Does the dominant hand’s use affect the complication rates in prosthetic breast reconstruction?

정성흠,황은아,하현정,김태현,김덕열,Chung Hun Kim,김석화,안희창 대한미용성형외과학회 2023 Archives of Aesthetic Plastic Surgery Vol.29 No.4

Background Numerous studies have investigated risk factors for unfavorable outcomes in prosthetic breast reconstruction, such as obesity, perioperative radiotherapy, and acellular dermal matrix use. However, no reports have explored whether the use of the dominant hand influences complications in breast reconstruction. To address this gap in the literature, analyzed complication rates between the dominant and non-dominant sides after reconstruction. Methods We retrospectively reviewed the charts of 160 patients (170 breasts) who underwent breast reconstruction from February 2017 to March 2022. We analyzed the complications between beasts on the dominant and non-dominant sides according to the reconstruction method. Results During prosthetic breast reconstruction, the drainage volume and duration on the dominant side exceeded those on the non-dominant side after reconstruction (duration: 9.79 days on the dominant side vs. 9.12 days on the non-dominant side, P=0.196; volume: 771.1 mL on the dominant side vs. 654.3 mL on the non-dominant side, P=0.027). The incidence of complications such as wound dehiscence, mastectomy flap necrosis, and infection was significantly higher in the dominant hand group (infection: 6 vs. 0, P=0.014; dehiscence: 15 vs. 4, P=0.009; flap necrosis: 13 vs. 4, P=0.024). Conclusions Complications including seroma, infection, and mastectomy skin flap necrosis following prosthetic reconstruction were common in breasts on the dominanthand side. Therefore, meticulous management and restriction of shoulder movement can aid in preventing seroma-related complications in prosthetic breast reconstruction, especially on the side of the dominant hand.

커먼레일 디젤엔진에서 바이오디젤 연료의 혼합비율에 대한 배기가스의 특성 평가

백석흠(Seok Heum Baek),윤정환(Jeong Hwan Yoon),정우성(Woo Sung Jung),하형수(Hyeong Soo Ha),정성식(Sung Sik Chung),염정국(Jeong Kuk Yeom) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.5

In this study, the characteristics of exhaust gas according to mixing ratio of bio diesel fuel were evaluated. The fuels which was used in this study are biodiesel mixed fuel of 3%, 5%, 20%, 50% and 100% Also, injection pressures as a experimental variable were set to 400bar, 600bar, 800bar, 1000bar and 1200bar. Generally, unlike Soot emissions, the more injection pressure is applied, the more nitrogen oxides(NOx) are occurred. To analyze experiment data about NOx and Soot, Pearson correlation coefficient and Spearman rank-order correlation coefficient were used. Consequently, the values of Pearson correlation and Spearman rank-order correlation coefficient were ?0.732 and ?0.724. There is little difference between the two values. Since the two values is less than l, the relation of NOx and Soot in linear. At 800bar, Pearson correlation coefficient is ?0.89. Therefore, in order to remove NOx and Soot, this paper reveal that 800bar condition is advantageous.

디젤엔진에서 바이오디젤의 배기가스 특성 평가

백석흠(Seok Heum Baek),윤정환(Jeong Hwan Yoon),정우성(Woo Sung Jung),하형수(Hyeong Soo Ha),정성식(Sung Sik Chung),염정국(Jeong Kuk Yeom) 대한기계학회 2014 大韓機械學會論文集B Vol.38 No.2

본 연구에서는 바이오디젤연료 혼합비변화에 대한 디젤엔진의 배기특성에 대해 조사하였다. 실험에 사용된 연료는 경유와 바이오디젤(폐식용유) 혼합연료 BD3, BD5, BD20, BD50 및 BD100을 사용하였으며, 실험변수로서 분사압력(ΔPinj)을 400bar, 600bar, 800bar, 1000bar 및 1200bar로 설정하였다. 분사압력과 바이오디젤 혼합연료 혼합비에 따른 정량적인 NOx와 Soot의 배기특성 해석을 위하여 통계학에 기초한 피어슨 상관계수와 스피어만 상관계수의 개념을 도입하였다. 본 연구의 결과로서 실험 조건 전체에 대한 피어슨 상관계수는 -0.732, 스피어만 상관계수는 -0.724로 NOx와 Soot 발생의 상관관계가 선형적이다. 특히 분사압력 800bar 조건에서 피어슨 상관계수가 -0.089으로 NOx와 Soot 배출량 상관관계가 0에 가깝기 때문에, 바이오디젤 연료 혼합비 제어를 통한 NOx와 Soot의 동시저감이 가능하다고 판단된다. In this study, the characteristics of exhaust gas as a function of the biodiesel mixing ratio were investigated. Diesel and waste oil were used for preparing mixed fuel, and the ratios of the mixed fuel were varied in the BD3~BD100 range. The injection pressures(ΔPinj) was considered as an experimental variable and was set to 400 bar, 600 bar, 800 bar, 1000 bar, and 1200 bar. Furthermore, for quantitatively analyzing the characteristics of exhaust gas(NOx and Soot), the concepts of Pearson correlation coefficient and Spearman rank-order correlation coefficient based on statistics were introduced. Consequently, it was found that the correlation of the emission of NOx and Soot is linear, and the Pearson and Spearman coefficients are -0.732 and -0.724, respectively, under all analysis conditions. Especially, for the injection pressure of 800 bar, a simultaneous reduction in NOx and Soot emission is possible by controlling the biodiesel mixing ratio. This is because the correlation coefficients of NOx and Soot emissions were nearly 0, as the Pearson correlation coefficient was -0.089.

Effectiveness of a postoperative continuous irrigation system via a catheter following implant-based breast reconstruction

하현정,정성흠,김태현,안희창,황은아 대한미용성형외과학회 2023 Archives of Aesthetic Plastic Surgery Vol.29 No.1

Background Implant-based breast reconstruction is a technique frequently used for breast reconstruction. Infection and inflammation are considered to be the most troublesome complications of implant-based breast reconstruction and can lead to capsular contracture or implant failure. To date, however, only a few methods have been proposed to prevent these complications. Therefore, the authors introduce a simple irrigation system using indwelling drain catheters to decrease postoperative inflammation. Methods Continuous saline irrigation was performed once per day for 3 days immediately after prosthesis-based breast reconstruction. Normal saline (500 mL) was inserted into the implant pocket through a superomedial-oriented drain catheter and drained through an inferolateral-oriented drain catheter using a suction device. Inflammatory indicators, including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cell count (WBC), and postoperative complications were compared between the non-irrigation and irrigation groups. Results This study included 37 patients divided into two groups (20 non-irrigation and 17 irrigation). An analysis of inflammatory indicators revealed that the peak CRP level in the irrigation group was significantly lower than that in the non-irrigation group, while no statistically significant differences were found for the other mediators (ESR and WBC). In the immediate postoperative period, continuous irrigation effectively washed out tissue debris and blood clots within the implant pocket, which helped maintain the function of the drain catheter and decrease pro-inflammatory mediators. Conclusions This irrigation method was simple and cost-effective for decreasing inflammation within the breast pocket. Furthermore, it can also be applied to infected breast pockets in combination with antibiotics.

지역사회 노인을 위한 대면과 비대면 운동프로그램이 운동 만족도에 미치는 영향

이다솔,이한숙,김래현,김예슬,김채윤,박범식,박병현,신미지,오은주,우수민,유지민,이주연,정성흠,정효규 대한물리의학회 2023 대한물리의학회지 Vol.18 No.1

PURPOSE: The study compared the satisfaction of the exercise program in a face-to-face and non-face-to-face manner with the same exercise program. METHODS: This study was conducted through convenience sampling for 57 seniors over 65 years of age. After conducting 30 minutes of the same exercise program face-to-face on the first visit and non-face-to-face on the second visit, a satisfaction survey was conducted. The survey data were processed statistically using SPSS 26.0 (SPSS Inc, IBM, USA). An independent t-test was used to compare the type of exercise program. The Spearman's Rank Correlation was conducted to correlate the satisfaction between cognitive function and education level. RESULTS: The overall satisfaction with the face-to-face program was higher than the non-face-to-face exercise programs. All three satisfaction items in face-to-face exercise programs were higher than in non-face-to-face exercise programs (p < .05). The main source of dissatisfaction in the case of face-to-face exercise programs was having a good relationship with people for face-to-face and a ‘lack of communication’ in the case of non-face-to-face. CONCLUSION: The elderly showed higher satisfaction in face-to-face exercise than in non-face-to-face exercise. This study is significant in that accurate satisfaction comparison was possible by conducting the same exercise program on the same subject for a relatively short time, and through this, the development of an exercise program was suggested.