실외용 절연 재료 개발을 위한 에폭시 복합재료의 망목 구조 개질에 관한 연구

김재환,손인환,김탁용 광운대학교 신기술연구소 1997 신기술연구소논문집 Vol.26 No.-

옥외용 절연재료를 개발하기 위하여, 에폭시 수지에 SIN(상호침입망목) 구조를 도입하여 내환경성을 연구하였다. 단일망목 시편(E 계열)은 에폭시 수지로만 제작하였고, 상호침입망목 시편(EM 계열)은 일차망목으로 에폭시 수지, 이차 망목으로 메틸메타아크릴수지로서 제작하였다. 충진제 함량에 따라 10종의 시편을 제작하여, 시편의 망목구조 변화를 확인하기 위하여 주사전자 현미경으로 내부 구조를 관찰하였다. 그리고 교류전압절연파괴강도를 측정하였다. 또한, 내환경성을 측정하기 위하여 자외선 조사 실험과 트래킹 실험을 하였다. 그 결과, 내부 구조의 변화를 확인할 수 있었고, 상호침입망목 구조 시편이 단일망목 시편보다 내환경성이 우수함을 확인하였다. In order to develop outdoor insulating materials, SIN(simultaneous interpenetrating polymer network) was introduced to epoxy resin and the environment resistance was investigated. The single network structure specimen(E series) formed of Epoxy resin alone and simultaneous interpenetrating polymer network specimen (EM series) in which epoxy resin was taken as the first network and methyl methacrylate resin as the second network were manufactured. Ten kinds of specimens were manufactured by filler (SiO_2) content. SEM were utilized in order to confirm their network structure changes, and AC voltage dielectric strength was measured. Also, UV-test and tracking test were carried out to investigate the environment resistance characteristic. Therefore the variations of network structure were happened as a result of SEM test, and it was confirmed that simultaneous interpenetrating polymer network specimens were more excellent than single network structure specimens.

의식이 명료한 경증 두부 외상환자에서 뇌 전산화단층촬영의 의의

허탁,김성근,민용일 大韓應急醫學會 1997 대한응급의학회지 Vol.8 No.1

A standardized approch to serious head injury employing immediate CT scanning and aggressive medical and surgical therapy has improved outcomes in cases of intracranial lesions. Unfortunately, there is less agreement on how patients with mild head injury should be handled when first seen in an emergency department setting. The ideal policy in mild head injury would be diagnosis or rule-out intracranial lesions as quickly as possible. We reviewed the records of 126 mild head injury patients admitted during 6-month period to the Chonnam University Hospital to identify a group of mild head injury patients having lesions on brain CT scanning and to investigate the risk factors affecting abnormal lesions on brain CT scanning. All patients had alert mental status without neurological deficit and signs of skull fracture. Routine brain CT scans were obtained on all patients. Fifteen patients(12%) had 17 lesions on brain CT scans. Three patients needed surgery for their intracranial lesions. The initial Glasgow Coma Scale(GCS) was 15 in 107 patients and 14 in 19 patients. The incidence of abnormal brain CT lesions for each GCS was 9% in 15 and 26% in 14. The common symptoms of patients who had abnormal brain CT lesions were headache in 7(47%) cases, loss of consciousness in 7(47%) cases, amnesia in 4(27%) cases, dizziness in 4(27%) cases, vomiting in 3(20%) cases, and lethargy in 3(20%) cases. These data suggest that early brain CT scanning is necessary in alert patients who have GCS in 14, headache, loss of consciousness, amnesia, dizziness, vomiting, or lethargy following mild head injury.

경추손상이 의심되는 환자에서 경추전방 연부조직 폭 측정의 의의

박주경,김성근,윤한덕,허탁,조석주,민용일 대한응급의학회 1995 대한응급의학회지 Vol.6 No.2

Prevertebral soft tissue swelling of cervical spine lateral radiogram is well known as an indirect evidence of occult cervical spine injury. But the clinical and statistical value of it has been of debate. We tried to analyse the value of cervical prevertebral soft tissue width as a screening test for cervical spine injury by comparison of two categorized study groups; the control group, traumatized patients without cervical spine injury and the injury and the injury group, traumatized patients with bony cervical injury. The injury group consisted of patients admitted between September 1993 and December 1994 with an ED diagnosis of bony cervical injury. The control group consisted of patients admitted between January 1994 and June 1994 who received cervical spine lateral radiograph because of suspicion of cervical spine injury or as a routine check. In both group, we sampled the patients who received cervical spine lateral rediograph within 24 hours after injury and excluded the patients less than 15 years old and more than 65 years old, In the control group, we confirmed the patients had no problem in cervical spine of follow-up. 101 control patients and 68 injury patients were identified. The injury group was further divided into two subgroups: those with injuries at C1-C3 to the upper injury subgroup and those with injuries at C4-C7 to the lower injury sub group. The prevertebral soft tissue widths of injury group were larger than of control group at C2(mean 6.1mm versus 4.5mm) and also at C6(mean 13.4mm versus 11.2mm). Especially upper injury subgroup had quite large value of C2 prevertebral soft tissue width(mean 14.1mm). Nevertheless, both in C2 and C6, there is no cutoff value with acceptable sensitivity and specificity as a screening test. But the 7mm at C2 and 14mm at C6 had high specificity(90%) and were thought to be a good radiologic indicators of further evaluation.

휴통과 ST분절상승을 보이는 환자에서 급성심근경색증과 비심근경색증의 심전도 분석

류진호,김용권,소정일,허탁,민용일 대한응급의학회 2000 대한응급의학회지 Vol.11 No.4

Background: ST segment elevation in patient with chest pain was seen in acute myocardial infarction and in numerous other non-infarction syndromes. The causes of non-infarction syndrome were left ventricular hypertrophy, BER(benign early repolarization), and left bundle branch block in cardiac origin and were hyperkalemia and hyperventilation syndrome in metabolic origin and were others. Furthermore, the differentiation of electrocardiogram between acute myocardial infarction and non-infarction syndrome was very difficult. So, we compared and analysed characteristics of ST segment elevation of acute myocardial infarction and non-infarction syndrome that suggested the clue of early diagnosis of coronary artery disease. Method and Materials: We retrospectively reviewed the electrocardiogram of 961 patients with chest pain who visited the emergency center from January 1999 to December 1999. Acute myocardial infarction was diagnosed by clinical finding, electrocardiogram, cardiac enzyme, echocardiogram, and myocardial spect. Left ventricular hypertrophy, BER, and left bundle branch block in cardiac origin of non-infarction syndrome were diagnosed by electrocardiographic criteria suggested by William J. Brady. Acute myocarditis, acute pericarditis, and hyperventilation syndrome were diagnosed by clinical finding. Results: Among 961 patients with chest pain, 236(24.6%) patients manifested ST segment elevation who were diagnosed acute myocardial infarction in 162(68.6%) patients and non-infarction syndrome in 74(31.4%) patients. The causes of non-infarction syndrome in 74 patients were left ventricular hypertrophy(32:13.6%), BER(28:11.9%), left bundle branch block(11:4.7%), and others(3:1.3%). Three others were acute myocarditis, acute pericarditis, and hyperventilation syndrome. Electrocardiographic characteristics of ST segment elevation of non-infarction syndrome manifested almost same finding compared to William J. Brady' criteria. Conclusion: ST segment elevation in patient with chest pain visited emergency department was seen in acute myocarction(68.6%) and the other non-infarction syndromes(31.4%). Significant number of patients were not associated with acute myocardial infarction. Therefore, we must completely understand characteristics of ST segment elevation in acute myocardial infarction and the other non-infarction syndreomes to diagnose fatal early coronary artery disease and to avoid unnecessary thrombolytic therapy.

외상 후 뇌 지방색전증 1예

문정미,소정일,김용권,류진호,허탁,서정진,민용일 대한응급의학회 2001 대한응급의학회지 Vol.12 No.2

Post-traumatic fat embolism was first reported by Zenker in 1862, Von Bergmann reported the first clinical diagnosis of the fat embolism syndrome in 1873. Fat embolism has been associated with traumatic or non-traumatic disorders. Fat embolization after long bone trauma is probably common as a subclinical event. The diagnosis of fat embolism syndrome is based on the patient's history, is supported by clinical signs of pulmonary, cerebral, and cutaneous dysfunction, and is confirmed by the demonstration of arterial hypoxemia in the abscence of other disorders. Two different mechanisms cause fat to embolize: direct entry of deposit fat into the blood stream and agglutination of endogenous or exogenous plasma fat. MRI can detect a cerebral fat embolism with a higher sensitivity than cerebral CT. We report a case of post-traumatic cerebral fat embolism without pulmonary involvement, and we present a review of the literature. A 16-year girl had a traffic accident and pelvic bone fracture. Forty eight hours later severe trauma become stuporous without a focal neurological deficit. The patient received supportive therapy, and her condition improved throughout her hospital course. She was discharged with good condition after a 30-day hospital stay.

급성췌장염을 동반한 특발성 양측성 횡격막 마비 1례

박주경,소정일,류진호,김성근,허탁,민용일 大韓應急醫學會 1998 대한응급의학회지 Vol.9 No.4

Bilateral diaphragmatic paralysis(BDP) is a rare disorder, which can be secondary to spinal cord injury, motor neuron disease, myopathy, noninfectious polyneuropathy, infection, iced saline cardioplegia performed during cardiac surgery, or idiopathic causes. There may be typical presentations such as dyspnea, paradoxical respiratory movement, and hypercapnic respiratory failure. It needs to exclude above secondary causes to consider idiopathic bilateral diaphragmatic paralysis. We report a 51-years-old man who presented with idiopathic bilateral diaphragmatic paralysis combined with acute pancreatitis. We couldn't find out the association of these two clinical conditions. The patient was improved by mechanical ventilation.

신손상 진단에 있어 현미경적 혈뇨의 의의

임정환,오봉렬,나국주,김현수,윤한덕,허 탁,조석주,민용일 大韓應急醫學會 1996 대한응급의학회지 Vol.7 No.1

The evaluation of patients with microscopic hematuria after blunt abdominal trauma has become controversial. We tested the hypothesis that renal contusion can be diagnosed clinically and that these patients do not require radiographic evaluation. To evaluate the association of microscopic hematuria without shock and with renal injury, we reviewed the medical records of 252 patients following blunt abdominal trauma. Microscopic hematuria without shock was noted in 58 of 252 patients. Of the 58 patients 52 had renal contusion, 4 had renal laceration, 1 had a renal rupture and 1 had renal pedicle injury. All of the patients with renal contusions experienced no complications from nonoperative management. But, avoiding a radiopraphic evaluation in patients with blunt renal trauma plus microscopic hematuria and no shock would miss a few cases of severe renal injury.

소화관내 이물에 대한 고찰

윤한덕,류진호,박주경,허탁,조석주,김성근,민용일 大韓應急醫學會 1997 대한응급의학회지 Vol.8 No.1

We analyzed records at Chonnam university hospital from Sep. 1. 1993 to Aug. 31. 1996 to assess clinical significance of the foreign body in the gastrointestinal tract. There were 133 episodes consisting of 79 pediatric and 54 adult patients as possible to review. In the pediatric patients, the coin was the most common cause of foreign body ingestion, while adult patients were usually caused by bones and meat. We removed foreign bodies in the oral cavity and oropharynx in 12 cases using direct laryngopharyngoscpy and forcep. Endoscopy was performed successfully in 47 of 51 patients in which was attempted; there were two complications composed of an aspiration pneumonia and a mediastinitis due to esophageal perforation. There were spontaneous passage of foreign bodies in 48 cases. We observed complications in 6 cases in which 4 cases needed operations due to complications. Foreign bodies which pass into the stomach can be observed for development of complications, as 94% of foreign bodies which reach the stomach spontaneously pass. Only 4 patients required interventions, which was done without mortality.

3차 병원의 병동에서 시행된 심폐소생술의 분석

류진호,정경운,위준선,문정미,전병조,문원식,김용권,소정일,허탁,민용일 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Background: Although cardiopulmonary resuscitation(CPR) is a very effective therapy in cardiac arrest, it is hard to prove the true effectiveness of CPR. Several studies about out-of-hospital and emergency department CPR exist, but only a few reports about in-hospital CPR are available. This study was designed to investigate in-hospital cardiac arrest, to analyze the result of CPR, and to evaluate the problems associated with in-hospital CPR. Methods: A clinical analysis of 71 cases of in-hospital CPR announcement from January 2000 to August 2000 was performed. The initial rhythm on cardiac arrest, return of spontaneous circulation(ROSC), and the survivals were analyzed in the case of the 46 true cardiac arrest patients. Results: During 8 months, there were 71 cases of in-hospital CPR announcement. Among them, there were 46 cases of true cardiac arrest and 25 cases of non-cardiac arrest. Of the 46 true cardiac-arrest cases, 27(58.7%) experienced ROSC, 15(32.6) survived for over 24 hours, and 7(15.2%) survived to be discharged. The initial rhythms on cardiac arrest were 30 cases(65.2%) of asystole, 14(30.4%) of PEA(pulseless electrical activity), and 2(4.3%) of ventricular fibrillation, with ROSC being 17 cases(56.7%), 9(64.3%) and 1(50.0%) cases and discharged survivors being 4 cases(13.3%), 3(21.4%) and 0(0.0%) cases, respectively. Conclusion: Extraordinarily high proportions of asystole and PEA were seen in the initial rhythm of cardiac arrest, and those were associated with high survival rates. Although further study is needed to evaluate the course leading to this high proportion of asystole and PEA, this result suggests that if the EMS system in the hospital is activated promptly and systematically, a better outcome will be achieved in case of cardiac arrest with asystole and PEA.

응급실에 내원한 환자에서 어지럼증의 원인과 임상양상의 분석

문원식,정경운,위준선,문정미,전병조,김용권,소정일,류진호,허탁,민용일 대한응급의학회 2001 대한응급의학회지 Vol.12 No.3

Background: Recently, The number of patients who have been complaining of the vertigo or dizziness has been increasing due to rapid growth of elderly population and senile disease. The differentiation of dizzy patients is not familiar to most emergency physicians. This study was designed to differentiate true vertigo and to investigate the clinical difference among central vertigo, peripheral vertigo, and other causes of dizziness. Methods: The authors analyzed the cases of 237 dizzy patients who visited the emergency department of Chonnam University Hospital during the recent 2 years. For the base of dizziness, associated past illnesses, severity, nystagmus type, and the causes of central and peripheral vertigo. Results: Female patients were 142(59.9%) and male patients were 95(40.1%). The most common age group was the 6th decade. The origin of dizziness was classified as peripheral cause(25.3%), central cause(32.9%), and others(41.8%). As to nature of the dizziness, the rotatory sense was dominant in peripheral vertigo and the floating sense and blurred vision in central vertigo. Peripheral vertigo was triggered by position change of head and body, and central vertigo by the eye movement. Audiograms I showed that most patients with central vertigo had normal hearing, but 46.7% of thoswith peripheral vertigo had an abnormal hearing disturbance. Nystagmus was more prevalent in peripheral vertigo Conclusion: History taking and physical examination played an important role in the diagnosis of dizzy patients. An important part of the diagnosis of a dizzy patient could be to evaluate the peripheral origin, the central origin and others causes. Because central vertigo may be associated with a significant neurological pathology, spectral radiological studies, including MRI and CT, are mandatory to rule out a devastating brain lesion.