• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.1
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• pp.96-109
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• 1996

The airbag system is known to be extremely efficient for the protection in an automobile crash. The performance of the airbag system is evaluated by real tests. However, the test is very difficult and expensive. Therefore, the computational simulations are carried out with low cost. The airbag analysis is included in the anlysis of the full-car crashworthiness. The behavior of the airbag can be predicted by a thermodynamic analysis. The contact force between the occupant and the airbag is calculated from the contact volume and the pressure in the airbag. The injury rate is evaluated from the contact force and the acceleration of dummies. So far, the contact is defined after the airgag is fully inflated. In many cases, the occupant is seated in the out-of-position and the contact can happen during the inflation process. A new algorithm has been developed for the out-of-position. To describe the inflation process precisely, the airbag is defined by a sphere and a torus. The injury is evaluated for the contact happened at any time. The developed algorithm is coded and interfaced with an existing software in the public domain. The full-car modeling is adopted from the previous study which is tuned for the regular position and real tests. Numerical experimentation have been carried out with a couple of dummies in the out-of-position and the injury processes are analyzed.

• Archives of Pharmacal Research
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• v.22 no.5
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• pp.479-484
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• 1999

In this study, the effects of ursodeoxycholic acid (UDCA) on ischemia/reperfusion injury were investigated on isolated heart perfusion model. Hearts were perfused with oxygenated Krebs-Henseleit solution (pH 7.4, $37^{\circ}C$) on a Langendroff apparatus. After equilibration, isolated hearts were treated with UDCA 20 to 160 $\mu$M or vehicle (0.04% DMSO) for 10 min before the onset of ischemia. After global ischemia (30 min), ischemic hearts were reperfused and allowed to recover for 30 min. The physiological (i.e. heart rate, left ventricular developed pressure, coronary flow, double product and time to contracture formation) and biochemical (lactate dehydrogenase; LDH) parameters were evaluated. In vehicle-treated group, time to contracture formation was 21.4 min during ischemia, LVDP was 18.5 mmHg at the endpoint or reperfusion and LDH activity in total reperfusion effluent was 54.0 U/L. Cardioprotective effects of UDCA against ischemia/reperfusion consisted of a reduced TTC $(EC_{25}=97.3{\mu}M)$, reduced LDH release and enhanced recovery of cardiac contractile function during reperfusion. Especially, the treatments of UDCA 80 and $160 {\mu}M $ significantly increased LVDP and reduced LDH release. Our findings suggest that UDCA ameliorates ischemia/reperfusion-induced myocardial damage.

• Journal of Korean Neurosurgical Society
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• v.38 no.3
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• pp.211-214
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• 2005

Objective : Post-traumatic hydrocephalus is a complication of head injury and can present with several different clinical symptoms. However, the developing factors of post-traumatic hydrocephalus and treatment are still not well known. The authors design the study to focus on incidence, causing diseases and treatment of post-traumatic hydrocephalus. Methods : The 789patients of traumatic head injury followed by admission treatment over 7days from Jan. 1997 to Dec. 2001, were divided shunt group and shunt free group. We analyzed age, sex, causing diseases, developing time of hydrocephalus and effects of shunt operation in post-traumatic hydrocephalus. Results : The incidence of post-traumatic hydrocephalus for requiring shunt was 9.2% [64cases]. Chronic hydrocephalus which developed after 14days of injury was higher incidence [51cases]. We found following variables were significantly related to shunt-dependent hydrocephalus : low GCS score at admission, initial CT finding of traumatic subarachnoid hemorrhage and intracerebral hemorrhage [including intraventricular hemorrhage]. The effect of shunt operation was not related with the spinal pressure, but had statistically significant correlation with the response of lumbar drainage. Conclusion : We conclude that development of hydrocephalus after head trauma is related to low GCS score, intracerebral hemorrhage [including intraventricular hemorrhage] and subarachnoid hemorrhage. The effect of preoperative lumbar drainage has a significant role in predicting the result of shunt operation in patient with post-traumatic hydrocephalus.

• The Korean Journal of Emergency Medical Services
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• v.24 no.3
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• pp.147-154
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• 2020

Purpose: The purpose of the study was to investigate traumatic urethral injury in a 63-year-old patient with hematuria. Methods: A hematuria patient was transferred by paramedics. At the time of the visit, the patient's blood pressure (151/91mmHg), pulse rate (86/min), body temperature (37.1℃), and other vital signs were stable. Their KTAS (Korean Triage and Acuity Scale) was Level 4. The patient had no damage to the injured area, but a large contrast defect was observed between the prostate urethra and the bladder in urethral angiography performed due to persistent hematuria and pain in the injured area. Results: Following radiological evaluation of a suspected liposarcoma or neuroma mass of the prostate urethra, the mass was removed through urethral tumor resection. The result of histologic evaluation provided a diagnosis of highly differentiated invasive urethral cell carcinoma that had invaded the muscle layer. The patient was given additional treatment for urethral cancer but was rejected and is currently being followed. Conclusion: The prognosis for urinary tract cancer has distinct differences for patients with lymph node metastasis and tumor characteristics. The presence or absence of urethral cancer should be confirmed through angiography, CT, MRI, and cystoscopy.

• Safety and Health at Work
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• v.9 no.4
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• pp.434-440
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• 2018

Background: In industrial countries, home care of community dwelling elderly people is rapidly growing. Frequent injuries in home caregivers result from slips, trips, and falls (STFs). The current study tests attentional cognitive failure to mediate the association between work stressors and STFs. Methods: A sample of 125 home caregivers participated in a questionnaire study and reported work interruptions, unreasonable tasks, quality-threatening time pressure, conscientiousness, attentional cognitive failures, and STFs. Results: In structural equation modeling, the mediation model was shown to fit empirical data. Indirect paths with attentional cognitive failures as the link between work stressors and STF were all significant in bootstrapping tests. An alternative accident-prone person model, that suggests individual differences in conscientiousness to predict attentional cognitive failures that predict more frequent work stressors and STFs, showed no significant paths between work conditions and STFs. Conclusion: To prevent occupational injury, work should be redesigned to reduce work interruptions, unreasonable tasks, and quality-threatening time pressure in home care.

• Journal of Korean Biological Nursing Science
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• v.16 no.4
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• pp.342-348
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• 2014

Purpose: The purpose of this study was to examine the effects of pressure ulcer classification system education on hospital nurses' knowledge and visual discrimination ability of pressure ulcer classification system and incontinence-associated dermatitis. Methods: One group pre- and post-test was used. A convenience sample of 96 nurses participating in pressure ulcer classification system education, were enrolled in single institute. The education program was composed of a 50-minute lecture on pressure ulcer classification system and case-studies. The pressure ulcer classification system and incontinence-associated dermatitis knowledge test and visual discrimination tool, consisting of 21 photographs including clinical information were used. Paired t-test was performed using SPSS/WIN 18.0. Results: The overall mean difference of pressure ulcer classification system knowledge (t=4.67, p<.001) and visual discrimination ability (t=10.58, p<.001) were statistically and significantly increased after pressure ulcer classification system education. Conclusion: Overall understanding of pressure ulcer classification system and incontinence-associated dermatitis after pressure ulcer classification system education was increased, but tended to have lack of visual discrimination ability regarding stage III, suspected deep tissue injury. Differentiated continuing education based on clinical practice is needed to improve knowledge and visual discrimination ability for pressure ulcer classification system, and comparison experiment research is required to evaluate its effects.

• Archives of Plastic Surgery
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• v.49 no.2
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• pp.275-284
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• 2022

Background Population aging has led to an increased incidence of pressure ulcers, resulting in a social burden and economic costs. We developed a three-dimensional knitted fabric (3-DKF) with a pressure-reducing function that can be applied topically in the early stages of pressure ulcers to prevent progression. Methods We evaluated the effects of the 3-DKF in a streptozotocin-induced diabetes mellitus pressure ulcer mouse model, and the fabric was preliminarily applied to patients. Twelve-week-old male C57BL/6 mice were used for the animal experiments. In the pressure ulcer mouse model, an ischemia-reperfusion injury was created using a magnet on the dorsa of the mice. Pressure was measured with BodiTrak before and after applying the 3-DKF to 14 patients at risk of sacral pressure ulcers. Results In the 3-DKF-applied mice group, the ulcers were shallower and smaller than those in the control group. Compared with the mice in the control group, the 3-DKF group had lower platelet-derived growth factor-α and neutrophil elastase expression, as parameters related to inflammation, and increased levels of transforming growth factor (TGF)-β1, TGF-β3, proliferating cell nuclear antigen, and α-smooth muscle actin, which are related to growth factors and proliferation. Additionally, typical normal tissue staining patterns were observed in the 3-DKF group. In the preliminary clinical analysis, the average skin pressure was 26.2 mm Hg before applying the 3-DKF, but it decreased to an average of 23.4 mm Hg after 3-DKF application. Conclusion This study demonstrated that the newly developed 3-DKF was effective in preventing pressure ulcers through testing in a pressure ulcer animal model and preliminary clinical application.

• Journal of Trauma and Injury
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• v.26 no.2
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• pp.39-46
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• 2013

Purpose: Non-invasive blood pressure measurement is widely used as a pre-hospital triage tool for blunt trauma patients. However, scant data exits for using the mean arterial pressure (MAP), compared to the systolic blood pressure, as a guiding index. The aim of this study was to determine the association between adverse outcomes and mean arterial pressure (MAP) and to exhibit the therapeutic range of the MAP in adult blunt trauma patients. Methods: The electronic medical records for all trauma patients in a single hospital from January 2010 to September 2012 were retrospectively reviewed. Patients below 17 years of age, patients with penetrating injuries, and patients with serious head trauma (injuries containing any skull fractures or any intracranial hemorrhages) were excluded. Adverse outcomes were defined as one of the following: death in the Emergency Department (ED), admission via operating theater, admission to the intensive care unit, transfer to another hospital for emergency surgery, or discharge as hopeless. Results: There were 14,537 patients who met entry criteria. Adverse outcomes occurred for MAPs in range from 90 to 120 mmHg. Adverse outcomes were found, after adjusting for confounding variables, to occur increasingly as the MAP declined below 90 mmHg or rose above 120 mmHg. Conclusion: Not only lower but also higher mean arterial pressure is associated with increased adverse outcomes in adult blunt trauma patients. Thus, patients with a MAP above 120 mmHg should be considered as a special group requiring higher medical attention, just as those with a MAP below 90 mmHg are.

• Journal of Trauma and Injury
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• v.33 no.1
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• pp.38-42
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• 2020

Purpose: Immediate post-laparotomy hypotension (PLH) is a precipitous drop in blood pressure caused by a sudden release of abdominal tamponade after laparotomy in cases of severe hemoperitoneum. The effect of laparotomy on blood pressure in patients with significant hemoperitoneum is unknown. Methods: In total, 163 patients underwent laparotomy for trauma from January 1, 2013 to December 31, 2015. Exclusion criteria included the following: negative laparotomy, only a hollow viscous injury, and hemoperitoneum <1,000 mL. After applying those criteria, 62 patients were enrolled in this retrospective review. PLH was defined as a decrease in the mean arterial pressure (MAP) ≥10 mmHg within 10 minutes after laparotomy. Results: The mean estimated hemoperitoneum was 3,516 mL. The incidence of PLH was 23% (14 of 62 patients). The MAP did not show significant differences before and after laparotomy (5 minutes post-laparotomy, 67.5±16.5 vs. 68.3±18.8 mmHg; p=0.7; 10 minutes post-laparotomy, 67.5±16.5 vs. 70.4±18.8 mmHg; p=0.193). The overall in-hospital mortality was 24% (15 of 62 patients). Mortality was not significantly higher in the PLH group (two of 14 [14.3%] vs. 13 of 48 [27.1%]; p=0.33). No statistically significant between-group differences were observed in the intensive care unit and hospital stay. Conclusions: PLH may be less frequent and less devastating than it is often considered. Surgical hemostasis during laparotomy is important. Laparotomy with adequate resuscitation may explain the equivalent outcomes in the two groups.

• Journal of Korean Neurosurgical Society
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• v.55 no.1
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• pp.26-31
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• 2014

Objective : Early decompressive craniectomy (DC) has been used as the first stage treatment to prevent secondary injuries in cases of severe traumatic brain injury (TBI). Postoperative management is the major factor that influences outcome. The aim of this study is to investigate the effect of postoperative management, using intracranial pressure (ICP) monitoring and including consecutive DC on the other side, on the two-week mortality in severe TBI patients treated with early DC. Methods : Seventy-eight patients with severe TBI [Glasgow Coma Scale (GCS) score <9] underwent early DC were retrospectively investigated. Among 78 patients with early DC, 53 patients were managed by conventional medical treatments and the other, 25 patients were treated under the guidance of ICP monitoring, placed during early DC. In the ICP monitoring group, consecutive DC on the other side were performed on 11 patients due to a high ICP of greater than 30 mm Hg and failure to respond to any other medical treatments. Results : The two-week mortality rate was significantly different between two groups [50.9% (27 patients) and 24% (6 patients), respectively, p=0.025]. After adjusting for confounding factors, including sex, low GCS score, and pupillary abnormalities, ICP monitoring was associated with a 78% lower likelihood of 2-week mortality (p=0.021). Conclusion : ICP monitoring in conjunction with postoperative treatment, after early DC, is associated with a significantly reduced risk of death.