This study investigated the human health risks of trichloroethylene from Industrial Complex A. The excessive carcinogenic risks for central tendency exposure were 1.40 x 10(-5) for male and female residents in the vicinity of Industrial Complex A. The excessive cancers risk for reasonable maximum exposure were 2.88 x 10(-5) and 1.97 x 10(-5) for males and females, respectively. These values indicate that there are potential cancer risks for exposure to these concentrations. The hazard index for central tendency exposure to trichloroethylene was 1.71 for male and female residents. The hazard indexes for reasonable maximum exposure were 3.27 and 2.41 for males and females, respectively. These values were over one, which is equivalent to the threshold value. This result showed that adverse cancer and non-cancer health effects may occur and that some risk management of trichloroethylene from Industrial Complex A was needed.
Female ; Humans ; Male ; Risk Assessment ; Risk Management ; Trichloroethylene ; Volatile Organic Compounds

Hazardous area classification design is required to reduce the explosion risk in process plants. Among the international design guidelines, only IEC 60079-10-1 proposes a new type of zone, namely zone 2 NE, to prevent explosion hazards. We studied how to meet the zone 2 NE grade for a facility handling hydrogen gas, which is considered as most dangerous among explosive gases. Zone 2 NE can be achieved considering the grade of release, as well as the availability and effectiveness of ventilation, which are factors indicative of the facility condition and its surroundings. In the present study, we demonstrate that zone 2 NE can be achieved when the degree of ventilation is high by accessing temperature, pressure, and size of leak hole. The release characteristic can be derived by substituting the process condition of the hydrogen gas facility. The equations are summarized considering relation of the operating temperature, operating pressure, and size of leak hole. Through this relationship, the non-hazardous condition can be realized from the perspective of inherent safety by the combination of each parameter before the initial design of the hydrogen gas facility.

Hazardous area classification design is required to reduce the explosion risk in process plants. Among the international design guidelines, only IEC 60079-10-1 proposes a new type of zone, namely zone 2 NE, to prevent explosion hazards. We studied how to meet the zone 2 NE grade for a facility handling hydrogen gas, which is considered as most dangerous among explosive gases. Zone 2 NE can be achieved considering the grade of release, as well as the availability and effectiveness of ventilation, which are factors indicative of the facility condition and its surroundings. In the present study, we demonstrate that zone 2 NE can be achieved when the degree of ventilation is high by accessing temperature, pressure, and size of leak hole. The release characteristic can be derived by substituting the process condition of the hydrogen gas facility. The equations are summarized considering relation of the operating temperature, operating pressure, and size of leak hole. Through this relationship, the non-hazardous condition can be realized from the perspective of inherent safety by the combination of each parameter before the initial design of the hydrogen gas facility.

Background: According to the previous studies, the work-related accident rate decreased in Korea after the introduction of occupational health and safety management system (OHSMS), but there were several disasters in Korea such as subway worker's death at Guui station in 2016 and the Taean thermal power plant accident in 2018, which escalated the social demand for safety. In 2018, OHSMS became an international standard, as ISO45001 was announced. Methods: A survey was conducted to research the implementation status of OHSMS and changes in people's perception, and the results were compared with those of a past survey. Results: Enhanced social demand and various stakeholders' (not only buyer) needs, and social responsibility are perceived as the motivation for the introduction of OHSMS rather than legal compliance or customer demand. In the questionnaire about problems with the implementation of OHSMS, the factors with higher response rate in 2018 than 2004 were “excessive cost” and “complicated documentation management.” In the questionnaire about how to promote OHSMS in organizations, most people answered “reduction of workers' compensation insurance rate” in 2004, but most people answered “exemption from health and safety supervision” in 2018. Conclusion For the effective implementation of ISO45001, emphasis is placed on social demand, training to recognize health and safety as a part of management, and the reduction of certification and consulting costs to promote the introduction of OHSMS. Incentives such as insurance premium cuts and exemptions from health and safety supervision are needed.

Background: According to the previous studies, the work-related accident rate decreased in Korea after the introduction of occupational health and safety management system (OHSMS), but there were several disasters in Korea such as subway worker's death at Guui station in 2016 and the Taean thermal power plant accident in 2018, which escalated the social demand for safety. In 2018, OHSMS became an international standard, as ISO45001 was announced. Methods: A survey was conducted to research the implementation status of OHSMS and changes in people's perception, and the results were compared with those of a past survey. Results: Enhanced social demand and various stakeholders' (not only buyer) needs, and social responsibility are perceived as the motivation for the introduction of OHSMS rather than legal compliance or customer demand. In the questionnaire about problems with the implementation of OHSMS, the factors with higher response rate in 2018 than 2004 were “excessive cost” and “complicated documentation management.” In the questionnaire about how to promote OHSMS in organizations, most people answered “reduction of workers' compensation insurance rate” in 2004, but most people answered “exemption from health and safety supervision” in 2018. Conclusion For the effective implementation of ISO45001, emphasis is placed on social demand, training to recognize health and safety as a part of management, and the reduction of certification and consulting costs to promote the introduction of OHSMS. Incentives such as insurance premium cuts and exemptions from health and safety supervision are needed.

OBJECTIVE: The authors undertook a study to compare three intraoperative guidance systems, which are intraoperative ultrasonography, stereotaxy and computer-assisted image-guided surgery (neuronavigation) in terms of time consuming during the preparation of these procedures. In this operative case-based study, we have investigated the ability and benefits of intraoperative grey-scale sonographic examination in the localizing of intracranial hemorrhage (ICH) in the brain. METHODS: We used B-mode ultrasonography (5-MHz, 1.2x2.5 mm sized probe) during 23 procedures (craniotomy or craniectomy ; 17, hematoma aspiration : 6) performed in the acute stage after head injury, hypertensive ICH, ruptured cerebral aneurysm. Seventeen patients who suffered from spontaneous ICH underwent stereotactic hematoma aspiration and fourteen patients underwent hematoma removal using neuronavigation system (spontaneous ICH ; 11, Arteriovenous malformation and aneurysm ; 3). We compared intraoperative ultrasonography-assisted hematoma removal with procedures with stererotaxy or neuronavigation system in respect of detection of the pathology and time consuming for preparation. RESULTS: Mean preparation time for stereotactic hematoma aspiration was 71.2 minutes (50-90 minutes), and mean preparation time for neuronavigation-guided surgery was 52.5 minutes (30-70 minutes). However, only 7.4 minutes (4-20 minutes) were needed for the preparation time of intraoperative ultrasonography. Moreover, intraoperative ultrasonography-guided surgery had many advantages compared to other image-guide surgery, such as capability of real-time monitoring and independency of brain shifting. However, there were several limitations too, which were relatively low resolution, artifact by air bubble during the procedure, and the lower echogenecity of liquified hematomas when a delay of several days was needed. Nevertheless, ultrasound-guided hematoma surgery could serve as minimally invasive treatment whenever hematoma evacuation seems to be advisable, at least as a first attempt. CONCLUSION: Based on this preliminary result, we concluded that intraoperative ultrasonographic examination during the surgical treatment of ICH was a non-invasive, useful, and simple diagnostic tool in the detection of the components and accompanying parts of the lesion. It was more useful than stereotaxy or neuronavigation system in the situation of emergent case such as an impending brain herniation.
Aneurysm ; Arteriovenous Malformations ; Artifacts ; Brain ; Cerebral Hemorrhage* ; Craniocerebral Trauma ; Hematoma ; Humans ; Intracranial Aneurysm ; Intracranial Hemorrhages ; Neuronavigation ; Pathology ; Surgery, Computer-Assisted* ; Ultrasonography*

BACKGROUND: Infusion methods during regional analgesia using perineural catheters may influence the quality of postoperative analgesia. This study was conducted to compare the effects of combined or bolus-only infusion of 0.2% ropivacaine on the postoperative analgesia in interscalene brachial plexus block (ISBPB) with perineural catheterization. METHODS: Patients scheduled for arthroscopic rotator cuff repair were divided into two groups, one that would receive a combined infusion (group C, n = 32), and one that would receive intermittent infusion (group I, n = 32). A perineural catheter was inserted into the interscalene brachial plexus (ISBP) using ultrasound (US) and nerve stimulation, and 10 ml of 0.2% ropivacaine was administered. After the operation, group C received a continuous infusion of 4 ml/h, and a 4 ml bolus with a lockout interval of 60 min. Group I received only a 4 ml bolus, and the lockout interval was 30 min. Postoperative pain by the numeric rating scale (NRS) and the forearm muscle tone by the manual muscle test (MMT) were checked and evaluated at the following timepoints: preoperative, and postoperative 1, 4, 12, 24, 36, and 48 h. Supplemental opioid requirements, total consumed dose of local anesthetic, and adverse effects were compared between the two groups. RESULTS: Sixty-four patients completed the study and the postoperative values such as operation time, time to discharge, and operation site were comparable. There were no differences in NRS scores and supplemental opioid requirements between the two groups. The MMT scores of group I at 4 and 12 h after surgery were significantly higher than those of group C (P < 0.05). The total consumed dose of local anesthetic was significantly lower in group I than in group C (P < 0.05). The adverse effects were not different between the groups. CONCLUSIONS: The bolus-only administration of 0.2% ropivacaine provided a similar analgesic effect with a lower total volume of local anesthetic and decreased motor weakness compared to combined infusion. Therefore, bolus-only administration is an effective postoperative analgesic method in ISBPB with perineural catheterization after rotator cuff repair.
Analgesia ; Analgesia, Patient-Controlled ; Arthroscopy ; Brachial Plexus* ; Catheterization ; Catheters ; Forearm ; Humans ; Pain, Postoperative* ; Rotator Cuff* ; Ultrasonography

Intramucosal colorectal cancer (CRC) is thought not to metastasize because the colonic lamina propria lacks lymphatics. Only a few recent case reports have suggested lymph node metastasis from intramucosal CRC, but there is no clear evidence supporting the metastatic potential of intramucosal CRC. Hence, endoscopic resection is regarded as curative treatment for intramucosal CRC. This report describes two cases of unusual local recurrence with distant metastasis in patients who had previously undergone successful endoscopic submucosal dissection for intramucosal CRC. The recurrent colorectal lesions developed at the site of the previous endoscopic submucosal dissection scars in a relatively short-term period, and the pathologic findings showed an “undermining” invasion pattern without surrounding mucosal change. Based on the clinical course and pathological findings, we concluded that the second colorectal lesions were recurrences rather than de novo cancers.
Cicatrix ; Colon ; Colorectal Neoplasms ; Humans ; Lymph Nodes ; Mucous Membrane ; Neoplasm Metastasis* ; Recurrence*

BACKGROUND/AIMS: Endoscopic mucosal resection with circumferential mucosal incision (CMI-EMR) may offer benefits comparable to those of endoscopic submucosal dissection (ESD), while requiring less technical proficiency than ESD. METHODS: We retrospectively compared the outcomes of CMI-EMR (n=34) and size-matched ESD (n=102), which were performed by a Korean endoscopist for colorectal epithelial lesions of 20–35 mm. Procedural parameters of CMI-EMRs performed by an American ESD novice (n=30) were compared with those performed by the Korean endoscopist. RESULTS: The lesion size was 22.3±3.9 mm and 22.9±2.4 mm in the CMI-EMR and size-matched ESD groups, respectively (p=0.730). The resection time was 12.7±7.0 minutes in the CMI-EMR group and 45.6±30.1 minutes in the ESD group (p<0.001). The en bloc resection rate was 94.1% in the CMI-EMR group and 100% in the ESD group (p=0.061). There were no differences in the en bloc resection and complication rates of CMI-EMRs between a Korean and an American endoscopist. CONCLUSIONS: For the treatment of moderate-size colorectal lesions, CMI-EMR showed a trend toward lower en bloc resection rate, but required shorter procedure time than ESD. CMI-EMR outcomes were similar when performed by a Korean ESD expert and an American ESD novice.
Colon ; Colorectal Neoplasms* ; Rectum ; Retrospective Studies

BACKGROUND: The previous studies suggested that the rate of the people who reported having sensitivity to cold and Raynaud's disease were 12% and 5~10% of general population respectively. There are surprisingly few data on 'cold hands and feet syndrome', the conventional circulatory disorder in far-eastern Asia in spite of the assumption that it is a common disorder among Korean population. Besides, the prevalence of Raynaud's disease has not been studied for Korean complaint of the syndrome. Therefore, we conducted the survey regarding the frequency of Baynaud's disease and phenomenon among the people appealed abnormal sensory symptoms on hands and feet, and 'cold hands and feet syndrome'. METHODS: The questionnaires were asked to 1,008 out- patients who complained abnormal sensory symptoms on hands and feet. The subjects were screened among the patients who visited the clinics, mainly department of family medicine in Uijongbu St. Mary's hospital from January to July 2003. RESULTS: The most common abnormal sensory symptoms were tingling feeling and coldness, pain in the descending order. The mean age of the patients is 47 years, the average age at the onset of the symptoms is 40 years, and the mean duration they had been suffered by the symptoms is 7 years. During interview, 289 patients voluntarily appealed 'cold hands and feet syndrome' in expression of "I have cold extremities" or "I have the syndrome". Among the screened patients, 510 patients answered, "yes" to the question "Are your fingers unusually sensitive to cold?" Two hundred and nineteen patients (43%) of them showed Raynaud's phenomenon. One hundred and sixty patients were diagnosed as Raynaud's disease among 219 patients who had Raynaud's phenomenon. The rest 59 patients were diagnosed as secondary Raynaud's phenomenon. Eighty-seven patients (30%) of 289 patients who voluntarily reported 'cold hands and feet syndrome' were diagnosed as Raynaud's disease. The average age of Raynaud's disease patients is 37 years old, average first attack age is 24 years, and average suffering period is 14 years. Only 10% of cases experienced the first attacks after 40 years old. The attack rates are different by gender. The ratio is 2.3 and higher in female. Only six patients (4%) of Raynaud's disease had been diagnosed accurately. Fifty-three patients (33%) have family history and 41 of them are the first-degree relatives. The causes of secondary Raynaud's phenomenon (59 patients) are connective tissue disorders, neurologic diseases, carpal tunnel syndrome, hypothyroidism, vascular disorders, etc. The statistically significant factors that influence on Raynaud's disease are female, below 40 years old, stress, family history, hypertension, diabetes, etc. The statistical analysis in this study does not prove the association between the disease and the factors such as physical labor, manual labor using hands heavily, smoking, drinking, thyroid diseases, joint disorders, ischemic heart disease, depression. CONCLUSION: Raynaud's disease has been underlooked even though it is not uncommon and can be easily diagnosed and treated. In conclusion, the result of our study suggests that abnormal sensory symptoms on hands and feet, especially 'cold hands and feet syndrome', the conventional circulatory disorder, are the medical condition where special concern on Raynaud's disease is required.
Adult ; Asia ; Carpal Tunnel Syndrome ; Connective Tissue ; Depression ; Diagnosis* ; Drinking ; Female ; Fingers ; Foot* ; Hand* ; Humans ; Hypertension ; Hypothyroidism ; Joints ; Myocardial Ischemia ; Nervous System Diseases ; Prevalence ; Raynaud Disease* ; Sensation* ; Smoke ; Smoking ; Thyroid Diseases ; Surveys and Questionnaires