• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.11b
• /
• pp.292-295
• /
• 2001

The NdBaCuO superconducting samples were prepared by the Zone melting under low oxygen partial pressure. After the zone-melting the oxygenation process of the NdBaCuO samples in a oxygen flow furnace was studied. In order to compare the oxygenation condition the sintering NdBaCuO samples were studied also. In the study it is found that the optimum temperature for the oxygenation is $350^{\circ}C$, and the oxygen flow speed, the sample volume and the surface area of the sample would influence the oxygenation and the oxygen content.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.11a
• /
• pp.292-295
• /
• 2001

The NdBaCuO superconducting samples were prepared by the Zone melting under low oxygen partial pressure. After the zone-melting the oxygenation process of the NdBaCuO samples in a oxygen flow furnace was studied. In order to compare the oxygenation condition the sintering NdBaCuO samples were studied also. In the study it is found that the optimum temperature for the oxygenation is $350{\circ}C$, and the oxygen flow speed, the sample volume and the surface area of the sample would if1uence the oxygenation and the oxygen content.

• Journal of Chest Surgery
• /
• v.27 no.1
• /
• pp.60-62
• /
• 1994

Pulmonary edema and respiratory failure is uncommon but fatal complications associated with major operations of the lung, especially after pneumonectomy. The extracorporeal membrane oxygenation[ECMO] is quite often used in infants with severe respiratory failure and congenital heart disease which is well documented in the literature. In adults, the results of ECMO is comparatively poor to those found in neonates. We have experienced a case of ECMO applied on a 48 year old male who had respiratory failure after pneumonectomy, and the patient was successfully weaned from bypass. Unfortunately however, the patient expired on postoperative 15 day due to multiorgan failure.

• Tuberculosis and Respiratory Diseases
• /
• v.84 no.2
• /
• pp.115-124
• /
• 2021

Background: This study aimed to determine the parameters for worsening oxygenation in non-severe coronavirus disease 2019 (COVID-19) pneumonia. Methods: This retrospective cohort study included cases of confirmed COVID-19 pneumonia in a public hospital in South Korea. The worsening oxygenation group was defined as that with SpO₂ ≤94% or received oxygen or mechanical ventilation (MV) throughout the clinical course versus the non-worsening oxygenation group that did not experience any respiratory event. Parameters were compared, and the extent of viral pneumonia from an initial chest computed tomography (CT) was calculated using artificial intelligence (AI) and measured visually by a radiologist. Results: We included 136 patients, with 32 (23.5%) patients in the worsening oxygenation group; of whom, two needed MV and one died. Initial vital signs and duration of symptoms showed no difference between the two groups; however, univariate logistic regression analysis revealed that a variety of parameters on admission were associated with an increased risk of a desaturation event. A subset of patients was studied to eliminate potential bias, that ferritin ≥280 ㎍/L (p=0.029), lactate dehydrogenase ≥240 U/L (p=0.029), pneumonia volume (p=0.021), and extent (p=0.030) by AI, and visual severity scores (p=0.042) were the predictive parameters for worsening oxygenation in a sex-, age-, and comorbid illness-matched case-control study using propensity score (n=52). Conclusion: Our study suggests that initial CT evaluated by AI or visual severity scoring as well as serum markers of inflammation on admission are significantly associated with worsening oxygenation in this COVID-19 pneumonia cohort.

• Archives of Plastic Surgery
• /
• v.35 no.5
• /
• pp.495-500
• /
• 2008

Purpose: Adequate tissue oxygenation is considered as an essential factor for wound healing. In the non-diabetic population, an uncompromised macrocirculation generally leads to adequate tissue oxygenation. On the contrary, the macrocirculation in diabetic patients may not correlate with tissue oxygenation because of structural changes in the capillary basement membrane. Nevertheless, many medical professionals in Korea rely on macrocirculation evaluation when predicting wound healing potential of the diabetic ulcers. The purpose of this study is to compare reliability of two common macrocirculation assessment methods, Doppler probing and CT angiography, on tissue oxygenation in diabetic foot patients. Methods: Doppler and CT angiography scores were given according to the patency of the anterior and posterior tibial arteries. Tissue oxygenation was measured by transcutaneous partial oxygen tension($TcpO_2$). Doppler and CT angiography scores were statistically analyzed against $TcpO_2$ values. Sixty-eight diabetic foot ulcer patients were included in this study. Results: The test was carried out on Doppler score and $TcpO_2$ variables displayed a p-value of 0.0202, and concluded that the two variables were statistically dependent. The test used to determine for linear trends between Doppler scores and $TcpO_2$ variables displayed a p-value of 0.0149, displaying statistical linear trend between the two variables. On the contrary, the tests between CT angiography scores and $TcpO_2$ variables showed p-values of 0.1242 and 0.6590, that means no correlation between CT angiography and $TcpO_2$ scores. Conclusion: Doppler probing is more reliable than CT angiography in predicting tissue oxygenation of diabetic foot ulcers.

• Tuberculosis and Respiratory Diseases
• /
• v.72 no.1
• /
• pp.1-7
• /
• 2012

Extracorporeal Membrane Oxygenation (ECMO) support to tissue oxygenation has been shown to improve survival in patients with life threatening respiratory distress syndrome or cardiac failure. Extracorporeal life support such as ECMO, including extracorporeal $CO_2$ removal ($ECCO_2R$), is used as temporary support until successful recovery of organs. A recently published multicentre randomized controlled trial, known as the CESAR (conventional ventilation or extracorporeal membrane oxygenation for severe adult respiratory failure) trial, was the first trial to demonstrate the utility of ECMO in acute respiratory distress syndrome (ARDS). During the 2009 influenza A (H1N1) pandemic, there were many reports of patients with severe ARDS related to H1N1 infection treated with ECMO. These reports revealed a high survival rate and effectiveness of ECMO. In this review, we explain the indication of ECMO clinical application, the practical types of ECMO, and complications associated with ECMO. In addition, we explain recent new ECMO technology and management of patients during ECMO support.

• Journal of Yeungnam Medical Science
• /
• v.36 no.3
• /
• pp.254-259
• /
• 2019

Pheochromocytoma (PCC) is a rare catecholamine-producing tumor with the incidence in hypertension of 0.1-0.6%. PCC crisis is an endocrine emergency that can lead to hemodynamic disturbance and organ failure such as catecholamine-induced cardiomyopathy. The circulatory collapse caused by it often requires mechanical support. The author reports an unusual case in which a patient who previously underwent surgery for malignant PCC developed catecholamine-induced cardiomyopathy, and successfully recovered using extracorporeal membrane oxygenation.

• Kosin Medical Journal
• /
• v.33 no.3
• /
• pp.477-482
• /
• 2018

Intraoperative pulmonary thromboembolism is a high mortality situation. Early mortality in patients with pulmonary thromboembolism varies from 2% in normotensive patients to 30% in patients with cardiogenic shock. The use of extracorporeal cardiopulmonary resuscitation can improve survival and neurologic outcomes of cardiac arrest. We report a case of intraoperative massive pulmonary thromboembolism with circulatory collapse and cardiac arrest during anesthesia for pelvic bone fracture surgery, which were rescued by extracorporeal membrane oxygenation.

• Journal of Chest Surgery
• /
• v.25 no.11
• /
• pp.1203-1208
• /
• 1992

Current methods of myocardial protection has been improved with cardioplegia and hypothermia. We compared St. Thomas hospital cardiopleic solution without oxygenation[Group I], with oxygenation[Group II] and with oxygenation with filter[Group III] under isolated working heart model. Heart rate recovery was more significantly improved in Group II than Group I after 15 minutes of recovery time [p<0.05]. Maximal systolic pressure shows no difference as it increases with time. Cardiac ouputs were not diffrent between groups. Recovery time was shorter significantly in group II and group III than group I [p<0.05] Use of filter showed no difference. As a conclusion, oxygenated cardioplegic solutions improves ability to protect the heart against ischemia and it is manifested by improved recovery time and heart rate.

• Journal of Biomedical Engineering Research
• /
• v.17 no.2
• /
• pp.227-234
• /
• 1996

This paper is the study of the diffusion constant in order to calculate the percent oxygenation and percent blood volume using reflectance light within biological tissue. The diffusion constant play major role in percent oxygenation and percent blood volume and varies with the biological material such as hemolyzed blood, whole blood, dermis and epidermis in vivo tissue. The diffusion constant can be modeled to consist of a contribution from bloodless tissue and blood present in tissue. The reflectance light for experimental are red light of 660nm, infrared light of 880nm, green light of 569nm. The correlation between the diffusion constant and biological tissue was analyzed by the intensity of reflectance light at different depth within human limb. The reflectance light was changed in response to physiological changes within biological tissue. The data for diffusion constant were obtained at different depth beneath the surface of the skin and will be utilized to amen the percent oxygenation and percent blood volume.