• Journal of Yeungnam Medical Science
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• v.6 no.2
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• pp.63-70
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• 1989

This paper describes to design and to examine the mechanical characteristics of high frequency jet ventilator. The device consists of Phase lock loop(PLL) system, solenoid valve driving control part and Air regulating system. This study is carried out by changing several factors such as endotracheal tube(E.T. tube)diameter, injector cannula diameter, 1%, and frequency(breaths/mim.) having direct effects on the gas exchange as well as parameters of the entrained gas by venturi effects, so as to measure the tidal volume and minute volume. This system characteristics were as follows : 1) Frequency : 6-594bpm 2) Inspiration time : 1-99% 3) Variance of input air pressure : 1-30PSI.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.4
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• pp.165-170
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• 2016

Long-term performance of the enthalpy exchange element is a topic of current interest due to the concern of possible performance degradation over time. In this study, a 350 CMH enthalpy recovery ventilator equipped with an enthalpy exchange element was installed in an office room, and the performance has been traced over the past 5 years. The appearance, overall dimension, thermal performance, leakage ratio and anti-bacterial performance were checked annually. Results showed that the change in thermal performance (sensible, latent and enthalpy efficiency) was negligible with periodic cleaning with an air gun. However, the leakage ratio increased with time, measuring 7.3% after 5 years. Anti-bacterial test revealed that no bacteria were found during the test period. The largest change in the dimension occurred at the middle location of the element, although the change was less than 2% of the initial value.

• Journal of Korean Biological Nursing Science
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• v.14 no.1
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• pp.57-65
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• 2012

Purpose: The purposes of this study were to identify the effect of music therapy on the physiologic index, anxiety and dyspnea of patients who are weaning from mechanical ventilators, and to compare the effects between western and Korean traditional music. Methods: The research format is repeated measures design. The subject group consisted of 21 patients being weaned from mechanical ventilators in a tertiary general hospital in Seoul. Each patient randomly received western music, rest, and Korean traditional music. Western and Korean traditional music were played on an MP3 head phone for 30 minutes. Patients get 30 minutes of rest between the 2 music styles and the rest period. Physiological indices, anxiety and dyspnea were measured before and after patients listened to both styles of music and the rest period. Anxiety and dyspnea were measured with a visual analogue scale. Results: Respiratory rates (RR), rapid shallow breath indexes (RSBI), anxiety and dyspnea decreased, and tidal volume (TV) increased after listening to Western and Korean tradition music in patients weaning from mechanical ventilators. Compared to western music, Korean traditional music yielded significant decreases in RR, RSBI, anxiety and dyspnea, and an increase of TV. Conclusion: Western and Korean traditional music would decrease RR, RSBI, anxiety and dyspnea and increase TV of patients who are weaning from mechanical ventilators. The effects are more pronounced in patients listening to Korean traditional music compared to western music.

• Clinical and Experimental Pediatrics
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• v.48 no.4
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• pp.401-405
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• 2005

Purpose : The use of mechanically-assisted ventilators at home reduces morbidity and improves the quality of life in children with chronic respiratory failure. But in Korea there is no clinical data of children with home mechanical ventilation. We investigated ventilator types, duration, the causes of failure or death, and the cost needed for care. Methods : We retrospectively analyzed the medical records of 21 children who were admitted and who applied for home mechanical ventilation at the Pediatric Intensive Care Unit in Asan Medical Center. Phone interviews took place after discharge. and interviewed by phone after discharge. Results : The median age was 31 months; the median duration with ventilator was 25 months. Underlying diseases were 16 neuromuscular diseases, one metabolic disease and four chronic respiratory diseases. The types of ventilator were pressure and volume type(16 and five patients, respectively). The frequency of ventilation failure was once per 19 months. Weaning could be performed in three cases. Frequencies of admission after receiving ventilators were 1.7 times per year; the most common cause was pneumonia. Nine patients(43%) died; four of them died because of endotracheal tube obstruction. The costs for medical care were about 1,110,000 won per month. Conclusion : There is an increment in the numbers of individuals who need mechanical ventilation support. The most common cause of death was endotracheal tube obstruction. The most important problem for the patients was medical cost. There needs to be more interest in patients with ventilator and social welfare systems to support their families need to be prepared.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.4
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• pp.175-184
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• 2017

With the improvement of living standards, the ventilation for the mitigation of indoor or outdoor air-pollution problems has recently attracted a lot of attention. Consequently, the ventilation for the supply of outdoor fresh air into a room is treated as an important building-design factor. The ventilation is generally divided into the forced and natural types; here, the former can control the ventilation rate by using mechanical devices, but it has the disadvantages of the equipment costs, maintenance costs, and noise generation, while the latter is applied to most workshops due to the absence of noise and the low installation and maintenance costs. In this experimental study, the ventilation performance of a typical rotating-type natural ventilator, which is called a "wind turbine," was investigated with the outdoor-wind velocity and the indoor/outdoor-temperature difference. From the experiment results, it was confirmed that the temperature difference of $10^{\circ}C$ corresponds to the ventilation driving force with an outdoor-wind velocity of 1.0 m/s. Additionally, the intake-opening area of a building also exerts a great effect on the ventilation rates.

• Fire Science and Engineering
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• v.30 no.6
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• pp.118-123
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• 2016

In the event of a building fire, it is important to control the smoke generated to ensure the safe evacuation of occupants. A natural smoke ventilator should be installed to exhaust the fire smoke in accordance with the Korean building Act and Code. On the other hand, the present law does not specify the contents regarding natural smoke ventilators sufficiently. The problems that occur in various parts, such as the installation target, installation location, free area, and the control and maintenance of natural smoke ventilators need to be solved. In this study, the problem of the current system was examined through domestic and foreign standards, preliminary research, and field investigations. In addition, suggestions for improvement are provided.

• Tuberculosis and Respiratory Diseases
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• v.83 no.2
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• pp.167-174
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• 2020

Background: The purpose of this study was to investigate the effect of early tracheostomy on clinical outcomes in patients requiring prolonged acute mechanical ventilation (≥96 hours). Methods: Data from 575 patients (69.4% male; median age, 68 years), hospitalized in the medical intensive care unit (ICU) of a university-affiliated tertiary care hospital March 2008-February 2017, were retrospectively evaluated. Early and late tracheostomy were designated as 2-10 days and >10 days after translaryngeal intubation, respectively. Results: The 90-day cumulative mortality rate was 47.5% (n=273) and 258 patients (44.9%) underwent tracheostomy. In comparison with the late group (n=115), the early group (n=125) had lower 90-day mortality (31.2% vs. 47.8%, p=0.012), shorter stays in hospital and ICU, shorter ventilator length of stay (median, 43 vs. 54; 24 vs. 33; 23 vs. 28 days; all p<0.001), and a higher rate of transfer to secondary care hospitals with post-intensive care settings (67.2% vs. 43.5% p<0.001). Also, the total medical costs of the early group were lower during hospital stays than those of the late group (26,609 vs. 36,973 USD, p<0.001). Conclusion: Early tracheostomy was associated with lower 90-day mortality, shorter ventilator length of stay and shorter lengths of stays in hospital and ICU, as well as lower hospital costs than late tracheostomy.

• Acute and Critical Care
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• v.33 no.4
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• pp.260-268
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• 2018

Background: The purpose of this study was to evaluate the clinical application of modified Burns Wean Assessment Program (m-BWAP) scoring at first spontaneous breathing trial (SBT) as a predictor of successful liberation from mechanical ventilation (MV) in patients with endotracheal intubation. Methods: Patients requiring MV for more than 72 hours and undergoing more than one SBT in a medical intensive care unit (ICU) were prospectively enrolled over a 3-year period. The m-BWAP score at first SBT was obtained by a critical care nursing practitioner. Results: A total of 103 subjects were included in this study. Their median age was 69 years (range, 22 to 87 years) and 72 subjects (69.9%) were male. The median duration from admission to first SBT was 5 days (range, 3 to 26 days), and the rate of final successful liberation from MV was 84.5% (n=87). In the total group of patients, the successful liberation from MV group at first SBT (n=65) had significantly higher m-BWAP scores than did the unsuccessful group (median, 60; range, 43 to 80 vs. median, 53; range, 33 to 70; P<0.001). Also, the area under the m-BWAP curve for predicting successful liberation of MV was 0.748 (95% confidence interval, 0.650 to 0.847), while the cutoff value based on Youden's index was 53 (sensitivity, 76%; specificity, 64%). Conclusions: The present data show that the m-BWAP score represents a good predictor of weaning success in patients with an endotracheal tube in place at first SBT.

• Journal of Korean Academy of Nursing
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• v.54 no.1
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• pp.32-43
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• 2024

Purpose: This study aimed to determine the impact of an intervention using voice recording of family members on pain, anxiety, and agitation in patients undergoing weaning from mechanical ventilation. Methods: A randomized control pre-post experimental design was implemented to 53 participants, with 27 and 26 participants in the experimental and control groups, respectively. A 70-second voice recording of a family member, repeated three times at 10-minute intervals was used as an intervention for the experimental group. Meanwhile, participants in the control group used headset for 30 minutes. Structured instruments were utilized to measure pain, anxiety, agitation, and the weaning process. Wilcoxon Signed Ranks test and the Mann-Whitney U test, or χ² test, were used for data analysis. Results: The experimental group exhibited significant decrease in pain (Z = - 3.53, p < .001), anxiety (t = 5.45, p < .001), and agitation (Z = - 2.99, p = .003) scores compared with those of the control group. However, there was no significant difference between groups in the weaning process' simplification (χ² = 0.63, p = .727). Conclusion: Intervention using family members' voice recording effectively reduces pain, anxiety, and agitation in patients undergoing weaning from mechanical ventilation. This can be actively utilized to provide a more comfortable process for patients.

• Korean Journal of Clinical Pharmacy
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• v.27 no.4
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• pp.207-213
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• 2017

Background: It is recommended to use aerosolized (AS) colistin in patients undergoing mechanical ventilation therapy as an adjunctive in the latest guidelines, in spite of high nephrotoxicity and limited studies. In this study, systematic reviews and meta-analyzes were conducted to evaluate the safety and efficacy of AS colistin in patients with ventilator-associated pneumonia Methods: Two authors independently searched related literature published from Pubmed and EMBASE until July 2016 and included a study comparing adjunctive AS colistin with intravenous (IV) colistin monotherapy. The primary outcome was the clinical response rate, the secondary outcome was the overall mortality, and nephrotoxicity. The publication bias was evaluated using the Egger's test. Results: Of the total 279 articles, nine were finally included in the final analysis. There was a significant difference between the adjunctive AS colistin group and the IV colistin monotherapy group for the treatment-response rate (odds ratio (OR), 1.56; 95% CI, 1.14-2.14; p = 0.005; $I^2=36%$), although there was no significant difference in overall mortality (OR, 0.77; 95% CI, 0.57-1.04; p = 0.09; $I^2=20%$). However, there was no significant difference between the two groups in nephrotoxicity (OR, 1.13; 95% CI, 0.74-1.74; p = 0.57; $I^2=4%$). Conclusion: The addition of aerosolized colistin to IV colistin monotherapy showed better results in terms of efficacy than IV colistin monotherapy and did not show any significant difference in terms of total mortality and nephrotoxicity. Additional large-scale studies of this need to be verified.