610-618
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    • 2008
  • Background: There are various treatment modalities for atherosclerotic arterial obstructive disease at the lower limbs, for example, conservative physical therapy, medication, operation etc. Yet it has been established that an arterial bypass operation is the most effective treatment. The aim of this study is to evaluate the effect of arterial bypass operation within our experience and to determine the indicators of treatment. Material and Method: Ninety six patients received arterial bypass operation for atherosclerotic arterial obstructive disease from June 2002 to April 2006. We evaluated the feasibility of arterial bypass operation based on the improvement of symptoms and the ankle-brachial index (ABI) and the surgical outcomes, as based on the complications, the amputation rates and the patency rates. We also assessed the possible risk factors such as gender, age, a smoking history, co-morbidities, the anastomotic sites, the graft size and the graft type. We retrospectively reviewed the medical records of the patients. The total mean follow-up period was $29.4{\pm}13.1$ months. Result: The mean age was $65.95{\pm}9.61$ and there were 88 male patients. The most common clinical manifestation was ischemic resting pain in the lower extremities. The underlying combined diseases were hypertension (61%), diabetes (43%), cardiac problems (35%) and smoking (91.7%). The most frequent site of arterial obstruction was the superficial femoral artery (44 cases, 40%). A femoropopliteal artery bypass operation with a Polytetrafluoroethylene(PTFE) synthetic graft was done in 44 cases (40%) and the great saphenous vein graft was used in 11 cases. The postoperative ABI increased significantly from $0.30{\pm}0.11$ preoperatively to $0.63{\pm}0.11$ (p<0.001) postoperatively. In 8 cases, amputations above the ankle level were necessary. The graft patency rates were 86.4% and 68.0% after 1 and 3 years, respectively. There were 29 cases (30.21%) of patency failure; the male gender, smokers and hypertension were significantly more frequent in the failure group. Of these, hypertension was the most powerful risk factor (p=0.042). Conclusion: The arterial bypass operation is an effective treatment modality for controlling the symptoms such as pain and claudication, and for preventing major amputations for the patients with atherosclerotic arterial obstructive disease. This study suggests quitting smoking, strict blood pressure control, selection of an appropriate graft, regular outpatient follow up and proper medication would offer higher patency rates and more favorable outcomes.

Relationship of Compliance and Oxygen Transport in Experimental Acute Respiratory Failure during Positive End-Expiratory Pressure Ventilation (실험적 급성호흡부전에서 호기말양압에 의한 폐유순도와 산소운반의 변화 및 상관관계 - 호흡부전의 기전에 따른 차이 -)

  • Lee, Sang-Do;Yoon, Se-Jin;Lee, Bok-Hee;Han, Sung-Koo;Shim, Young-Soo;Kim, Keun-Youl;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.1
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    • pp.6-15
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    • 1993
  • Background: Positive end, expiratory pressure (PEEP) has become one of the standard therapies for adult respiratory distress syndrome (ARDS). Total static compliance has been proposed as a guide to determine the size of PEEP ('best PEEP') which is of unproven clinical benefit and remains controversial. Besides increasing functional residual capacity and thus improving oxygenation, PEEP stimulate prostacyclin secretion and was proposed for the treatment of acute pulmonary embolism. But little is known about the effect of PEEP on hemodynamic and gas exchange disturbances in acute pulmonary embolism. Methods: To study the validity of total static compliance as a predictor of 'best PEEP' in ARDS and acute pulmonary embolism, experimental ARDS was induced in mongrel dog with oleic acid and acute pulmonary embolism with autologous blood clot. Then hemodynamic and gas exchange parameters were measured with serial increment of PEEP. Results:In ARDS group, total static compliance and oxygen transport were maximal at 5 cm$H_2O$, and decreased thereafter (p<0.05). With increment of PEEP, arterial oxygen tension ($PaO_2$) and arterial carbon dioxide tension ($PaCO_2$) increased and cardiac output and physiological shunt decreased. In pulmonary embolism group, total static compliance, oxygen transport, physiological shunt and cardiac output decreased and $PaO_2$ and $PaCO_2$ increased with increment of PEEP (p<0.05). Comparing the change induced by increment of PEEP by 1 cm$H_2O$ in ARDS group with that in pulmonary embolism group, there was no significant difference between two groups except cardiac output which decreased more in pulmonary embolism group (p<0.05). In ARDS group, oxygen transport and total static compliance increased after PEEP application, and total static compliance was maximal at the PEEP level where oxygen transport was maximal. However in pulmonary embolism group, oxygen transport and total static compliance decreased after application of PEEP. There was significant correlation between change of total static compliance and change of oxygen transport in both groups. Conclusion: In both ARDS and acute pulmonary embolism, it can be concluded that total static compliance is useful as a predictor of 'best PEEP'.

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Hypoxemia In Liver Cirrhosis And Intrapulmonary Shunt Determination Using Tc-99m-MAA Whole Body Scan (간경화 환자에서의 저산소혈증과 Tc-99m-MAA 주사를 이용한 폐내단락 측정)

  • Lee, Kye-Young;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Kim, Keun-Youl;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.5
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    • pp.504-512
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    • 1994
  • Background: It is well known that severe hypoxemia is often associated with liver cirrhosis without preexisting cardiac or pulmonary diseases. Pulmonary vascular impairments, more specifically, intrapulmonary shunting have been considered as a major mechanism. Intrapulmonary shunting arises from pulmonary vascular dilatation at the precapillary level or direct arteriovenous communication and has relationship with the characteristic skin findings of spider angioma. However, these results are mainly from Western countries where alcoholic and primary biliary cirrhosis are dominant cuases of cirrhosis. It is uncertain that the same is true in viral hepatitiss associated liver cirrhosis, which is dominant causes of liver cirrhosis in Korea. We investigated the incidences of hypoxemia and orthodeoxia in Korean cirrhotic patients dominantly composed of postnecrotic cirrhosis and the significance of intrapulmonary shunting as the suggested mechanism of hypoxemia, Method: We performed the arterial blood gas analysis separately both at the supine and errect position in 48 stable cirrhotic patients without the evidences of severe complications such as ascites, variceal bleeding, and hepatic coma. According to the results of arterial blood gas analysis, all patients were divided into hypoxemic and normoxemic group. In each group, pulmonary function test and Tc-99m-MAA whole body scan were performed. The shunting fraction was calculated based on the fact that the sum of cerebral and bilateral renal blood flow is 32% of the systemic blood flow. Results: The hypoxemia of $PaO_2$ less than 80 mmHg was observed in 9 patients(18.8%) and Orthodeoxia more than 10 mmHg was observed in 8 patients(16.7%). But there was no patient with significant hypoxemia of $PaO_2$ less than 60 mmHg. $PaO_2$ was significantly decreased in the patients with spider angioma than the pathients without spider angioma and showed no correlation with the serologic type and severities of liver function test findings. Any parameters of pulmonary function test did not demonstrate the difference between normoxemic and hypoxemic group. But hypoxemic group showed significantly increased shunt fraction of $11.4{\pm}4.1%$ than normoxemic group of $4.1{\pm}2.0%$ (p<0.05). Conclusions: Hypoxemia is not infrequently observed complication in liver cirrhosis and intrapulmonary shunting is suggested to p1ay a major ro1e in the development of hypxemia. But there was no great likelihood of clinically significant hypoxemia in our domestic cirrhotic patients predominantly composed of postnecrotic type.

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Effect of Pressure Rise Time on Tidal Volume and Gas Exchange During Pressure Control Ventilation (압력조절환기법에서 압력상승시간(Pressure Rise Time)이 흡기 일환기량 및 가스교환에 미치는 영향)

  • Jeoung, Byung-O;Koh, Youn-Suck;Shim, Tae-Sun;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong;Lim, Chae-Man
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.5
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    • pp.766-772
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    • 2000
  • Background : Pressure rise time (PRT) is the time in which the ventilator aclieves the set airway pressure in pressure-targeted modes, such as pressure control ventilation (PCV). With varying PRT, in principle, the peak inspiratory flow rate of the ventilator also varies. And if PRT is set to a shorter duration, the effective duration of target pressure level would be prolonged, which in turn would increase inspiratory tidal volume(Vti) and mean airway pressure (Pmean). We also postulated that the increase in Vti with shortening of PRT may relate inversely to the patients' basal airway resistance. Methods : In 13 paralyzed patients on PCV (pressure control 18$\pm$9.5 cm $H_2O$ $FIO_2\;0.6\pm0.3$, PEEP 5$\pm$3 cm $H_2O$, f 20/min, I : E1 : 2) with Servo 300 (Siemens-Elema, Solna, Sweden) from various causes of respiratory failure, PRT of 10 %, 5 % and 0 % were randomly applied. At 30 min of each PRT trial, peak inspiratory flow (PIF, L/sec), Vti (ml), Pmean (cm $H_2O$) and ABGA were determined. Results : At PRT 10%, 5%, and 0%, PIF were 0.69$\pm$0.13, 0.77$\pm$0.19, 0.83$\pm$0.22, respectively (p<0.001). Vti were 425$\pm$94, 439$\pm$101, 456$\pm$106, respectively (p<0.001), and Pmean were 11.2$\pm$3.7, 12.0$\pm$3.7, 12.5$\pm$3.8, respectively (p<0.001). pH were 7.40$\pm$0.08, 7.40$\pm$0.92, 7.41$\pm$0.96, respectively (p=0.00) ; $PaCO_2$ (mm Hg) were 47.4$\pm$15.8, 47.2 $\pm$15.7, 44.6$\pm$16.2, respectively (p=0.004) ; $PAO_2-PaO_2$ (mm Hg) were 220$\pm$98, 224$\pm$95, 227$\pm$94, respectively (p=0.004) ; and $V_n/V_T$ as determined by ($PaCO_2-P_E-CO_2$)/$PaCO_2$ were 0.67$\pm$0.07, 0.67$\pm$0.08, 0.66$\pm$0.08, respectively (p=0.007). The correlation between airway resistance and change of Vti from PRT 10% to 0% were r= -0.243 (p=0.498). Conclusion : Shortening of pressure rise timee during PCV was associated with increased tidal volume, increased mean airway pressure and lower $PaCO_2$.

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