All existing left ventricular assist devices (LVADs) need inlet and outlet connecting con-duits and the assist pumping blood flows through the bypass circuit from left ventricle to aorta. It will result in some most l...All existing left ventricular assist devices (LVADs) need inlet and outlet connecting con-duits and the assist pumping blood flows through the bypass circuit from left ventricle to aorta. It will result in some most likely sites of thrombosis and brings about physiological dis-turbance to natural circulation, as well as addi-tional need for anatomic occupation in chest. The author developed a trans-apical and cross-valvular intra-ventricular axial pump and an aortic valvo- pump to solve these problems. The intra-ventricular pump weighing 53g has a length of 115mm and its largest O.D. is 13mm. The motor is 60mm long and the pump 55mm. In both sides of motor, specially designed needle bearings are devised and a purge system keeps the motor together with bearings working in sa-line. The device is inserted into the ventricle by trans-apex and then into the aorta by cross-valve. It is used for recovery therapy or bridge to transplantation. The bearing-less valvo-pumps have an outer diameter of 21mm, 23mm or 25mm for patients with different body weights. The weight of the devices is 27g, 31g or 40g respectively. Used for destination therapy it can be easily sewed onto the aortic valve annu-lus, delivers blood from ventricle to aorta di-rectly. These two novel mini LVADs may reduce thrombosis risk in clinical applications.展开更多
This study aimed to explore the characteristics of perioperative nursing of experimental goats using self-made axial-flow blood pump implantation and provided theoretical nursing knowledge and practice-based evidence ...This study aimed to explore the characteristics of perioperative nursing of experimental goats using self-made axial-flow blood pump implantation and provided theoretical nursing knowledge and practice-based evidence for the clinical application of domestically manufactured artificial cardiac pumps. Methods: Seven experimental goats were used in this study, three for pre-testing and four for the formal experiments. According to the surgical requirements for axial-flow blood pump implantation into the cardiac apex, we creatively designed and made a series of highly practical animal surgical instruments including a composite disassemblable bed for experimental animal transferring and monitoring, a multifunctional animal surgery bed, and portable medical supporting equipment. We also applied for two national invention patents and one utility model patent. Active measures were taken to ensure careful preparation before surgery, close collaboration during surgery, and effective management of complications after surgery. Results: Two of the four experimental goats died during surgery because of a massive hemorrhage caused by distal anastomotic failure and air embolism-induced cardiac arrest caused by air leakage from the outlet into the heart due to poor connection of the auxiliary pressure tap (used to measure left ventricular pressure). The mean survival time of the remaining three experimental goats was 22.7 hours. Conclusion: This study was the first to systematically and comprehensively investigate the perioperative nursing management of axial-flow blood pump implantation using animal models. These findings could greatly promote further clinical applied nursing research of self-made artificial cardiac pump implantation in experimental goats.展开更多
Reduced order modeling(ROM)techniques are numerical methods that approximate the solution of parametric partial differential equation(PED)by properly combining the high-fidelity solutions of the problem obtained for s...Reduced order modeling(ROM)techniques are numerical methods that approximate the solution of parametric partial differential equation(PED)by properly combining the high-fidelity solutions of the problem obtained for several configurations,i.e.for several properly chosen values of the physical/geometrical parameters characterizing the problem.By starting from a database of high-fidelity solutions related to a certain values of the parameters,we apply the proper orthogonal decomposition with interpolation(PODI)and then reconstruct the variables of interest for new values of the parameters,i.e.different values from the ones included in the database.Furthermore,we present a preliminary web application through which one can run the ROM with a very user-friendly approach,without the need of having expertise in the numerical analysis and scientific computing field.The case study we have chosen to test the efficiency of our algorithm is represented by the aortic blood flow pattern in presence of a left ventricular(LVAD)assist device when varying the pump flow rate.展开更多
Treatment of ischemic stroke for a patient on left ventricular assist device (LVAD) by neurointerventional means is rare and many anesthesia providers are unfamiliar with both LVAD and neurointerventional protocols. E...Treatment of ischemic stroke for a patient on left ventricular assist device (LVAD) by neurointerventional means is rare and many anesthesia providers are unfamiliar with both LVAD and neurointerventional protocols. Examples of this include: 1) filling for continuous-flow LVAD depend on preload and the flow is inversely related to afterload;as mean arterial pressure (MAP) increases above 80 to90 mmHg, flow decreases;2) there may be no palpable pulse in patients with continuous flow LVADs;3) pulse oximetry may not work when pump flow is high and native myocardial function is minimal;4) increasing MAP above80 mmHg potentially will maintain ischemic brain tissue—the penumbra—until flow is restored. This latter example creates a paradoxical management goal: increasing the mean arterial pressure (MAP) above80 mmHg while maintaining ischemic brain tissue, may decrease flow to the LVAD. Finally, there is controversy regarding which type of anesthesia is most efficacious for neuro interventional procedures. We describe three patients on LVAD suffering ischemic stroke requiring anesthesia for embolectomy and angioplasty during neruointeventioal radiology procedures.展开更多
Gastrointestinal bleeds are a commonly observed complication after left ventricular assist device placement and usually caused by formation of arteriovenous malformations or acquired von Willebrand disease in the sett...Gastrointestinal bleeds are a commonly observed complication after left ventricular assist device placement and usually caused by formation of arteriovenous malformations or acquired von Willebrand disease in the setting of anticoagulation use. We present a unique case of an upper GI bleed in which the cause was likely due to the impaction of a guitar pick into the duodenal bulb in the setting of continuous flow-LVAD on anticoagulation with elevated INR and discuss the pathophysiology of GI bleeds post-LVAD placement and relevant concerns about finding foreign bodies in the GI tract and their complications.展开更多
心力衰竭（心衰）患者延长左室辅助装置（LVAD）使用，可能有助于成人心肌再生。德克萨斯大学西南医学中心Hesham A. Sadek博士，“新数据表明，去负荷后的逆重构可能代表了心肌从肥厚到增生的转换”。该结果发表在2015年的JACC杂志上...心力衰竭（心衰）患者延长左室辅助装置（LVAD）使用，可能有助于成人心肌再生。德克萨斯大学西南医学中心Hesham A. Sadek博士，“新数据表明，去负荷后的逆重构可能代表了心肌从肥厚到增生的转换”。该结果发表在2015年的JACC杂志上。 成人心肌细胞不能分裂，因此成人心脏在大量心肌细胞损失后不能再生。既往研究证实，线粒体介导的氧化DNA损伤在出生后心肌细胞周期停滞中发挥重要作用。Sadek和同事开展的这项研究旨在观察机械负荷是否在其中也起作用，并假设机械负荷的生理性增加导致了线粒体含量增多，使DNA损伤应答激活，带来永久性心肌细胞周期停滞。展开更多
文摘All existing left ventricular assist devices (LVADs) need inlet and outlet connecting con-duits and the assist pumping blood flows through the bypass circuit from left ventricle to aorta. It will result in some most likely sites of thrombosis and brings about physiological dis-turbance to natural circulation, as well as addi-tional need for anatomic occupation in chest. The author developed a trans-apical and cross-valvular intra-ventricular axial pump and an aortic valvo- pump to solve these problems. The intra-ventricular pump weighing 53g has a length of 115mm and its largest O.D. is 13mm. The motor is 60mm long and the pump 55mm. In both sides of motor, specially designed needle bearings are devised and a purge system keeps the motor together with bearings working in sa-line. The device is inserted into the ventricle by trans-apex and then into the aorta by cross-valve. It is used for recovery therapy or bridge to transplantation. The bearing-less valvo-pumps have an outer diameter of 21mm, 23mm or 25mm for patients with different body weights. The weight of the devices is 27g, 31g or 40g respectively. Used for destination therapy it can be easily sewed onto the aortic valve annu-lus, delivers blood from ventricle to aorta di-rectly. These two novel mini LVADs may reduce thrombosis risk in clinical applications.
文摘This study aimed to explore the characteristics of perioperative nursing of experimental goats using self-made axial-flow blood pump implantation and provided theoretical nursing knowledge and practice-based evidence for the clinical application of domestically manufactured artificial cardiac pumps. Methods: Seven experimental goats were used in this study, three for pre-testing and four for the formal experiments. According to the surgical requirements for axial-flow blood pump implantation into the cardiac apex, we creatively designed and made a series of highly practical animal surgical instruments including a composite disassemblable bed for experimental animal transferring and monitoring, a multifunctional animal surgery bed, and portable medical supporting equipment. We also applied for two national invention patents and one utility model patent. Active measures were taken to ensure careful preparation before surgery, close collaboration during surgery, and effective management of complications after surgery. Results: Two of the four experimental goats died during surgery because of a massive hemorrhage caused by distal anastomotic failure and air embolism-induced cardiac arrest caused by air leakage from the outlet into the heart due to poor connection of the auxiliary pressure tap (used to measure left ventricular pressure). The mean survival time of the remaining three experimental goats was 22.7 hours. Conclusion: This study was the first to systematically and comprehensively investigate the perioperative nursing management of axial-flow blood pump implantation using animal models. These findings could greatly promote further clinical applied nursing research of self-made artificial cardiac pump implantation in experimental goats.
基金supported by the European Research Council Executive Agency by the Consolidator Grant project AROMA-CFD“Advanced Reduced Order Methods with Applications in Computational Fluid Dynamics”--GA 681447,H2020-ERC CoG 2015 AROMA-CFD and INdAM-GNCS 2020 project“Tecniche Numeriche Avanzate per Applicazioni Industriali”。
文摘Reduced order modeling(ROM)techniques are numerical methods that approximate the solution of parametric partial differential equation(PED)by properly combining the high-fidelity solutions of the problem obtained for several configurations,i.e.for several properly chosen values of the physical/geometrical parameters characterizing the problem.By starting from a database of high-fidelity solutions related to a certain values of the parameters,we apply the proper orthogonal decomposition with interpolation(PODI)and then reconstruct the variables of interest for new values of the parameters,i.e.different values from the ones included in the database.Furthermore,we present a preliminary web application through which one can run the ROM with a very user-friendly approach,without the need of having expertise in the numerical analysis and scientific computing field.The case study we have chosen to test the efficiency of our algorithm is represented by the aortic blood flow pattern in presence of a left ventricular(LVAD)assist device when varying the pump flow rate.
文摘Treatment of ischemic stroke for a patient on left ventricular assist device (LVAD) by neurointerventional means is rare and many anesthesia providers are unfamiliar with both LVAD and neurointerventional protocols. Examples of this include: 1) filling for continuous-flow LVAD depend on preload and the flow is inversely related to afterload;as mean arterial pressure (MAP) increases above 80 to90 mmHg, flow decreases;2) there may be no palpable pulse in patients with continuous flow LVADs;3) pulse oximetry may not work when pump flow is high and native myocardial function is minimal;4) increasing MAP above80 mmHg potentially will maintain ischemic brain tissue—the penumbra—until flow is restored. This latter example creates a paradoxical management goal: increasing the mean arterial pressure (MAP) above80 mmHg while maintaining ischemic brain tissue, may decrease flow to the LVAD. Finally, there is controversy regarding which type of anesthesia is most efficacious for neuro interventional procedures. We describe three patients on LVAD suffering ischemic stroke requiring anesthesia for embolectomy and angioplasty during neruointeventioal radiology procedures.
文摘Gastrointestinal bleeds are a commonly observed complication after left ventricular assist device placement and usually caused by formation of arteriovenous malformations or acquired von Willebrand disease in the setting of anticoagulation use. We present a unique case of an upper GI bleed in which the cause was likely due to the impaction of a guitar pick into the duodenal bulb in the setting of continuous flow-LVAD on anticoagulation with elevated INR and discuss the pathophysiology of GI bleeds post-LVAD placement and relevant concerns about finding foreign bodies in the GI tract and their complications.
文摘心力衰竭（心衰）患者延长左室辅助装置（LVAD）使用，可能有助于成人心肌再生。德克萨斯大学西南医学中心Hesham A. Sadek博士，“新数据表明，去负荷后的逆重构可能代表了心肌从肥厚到增生的转换”。该结果发表在2015年的JACC杂志上。 成人心肌细胞不能分裂，因此成人心脏在大量心肌细胞损失后不能再生。既往研究证实，线粒体介导的氧化DNA损伤在出生后心肌细胞周期停滞中发挥重要作用。Sadek和同事开展的这项研究旨在观察机械负荷是否在其中也起作用，并假设机械负荷的生理性增加导致了线粒体含量增多，使DNA损伤应答激活，带来永久性心肌细胞周期停滞。
