scholarly journals PROSPECTS OF DISK PUMP FOR MECHANICAL CIRCULATORY SUPPORT IN CARDIAC SURGERY (REVIEW)

2016 ◽  
Vol 18 (3) ◽  
pp. 68-73 ◽  
Author(s):  
A. M. Chernyavskiy ◽  
A. V. Fomichev ◽  
T. M. Ruzmatov ◽  
A. E. Medvedev ◽  
Yu. M. Prikhodko ◽  
...  
Keyword(s):  
Support Systems ◽  
Experimental Studies ◽  
Viscous Friction ◽  
Left Ventricular ◽  
Circulatory Support ◽  
Published Data ◽  
Technical Requirements ◽  
New Directions ◽  
Further Development ◽  
Mechanical Heart Support

The need of circulatory support systems in the treatment of chronic heart failure is increasing constantly, as 20% of the patients on the waiting list die every year. Despite the great need for mechanical heart support systems, the use of available systems is limited by its expensiveness. In addition, there is no one system that is 100% responsible to all medical and technical requirements and that would be completely safe for patient. Therefore, further research in the field of circulatory support systems considering health and technical requirements is relevant. One of the new directions in the study are disc pumps of viscous friction for liquid transporting, based on the Tesla pump principle. The operation principle of such pumps is based on the phenomenon of the boundary layer which is formed on the disk rotating in a fluid. There are experimental studies of models with different variants of the rotor suspension, various forms and numbers of the disks, forms of the pump housing. However, none of the above samples was brought to clinical trials. Furthermore, despite the potential of that model there have been no pumps of similar type used so far in circulatory support systems. Published data provide a basis for further development and testing of the pump model and allow hoping for leveling a number of significant shortcomings of modern left ventricular bypass systems. 

scholarly journals THE EXPERIMENTAL MODEL OF DISC-PUMP FOR MECHANICAL CIRCULATORY SUPPORT

2017 ◽  
Vol 18 (4) ◽  
pp. 93-101
Author(s):  
A. M. Chernyavskiy ◽  
T. M. Ruzmatov ◽  
A. V. Fomichev ◽  
A. E. Medvedev ◽  
Y. M. Prikhodko ◽  
...  
Keyword(s):  
Mechanical Circulatory Support ◽  
Support Systems ◽  
Current Model ◽  
Viscous Friction ◽  
Research Area ◽  
Circulatory Support ◽  
Technical Requirements ◽  
Further Development ◽  
Auxiliary Circulation ◽  
Mechanical Heart Support

The relevance of the use of circulatory support systems for the treatment of chronic heart failure (CHF) has increased over the recent years. Up to 20% of the patients from the waiting list for a donor heart die each year before they could get one. In our country, there is a huge need for mechanical heart support systems. However, the acquisition of foreign systems is associated with the excessive fi nancial costs. In addition, nowadays, there is no system that would meet all medical and technical requirements in full, and at the same time, would be of high safety for the patient. Therefore, research on the development of the systems of auxiliary circulation is highly relevant and is in demand in our country. One of the promising directions in this fi eld is disk pumps of viscous friction, which are based on the operation principle of Tesla disk pump. This article describes the creation and operation of the current model of the disk pump. The results of the bench tests confirmed that the expendable pressure characteristics of our disk pump are capable of providing the necessary parameters of blood circulation. The findings confi rm the perspective of the selected research area and provide the basis for further development and testing of this model of pump.

scholarly journals Experimental evaluation of mechanical heart support system based on viscous friction disc pump

2017 ◽  
Vol 19 (1) ◽  
pp. 28-34
Author(s):  
A. M. Chernyavskiy ◽  
T. M. Ruzmatov ◽  
A. V. Fomichev ◽  
A. E. Medvedev ◽  
Yu. M. Prikhodko ◽  
...  
Keyword(s):  
Experimental Evaluation ◽  
Experimental Studies ◽  
Peripheral Resistance ◽  
Circulatory System ◽  
Viscous Friction ◽  
Working Fluid ◽  
Pump Efficiency ◽  
Pump Design ◽  
Pump Performance ◽  
Mechanical Heart Support

Aim. Experimental evaluation of the viscous friction disk pump efficiency, studying the relationship between inter-disk clearance and sizes of input and output ports and pump performance parameters.Materials and methods. To assess the characteristics and to optimize the disk friction pump design the pump model and experimental stand were created. Pump dimensions were set on the basis of medical and biological requirements for mechanical heart support systems and with due consideration of the experimental studies of our colleagues from Pennsylvania. Flow volume of the working fluid was measured by float rotameter Krohne VA-40 with measurement error of not more than 1%. The pressure values in the hydrodynamic circuit were measured using a monitor manufactured by Biosoft-M. Expansion device allowed changing the flow resistance of the system simulating the total peripheral resistance of the circulatory system.Results. Linear direct correlation between the pump performance and the pressure drop of liquid being created at the inlet and outlet of the pump was obtained. The required flow rate (5–7 l/min) and pressure (90–100 mmHg) were reached when the rotor speed was in the range of 2500–3000 rev/min. It has been shown that the increase of the inlet diameter to 15 mm has not resulted in a significant increase in the pump performance, and that the highest efficiency values can be obtained for the magnitude of inter-disk gap of 0.4–0.5 mm.Conclusion. Designed and manufactured experimental disc pump model for pumping fluid has showed the fundamental possibility to use this model as a system for mechanical support of the heart.

The Tandem: Life System

2019 ◽  
pp. 138-144
Author(s):  
Danny Ramzy ◽  
Joshua Chung
Keyword(s):  
Left Ventricular ◽  
Circulatory Support ◽  
Published Data ◽  
Extra Corporeal Membrane Oxygenation ◽  
Membrane Oxygenator ◽  
System P ◽  
Ventricular Support ◽  
Insertion Techniques ◽  
Support Devices ◽  
Indications For Use

The Tandem Life series of support devices offers short-term mechanical circulatory support for patients with cardiopulmonary failure. The system provides options for left ventricular, right ventricular support, or both, as well as adaptation of a membrane oxygenator for extra corporeal membrane oxygenation (ECMO). This chapter outlines the indications for use, insertion techniques, and outcomes for the Tandem Heart, Tandem Lung, and Protek Duo platforms. Although limited published data exist for these technologies, experience is rapidly growing. The technology has allowed for patients to be fully ambulatory during time of support. The authors provide the perspective of one of the largest implanting centers internationally.

scholarly journals The Impact of Hemodynamic Reflex Compensation Following Myocardial Infarction on Subsequent Ventricular Remodeling

2019 ◽  
Vol 141 (9) ◽  
Author(s):  
Colleen M. Witzenburg ◽  
Jeffrey W. Holmes
Keyword(s):  
Myocardial Infarction ◽  
Ventricular Remodeling ◽  
Experimental Studies ◽  
Left Ventricular ◽  
Published Data ◽  
Compensatory Mechanisms ◽  
Compensatory Response ◽  
Wide Range ◽  
Reflex Compensation ◽  
The Impact

Patients who survive a myocardial infarction (MI) are at high risk for ventricular dilation and heart failure. While infarct size is an important determinant of post-MI remodeling, different patients with the same size infarct often display different levels of left ventricular (LV) dilation. The acute physiologic response to MI involves reflex compensation, whereby increases in heart rate (HR), arterial resistance, venoconstriction, and contractility of the surviving myocardium act to maintain mean arterial pressure (MAP). We hypothesized that variability in reflex compensation might underlie some of the reported variability in post-MI remodeling, a hypothesis that is difficult to test using experimental data alone because some reflex responses are difficult or impossible to measure directly. We, therefore, employed a computational model to estimate the balance of compensatory mechanisms from experimentally reported hemodynamic data. We found a strikingly wide range of compensatory reflex profiles in response to MI in dogs and verified that pharmacologic blockade of sympathetic and parasympathetic reflexes nearly abolished this variability. Then, using a previously published model of postinfarction remodeling, we showed that observed variability in compensation translated to variability in predicted LV dilation consistent with published data. Treatment with a vasodilator shifted the compensatory response away from arterial and venous vasoconstriction and toward increased HR and myocardial contractility. Importantly, this shift reduced predicted dilation, a prediction that matched prior experimental studies. Thus, postinfarction reflex compensation could represent both a source of individual variability in the extent of LV remodeling and a target for therapies aimed at reducing that remodeling.

Supraventricular tachycardia under mechanical circulatory support systems

2011 ◽  
Vol 59 (S 01) ◽  
Author(s):  
H Welp ◽  
V Kösek ◽  
G Mönnig ◽  
A Hoffmeier ◽  
A Rukosujew ◽  
...  
Keyword(s):  
Supraventricular Tachycardia ◽  
Mechanical Circulatory Support ◽  
Support Systems ◽  
Circulatory Support

Thoracoabdominalis aortakirekesztés során fellépő elektrofiziológiai változások a gerincvelőben

2020 ◽  
Vol 73 (4) ◽  
pp. 160-166
Author(s):  
Csaba Dzsinich ◽  
Péter Gloviczki ◽  
Gabriella Nagy ◽  
Klaudia Vivien Nagy
Keyword(s):  
Spinal Cord ◽  
Motor Evoked Potentials ◽  
Spinal Cord Ischemia ◽  
Experimental Studies ◽  
Neuron Specific Enolase ◽  
Neurological Complications ◽  
Neurologic Outcome ◽  
Published Data ◽  
Aortic Clamping ◽  
Sensory Evoked

Összefoglaló. A thoracoabdominalis aortakirekesztés okozta gerincvelő ischemia súlyos neurológiai következményeit számos klinikai és kísérleti tanulmány bizonyítja. E nehezen kiszámítható, súlyos szövődmény megelőzésének érdekében régi törekvés megfelelő intra- és posztoperatív monitorizálás kifejlesztése, ami előre jelzi a gerincvelő-funkció romlását, illetve a kialakuló celluláris károsodást. A legelterjedtebb, a klinikai gyakorlatban széles körben alkalmazott megoldás a gerincvelői kiváltott motoros potenciál (MEP) folyamatos ellenőrzése. Ritkábban alkalmazott – bár ígéretes – eljárás a biokémiai változások nyomon követése, ami a sejtszintű károsodás markereit használja fel az ischemia okozta változások felismerésére. Korábbi dolgozatunkban kutyákon végzett kísérleteink azon eredményeit ismertettük, amelyekben a 60 perces thoracoabdominalis aortakirekesztés okozta neurológiai változások és a perfúzió adatainak összefüggéseit tárgyaltuk. Jelen tanulmányunkban a gerincvelői motoros (MEP) és szenzoros (SEP) kiváltott potenciálok változásait vizsgáljuk a neurológiai végállapot vonatkozásában. Megállapítottuk, hogy SEP változásai a neurológiai károsodás mértékével értékelhető összefüggést nem mutatnak. A MEP-amplitúdó és -latencia értékei biztonsággal jelzik a fenyegető gerincvelő ischemiát. A neurológiai deficit mélységét (Tarlov 2,1,0) a MEP-értékek változásai numerikusan nem értékelhetően követik. Summary. Severe neurological complications of the thoracoabdominal aortic clamping were published in numerous clinical and experimental studies. These hardly predictable, devastating consequences demanded to develop a monitoring system which might detect impending level of spinal cord ischemia in time – in order to introduce or enhance protective procedures and prevent permanent neurological deficit. The most widely used monitoring in clinical practice is the continuous surveillance of the motor evoked potentials (MEP) during and after thoracoabdominal aortic clamping. Much less used, but promising opportunity is to control the metabolic changes and cellular integrity utilizing specific markers like liquor lactate and neuron specific enolase (NSE) etc. In our earlier study we published data of our canine experiment related to coherencies between neurological outcome and specific perfusion of the spinal cord during and after one hour thoracoabdominal aortic clamping. In the present paper we investigate the behavior of motor evoked (MEP) and sensory evoked (SEP) potentials related to neurological changes. We conclude the behavior of SEP values hardly correlate with the neurologic outcome, meanwhile decrease of MEP amplitude provides reliable signal for developing spinal cord ischemia. We could not confirm a numeric correlation of these data and the level of the final neurologic outcome.

Portable Life Support System: Current Status and Future Perspectives

2020 ◽  
Vol 14 (1) ◽  
pp. 12-28
Author(s):  
Jingang Jiang ◽  
Yihao Chen ◽  
Xuefeng Ma ◽  
Yongde Zhang ◽  
Zhiyuan Huang ◽  
...  
Keyword(s):  
Support System ◽  
Life Support ◽  
Support Systems ◽  
Vital Signs ◽  
Current Status ◽  
Life Support System ◽  
Life Support Systems ◽  
Special Circumstances ◽  
And Control ◽  
Further Development

Background: Portable life support system is used in the battlefield, disaster and in other special circumstances such as in space exploration, and underground survey to give the wounded a life support. The most dangerous period for the injured is the first hour after an injury, which is a crucial time for treatment. If the patient's vital signs were stabilized, more than 40% of the injured could be saved. The staff can efficiently complete the task if they get effective and stable vital signs during the operation. Therefore, in order to reduce the risk of disaster and battlefield mortality to improve operational safety and efficiency, it is necessary to study the portable life support system. Objective: The study aimed to provide an overview of recent portable life support system and its characteristics and design. Methods: This paper introduces the patents and products related to a portable life support system, and its characteristics and application. Results: This paper summarizes five kinds of portable life support systems which are box type, stretcher type, bed type, backpack type and mobile type. Moreover, the characteristics of different portable life support systems are analyzed. The paper expounds the problems of different types of portable life support systems and puts forward improvement methods to solve the problems. Finally, the paper points out the future development of the system. Conclusion: Portable life support system plays an increasingly important role in health care. In terms of the structure, function and control, further development and improvements are needed, along with the research on portable life support system.

Veno-arterial extracorporeal membrane oxygenation with concomitant Impella versus concomitant intra-aortic-balloon-pump for cardiogenic shock

Perfusion ◽  
2021 ◽  
pp. 026765912110339
Author(s):  
Shek-yin Au ◽  
Ka-man Fong ◽  
Chun-Fung Sunny Tsang ◽  
Ka-Chun Alan Chan ◽  
Chi Yuen Wong ◽  
...  
Keyword(s):  
Extracorporeal Membrane Oxygenation ◽  
Mechanical Circulatory Support ◽  
Primary Outcome ◽  
Left Ventricular ◽  
Circulatory Support ◽  
Queen Elizabeth Hospital ◽  
Intra Aortic Balloon Pump ◽  
Membrane Oxygenation ◽  
Significant Difference ◽  
Va Ecmo

Introduction: The intra-aortic balloon pump (IABP) and Impella are left ventricular unloading devices with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) in place and later serve as bridging therapy when VA-ECMO is terminated. We aimed to determine the potential differences in clinical outcomes and rate of complications between the two combinations of mechanical circulatory support. Methods: This was a retrospective, single institutional cohort study conducted in the intensive care unit (ICU) of Queen Elizabeth Hospital, Hong Kong. Inclusion criteria included all patients aged ⩾18 years, who had VA-ECMO support, and who had left ventricular unloading by either IABP or Impella between January 1, 2018 and October 31, 2020. Patients <18 years old, with central VA-ECMO, who did not require left ventricular unloading, or who underwent surgical venting procedures were excluded. The primary outcome was ECMO duration. Secondary outcomes included length of stay (LOS) in the ICU, hospital LOS, mortality, and complication rate. Results: Fifty-two patients with ECMO + IABP and 14 patients with ECMO + Impella were recruited. No statistically significant difference was observed in terms of ECMO duration (2.5 vs 4.6 days, p = 0.147), ICU LOS (7.7 vs 10.8 days, p = 0.367), and hospital LOS (14.8 vs 16.5 days, p = 0.556) between the two groups. No statistically significant difference was observed in the ECMO, ICU, and hospital mortalities between the two groups. Specific complications related to the ECMO and Impella combination were also noted. Conclusions: Impella was not shown to offer a statistically significant clinical benefit compared with IABP in conjunction with ECMO. Clinicians should be aware of the specific complications of using Impella.

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