Centrifugal blood pumps are used widely for cardiopulmonary bypass, as ventricular assist devices, and for extracorporeal membrane oxygenation (ECMO). However, there is no centrifugal blood pump that is suitable for long-term ECMO. The authors developed the Gyro C1E3 centrifugal blood pump (Kyocera Corporation, Kyoto, Japan), which has superior antithrombogenic, antitraumatic, ...

To avoid using sensors with low biocompatibility and low durability in implantable total artificial heart (TAH) systems, the authors previously proposed a new method for estimating instantaneous values of flow rate and pressure head on the basis of voltage, current, and rotational speed in a motor driven centrifugal pump. The ...

This paper reports the impact of four sequential maturation pond interventions on the removal of thermotolerant "faecal" coliform bacteria at a full scale WSP system in tropical Colombia. Each intervention was designed to increase hydraulic retention time and was followed by continuous physico-chemical logging and meteorological monitoring, and simultaneous tracer ...

The prototype of the miniature vibrating flow pump (VFP) is developed for the external shunt catheter. The cross-slider mechanism is applied to vibrate the tube, which causes the pumping effect. This mechanism results in successful development of the miniature and lightweight VFP. By the use of the prototype VFP, the ...

BACKGROUND AND OBJECTIVES: Portable patient-controlled pumps used for perineural local anesthetic infusion appear to be gaining acceptance and are used for an increasing number of medically unsupervised ambulatory patients. The infusion rate accuracy and reliability of these pumps, which allow patient-controlled boluses of potentially toxic medication, has not been independently ...

The development of a novel, fully integrated, miniaturized pumping system for generation of pressure-driven flow in microfluidic platforms is described. The micropump, based on electroosmotic pumping principles, has a multiple open-channel configuration consisting of hundreds of parallel, small-diameter microchannels. Specifically, pumps with microchannels of 1-6 microm in depth, 4-50 mm ...

The increased demands placed on solution propulsion by programmed flow systems, such as sequential injection analysis, lab-on-value technology, bead injection and multi-commutation, has highlighted the inability of many conventional pumps to generate a smooth, consistent flow. A number of researchers have examined ways to overcome the inadvertent, uncontrolled pulsation caused ...

We have developed an in vitro method for creating pulsatile flows to mimic coronary type flow patterns on a beat-to-beat basis. The flow is created by accelerating fluid loops about an axis, inducing relative wall motion. Using this technique, a variety of oscillating flow patterns can be generated and modulated. ...

The Gyro permanently implantable pump consists of a sealless pump housing and an impeller supported with a double pivot bearing. The secondary vanes are attached to increase the secondary flow to avoid thrombus formation behind the impeller. Flow visualization studies using an oil film method were performed on three types ...

PURPOSE: To evaluate the performance of the Panomat P-10 micro-volumetric infusion pump for its use in drug administration at minimal flow rates (microL x hr(-1); e.g., intrathecal application). METHODS: Fluid delivery at steady state conditions, and after vertical displacement of the syringe pump by -50 cm was determined gravimetrically. The ...

Pulmonary waveform generators consisting of motor-driven piston pumps are frequently used to test respiratory-function equipment such as spirometers and peak expiratory flow (PEF) meters. Gas compression within these generators can produce significant distortion of the output flow-time profile. A nonlinear model of the generator was developed along with a method ...

A novel inexpensive 0.6 MPa (84 psi) flow system based on a low-cost diaphragm pump has been developed. The unfavourable strong pulsation of the pump has been overcome by using highly flexible silicone tubing as a pulse suppression coil. This results in a smooth pulse-free continuous flow of 100 mL ...

Coil-type silicone membrane oxygenators can only be used with roller blood pumps due to the resistance from the high blood flow. Therefore, during extracorporeal membrane oxygenation (ECMO) treatment, the combination of a roller pump and an oxygenator with a high blood flow resistance will induce severe hemolysis, which is a ...

A coaxial atrial cannula connected to a mini-centrifugal pump was developed to bypass the right heart during extreme exposures in off-pump coronary artery bypass surgery. This study was designed to test the effect of this pump, running during 24 hours, on blood elements to evaluate its use as a prolonged ...

OBJECTIVE: We developed "EVAHEART": a compact centrifugal blood pump system as an implantable left ventricular assist device for long-term circulatory support. The 55 x 64 mm pump is made from pure titanium, and weighs 370 g. The entire blood-contacting surface is covered with an anti-thrombogenic coating of diamond like carbon ...

Experimental studies on the effects of scaling on the performance of centrifugal blood pumps were conducted in a closed-loop test rig. For the prototype, eight different impellers of the same outer diameter of 25 mm were tested at 1,500, 2,000, and 2,500 revolutions per minute (rpm) using blood analog as ...

During the past 10 years, different types of blood pumps were developed to address various clinical needs. The Nikkiso centrifugal blood pump was developed for cardiopulmonary bypass application. This blood pump has been widely used in Japan in more than 20% of the cardiopulmonary bypass procedures. The Kyocera C1E3 Gryo ...

Considering a miniaturization of percutaneous cardiopulmonary support (PCPS) system, we have developed a pump system that can estimate flow rate and pressure head in the circuit. A commercially available centrifugal blood pump (C1E3, Kyocera Co., Ltd., Kyoto, Japan) with an exclusive motor driver was used in the experiment. In this ...

An overview from an evolutionary perspective is presented on the research of the past 2 decades on insect circulatory organs. Based on various functional morphology it is clear that the flow mode of the dorsal vessel ('heart') has changed during the evolution of hexapods. In all apterygotes and mayflies the ...

Fluid dynamic forces in centrifugal blood pump impellers are of key importance in destruction of red blood cells (RBCs) because high rotational speed leads to strong interaction between the impeller and the RBCs. In this paper, three-dimensional models of five different blade geometries are investigated numerically using the commercial software ...

A new venous bag has been developed, prototyped, and tested. The new bag has its inlet, outlet purge, and infusion tubes extending upward from the top of the bag, and are threaded through, bonded to, and sealed within a flat rigid top plate. This design allows the bag to be ...

For long-term application, rotary pumps have to solve the problems of bearing wear and thrombosis along the bearing. Some investigators choose the magnetic bearing for zero friction and to provide no contact between the rotor and stator; the former avoids the mechanical wear and the latter eliminates the possibility of ...

This paper presents the velocity measurements in the gap between the impeller and the pump casing of a 5:1 enlarged centrifugal blood pump model at operating condition. Both the radial and tangential velocity at the gap were measured. It was found that there was no cross flow in both the ...

Rotary ventricular assist devices (VADs) are primarily used during surgery and short-term postoperative assistance. There are issues involving the use of rotary VADs including the behavior of flow emanating from the assist device which might induce flow irregularities that could potentially lead to stroke or cerebrovascular accident. An in vitro ...

Electro-mechanical equipment for multiple blood withdrawal from small experimental animals applied to a centrifuge with maximal 6g gravitational overloading has been developed and tested. The equipment consists of a transmitter and receiver equipped by microcomputers. Active rotor stepping motors are driving four pairs of syringes. It is also possible to ...

Rotary blood pumps as a left ventricular assist device have several advantages over the use of existing pulsatile devices used for this purpose. The relative velocity distribution to the rotating impeller was observed by high-speed videography and particle image velocimetry (PIV) with the purpose of characterizing the unsteady fluid motion ...

We investigated the hydrodynamic flows around tablets during several pharmacopeial dissolution tests: the rotating basket (RB), paddle (PD), flow-through cell (FT), and disintegration (DI) tests. The determination of hydrodynamic flow was based on the dissolution rate of United States Pharmacopeial salicylic acid nondisintegrating calibrators, and showed that, compared with the ...

This article presents computational studies on the effects of inlet guide vanes (IGVs) on the flow pattern and shear stress in a centrifugal blood pump. The effect of IGVs is to introduce a pre-swirl to fluid particles entering the impeller with the intention that the fluid particles will travel along ...

Vacuum-assisted venous drainage (VAVD) is frequently used to increase venous return through smaller venous cannula and reduced venous line size. The purpose of this study is to determine the maximal flow rates achieved through various venous cannula with varying amounts of negative pressure applied during VAVD. The first test circuit ...

The separation of wide molecular mass (Mr) ranges of macromolecules using frit inlet asymmetrical flow field-flow fractionation (FI-AFlFFF) has been improved by implementing a combination of field and flow programming. In this first implementation, field strength (governed by the cross flow-rate through the membrane-covered accumulation wall) is decreased with time ...

A short review of the principles of near infrared reflectance spectroscopy (NIRS) in whole blood is followed by a discussion on the influence of hemolysis. The increase of free plasmahemoglobin (PHb) has a strong influence on the continuous measurement of hematocrit and oxygen saturation (O(2)S) by NIRS. In view of ...

A newly conceived blood pump for pulsatile cardiopulmonary bypass (CPB) is presented. The new device's main design features (fully disposable pumping head with ring shaped valves) were intended to overcome the factors that today limit the use of pulsatile blood pumps, i.e., the complexity and costs of devices. The pump ...

A dynamic model was developed for a Hemopump that withdraws blood from the left ventricle and discharges it to the aorta through a miniature axial-flow pump. Incorporation of the Hemopump model in a previously established model for the canine circulatory system enabled the effects of the Hemopump on various haemodynamic ...

Numerical modeling techniques were used to simulate stream-aquifer interactions from seasonal ground water pumping. We used stream-aquifer models in which a shallow stream penetrates the top of an aquifer that discharges ground water to the stream as base flow. Because of the pumping, the volume of base flow discharged to ...

Because of the risk of vein collapse, the benefits of using a centrifugal pump to assist venous drainage for cardiopulmonary bypass are limited when the tips of peripheral cannulas are maintained within the vena cava. Using a mock circuit including 20 mm diameter latex tubing to mimic a vena cava, ...

In centrifugal blood pumps, blood is moved into a circular path with the help of an impeller. In a nutating pump, the nutating body takes over the role of the impeller. Since the nutating body itself does not rotate, this pump needs no seal, no blood contacting, and no magnetic ...

Since 1980s, the author's impeller pump has successively achieved the device implantability, blood compatibility and flow pulsatility. In order to realize a performance durability, the author has concentrated in past years on solving the bearing problems of the impeller pump. Recent progress has been obtained in developing durable and permanent ...

To investigate the powder plug formation process of silicified microcrystalline cellulose (SMCC) under compression forces consistent with automatic capsule-filling machines, a single-ended saw-tooth wave was used to make powder plugs with different heights (6, 8, 12 mm), at two different punch speeds (1 and 50 mm/s) on a tablet compaction ...

Separation efficiency and scalability of Pall Corporation's new Mustang stacked membrane chromatographic devices were investigated, using both the 10-ml and l(-1) models and comparing the responses of tracer pulses obtained for conventional and reverse-flow operation. Tracers included AMP, lysozyme, and thyroglobulin, which vary in relative molecular mass from less than ...

In response to the European Union Urban Waste Water Directive, primary and secondary treatment is being installed at Birkenhead Treatment Works on the Wirral Peninsula in the North West of England. The 3.26 m diameter, 3.5 km long Great Culvert conduit currently conveys both river and sewage flow, and discharges ...

Monitoring systems for measuring rainfall, as well as flow rates and pollutant quantities conveyed by sewers and/or discharged by stormwater overflow devices, have become a common feature in many municipal sewer services, in part spurred by recent regulatory requirements. However, the state of measurement conditions in sewer facilities does not ...

The aim of this study was to develop spheronized microparticulates as a drug delivery system using the 1-step closed rotor disk fluid-bed technology, and to scale up the batch spheronization process. Ibuprofen was used as the model drug and microcrystalline cellulose/sodium carboxymethyl cellulose hydrocolloid (Avicel(R) RC-581 or CL-611) was present ...

A new in vitro flow system was developed to investigate the impact of laminar flow on extracellular matrix formation and tissue development. The dynamic in vitro system was designed to provide a cross flow arrangement of main flow induced by a dialysis roller pump (500 ml/min), and nutrition flow by ...

Fluid flow at the microscale exhibits unique phenomena that can be leveraged to fabricate devices and components capable of performing functions useful for biological studies. The physics of importance to microfluidics are reviewed. Common methods of fabricating microfluidic devices and systems are described. Components, including valves, mixers, and pumps, capable ...

To reduce the possible thrombogenicity of the pump studied, pump characteristics and washout conditions were compared between a pump with a semi-open and a pump with a full-open impeller. A difference in hydrodynamic performance was observed between the semi-open impeller and the full-open impeller; the pressure in the former was ...

Summary: Object. For patients with cerebral embolism, we are using an extracorporeal pump to rev ascularize the more peripheral brain tissues far from the thrombus, proceeding the microcatheter beyond the thrombus, and dissolving the thrombus during a satisfactory time as required. Methods. As the critical cerebral blood flow is thought ...

A fully computer-controlled manifold is described which enables the automatic dilution and measurement of solutions which are too concentrated to be measured by direct aspiration in FAAS. The sample solution is propelled by a peristaltic pump equipped with two pump tubes of different diameters, the difference between the nebulizer uptake ...

OBJECTIVE: In this study a comparison of the vascular reactivity in the coronary circulation was investigated by injection of acetylcholine (ACh) and adenosine (ADO) in coronary bypass patients, operated on with or without the assistance of heart-lung machine. The patients operated on with heart-lung machine were further divided into subjects ...

Neonatal and pediatric extracorporeal membrane oxygenation (ECMO) is carried out commonly using occlusive blood pumps. Centrifugal pumps provide simple and safe technology for transportation on ECMO. The assistence respiratoire extra corporelle (AREC) system enables single needle venovenous ECMO for infants. We report on our experience with neonatal and pediatric ECMO ...

Although biosensors are by means suitable for continuous biomedical monitoring, due to fouling and blood clotting, in vivo performance is far from optimal. For this reason, ultrafiltration, microdialysis or open tubular flow is frequently used as interface. To secure quantitative recoveries of the analyte of interest, sampling at submicrolitre level ...