1.Research on the Incentive Mechanism of Human Organ Donation
Jinping ZHAO ; Jufang WU ; Yunzhang LIU
Chinese Medical Ethics 1994;0(05):-
The lack of organs has been an crucial limiting factor for Chinese organ transplantation,thus it is in urgent need to effectively increase the number of donor organs.This article holds that,besides through publicity and education to promote unpaid voluntary organ donation,some incentive mechanisms are also required to serve as useful complements.Therefore,organs' origin can be expanded to a certain extent,and the intense supply and demand in organ transplantation can also be eased.Unifying organ transplantation practice in China,this paper explains the necessity of organ donation incentive mechanisms from both theoretical and practical significances,reveals the main elements of the incentive mechanisms,and explores the realization means.
2.The numerical simulation of the internal flow field inside the pressure generator of a continuous positive airway pressure ventilator.
Yunzhang CHENG ; Lihua ZHU ; Weiguo ZHANG ; Wenquan WU
Journal of Biomedical Engineering 2011;28(6):1131-1135
The problem of noise in ventilator has always been an important topic to study in the development of the ventilator. A great number of data are showing that there are still large gaps of research and application levels in noise control of the ventilator between China and some more advanced foreign countries. In this study, with cooperation of the Shanghai Medical Equipment Limited Liability Company, we used the computational fluid dynamics (CFD), software FLUENT, adopted the standard k-epsilon turbulence model and the SIMPLE algorithm to simulate the inner flow field of the continuous positive airway pressure (CPAP) ventilator's pressure generator. After a detailed analysis, we figured out that there are several deficiencies in this ventilator, like local reflow in volute, uneven velocity distribution and local negative pressure in inlet of the impeller, which easily lead to noise and affect the ventilator's performances. So, it needs to be improved to a certain extent.
Algorithms
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Computer Simulation
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Continuous Positive Airway Pressure
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adverse effects
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instrumentation
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Equipment Design
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methods
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Models, Theoretical
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Noise
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prevention & control
3.Research on flow characteristics in a non-blade centrifugal blood pump based on CFD technology.
Yunzhang CHENG ; Binhai LUO ; Wenquan WU ; Lei JIANG
Journal of Biomedical Engineering 2010;27(5):1133-1137
The problem of thrombus and hemolysis in blood pump has always been an important topic to study in the development of the blood pump. Numbers of research results show that it is the complicated flow and the high shear stress of the mechanical movement that result in the thrombus and hemolysis. In this study, with the cooperation of Shanghai Children's Medical Center, we have used computational fluid dynamics (CFD) commercial software FLUENT to compute and analyze the flow characteristics in a non-blade centrifugal blood pump. The results figure out that this pump has a reasonable flow distribution and the shear stress distribution is under the critical broken state of red blood cell; meanwhile, there is less thrombus and hemolysis in this pump. So it is in the foreground for clinical use.
Computer Simulation
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Heart Defects, Congenital
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therapy
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Heart-Assist Devices
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adverse effects
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Hemodynamics
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Hemolysis
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Hemorheology
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Humans
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Models, Theoretical
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Stress, Mechanical
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Thrombosis
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prevention & control
4.Short- to medium-term safety and efficacy of the implantable Corheart 6 left ventricular assist system in patients with end-stage heart failure
Zhibing QIU ; Xiaochun SONG ; Liangpeng LI ; Hongwei SHI ; Liqiong XIAO ; Yunzhang WU ; Xiaosong RONG ; Jidan FAN ; Liang WEI ; Xin CHEN
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2025;32(05):639-645
Objective To investigate the efficacy and safety of the Corheart 6 left ventricular assist system in patients with end-stage heart failure. Methods A retrospective study was conducted on patients with end-stage heart failure who were treated with Corheart 6 left ventricular assist system from March 2022 to June 2024 in 4 hospitals in Jiangsu Province. The efficacy of the device was evaluated by comparing changes in clinical indicators at preoperative, discharge, 3-month postoperative, and 6-month postoperative timepoints, including the New York Heart Association (NYHA) functional classification, left ventricular ejection fraction (LVEF), and left ventricular end-diastolic diameter (LVEDD). The safety of the device was assessed by analyzing the intraoperative position and orientation of the blood pump inlet cannula, as well as the incidence of adverse events. Results In this study, 39 patients were collected, including 34 males and 5 females with a mean age of (56.4±12.5) years, ranging from 20 to 75 years. There was no operative death. There was no death in postoperative 3 months with a survival rate of 100.0%. There were 3 deaths in 6 months postoperatively, with a survival rate of 92.3%. All patients had a preoperative NYHA cardiac function classification of class Ⅳ. The NYHA cardiac function class of the patients improved (P<0.05) at discharge, 3 and 6 months after surgery when compared to the preoperative period. LVEF was significantly higher at 3 months after surgery than that during the preoperative period (P<0.05). LVEDD was significantly smaller at discharge, 3 and 6 months after surgery than that during the preoperative period (P<0.05). The safety evaluation's findings demonstrated that all 39 patients' intraoperative blood pump inlet tubes were oriented correctly, the artificial blood vessel suture sites were appropriate, there were no instances of device malfunction or pump thrombosis, or instances of bleeding or hemolysis, and the rate of the remaining adverse events was low. Conclusion With a low rate of adverse events and an excellent safety profile, the Corheart 6 left ventricular assist system can efficiently enhance cardiac function in patients with end-stage heart failure. It also has considerable clinical uses.