• Journal of Chest Surgery
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• v.35 no.7
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• pp.523-529
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• 2002

Background: Previous reports present that the early results of coronary artery bypass grafting (CABG) has been improving with the accumulation of surgical experience. We conducted a retrospective analysis of the patients who received CABG to evaluate the recent results of CABG. Material and Method: Between January 1996 and August 2001, 154 patients underwent CABG at Hanyang University Hospital. There were 47 patients(group I) who were operated between 1996 and 1998, and 107 patients(group II) who were operated thereafter. The preoperative diagnosis, operative procedure, mortality, and complications were analyzed retrospectively. Result: There were 35 males and 12 females in group I, and 78 males and 29 females in group II, which shows similar ratio of sexes between the two groups. The average age of patients for group I and group II was $55.9{\pm}6.2$ years and $61.0{\pm}8.0$ years, respectively, showing a significant increase in group II(p<0.05). The average left ventricular ejection fraction(LVEF) for group I and group II was $54.6{\pm}11.8$% and $56.9{\pm}13.0$%, respectively. The number of patients who had previous MI in group I and group II were 13 patients(27.7%) and 14 patients(13.1%), respectively, which shows a significant difference (p<0.05). All procedures were performed using the cardiopulmonary bypass(CPB) and moderate systemic hypothermia. Myocardial protection was achieved using intermittent hypothermic ischemia under ventricular fibrillation state or cold crystalloid cardioplegic solution for most of group I patients, whereas cold blood cardioplegic solution was used for group II patients. The mean CPB times for group I and group II were $149.2{\pm}48.7$ minutes and $113.1{\pm}30.6$ minutes, respectively. The mean aortic cross clamp times for group I and group II were $81.3{\pm}26.5$ minutes $72.2{\pm}23.9$ minutes, respectively. These figures show that CPB and aortic cross clamp times were significantly reduced in group II(p<0.05). The use of the left internal thoracic artery(LITA) was increased from 42%(20/47) for group I to 81% (87/107) for group II. The mean number of grafts also significantly increased from $2.5{\pm}0.6$ for group I to $3.0{\pm}1.1$ for group II(p<0.05). Intra-aortic balloon pump(IABP) was applied in 7 cases in group I and 17 cases in group II. Of these, 28.6%(2/7) and 52.9%(9/17) were broadly applied preoperatively in patients with LVEF<40% or congestive heart failure. The operative mortalities for group I and II were 10.6%(5/47) and 0.9%(1/107), respectively, which shows significant decrease for group II(p.0.05). Conclusion: This report suggest that CABG using CPB can recently be performed more safely in virtue of the accumulation of surgical experience with reduction in CPB and aortic cross clamp times and improved surgical techniques and myocardial protection. And we think that the optimal treatment of patients with left ventricular dysfunction associated with congestive heart failure and the extended application of IABP, especially have contributed to the reduction of operative mortality and morbidity.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.380-387
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• 1998

Background: Minimal pressure support(PSmin) is a level of pressure support which offset the imposed work of breathing(WOBimp) developed by endotracheal tube and ventilator circuits in pressure support ventilation While the lower applied level of pressure support compared to PSmin could induce respiratory muscle fatigue, the higher level than PSmin could keep respiratory muscle rest resulting in prolongation of weaning period during weaning from mechanical ventilation PSmin has been usually applied in the level of 5~10 cm$H_2O$, but the accurate level of PSmin is difficult to be determinated in individual cases. PSmin is known to be calculated by using the equation of "PSmin = peak inspiratory flow rate during spontaneus ventilation$\times$total ventilatory system resistance", but correlation of calculated PSmin and measured PSmin has not been known. The objects of this study were firstly to assess whether customarily applied pressure support level of 5~10 cm$H_2O$ would be appropriate to offset the imposed work of breathing among the patients under weaning process, and secondly to estimate the correlation between the measured PSmin and calculated PSmin. Method : 1) Measurement of PSmin : Intratracheal pressure changes were measured through Hi-Lo jet tracheal tube (8mm in diameter, Mallinckroft, USA) by using pulmonary monitor(CP-100 pulmonary monitor, Bicore, USA), and then pressure support level of mechanical ventilator were increased until WOBimp was reached to 0.01 J/L or less. Measured PSmin was defined as the lowest pressure to make WOBimp 0.01 J/L or less. 2) Calculation of PSmin : Peak airway pressure(Ppeak), plateau airway pressure(Pplat) and mean inspiratory flow rate of the subjects were measured on volume control mode of mechanical ventilation after sedation. Spontaneous peak inspiratory flow rates were measured on CPAP mode(O cm$H_2O$). Thereafter PSmin was calculated by using the equation "PSmin = peak inspiratory flow rate$\times$R, R = (Ppeak-Pplat)/mean inspiratory flow rate during volume control mode on mechanical ventilation". Results: Sixteen patients who were considered as the candidate for weaning from mechanical ventilation were included in the study. Mean age was 64(${\pm}14$) years, and the mean of total ventilation times was 9(${\pm}4$) days. All patients except one were males. The measured PSmin of the subjects ranged 4.0~12.5cm$H_2O$ in 14 patients. The mean level of PSmin was 7.6(${\pm}2.5\;cmH_2O$) in measured PSmin, 8.6 (${\pm}3.25\;cmH_2O$) in calculated PSmin Correlation between the measured PSmin and the calculated PSmin is significantly high(n=9, r=0.88, p=0.002). The calculated PSmin show a tendancy to be higher than the corresponding measured PSmin in 8 out of 9 subjects(p=0.09). The ratio of measured PSmin/calculated PSmin was 0.81(${\pm}0.05$). Conclusion: Minimal pressure support levels were different in individual cases in the range from 4 to 12.5 cm$H_2O$. Because the equation-driven calculated PSmin showed a good correlation with measured PSmin, the application of equation-driven PSmin would be then appropriate compared with conventional application of 5~10 cm$H_2O$ in patients under difficult weaning process with pressure support ventilation.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.1
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• pp.50-59
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• 2019

Objectives : Many of the patients with type 2 diabetes are associated with sleep problems, and the rate of insomnia is known to be higher in the general population. The aims of this study were to know the frequency and clnical characteristics of insomnia, and related variables to insomnia in patients diagnosed with type 2 diabetes. Methods : For 99 patients from 18 to 80 years of age (65 males and 34 females) with type 2 diabetes, interviews were performed. Total sleep time and sleep latency was evaluated. Insomnia was evaluated using the Korean Version of the Insomnia Severity Index (ISI-K). Severity of depressive symptoms were evaluted using the Korean version of the Hamilton Depression Scale (K-HDRM). According to the cutoff score of 15.5 on the ISI-K, subjects were divided into the group of type 2 diabetics with insomnia (N=34) and those without insomnia (N=65) at first, and then statistically analyzed. Results : TInsomnia could be found in 34.34% of type 2 diabetics. Type 2 diabetics with insomnia had significantly more single or divorced (respectively 11.8%, p<0.05), higher total scores of the K-HDRS ($11.76{\pm}5.52$, p<0.001), shorter total sleep time ($5.35{\pm}2.00hours$, p<0.001), and longer sleep latency ($50.29{\pm}33.80minutes$, p<0.001). The all item scores of the ISI-K in type 2 diabetics with insomnia were significantly higher than those in type 2 diabetics without insomnia, that is, total ($18.38{\pm}2.69$), A1 (Initial insomnia) ($2.97{\pm}0.76$), A2 (Middle insomnia) ($3.06{\pm}0.69$), A3 (Terminal insomnia) ($2.76{\pm}0.61$), B (Satisfaction) ($3.18{\pm}0.72$), C (Interference) ($2.09{\pm}0.97$), D (Noticeability) ($2.12{\pm}1.09$) and E (Distress) ($2.21{\pm}0.81$) (respectively p<0.001). Variables associated with insomnia in type 2 diabetics were as following. Age had significant negative correlation with A3 items of the ISI-K (${\beta}=-0.241$, p<0.05). Total scores of the K-HDRS had significant positive correlation, while total sleep time had significant negative correlation with all items of the ISI-K (respectively p<0.05). Sleep latency had significant positive correlation with total,, A1, B and E item scores of the ISI-K (respectively p<0.05). Conclusions : Insomnia was found in about 1/3 of type 2 diabetics. According to the presence of insomnia, clinical characteristics including sleep quality as well as quantity seemed to be different. Because depression seemed to be correlated with insomnia, clinicians should pay attention to early detection and intervention of depression among type 2 diabetics.

• Korea Journal of Hospital Management
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• v.8 no.3
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• pp.32-48
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• 2003

Korea is to open its medical markets to foreign hospitals starting in the year 2006 regardless of our will(DDA, Doha Development Agenda). To accurately understand the characteristics of Korean medical users, their detailed and various needs, their attitudes toward the opening of Korean medical markets, and factors affecting these users in choosing foreign medical service providers would be first step needs to be taken by the Korean medical facilities that need to survive and develope through the fiercely competitive era coming with the opening of Korean medical markets to foreign medical service providers and would be very important in hospital management. The subjects of this study were 500 patients randomly selected from the outpatients who visited one of university hospitals in Seoul on the 14th-16th days of April 2003, and conducted a self-completion questionnaire. The answers of 463 respondents among the selected patients(93% of a responding rate)were analyzed through the Excel and statistics programs. The attitudes on the opening of the medical markets were shown in agreement 56.5%(247 persons), disagreement 6.9%(30 persons), and no idea 36.6%(160 persons). In consideration of only the answers as agreement and disagreement exclusive of the answer as no idea, 89.2% of the respondents agreed to the opening of the medical markets while 10.8% objected to the opening. The approval rate was higher with the higher education and income levels. Moreover, The approval rate for the opening of the medical markets was relatively high regardless of the satisfaction in the medical service, and the most important reason of the agreement was the guarantee of the patients(national)option. The main reason of the disagreement was high medical fee(50.5%), and the other reasons showing low rates were outflow of the domestic fund to the foreign countries(13.6%), damage of medical influences on the public(11.4%), lack of competition of the domestic medical industry(9.1%)and so on. As for the factors of selecting the foreign hospitals in the opening of the medical markets, the patients considered the authority(competency)of doctors firstly, and the other principal factors were worldwide fame and reliance, specific explanation of doctors, modernized medical instruments, convenient consultation procedure, etc. The patients agreed to the opening of the medical markets at a high rate regardless of the satisfaction in the medical service, and the most principal reason of the agreement was the guarantee of the patients(national)option for the medical care. Connected with the factors to select the hospitals, the approval reasons for the opening of the medical markets were the authority(competency)of the doctors as the first one, and then fame and tradition, reliance, overall diagnosis and modernized medical instruments, doctors specific explanation, and so on. However, these factors are actually associated with the Quality of the medical care, and consequently the approval reasons for the opening of the medical markets are connected with the security of the medical care. Accordingly, the guarantee of the patients(national)option answered as the main reason of the agreement can be also understood as the awareness of the right to have a variety of options for the security of the medical quality.

• Clinics in Shoulder and Elbow
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• v.16 no.1
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• pp.17-26
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• 2013

Purpose: A comparison of the radiographic and the clinical outcomes between two different surgical approaches-Deltoid splitting and Delto-pectoral interval-on the proximal humerus fractures treated by locking compressive plate (LCP), is done. Materials and Methods: Medical records and pre- and postoperative radiographs were reviewed retrospectively for 75 adult patients who underwent surgical fixations with locking compressive plates from May 2005 to December 2011. Patients were divided into two groups according to the surgical methods. Differences in the neck-shaft angle between immediate postoperative period and final follow-up were compared between the two groups. Differences in constant score and Korean shoulder score (KSS) between affected arms and contralateral arms at final follow-up were also compared. Results: The differences in the neck-shaft angle between immediate postoperative period and at final follow-up was 12.04 degrees on average in Deltoid splitting approach and 10.20 degrees in Delto-pectoral interval approach, which was not statistically significant. Differences in constant score/KSS between the affected arm and the contralateral arm were 13.78/22.74 points in deltoid-splitting approach on average and 19.41/31.13 points in Delto-pectoral interval approach, showing that deltoid-splitting approach is significantly superior. Conclusion: Deltoid-splitting approach showed better functional outcomes in the fracture reduction and internal fixation using LCP for the treatment of unstable proximal humerus fractures.

• Tuberculosis and Respiratory Diseases
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• v.58 no.3
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• pp.276-284
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• 2005

Backgraound : There have been many reports on the pathogenesis of sepsis-induced acute respiratory distress syndrome(ARDS) but, the precise mechanism has not been elucidated. This study examined the protective effect of an inhibition of platelet activating factor(PAF) remodeling and the adhesion molecule on the oxidative stress of the lungs in rats with an endotoxin induced acute lung injury(ALI). Methods : ALI was induced in Sprague-Dawley rats by instilling an E-coli endotoxin into the trachea. Ketotifen and fucoidan were used respectively to inhibit PAF remodeling and adhesion molecule. The lung leak index, lung myeloperoxidase(MPO) activity, bronchoalveolar lavage(BAL) fluid neutrophil count and lyso PAF acetyltransferase activity(AT), were measured and an ultrastructural study and cytochemical electron microscopy were performed. Results : The lung leak index, lung MPO activity, BAL fluid neutrophil count and lyso PAF AT activity was higher in the endotoxin-treated rats. In addition, severe destruction of the pulmonary architecture and increased hydrogen peroxide production were identified. These changes were reversed by ketotifen. However, fucoidan did not appear to have any protective effects. Conclusion : The inhibition of PAF remodeling appeared to be effective in decreasing the endotoxin-induced ALI. In addition, this effect might be derived from the inhibition of neutrophilic oxidative stress. However, the inhibition of the adhesion molecules by fucoidan appeared to be ineffective in decreasing the endotoxin-induced ALI.

• Tuberculosis and Respiratory Diseases
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• v.56 no.5
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• pp.485-494
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• 2004

Background : To assess the effects of mDOT implementation on sputum smear conversion for AFB (Acid fast bacilli) positive pulmonary tuberculosis patients, modified Directly Observed Treatment (mDOT) was started on October $8^{th}$ 2001 at a health center in Seoul. mDOT was defined through weekly interviewing and supervising of a patient by a supervisor (doctor, nurse, or lay health worker). The sputum smear conversion of a mDOT group was compared with that of a self-medication (self) group. Methods : This study included 52 AFB positive pulmonary tuberculosis patients registered at a health center in Seoul between October $8^{th}$ 2001 and April $23^{rd}$ 2002. 24 and 28 patients were enrolled in the mDOT and self medication groups, respectively. Paired (1:1) individual matching, by gender, extent of disease, relapse and age-matching variables, was performed between the two groups, resulting in 20 paired matches. This prospective study was planned as an unblinded, non-randomized quasiexperimental pilot project. Outcomes were identified from results of sputum smear examinations for AFB in both groups at 2 weeks, and 1 and 2 months. The paired matching data were analyzed using the SAS program version 8.1 by McNemar test. Results : At the end of 2 weeks of treatment, the sputum smear conversion of the mDOT group was somewhat higher than that of the self medication group (78.57 vs. 50%, p-value=0.289), and after 1 month of treatment no statistically significant difference was shown between the two groups (83.33 vs. 50, p-value=0.125). At the end of 2 months of treatment (initial intensive phase), the sputum smear conversions of the mDOT and self groups were 95 and 75%, respectively (p-value=0.219). Conclusions : The implementation of mDOT did not result in clinically significant increases in the sputum smear conversion at 2 weeks, and 1 and 2 months compared with that of the self medication group. However, the increases experienced might contribute to diminishing the infectious period of AFB positive patients, and this approach may act as a guide for a specific group of patients. In this study, mDOT was performed for one hundred percent of the intensive treatment phase. It can also be an effective treatment for pulmonary tuberculosis patients, and may be useful for some high risk tuberculosis patients.

• The Korean Journal of Nuclear Medicine
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• v.1 no.1
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• pp.37-54
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• 1967

The changes in histopathology of various organs and growth inhibition of the chick embryos incubated with radioactive sulfur ($^{35}S$) were experimentally studied. The various doses of $^{35}S$ were injected into the yolk sac at different intervals and the weight changes of the embryos were evaluated to determine the growth inhibition rates. The embryos sacrified on various incubation days were used for the study of histopathological changes in organs such as the bone, liver, kidney, gonad, and eye. Following were the results: 1) The weight changes of the $^{35}S$ treated groups were as follows: i. Embryos treated on the 5 th incubation day: No weight changes were noted on the 8th incubation day, however, the growth inhibition rate of 32.1% was noted in the group treated with $50{\mu}C$ and of 38.2% in the group treated with $150{\mu}C$ on the 12th incubation day. The rates were 9.1 and 12.1% on the 15th incubation day, and 6.5 and 10.6% on the 18th incubation day respectively. ii. Embryos treated on the 8th incubation day: The growth inhibition rates on the 12th, 15th and 18th incubation days in the groups treated with $50{\mu}C$ were 20.9, 25.9 and 18.8% and in those treated with $150{\mu}C$ were 20.0, 14.9 and 16.9% respectively. iii. Embryos treated on the 12th incubation day: The growth inhibition rates on the 15th and 18th in the groups treated with $50{\mu}C$ were 13.6 and 21.1% and in those treated with $150{\mu}C$ were 26.7 and 6.5% and in those treated with $250{\mu}C$ were 10.6 and 12.6% respectively. iv. Embryos treated on the 15th incubation day: The growth inhibition rates on the 18th in the groups treated with $50{\mu}C$ were 6.5% and in those treated with $150{\mu}C$ were 10.1% and in those treated with $250{\mu}C$ were 8.5% respectively. In summary, the longer the incubation days, the less the growth inhibition rates. II) The histopathological changes in the various organs were as follows: i. Bone: Hyperplasia and edematous changes of the bone cavity, irregular distribution of immature granular cells and increased number of the myeloblast, megakaryocyte and reticuloendothelial cells were noted. ii. Liver: The embryos treated with $150{\mu}C\;of\;^{35}S$ on the 8th incubation day showed necrosis and nucleolysis of the liver cell and abnormal enlargement of sinusoid on the 12th incubation day. The longer the incubation days, the more severe the changes such as the pyknotic artophy of the liver cells and heterochromatism. The embryos treated on the 5th incubation day with 50 and $150{\mu}C\;of\;^{35}S$ showed little changes, but sight enlargement and accumulation of serous fluid in the sinusoid on the 8th incubation day. iii. Kidney: No particular changes except atrophic changes of epithelium were noted in early stage, however, the infiltration of the granular cell and monocyte into the cortex and pyknotic changes of vascular glomeruli were noted in later stage. These changes were not closely related to the doses of $^{35}S$ given. iv. Gonad: The degenerative changes such as destruction of the immature germ cells, hyperplasia and vacuolization of the stroma were noted in testis and ovary. v. Eye: A slight distortion of the cornea and sclera was noted. The hypertrophy of inner layer and blood cell infiltration into the vascular layer of the choroid membrane were noted in embryo groups on the 12, 15 and 18th incubation days.

• The Korean Journal of Nuclear Medicine
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• v.20 no.2
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• pp.85-100
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• 1986

To evaluate the clinical and pathogenetic roles of TSH receptor antibodies in autoimmune thyroid diseases, TBII were measured by TSH-radioreceptor assay methods in 352 patients with Graves' disease, 108 patients with other thyroid diseases and 69 normal persons. The normal range of TBII activity was less than 15%. The frequencies of detectable TBII in 169 patients with untreated Graves' disease, 31 patients with hyperthyroidism under treatment and 70 patients with euthyrodism under treatment were 92.4%, 87.1% and 54.3% respectively. However 12 (21.8%) out of 55 patients who have been in remission more than one year after discontinuation of antithyroid drugs treatment had detectable TBII activities in their sera. In 196 patients with untreated Graves' disease, the frequency of TBII increased by increasing size of goiter and the frequency of proptosis was significantly high in patients whose TBII activities were more than 60%. TBII activities were roughly correlated with total $T_3,\;T_4$ and free $T_4$ index but low $\gamma^2$ value(less than 0.1). In 67 patients with Graves' disease who were positive TBII before antithyroid drugs treatment, TBII activities began to decrease from the third months and it was converted to negative in 35.8% of patients at 12 months after treatment. There were no significant differences of the declining and disappearing rates of TBII activities between high dose and conventional dose groups. TBII activities were significantly increased initially (2-4 months) and then began to decrease from 5-9 months after $^{131}I$ treatment. There were two groups, one whose TBII activities decreased gradually and the other did not change untill 12 months after subtotal thyroidectomy. Although preoperative clinical and laboratory findings of both groups were not different, TBII activities of non-decreasing group were significantly higher than those of decreasing group$(74.6{\pm}18.6%\;vs\;39.2{\pm}15.2%;\;P<0.01)$. Thirty three(55.9%) out of 59 patients with Graves' disease relapsed within 1 year after discontinuation of antithyroid drugs. The positive rate of TBII at the end of antithyroid drug treatment in relapse group(n=33) was significantly higher than those in remission group (n=26) (63.6% vs 23.1%; P < 0.05). The mean value of TBII activities at the end of antithyroid drug treatment in relapse group was significantly elevated $(29.7{\pm}21.4%\;vs\;14.7{\pm}11.1%,\;P<0.05)$. Positive predictive value of TBII for relapse was 77.8%, which was not different from those of TRH nonresponsiveness(78.6%). The frequencies of detectable TBII in 68 patients with Hashimoto's thyroiditis, 10 patients with painless thyroiditis and 5 patients subacute thyroiditis were 14.7%, 20% and 0%, respectively. However in 25 patients with primary nongoitrous myxedema, 11 patients(44%) showed TBII activities in their sera. 9 out of 11 patients who had TBII activities in their sera showed high TBII activities(more than 70% binding inhibition) and their IgG concentrations showing 50% binding inhibition of $^{125}I-bTSH$ to the TSH receptor were ranges of 0.1-2.6 mg/dl. One patient who had high titer of TBII in her serum delivered a hypothyroid baby due to transplacental transfer of maternal TBII. These findings suggested that 1) TSH receptor antibodies are closely related to a pathogenetic factor of Graves' hyperthyroidism and of some patients with primary non-goitrous myxedema, 2) measurement of TSH receptor antibodies is helpful in evaluating the clinical outcome of patients with Graves' disease during antithyroid drug treatment and in predicting the neonatal transient hypothyroidism of baby delivered from primary myxedema patients. 3) there are 2 or more different types of TSH receptor antibodies in autoimmune thyroid diseases including one which stimulates thyroid by binding to the TSH receptor and another which blocks adenylate cyclase stimulation by TSH.

• Journal of Chest Surgery
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• v.30 no.3
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• pp.287-292
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• 1997

.Itrial fibrillation is one of the most common cardiac arrhythmias requiring treatment. About 60% of patients with mitral valvular disease have atrial fibrillation and one third of patients with atrial fibrillation may have the past history of thromboembolic events. Between April 1994 and June 1995, 20 patients with organic heart diseases combined with atrial fibrillation underwent open heart surgery including Cox-maze 111 procedure. There were 6 men and 14 women with an average age of 48 years (range, 31 to 66 years). Nineteen patients had valvular heart diseases and 1 ventricular septal defEct (VSD). Mean duration of atrial fibrillation was 36 months (:42 months) (range, 1 to 132 months). T e past medical history of thromboembolic events was positive in 7 patients (35%) and left atrial thrombus was detected in 9 patients (45%). The concomitant procedures were mitral valve replacement (MVR) and aortic valve replacement (AVR) in 5 patients, MVR in 4, MVd and tricuspid annuloplasty(TAP) in 4, mitral valvuloplasty(Mln) in 3, Mln and Tln in 1, MIW and coronary artery bypass surgery in 1, AVR in 1, and patch closure of VSD in 1. Mean aortic cross-clamping time was 175 minutes (range, 116 to 270 minutes). Atrial fibrillation recurred in 16 patients (80%) during the early postoperative period, but, recurrent atrial fibrillation was converted to regular rhythm at postoperative forty-first day in average. There was no early or late death in this series of 20 patients and postoperative complications were inappropriate tachycardia in 5 patients (25%), low cardiac output syndrome in 3 (15%), aggravated hemiplegic in 1, and acute renal failure in 1. Mean follow-up interval of patient was 16.5 months (range, 10.5 to 24 months) and all patients are currently in regular rhythm. Seventeen patients (85%) are in sinus rhythm and 3 (15%) in junctional rhythm. Right atrial contraction was detected in 95% of patients and left atrial contraction in 63% on postoperative transthoracic echocardiogram. The surgical treatment of atrial fibrillation concomitant with open heart surgery is warranted in the recent clinical setting of improved myocardial protection technique, considering the untoward side-effects of atrial fibrillation.