Acute respiratory symptoms and evacuation-related behavior after exposure to chlorine gas leakage

BACKGROUND: A study was performed on the accidental chlorine gas leakage that occurred in a factory of printed circuit boards manufactured without chlorine. Health examination was performed for all 52 workers suspected of exposure to chlorine gas, and their evacuation-related behaviors were observed in addition to analyzing the factors that affected the duration of their acute respiratory symptoms. METHODS: Behavioral characteristics during the incidence of the accidental chlorine gas leakage, the estimated time of exposure, and the duration of subjective acute respiratory symptoms were investigated. In addition, clinical examination, chest radiography, and dental erosion test were performed. As variables that affected the duration of respiratory symptoms, dose group, body weight, age, sex, smoking, work period, and wearing a protective gear were included and analyzed by using the Cox proportional hazard model. RESULTS: Of 47 workers exposed to chlorine gas, 36 (77 %) developed more than one subjective symptom. The duration of the subjective symptoms according to exposure level significantly differed, with a median of 1 day (range, 0–5 days) in the low-exposure group and 2 days (range, 0–25 days) in the high-exposure group. Among the variables that affected the duration of the acute respiratory symptoms, which were analyzed by using the Cox proportional hazard model, only exposure level was significant (hazard ratio 2.087, 95 % CI = 1.119, 3.890). Regarding the evacuation-related behaviors, 22 workers (47 %) voluntarily evacuated to a safety zone immediately after recognizing the accidental exposure, but 25 workers (43 %) delayed evacuation until the start of mandatory evacuation (min 5, max 25 min). CONCLUSIONS: The duration of the subjective acute respiratory symptoms significantly differed between the low- and high-exposure groups. Among the 27 workers in the high-exposure group, 17 misjudged the toxicity after being aware of the gas leakage, which is a relatively high number.

Overlap syndrome with Sjögren’s syndrome and systemic sclerosis in a steel rolling mill worker: a case report

BACKGROUND: There are few reports about work-related factors associated with Sjögren’s syndrome. We report a case of overlap syndrome with Sjögren’s syndrome and systemic sclerosis. CASE PRESENTATION: A 54-year-old man was admitted due to dyspnea on exertion. The results of physical examination and laboratory findings were compatible with Sjögren’s syndrome with systemic sclerosis. The patient had no pre-existing autoimmune disease, and denied family history of autoimmune disease. The patient worked in the large-scale rolling department of a steel manufacturing company for 25 years. Hot rolling is a rolling process performed at between 1100 °C and 1200 °C, generating a high temperature and a large amount of fumes, involving jet-spraying of water throughout the process to remove the instantaneously generated oxide film and prevent the high generation of fumes. In this process, workers could be exposed to silica produced by thermal oxidation. Other potential toxic substances including nickel and manganese seemed to be less likely associated with the patient’s clinical manifestations. CONCLUSIONS: Occupational exposure to silica seemed to be associated with the patient’s clinical manifestations of overlap syndrome with Sjögren’s syndrome and systemic sclerosis. Although the underlying mechanism is still unclear, autoimmune disease including Sjögren’s syndrome affects women more often than men and there was no family history of autoimmune disease. These suggested that there was an association between occupational silica exposure and the disease of the patient. Future research about the association between long-term low dose exposure to silica and the development of autoimmune diseases should be encouraged.

The association between shift work and hyperuricemia in steelmaking male workers

OBJECTIVES: The aim of this study was to examine the association between shift work and hyperuricemia among steel company workers. METHODS: We examined 1,029 male workers at a Korean steel company between June 6 and June 28, 2013. We conducted anthropometric measurements, questionnaire surveys, and blood tests. Hyperuricemia was defined as a serum uric acid concentration of > or =7.0 mg/dL. Logistic regression analyses were performed. In the full model, analysis was adjusted for covariates including age, body mass index, lifestyle factors, and comorbidities. The odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for all models. RESULTS: The participants included 276 daytime workers and 753 shift workers. Among daytime workers, 72 (26.1%) individuals had hyperuricemia, as did 282 (37.5%) individuals among shift workers (p <0.001). There was a statistically significant association between shift work and hyperuricemia. In the unadjusted model, the OR of shift work was 1.70 (95% CI 1.25-2.31) for hyperuricemia. In the full model, the OR of shift work was also statistically significant after adjustment for covariates (OR 1.41, 95% CI 1.02-1.96). CONCLUSIONS: Among male steel workers, a significant association between shift work and hyperuricemia was observed.

The Relevance of Hyperuricemia and Metabolic Syndrome and the Effect of Blood Lead Level on Uric Acid Concentration in Steelmaking Workers

OBJECTIVES: Uric acid concentration is known to increase the prevalence of metabolic syndrome by affecting its components, resulting in increased risk of cerebrovascular and cardiovascular diseases, and long-term lead exposure is known to affect this serum uric acid level. In this study, we aimed to examine the association between the causes of hyperuricemia and metabolic syndrome, and to determine whether an increased blood lead level affects hyperuricemia. METHOD: Anthropometric measurements, surveys, and blood tests were conducted between May and June 2012 in 759 men working in the steelmaking process at a domestic steel company. Workers were divided into 2 groups according to the presence or absence of hyperuricemia, and an analysis was performed to examine its association with metabolic syndrome. In addition, the workers were divided into 3 groups according to the blood lead level to analyze the association between blood lead and hyperuricemia. RESULTS: The geometric mean (standard deviation) of the blood lead levels in the hyperuricemia group was significantly higher than that of the healthy group (3.8 [1.8] vs. 3.3 [1.8] microg/dL). The adjusted odds ratio for metabolic syndrome of the hyperuricemia group increased significantly to 1.787 (1.125-2.839) compared with the healthy group. In addition, the adjusted odds ratios for the occurrence of hyperuricemia in the tertile 2 (2.61-4.50 microg/dL) and tertile 3 groups (>4.50 microg/dL) according to blood lead level significantly increased to 1.763 (1.116-2.784) and 1.982 (1.254-3.132), respectively, compared with the tertile 1 group (< 2.61 microg/dL). CONCLUSION: Hyperuricemia is believed to function as an independent risk factor for metabolic syndrome, while lead seems to increase the serum uric acid level even at a considerably low blood level. Therefore, attention should be given to patients with hyperuricemia and metabolic syndrome who are prone to lead exposure, and a prospective study should be conducted to identify their causal relationship.

Risk Assessment for Cardiovascular Diseases in Male Workers: Comparing KOSHA Guidelines and the Framingham Risk Score System / 대한산업의학회지

OBJECTIVES: This study aimed to investigate the 10-year risk of cardiovascular disease (CVD) by Framingham risk score (FRS) who classified as "healthy group" by Korean Occupational Safety and Health Agent (KOSHA)' s cardiovascular risk assessment. METHODS: The subjects of this study were 1,781 male workers in a large steel company. Health status was obtained periodically through medical examinations and questionnaires. We assessed cardiovascular risk using KOSHA guidelines and calculated the 10-year risk of cardiovascular disease using the Framingham risk score for those categorized to the "healthy group" by KOSHA guideline. A closer examination of cardiovascular risk factors was performed in 62 subjects paradoxically placed in the "healthy group" by KOSHA guidelines and the "high-risk group" by FRS. RESULTS: Among the "healthy group" by KOSHA's cardiovascular risk assessment, 230(15.8%) subjects had more than 3 CVD risk factors and 62(4.2%) subjects were high risk group (more than 20%) in 10-years risk of CVD by Framingham risk score. Modifiable risk factors included cigarette smoking (96.8%), high serum total cholesterol (82.3%), high serum triglyceride (66.1%), insufficient physical activity (66.1%), and obesity (58.1%). CONCLUSIONS: Among subjects with normal blood pressure, it seems that KOSHA guidelines underestimate CVD risk, identified by the Framingham risk score. For the effective prevention and management of CVD, modifiable risk factors, such as cigarette smoking, dyslipidemia, and obesity, need to be constructively controlled.

A Case of Silicosis and Pneumothorax in a Workplace Producing Dental Porcerlain / 대한산업의학회지

BACKGROUND: Silicosis is more likely to occur in people working in the mining industry. However, workers suffering from silicosis have recently been reported frequently in other areas. We present a case of silicosis occuring in a 43-year-old man who had worked for 20 years in a workplace producing dental porcelain. CASE: The man was admitted to the emergency room with acute chest pain caused by pneumothorax. Chest X-ray indicated numerous small opacities spread over the whole lung field and a large opacity in the right middle lung field. According to ILO classification, the shape of the small opacities was t/s, the profusion rate was 2/3 and the large opacity was classified into the B category. Following this diagnosis of silicosis, the patient's medical history and work exposure history were examined. According to his medical history, he had undergone closed thoracostomy in 2006 because he had suffered pneumothorax twice (in 2005 and 2006) and his smoking history was 7 pack years. In particular, he had been exposed to silica dust for 20 years in his workplace. CONCLUSION: Despite the absence of any specific risk factor that caused pneumothorax, the patient suffered this condition three times. All clinical results and the progress of his physical symptoms, including radiologic findings from chest X-ray and computed tomography, clearly supported the diagnosis of silicosis. Except for exposure to silica dust in the workplace, no other risk factors causing silicosis were found. Therefore, he was finally diagnosed as having silicosis caused by exposure to silica dust in the workplace and followed by pneumothorax.

Area-Based Occupational Disease Surveillance in Incheon, Korea: Results of an 11-year Data Survey / 대한산업의학회지

OBJECTIVES: Between Jan 1998 and Dec 2008, area-based occupational disease surveillance in Incheon was used to collect data on occupational diseases. The long-term data was used to estimate the scale of disease, to analyze disease characteristics, and to achieve surveillance in order to determine development tasks. METHODS: For a period of 11 years, occupation-related disease surveillance was performed on an annual basis for employees of Incheon industries. All cases of occupational disease were reported by means of the Incheon Occupational Disease Information Network (IODIN) web site, downloaded, and analyzed, subsequently. RESULTS: Between Jan 1998 and Dec 2008, 1577 cases of occupational disease were reported. Of these, there were 1043(66.1%) cases of occupational musculoskeletal disorders, 172(10.9%) cases of occupational asthma, 162(10.3%) cases of occupational dermatoses, 135(8.6%) cases of occupationally-related cancers, 30(1.9%) cases of pneumoconiosis, 27(1.7%) cases of toxic hepatitis, and 8(0.5%) cases of occupational neuronal disease. CONCLUSION: In the Incheon area, small and medium industries comprise 99% of business. The composition of the industry by category, in Incheon, is similar to the country on the whole. In actually, the data on occupational diseases in Korea are almost workers' compensation data. Thus, the survey of occupational disease based in Incheon, Korea, can serve as an estimate of the trends and size of the occupational disease throughout the entire country.

Validity of NIOSH- and Nordic-style Questionnaires in the Screening and Surveillance of Neck and Upper Extremity Work-related Musculoskeletal Disorders / 대한산업의학회지

OBJECTIVES: The study aimed to compare the validity of two questionnaires (NIOSH- and Nordic-style) which are used for the screening and surveillance of neck and upper extremity work-related musculoskeletal disorders. To evaluate the validity, clinical examination was used as the reference. METHODS: Two types of questionnaire were filled out by 208 workers from three different plants in Incheon, Korea. Workers underwent clinical examination by three occupational physicians. The presence of a symptom or sign in at least one body region was regarded as positive in both results of questionnaire and case definition using clinical examination. Validity was evaluated by sensitivity, specificity, positive predictive value, negative predictive value and agreement (Kappa coefficient). For the Nordic-style questionnaire, the sum of the symptom scores was used to yield the ROC curve. RESULTS: The results of the NIOSH-style questionnaire were sensitivity 59.5%, specificity 68.0%, positive predictive value 68.0%, negative predictive value 59.5%, and Kappa coefficient 0.27(95% confidence interval [CI]=0.14~0.40). The results of the Nordic-style questionnaire were sensitivity 73.9%, specificity 68.0%, positive predictive value 72.6%, negative predictive value 69.5%, and Kappa coefficient 0.42 (95% CI=0.30~0.54). For the Nordic-style questionnaire, sensitivity was 72.1% and specificity was 70.1% based on the sum of the symptom scores > or =2. CONCLUSIONS: Both questionnaires demonstrated appropriate validity for the screening and surveillance of work-related musculoskeletal disorders. The selection of questionnaire may depend on the purpose of investigation and characteristics of the work place.

Result of Sugioka's Transtrochanteric Osteotomy forOsteonecrosis of Femoral Head / 대한정형외과학회잡지

PURPOSE: The results of Sugioka's transtrochanteric rotational osteotomy are controversial. While many Japanese studies have reported favorable results, European and American studies have been disappointing. We present the results of Sugioka's rotational osteotomy for extensive osteonecrosis of the femoral head in young patients. METHODS AND MATERIALS: Between April. 1994 and May. 2004, Sugioka's osteotomy was performed for osteonecrosis involving a large part of the weight bearing area on 49 hips (46 patients). Of these 49 hips, 45 (43 patients) were available for follow-up. The patients were followed up for at least 2 years with an average of 52 months (range: 24-132 months). The major causes of osteonecrosis were chronic alcohol abuse in 33 hips. The mean age of the patients at the time of surgery was 31 years (range: 21-46), and the male to female ratio was 39:6. Six, 17 and 22 hips were classified as stage IIA, IIb and III using the Ficat and Alert classification, respectively. RESULTS: Thirty three of the 45 hips (74%) survived clinically and radiologically. Of these, the clinical results were excellent, good and fair in 15, 12 and 6 hips, respectively. Major complications were encountered in 12 hips [Progressive severe varus deformity in 7 hips (15%)], femur neck fracture in 3 hips (6%) and deep infection in 2 hips (4%). Among these 12 hips, seven hips (15%) required secondary THA. Five other hips (11%) were also subsequently converted to THA due to progressive collapse of the femoral head after the transtrochanteric osteotomy. CONCLUSION: Transtrochanteric osteotomy can be used to treat osteonecrosis of the femoral head in young patients with extensive necrotic lesions of the femoral head. However, Sugioka osteotomy should be used with caution due to its high incidence of complications.

Metallic Radial Head Prosthesis in Korea

Purpose: The aim of this study was to report seven cases of metallic radial head prosthesis and present the limit of use in Korea. Materials and Methods: Metallic radial head arthroplasty was performed on 7 patients between April 2006 and December 2006, who had complex elbow injury including comminuted radial head fracture. Indication, operative findings and outcome were assessed. Availability and payment of implant were investigated. Results: All of the patients had more than one associated injury including coronoid fracture, olecranoan fracture, and ligament ruptures. According to Mason classification, there were three type III and four type IV fractures. All radial head fractures were too comminuted to reconstruct. There were two excellent results, four good, and one poor, as graded by Mayo score. There were no patient with instability and implant related complications. Insufficient supply of implant did not enable to do scheduled surgery in 2 cases. Current medical insurance did not cover charge for radial prosthesis, five patients could not help paying for that by themselves. Conclusion: Metallic radial head implants are useful when the radial head cannot be repaired reliably. Preoperative preparing and coverage by medical insurance based on appropriate indication are helpful for decision for a treatment option.

Comparison of LC-DCP versus LCP for Internal Fixation of Humeral Shaft Fractures in Elderly Patient

PURPOSE: To compare outcomes of humeral shaft fractures fixed with locking compression plate and those fixed with dynamic compression plate in elderly patients. MATERIALS AND METHODS: Nineteen consecutive elderly patients with a fracture of the humeral diaphysis were evaluated retrospectively. Ten patients had been fixed with LC-DCP, and nine had been fixed with LCP. Radiological and clinical results were compared and comparison of implants was done. RESULTS: Loosening of the plate occurred in one case each from the LCP group and the LC-DCP group. The rest of the patients achieved union uneventfully without any complications. Union rate, clinical score and hardware were not significantly different between the two groups. One patient who developed loosening in the LC DCP underwent reoperation whereas one patient with loosening in the LCP was successfully managed conservatively. CONCLUSION: Principle of fracture fixation was more important than plate selection in humeral shaft fracture of elderly patient.

Importance of job demands, career development, role pressure, and economic-issue-related job stress as risk factors for work related musculoskeletal disorders in electronics assembly line workers / 대한산업의학회지

OBJECTIVES: To evaluate the association of upper extremity musculoskeletal disorders with job demand-control and effort-reward related job stress. METHODS: Questionnaires concerning symptoms, psychosocial factors and work conditions were completed by 436 workers from a refrigerator assembly line, mobile phone assembly line, and an office, musculoskeletal conditions of the upper extremities were defined by the frequency, duration, and intensity of symptoms. A walk-through survey was performed to evaluate various physical work factors. Data were analyzed with the use of logistic regression. RESULTS: A total of 382 workers completed the survey, for whom neck and shoulder symptoms were the most frequently reported, followed by finger and wrist, and then elbow symptoms. Both awkward working posture and forceful exertion were associated with an increase in shoulder/neck and finger/wrist symptoms. In addition, job stress factors such as monotony, low job clarity, low job control, low promotion prospect, economic issues, and retirement pressures were associated with increased neck/shoulder, elbow, and finger/wrist conditions. Women were more likely to report symptoms, and the association between musculoskeletal conditions and job stress factors was stronger in female assembly line workers and office workers than in male assembly line workers. CONCLUSIONS: The results suggest that musculoskeletal conditions of the upper extremities are associated with not only physical work factors but also job stress factors. In particular, economic issues and career development factors are important influences on workers in Korea.

Comparison of Bone Tunnel Widening after ACL Reconstruction between Bioabsorbable Interference Screw and Metallic Interference Screw Fixation

PURPOSE: We evaluated the relationship among the radiographic enlargement of femoral and tibial bone tunnels, fixation material, clinical results and period of follow-up after anterior cruciate ligament(ACL) reconstruction with single incision arthroscopic technique using bone-patella tendon-bone. MATERIALS AND METHODS: We evaluated 91 knees of arthroscopic ACL reconstruction during the period of June 1993 to February 2001 excluding combined posterior cruciate ligament(PCL) injury. Average follow-up period was 44 months(12-78 months). We classified these cases into bioabsorbable screw group and metal screw group according to the screw materials. We took anteroposterior and lateral X-ray films at postoperative 3 months, 1 year, final follow up and measured the size of femoral and tibial tunnel. We evaluated the side-to-side difference using KT-2000 arthrometer and clinical results with Lysholm score. RESULTS: Eight cases of 47 cases in bioabsorbable screw group had bony cystic changes at femoral tunnel and 44 cases in metal screw group had not. Tibial tunnel widening was seen in 38 cases of absorbable screw group and 31 cases of metal screw group. Cases which had femoral and tibial tunnel widening had no knee joint instability clinically. CONCLUSION: There were femoral tunnel widening in bioabsorbable screw group, but not in metal screw group. Delayed inflammatory reaction in bioabsorbable screw may make this phenomenon but there was no correlation between femoral tunnel widening and clinical results. More longterm follow-up will be needed for futher degenerative changes and graft failure.

Popliteal Artery Entrapment Syndrome: A Case Report / 대한정형외과학회잡지

Popliteal artery entrapment syndrome is a rare but potentially limb threatening anatomical anomaly occurring predominantly in young adults. We experienced a case of a 19 year old man who had suffered from a coldness of his left lower leg, without past history of trauma. Angiogram and MRI were performed and we diagnosed as a popliteal artery entrapment syndrome. The popliteal artery was entrapped in its abnormal course around the medial head of the gastrocnemius muscle, which originated from the femur laterally and the cephalad. Thrombectomy, decompression of the popliteal artery and reposition of the medial head of the gastronemius muscle were successfully done. Blood flow was restored after surgical repair.

The association between unexplained elevation of second trimester maternal serum beta-hCG and pregnancy outcomes / 대한산부인과학회잡지

OBJECTIVE: The purpose of this study was to determine whether unexplained elevation of second-trimester maternal serum beta-human chorionic gonadotropin (beta-hCG) is associated with adverse pregnancy outcomes. METHOD: Between January 1998 and December 1999, we evaluated 2112 pregnant women undergoing second trimester triple marker screening test who delivered at our hospital. Inclusion criteria were singleton pregnancy, confirmed gestational age, and hCG level greater than 2.0 MoM. The exclusion criteria were fetal anomaly, abnormal karyotype, MSAFP level greater than 2.0 MoM, uE3 level less than 0.4 MoM, and referred patients with pregnancy-induced hypertension (PIH). A group of randomly selected women with normal maternal serum hCG and AFP levels served as control. RESULTS: Women with unexplained elevation of hCG level showed increased risks for PIH (p<0.001) and preterm delivery (p<0.003). There were no significant diffrences between study and control groups with respect to placental abruption, fetal distress, PROM, intrauterine fetal death, and apgar score. CONCLUSION: Pregnancies with unexplained elevation of hCG levels should be regarded as high-risk pregnancies and managed accordingly. The combination with these biomarkers such as VEGF, plasminogen activating factor I and AT-III as a screening test for PIH may be useful.

Local occupational disease surveillance system in Korea: Current status and issues / 대한산업의학회지

No abstract available.

Local occupational disease surveillance system in Korea: Current status and issues / 대한산업의학회지

No abstract available.

The Implementation of the Moral Education Program in a Medical School Using Dilemma Discussion / 한국의학교육

Gachon Medical School has developed and implemented a medical ethics course entitled, "Life and Society II". The course uses dilemma discussion based on medical case studies to allow students to develop their moral reasoning ability in both clinical and hospital settings. The course was developed by the faculty of medicine during the 1998-1999 academic years. The program was designed in a four-stage process: 1) learning objectives were identified, 2) contemporary controversies and relevant ethical issues were chosen based on relevance to modern medical practice, 3) a syllabus was drafted based on the aforementioned ethical issues and teaching methods appropriate for each issue were integrated into the syllabus, and 4) tutorial manuals were produced. The course was taught to 41 second-year premedical students and evaluated by student surveys. The learning goals were identified through both a literature survey of contemporary issues in medical ethics and an in-house survey of important content to teach in a medical ethics course. The curriculum was designed based on the identification of specific learning objectives per ethical issue, selection of appropriate materials and content, organization of dilemma scenarios and formulation of questions for discussion. The course was taught using a variety of teaching formats: dilemma discussions, seminars, tutorials, lectures, assigned readings and student presentations. Positive results were obtained from the student surveys: it was discovered that most students thought that the course's learning objectives were achieved. Furthermore, of all the teaching methods employed, most of our students felt that discussing dilemmas was the most effective method for developing moral reasoning ability.

The Prevalence and Characteristics of Cumulative Traumatic Disorders

OBJECTIVE: To investigate the current status and the basic information of cumulative traumatic disorder among workers. METHOD: The subjects were 198 workers, consisted of 100 shipspublisher workers, 155 telephone operators and 43 light workers. Workers were surveyed with a standardized self- administered questionnaire and examed by the occupational medicine doctors and physiatrists for the cumulative traumatic disorders. Laboratory tests, nerve conduction studies and X-rays of the C-spine and shoulders were performed in all subjects. RESULT AND CONCLUSION: Myofascial pain syndrome was the most frequent problem in the shipspublisher and telephone operators. As a result of the multiple logistic regression analysis, cycle time, palm pinch, lumbar and neck flexion were the significant variables accounting for the musculoskeletal symptoms.

Medical Counseling by Interact via Daily Newspaper / 대한의료정보학회지

Recently the change in medical informatics enabled us to use medical information whenever we want and wherever we are. There are many homepages on the web, which provide hospital information, medical counseling. Our multimedia center began its service as a internet Hospital in MIDAS Dongailbo, one of the major daily newspaper in Korea, on March 25th, 1997. The aim of this study is to examine the content and purpose of medical counseling on the web. The subjects consisted of 1,000 counsellings which were called 'Dongailbo Internet Hospital' for March, 25th, 1997 through October 30th, 1997. Many questioners wanted to know treatment principles, to make a diagnosis, and to know specific medical knowledges. The most common questions are as follows: general and unspecified, musculoskeletal, skin, digestive, respiratory, neurological problems.