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Huang Zhongping - - 2003
Recent research indicated that the dialysate flow distribution inside a hemodialyzer was not uniform ("channeling" of the dialysate flows). However, effect of the channeling on the solute clearance has not been directly and quantitatively examined. In this report, a novel experiment approach is presented to test the hypothesis that hollow ...
Gotch Frank A - - 2003
In vivo solute clearances can be estimated from dialyzer blood (Qb) and dialysate (Qd) flow rates and a solute- and dialyzer-specific overall permeability membrane area product (KoA). However, these calculations require knowledge of the flow rate of the effective solute distribution volume in the flowing bloodstream (Qe) in order to ...
Schneditz Daniel - - 2003
Low access blood flow is considered the most important cause of peripheral vascular access thrombosis, particularly with grafts. The measurement of access flow is time consuming, operator dependent, and may affect the efficiency of dialysis so that it cannot be done with every treatment. The measurement of recirculation, however, is ...
Weitzel William F - - 2003
Dialysis access monitoring may help decrease thrombosis-related morbidity. We investigated the effect of time elapsed since an access flow measurement on test accuracy of a novel flow monitoring method called variable flow (VF) Doppler. A retrospective review was conducted in 36 patients with prosthetic grafts for vascular access using access ...
Ronco C - - 2003
Continuous flow peritoneal dialysis (CFPD) is a therapy originally utilized in the sixties. It was then abandoned because of technical reasons, but, today, a new interest in this technique is emerging, because of new technical solutions and new hardware capabilities. CFPD is a peritoneal dialysis technique in which a certain ...
Passov Richard - - 2003
In late 2001, the directors of Pfizer asked that very question. And with good reason. After its 2000 merger with rival Warner-Lambert, the New York-based pharmaceutical giant found itself sitting on a net cash position of $8 billion, which seemed extraordinarily conservative for a company whose products generated $30 billion ...
Santoro Antonio - - 2003
The traditional control of the dialysis session comes about by means of an open-loop system. At the beginning of the session some parameters are set, such as the kind of dialyzer, the blood flow, the ultrafiltration rate, the dialysate conductivity and the dialysate temperature. Generally speaking, these parameters are not ...
Farjo Linda - - 2003
A discussion of complications related to the use of central venous catheters (CVCs), literature review, and a retrospective study were performed to see if blood collection from peripherally inserted central catheters (PICCs) in the treatment of oncology patients was a feasible option. The results were used to evaluate and update ...
Hoeben Heidi - - 2003
BACKGROUND/AIMS: Vascular access thrombosis is one of the most morbid problems encountered by hemodialysis patients. Surveillance protocols utilizing venous pressure (Vp) and vascular access blood flow (VABF) measurements have been employed to preserve vascular access. We undertook a study to evaluate combined dynamic Vp and VABF measurements in the identification ...
Pasko Deborah A - - 2003
In critically ill children weighing <10 kg, it is necessary to use blood as a priming solution for the extracorporeal continuous renal replacement therapy (CRRT) circuit before initiating CRRT to prevent hemodilution and maintain adequate oxygenation. However, blood bank blood usually contains supra-physiological electrolyte concentrations and a non-physiological acid-base balance ...
Ram Sunanda J - - 2003
BACKGROUND: The glucose pump test (GPT) is a recently introduced method of measuring hemodialysis access blood flow (Qa). A validation of GPT during dialysis has not yet been done, and performance characteristics of the method have not yet been fully analyzed. METHODS: The authors studied 33 patients (25 synthetic grafts, ...
Goldstein Lawrence J - - 2003
HYPOTHESIS: Under limited conditions, use of the radial artery (RA) for hemodialysis access in patients with end-stage renal disease is safe and effective. METHODS: The nondominant upper extremities of 211 consecutive patients with end-stage renal disease were evaluated with duplex ultrasonography to assess RA and ulnar artery (UA) flow contributions ...
Lamont Jeffrey P - - 2003
BACKGROUND: Vascular access devices placed into the central venous system are used routinely in the medical management of many patients. Catheter tip occlusion is a common complication of open-ended catheters, causing difficulty with blood withdrawal and infusion. This study evaluated whether a valved subcutaneous port system would have fewer associated ...
Tsuchiya Shinichiro - - 2003
A fully automated dialysis machine has been developed and evaluated clinically. It uses highly pure dialysate (produced by a new dialysate cleaning system) instead of the conventional physiologic saline for the processes of priming, guiding blood to the dialysis machine, replenishing fluid, and returning the blood to the body. The ...
Schwarz Christoph - - 2003
BACKGROUND: Measurement of access blood flow is the preferred noninvasive screening test for hemodialysis arteriovenous (AV) fistula stenosis. However, performance characteristics of the 2 most frequently used ultrasound techniques compared with fistulography remain elusive. METHODS: We evaluated 59 hemodialysis patients with native forearm AV fistulae who underwent all 3 measurements ...
Santoro Antonio - - 2003
Among the factors causing intradialytic haemodynamic instability, dialysate temperature has been shown to play a relevant role. An improved cardiovascular response during isolated ultrafiltration or with cooled dialysate has been described in the past. Cold dialysate may increase the external heat loss compensating for the increase in core temperature, thus ...
Poh Churn K - - 2003
We used an innovative, nonintrusive MRI technique called the two-dimensional (2D) Phase-Contrast (2DPC) velocity-imaging technique to investigate the effect of flow baffles on the dialysate-side flow distribution in two different hollow-fiber hemodialyzers (A and B); each with flow rates between 200 and 1000 mL/min (3.33 x 10(-6) and 1.67 x ...
Kaneda Hiroshi - - 2003
BACKGROUND: When access cannot be achieved using a native arteriovenous fistula or a synthetic prosthetic graft, central venous catheters are usually placed. This mode of access is short-lived, prone to infection, stenosis and thrombosis of central veins. To overcome access problems, we developed a new native vascular access ('femoral vein ...
Lin Julian - - 2003
The treatment of hydrocephalus with shunt insertion is fraught with high failure rates. Evidence indicates that the proximal holes in a catheter are the primary sites of blockage. The authors have studied ventricular catheter designs by using computational fluid dynamics (CFD), two-dimensional water table experiments, and a three-dimensional (3D) automated ...
Barcelona Sandra L - - 2003
Cases involving massive blood transfusion may require the use of specialized blood warmers, such as the Level 1 (L-1) (Level 1 Technologies, Inc., Rockland, MA) or the Rapid Infusion System (RIS) (Haemonetics Corp., Braintree, MA). In this in vitro study, we compared the infusion and warming capabilities of the L-1 ...
Degim Ismail Tuncer - - 2003
Monitoring of the urea level of patients with insufficient kidney function requires repetitive blood sampling. The potentially painful nature of blood sampling and the difficulty of venous access, particularly in premature neonates, as well as possible complications of needle injuries, create many disadvantages. A non-invasive technique needs to be developed ...
Kesziová A - - 2003
In order to deliver a specific dialysis dose (Kt/V) to all patients, their product Kt (urea clearance K multiplied by dialysis time t) should be individually adjusted according to total body water (V) of each patient. With dialysis time being fixed in most centres for organisational reasons, such individualization can ...
Krivitski Nikolai M - - 2003
The introduction of routine access flow measurement methodology has enabled accurate identification of problematic accesses and provided a means for follow-up evaluation. These methods have uncovered, in some cases, that interventions are either immediately unsuccessful or that they fail within 3 months to maintain flow above preintervention levels. The purpose ...
Freida Philippe - - 2003
BACKGROUND: Growing concern over the limited capacity of the peritoneal dialysis (PD) system has revived interest in continuous flow peritoneal dialysis (CFPD), a modality in which continuous circulation of PD fluid is maintained at a high flow rate using two separate catheters or one dual-lumen catheter. The CFPD regimen contrasts ...
Poh Churn K - - 2003
Blood side and dialysate side flow distributions play an important role in determining the optimal use of dialysis membrane in hemodialyzers for the removal of uremic solutes. In this article, we used two nonintrusive magnetic resonance imaging (MRI) techniques called the two-dimensional phase contrast (2DPC) and two-dimensional Fourier transform (2DFT) ...
Liepsch D - - 2003
Arteriovenous fistulae (AVF) are commonly used in dialysis treatment of uremic patients. However, many AVF create problems and have to be re-examined. Problems arise in the cannulation site and must be treated with antibiotics, and stenosis, both in the arterial and in the venous side of the AVF. In the ...
Goldfarb-Rumyantzev Alexander - - 2003
The impact of clinical and other variables on single-pool Kt/V (spKt/V) is unclear. The goal of this study was to identify clinical and hemodialysis treatment related predictors of spKt/V and use multilinear regression (LM), tree-based modeling (TBM), and artificial neural networks (ANN) to predict actual spKt/V. When 602 hemodialysis records ...
Patzer John F JF - - 2003
We used the thermodynamic principles governing bound solute dialysis, commonly referred to as "albumin dialysis" or "sorbent dialysis" and practiced clinically with the Molecular Adsorbent Recirculating System (MARS) and Biologic-DT approaches, respectively, to develop a comprehensive understanding of the process. Dimensionless parameters emerging from the thermodynamic analysis that govern bound ...
O'Mara Neeta B - - 2003
BACKGROUND: Low blood flow is a frequent complication of central-vein (CV) dialysis catheters. Since thrombotic occlusion accounts for many cases of reduced blood flow, it is common practice to administer empiric thrombolytic therapy in an attempt to restore catheter patency and improve function. METHODS: We prepared tissue plasminogen activator (tPA) ...
Twardowski Zbylut J - - 2003
Chronic hemodialysis sessions, as developed in Seattle in the 1960s, were long procedures with minimal intra- and interdialytic symptoms. Financial and logistical pressures related to the overwhelming number of patients requiring hemodialysis created an incentive to shorten dialysis time to four, three, and even two hours per session in a ...
Sallam Hassan N - - 2003
To investigate the impact of technical difficulties, choice of catheter, and the presence of blood during embryo transfer on the results of in vitro fertilization and ICSI. A cohort of 784 consecutive cycles in 655 in vitro fertilization and ICSI patients were studied. Negotiating the cervix, using the volsellum, presence ...
Dhondt Annemieke W - - 2003
BACKGROUND: The Genius single-pass batch system for hemodialysis contains a closed reservoir and dialysate circuit of 75 L dialysate. The unused dialysate is withdrawn at the top of the reservoir and the spent fluid is reintroduced into the container at the bottom. Although it has been claimed that both fractions ...
Leblanc M - - 2003
Abstract: Native arterio-venous fistulas (AVFs) are preferred for hemodialysis vascular access over synthetic grafts and long-term catheters. However, prevalence rates of native AVFs are variable around the world and have increased only slightly in United States since the DOQI guidelines. To increase rates of native AVFs, pre-operative vascular mapping by ...
Tordoir Jan H M - - 2003
INTRODUCTION: Radiocephalic wrist arteriovenous fistulae (RCAVF) are the primary and best option for vascular access for haemodialysis treatment. However, 10-24% of these AVFs fail due directly to thrombosis and non-maturation. In a prospective study, the failure modes of radiocephalic AVFs and the impact of surgical and interventional treatment on fistula ...
Gutzwiller J P - - 2003
BACKGROUND: Hyperphosphatemia and hyperkalemia are major determinants of morbidity and mortality in hemodialysis patients. Half of the dialysis population suffers from hyperphosphatemia which is now recognized as an important cardiovascular disease risk factor. It is, therefore, necessary to improve the removal of these molecules. In this study, we investigated the ...
Bambi Franco - - 2003
BACKGROUND: Leukapheresis procedures require adequate flow rates, which in children may frequently involve invasive vascular access placement. STUDY DESIGN AND METHODS: A minimally invasive peripheral radial artery catheter was used for drawing blood in 85 leukapheresis procedures performed in 33 pediatric patients. Blood return to the patients was provided by ...
Farkas Agnes - - 2003
The lacrimal urea content was found to be proportional to that of blood, which suggested its possible utilization in the monitoring of hemodialysis as a less invasive method. On the other hand, however, arginase activity was detected in tears, which may influence the urea content independently of blood urea concentration. ...
Gastaldon F - - 2003
The main target for low flux hemodialyzers is an efficient low molecular weight solutes clearance. Such efficiency is largely dependent on the optimization of diffusion between blood and dialysis solution. The diffusion process can be impaired if there is a mismatch between blood and dialysate flow distribution in the dialyzer. ...
Coté Charles J - - 2003
Retractable needle IV catheters are designed to reduce needle-stick injuries; their use is mandated by federal regulations. We undertook a prospective data collection with the "traditional" IV catheters (JELCO) versus the "new" (Angiocath Autoguard). Assignment of catheter type was randomized by week. Data collected included assessment of the difficulty of ...
Mandolfo S - - 2003
Optimization of hemodialysis treatment parameters and the characteristics of the dialyzer are crucial for short- and long-term outcome of end stage renal disease patients. The new high-flux membrane Helixone in the dialyzer of the FX series (Fresenius Medical Care, Germany) has interesting features, such as the relationship of membrane thickness ...
Aschwanden Markus - - 2003
Dialysis access-associated steal syndrome (DASS) is an uncommon but serious complication after the creation of an arteriovenous shunt for hemodialysis and is related to an excess perfusion of the fistula. Several surgical options have been described for DASS correction. To achieve an adequate distribution of the blood flow towards the ...
Sakai Yoshitada - - 2003
It is very important to observe the concentrations and flow patterns of blood through a dialyzer to evaluate its function and to obtain the most appropriate design. We established a visualization method for the blood flow pattern in a dialyzer using X-ray computed tomography, and investigated the so-called internal filtration ...
Zacharias James M - - 2003
BACKGROUND: The use of central venous catheters as a source of vascular access in patients undergoing hemodialysis may be complicated by thrombosis. Frequently, thrombolytics are used in an attempt to reestablish blood flow through partially or completely occluded catheters. OBJECTIVE: To compare the efficacy of alteplase (recombinant tissue plasminogen activator) ...
Magnasco Alberto - - 2002
BACKGROUND: A good test for monitoring blood flow (Q(a)) must be accurate, rapid and economical in order to allow frequent easy measurements. The glucose pump test (GPT) is based on a constant glucose infusion as a dilutional indicator of Q(a). METHODS: GPT protocol requires a constant glucose infusion, by a ...
Uchino Shigehiko - - 2002
To test the hypothesis that dialysis using a new large pore membrane would achieve effective cytokine removal, blood from six volunteers was incubated with endotoxin (1 mg) and then circulated through a closed circuit with a polyamide membrane (nominal cut-off: 100 kDa). Hemodialysis was conducted at 1 or 9 L/hr ...
Dell'Aquila Roberto - - 2002
In the last few years, automated peritoneal dialysis (APD) has undergone considerable improvements due to technological developments. The definition of a minimal dose of peritoneal dialysis (PD) has not yet been completely assessed. Appropriate use of APD requires an evaluation of dialytic efficiency in terms of dialytic indexes and their ...
Stigant Caroline E - - 2002
PURPOSE OF REVIEW: This review examines recent developments in the understanding of the effect of conventional, bioincompatible peritoneal dialysis fluids on structural and functional changes in the peritoneal membrane. Emphasis is placed on the clinically relevant outcome of failure of long-term peritoneal dialysis. Therapeutic strategies to prevent technique failure, including ...
Tan Han Khim - - 2002
OBJECTIVES: To measure outflow and inflow hydraulic resistance in double-lumen catheters used for hemofiltration under standardized laboratory conditions. SETTING: ICU Laboratory of tertiary unit. METHODS: Heparinized spent red cells diluted in polygeline solution to a constant hematocrit of 32% at 37 degrees C were pumped using a standard Prisma M60 ...
Mueller Xavier M - - 2002
BACKGROUND: During percutaneous cannulation, the diameter of the venous cannula is determined by the size of the access site. To limit this restriction, the Smart cannula (Cardiosmart Ltd., Fribourg, Switzerland) has been developed. Because its design allows self-expansion within the recipient vein, diameter restriction is limited to the access site. ...
Robbin Michelle L - - 2002
PURPOSE: To compare various objective ultrasonographic (US) criteria for native arteriovenous fistula (AVF) maturation with subsequent fistula outcomes and clinical evaluation by experienced dialysis nurses. MATERIALS AND METHODS: US fistula evaluation results were analyzed retrospectively in 69 patients within 4 months after AVF placement; adequacy for dialysis was known in ...
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