• Journal of Chest Surgery
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• v.38 no.12 s.257
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• pp.807-814
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• 2005

Background: Cardiopulmonary bypass is an essential process to maintain circulation for saving life during the cardiac surgery, But it is a process in which systemic inflammation was evoked inevitably because of the exposure of blood to foreign surface. The injuries to distal organs during the cardiopulmonary bypass were resulted from systemic inflammation and the disturbances of micro-circulations in the organs. We designed this study to research the effects of leukocyte depletion from pump-oxygenator priming solution on the systemic inflammation, and the micro-circulation of gastric mucosa that is suggested by the gastric mucosal $CO_{2}$ partial pressure and acidity. Material and Method: The dogs were divided into three groups according to the different pump-oxygenator priming solutions; non-hemic crystalloid solution; leukocyte-depleted homologous blood; and non leukocyte-depleted homo-logous blood. Each priming solution group contained five dogs. In all three groups, 2 hours of cardiopulmonary bypass, and 4 consecutive hours of general anesthesia was maintained on the mechanical ventilation. Each dog was evaluated for the gastric mucosal pH, $CO_{2}$ partial Pressure, arterial pH, $CO_{2}$ partial pressure, the exhaled air $CO_{2}$ partial pressure and the level of IL-8 on before the cardiopulmonary bypass, 1 hour after the cardiopulmonary bypass, 2 hours after the cardiopulmonary bypass, 2 hours after the restoration of normal circulation, and 4 hours after the restoration of normal circulation after the cardiopulmonary bypass. The levels of IL-8 were measured with ELISA (enzyme linked immunosorbent assay) technique. Result: 1. There were significant differences of gastric mucosal $CO_{2}$ partial pressure between the leukocyte-depleted homologous blood group and other two groups(vs non leukocyte-depleted homologous blood group; P=0.02, vs non-hemic crystalloid solution group; P=0,01). 2. The gastric mucosal pH of leukocyte-depleted homologous blood group was significantly different from non leukocyte-depleted homologous blood group (p=0.01). 3. The levels of IL-8, which examine the systemic inflammation, showed signi- ficantly better results in leukocyte-depleted homologous blood group and non-hemic crystalloid solution group than non leukocyte-depleted homologous blood group (p=0.01, 0.01). Conclusion: Based upon these results, we concluded that the leukocyte depletion from the pump-oxygenator priming solution has a beneficial effects in reducing systemic inflammation and the preserving of gastric mucosal micro-circulation.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.489-492
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• 2002

The objective of the present study were to measure the viscosities of non-Newtonian fluids by the transient flow concept in a capillary tube and to apply to hemodynamic studies and pump performance evaluations. The developed capillary tube viscometer could be used to measure the viscosities of the non-Newtonian fluids for a wide range of the shear rate by a run of experiment in a very short time interval. The measured viscosities of water and blood fur different shear rates were good agreement with those of the well established data. The measured viscosities for muddy water varied with the shear rates.

• Journal of Chest Surgery
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• v.28 no.1
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• pp.7-10
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• 1995

Mixed Venous oxygenation saturation[SvO2 is a variable determined in part by the externally controlled factors and in part by the patient during CPB. I monitored the SvO2 and tested it as a parameter for the regulation of pump output and as a criteria for the need of inotropics after CPB. With the help of SvO2, I increased the pump flow especially during rewarming for more optimal oxygenation of cells. After CPB, the calculated cardiac index was used as an indicator for the need of inotropic support with greater accuracy and without any clinical problems. I conclude that the SvO2 is an easily checkable variable and a good indicator for optimal oxygenation at cell level, and can be used as an objective criteria for the need of postoperative inotropic support.

• Korean Journal of Acupuncture
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• v.33 no.2
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• pp.58-66
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• 2016

Objectives : In order to find a possible non-invasive manipulation tool for maintenance of the cardiovascular functions in hemorrhagic shock, this study was aimed at evaluating effects of acupoints acupressure on the changes in blood pressure and heart rate from an animal model of hemorrhagic shock. Methods : In adult Sprague-Dawley rats, hemorrhagic shock was induced by a withdrawal of arterial blood from the femoral artery with volume of 0.8 ml per 100 g of body weight using peristaltic syringe pump. We applied the acupressure with a pressure oscillator to tail as a control and 2 different acupoints of sobu(HT8), youngchun(KI1) under 3 different conditions : 1) normal arterial blood pressure without bleeding, 2) at the beginning of bleeding, and finally 3) hemorrhagic shock. Results : Under normal arterial blood pressure without hemorrhage, there was a significant increase in systolic and diastolic blood pressures by the acupressure to the tail, HT8 and especially KI1 for 30 sec compared with before acupressure. Under hemorrhagic shock condition, the tail acupressure had minimal changes in cardiovascular parameters. Either the HT8 or KI1 acupressure resulted in a significant increase in arterial pressure but did not heart rate. At the beginning of bleeding, tail acupressure failed to change the reduction of arterial pressure and heart rate. However, there was a significant increase in blood pressure and heart rate following either the HT8 or especially KI1 acupressure. Conclusions : HT8 and KI1 acupressure affected cardiovascular signs but tail acupressure did not in rat model of hemorrhagic shock. These experimental data suggest that a acupressure with a pressure oscillator to HT8 or KI1 can be one of alternative emergency manipulations to ameliorate compromised cardiovascular functions under hemorrhagic shock condition.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.6
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• pp.705-714
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• 1998

Cerebral blood vessels relax when extracellular $K^+$ concentrations $([K^+])_e$ are elevated moderately $(2{\sim}15$ mM, $K^+-induced$ vasorelaxation). We have therefore studied the underlying mechanism for this $K^+-induced$ vasorelaxation in the isolated middle cerebral arteries (MCAs). The effects of ouabain and $Ba^{2+}\;on\;K^+-induced$ vasorelaxation were examined to determine the role of sodium pump and/or Ba-sensitive process (possibly, inward rectifier K current) in the mechanism. Mulvany myograph was used to study 24 rats, 18 rabbits, and 10 humans MCAs $(216{\pm}3\;{\mu}m,\;347{\pm}7\;{\mu}m,\;and\;597{\pm}39\;{\mu}m$ in diameter when stretched to a tension equivalent to 55 mmHg). High $K^+$ (125 mM) and $PGF_{2{\alpha}}\;(1{\sim}10\;{\mu}M)$ induced concentration-dependent contractions in all 3 species, while histamine $(10{\sim}50\;{\mu}M)$ evoked contraction only in the rabbits and induced relaxation in the rats and humans. Addition of $K^+\;(2{\sim}10\;{\mu}M)$ to the control solution induced vasorelaxations. These effects were inhibited by the pretreatment with both ouabain $(10\;{\mu}M)$ and $Ba^{2+}\;(0.1{\sim}0.3\;mM)$ in the rat, but only with ouabain $(10\;{\mu}M)$ in the rabbit and human. These results suggest that $K^+-induced$ vasorelaxation occurs via the stimulation of electrogenic Na pump in the rabbit and human MCAs, while in the rat MCAs via the activation of both Na pump and Ba-sensitive process.

• Journal of Biomedical Engineering Research
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• v.43 no.4
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• pp.214-218
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• 2022

The purpose of this study was to investigate the role of the PMF in the treatment of acidosis and inflammation by monitoring the pH change for the continuity of PMF effect on the blood in the micro-circulation system that mimics the capillaries in the human body. Micro-tubes and micro-channels similar in diameter to those of arteries and arterioles were fabricated using PDMS and connected to a micro-pump for blood circulation. The continuity of PMF effect was verified in a micro-circulation system in-vitro. The pH changes for the circulating blood and for persistence time of PMF stimulus effect were confirmed using the optimized PMF conditions based on the previous studies. Also pH changes were observed by continuously stimulating PMF for a set period of time. The result was observed that the pH of the blood acidified using tBHP continued to rise from immediately after stimulation of PMF to 70 minutes of stimulation, reaching a normal pH range, and then decreasing. Our study showed that PMF has a positive effect on the control of blood pH homeostasis, so it is suggested the possibility of being used as a noninvasive treatment for acidosis treatment and anti- inflammatory treatment.

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.238.1-238.1
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• 2001

• Journal of Chest Surgery
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• v.34 no.9
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• pp.704-710
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• 2001

Background: Extracorporeal circulation using pump-oxygenator is an inevitable process to keep vital sign during cardiac arrest for open heart surgery. However, the diversion of blood through nonendothelialized channels appears to stimulate inflammatory response, and leukocyte activation may lead to cardiopulmonary edema. Our study evaluated the effect of leukocyte-induced cardiopulmonary edema using three different pump-oxygenator priming solutions; non-hemic crystalloid solution ; leukocyte-depleted homologous blood; non leukocyte-depleted homologous blood in priming solutions. Material and Method: Each different priming solution was used on five dogs, and the effect of leukocyte-induced cardiopulmonary edema during cardiopulmonary bypass(CPB) was evaluated. For each dog after 2 hours of exracorporeal circulation and another 4 hours of post-pump period, the dog was sacrificed and its heart and lung tissues were obtained for measuring Wet/Dry ratio. Arterial $O_2$partial pressure(PaO$_2$) and $CO_2$partial pressure(Pa$CO_2$) were checked. For the evaluation of ventilatory function, $CO_2$partial pressure difference between arterial blood (Pa$CO_2$) and exhaled air(Et$CO_2$) was measured. Result: 1. No significant difference was seen in arterial PaO$_2$and Pa$CO_2$among groups. 2. Ventilatory function evaluated by Pa$CO_2$and Et$CO_2$showed no significant difference between non-hemic and blood-mixed priming solution (P<0.05). 3. Cardiac and lung Wet/Dry ratios were remarkedly lower in the leukocyte-depleted group. There was no significant difference between the non-hemic and blood-mixed groups. Conclusion: Based upon this result, we concluded that the leukocyte depletion from homologous blood of CPB priming solution has a beneficial effect in reducing cardiopulmonary edema compared with non leukocyte-depleted or crystalloid priming solutions.

• The Korean Journal of Physiology
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• v.9 no.1
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• pp.33-37
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• 1975

Adult rabbits were anesthetized with nembutal, 30 mg/kg. Carotid artery and jugular vein were exposed surgically and cannulated with polyethylene tubing. Arterial blood pressure was recorded via pressure transducer on the physiograph and $100{\mu}g/ml$ of histamine solution was infused through the jugular vein by using the constant infusion pump with a rate of 0.92 ml/min or 1.40 ml/min. Mean arterial blood pressure was maintained at $40{\sim}70 mmHg$ and hypotension was kept for 2 hours. After the termination of this period, blood was taken and osmotic fragility was mea sured immediately. Also, every sample of normal blood and shocked blood was incubated for 1 hour or 2 hours at $37^{\circ}C$ in order to see whether or not there was some influence of incubation. Furthermore to clarify which component was responsible for the change on the fragility, the mixtures of normal blood cells with shocked plasma and shocked blood cells with normal plasma were also incubated at $37^{\circ}C$ for one or two hours and fragility in such cases was measured. The data obtained were analysed by probit-plot method and the concentration of saline solution at which the hemolysis started to occur, 50% of blood cells were hemolysed and that at which the red blood cells hemolysed completely were determined. The values for the blood of hypotension stage were compared with those of the control blood. The results obtained were as fellows: 1. Osmotic fragility of red blood cell was increased in hypotensive state induced by histamine. 2. The differences of osmotic fragility after two hours of incubation were negligible both in normal blood and in that of hypotensive state. 3. Osmotic resistance of normal red blood cell incubated in shock plasma was less than that of shock red blood cell incubated in normal plasma. It was suggested that plasma in hypotensive state caused by histamine might be primarily responsible for the alteration of red blood cell fragility.

• The Journal of the Acoustical Society of Korea
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• v.36 no.5
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• pp.361-369
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• 2017

Hemodynamic information in the carotid artery bifurcation is very important for understanding the development and progression mechanisms of cerebrovascular disease and for its early diagnosis and prediction of the progress. In this paper, we constructed a mock pulsatile blood circulation system using an anthropomorphic elastic vessel of the carotid artery bifurcation and ex vivo pig blood to acquire ultrasound images from blood and vessels synchronized with internal pressure while controlling the blood flow. Echogenicity, blood flow velocity, and blood vessel wall motion from the ultrasound images, and internal blood pressure were extracted over a cycle averaged from five cycles when the pulsatile pump rates are 20 r/min, 40 r/min, and 60 r/min. As a result, respectively, the peak systolic blood flow velocities were 20 cm/s, 25 cm/s, and 40 cm/s, the blood pressure differences were 30 mmHg, 70 mmHg, and 85 mmHg, the arterial walls were expanded to 0.05 mm, 0.15 mm, and 0.25 mm. Time-delayed cyclic variation of echogenicity compared to blood flow and pressure was observed, but the variation was minimal at 20 r/min. Time-synchronized cyclic variations of these parameters are important information for accurate input parameters and validation of the computational hemodynamic experiments which will provide useful information for the development and progress mechanisms of carotid artery stenosis.