bluuebunny/crossref_metadata_2025 huggingface dataset:
Long‐Term ExPerience with the Technique of Subclavian and Femoral Vein Cannulation in Hemodialysis
Authors: Erben Josef , Kvasnička Jiří , BaŠhecký Jan , Groh Jindřich , Zahradník JiřiA , Rozsíval Vladimír , BaŠtecká DráŽa , Fixa Pavel , Kozák Josef , Herout Vladimíh
Published: July 2010

Large vein cannulation for hemodialysis was used in 1164 patients undergoing dialysis treatment and in an acute dialysis program. Subclavian vein cannulation was utilized in 2494 dialyses, and femoral vein cannulation was used in 2368 dialyses. No significant differences with regard to clinical complications were encountered in either type of cannulation. The mortality rate due to subclavian vein cannulation was 0.12%, while that due to femoral vein cannulation was 0.04%. The main risk of subclavian vein cannulation was arterial bleeding, due to trauma to an artery, and pneumothorax, more likely occurring in asthenic patients or in patients with emphysema. Single‐needle hemodialysis using subclavian or femoral vein cannulation gave the same results as the arteriovenous Cimino fistula. Intermittent or combined use of both types of large vein cannulation is advantageous in long‐term regular dialysis patients that are waiting for a new fistula.
Mass Transfer Characteristics of Hollow‐Fiber Dialyzers and Hemoperfusion Devices
Authors: Cooney David O. , Daly John S.
Published: July 2010

Clearance versus time tests were carried out on three charcoal‐based hemoperfusion devices (Sandev, Becton‐Dickinson and Gambro) using solutions of 1 gm/L sodium salicylate in a pH 7.4 buffer and in bovine blood at flow rates of 200 rnl/min. Similar tests were performed on a Cordis Dow 2.5 m2 hollow‐fiber dialyzer at a tube side flow rate (Qb) of 200 ml/min. Buffer was pumped through the dialysate side at a flow rate (Qd) of 400 ml/min. Two dialyzers were run in series at Qb= 200 ml/min and Qd = 500 or 1000 ml/min. Mass transfer resistances were computed from the test results. These values are useful in that they constitute an index of the intrinsic initial kinetics of solute transfer in each device. However, the clearance versus time curves indicate that these initial kinetics decrease at different rates for each hemoperfusion unit as sorption capacity begins to be depleted. In contrast, the initial clearances for the dialyzers remain at their initial values. These data reveal much about the relative mass transfer characteristics of these devices.
Counterregulatory System in an Artificial Endocrine Pancreas Glucose Infusion Algorithm
Authors: Yamasaki Yoshimitsu , Shichiri Motoaki , Kawamori Ryuzo , Goriya Yoshikazu , Sasai Tomonori , Morishima Toyohiko , Nomura Makoto , Tohdo Ryohei , Abe Hiroshi
Published: July 2010

An artificial endocrine pancreas has been developed by adding a glucose infusion system to the artificial beta cell system. In this computer algorithm, glucose is infused on the basis of proportional and derivative actions to blood glucose concentration with the time delay constant between blood withdrawal and initiation of glucose infusion.

When glucose was infused on the basis of proportional action with a 20‐minute time delay, the prompt restoration to normoglycemia from the hypoglycemic state with a smaller amount of glucose was shown in depancreatized dogs.

These results indicate that the artificial endocrine pancreas thus prepared is not only a useful device to safely control blood glucose, but also is an efficient research tool for the analysis of the blood glucose regulatory mechanism.
Capabilities of the Redyo Cartridge for Regeneration of Hernofiltrate
Authors: Fuchs C. , Dorn D. , Rieger J. , van Doorn A. W. J. , Striebel J. P. , Scheler F.
Published: July 2010

Capabilities of the Redy® cartridge for hemofiltrate regeneration were tested. Electrolytes, creatinine, BUN, uric acid, acid‐base, glucose, heparin, fluoride and amino acids were measured in the cartridge inflow and outflow (V = 70 ml/min) over a four‐hour period. There was complete adsorption of potassium, calcium, magnesium, creatinine, BUN, uric acid, phosphate and heparin. Sodium ions, hydrogen ions, fluoride ions and possibly other trace elements are released by the cartridge. Amino acid absorption is almost complete if the amino acids are aromatic, have two or more N‐atoms or if they have S‐atoms. When using hemofiltrate after sorbent regeneration for reinfusion to the patient, one has to consider electrolyte substitution (i.e., K, Ca, Mg), sodium balance, trace element metabolism, acid‐base problems, amino‐acid profiles and ammonia overload.
Problems of Competition in Charcoal Hemoperfusion for the Treatment of Intoxications
Authors: Gundermann Karl‐Josef , Lie Tschong Su
Published: July 2010

Both toxic and physiological substances are adsorbed during an extracorporeal hemoperfusion for the treatment of exogenous and endogenous intoxications. Using a closed circuit in uitro, we perfused one liter saline or fresh human plasma with 4425 μmol creatinine, 4854 μmol and 97,086 μmol barbital‐Na, 597 μmol bromthalein, 1942 μmol and 29,126 pmol raffinose, and 200 μmol inulin in different combinations over 70 gm of uncoated charcoal with the following results: 1. The adsorptive capacity of other substances is not influenced by preadsorption of the charcoal with a low or middle molecular weight substance; 2. In the low and middle molecular weight range, there is no competition between two substances in a solution; 3. The simultaneous usage of two substances of middle and high molecular weight, or preadsorption with a high molecular weight substance, reduces the rate of adsorption and the capacity of charcoal for middle molecular weight substances, but not for low molecular weight substances.
High‐Permeability Membrane Hemodialysis and Hernofiltration in Acute Hepatic Coma: Experimental and Clinical Results
Authors: Opolon Pierre
Published: July 2010

A high‐permeability polyacrylonitrile membrane was used for hemodialysis in experimental animals with induced liver ischemia and for acute treatment of 39 patients with fulminant hepatic failure. Measurements were made of amino acids and other relevant compounds; nine patients survived. In long‐term studies, the polyacrylonitrile membrane was used for hemofiltration in ten clinical cases of fulminant hepatic failure and coma. Five patients, including two pregnant women, survived.
Artificial Organs: Thoughts & Progress:Plasma β‐Endorphin Levels In Chronic Schizophrenic Patients and Normal Controls
Authors: Espinosa‐Meléndez Enrique , Lal Samarthju , Nair N. P. Vasavan , Chang Thomas Ming Swi
Published: July 2010

Plasma β‐endorphin was measured in 35 chronic schizophrenic patients (15.47 ± 15.39 pmol/L) and 3 normal volunteers (19.55 ± 11.23 pmol/L). There was no significant difference between the levels of the two groups.
Artificial Cells: The Use of Hybrid Systems
Authors: Chang Thomas Ming Swi
Published: July 2010

Artificial cells consist of a hybrid system combining biological and synthetic materials. It has been investigated for enzyme therapy, erythrocyte substitution, hemoperfussion, artificial kidney, artificial liver, detoxification, immunoadsorbents and other applications.
Influence of Concentration Polarization in Post‐Dilutional Hernofiltration of Human Plasma
Authors: Calderaro V. , Memoli B. , Andreucci V.E. , Drioli E. , Albanese O.
Published: July 2010

In this paper experimental results relative to human plasma ultrafiltration by means of artificial flat sheet membranes (RP‐6 hemofilters, from RhBne Poulenc) are discussed. The selectivity of the membranes toward radio‐labelled chemical species with various molecular weights (280–60,000) during the plasma ultrafiltration has been determined.

Significant changes in membrane rejection, particularly for species with lower MW, have been observed that are attributed to concentration polarization effects. These phenomena may explain clinical observations.
Flow Characteristics of the St. Jude Prosthetic Valve: An In Vitro and In Vivo Study
Authors: Yoganathan Ajit P. , Chaux Aurelio , Gray Richard J. , De Robertis Michele , Matloff Jack M.
Published: July 2010

The St. Jude cardiac prosthetic aortic valve was evaluated in vitro and in vivo in an attempt to establish flow characteristics and to correlate them with clinical findings. In vitro, a fluid vehicle (6% Polyol V‐10, 32°C) with viscosity similar to blood (0.035 dyne‐sec/cm2) was used under conditions of steady flow through a flow chamber simulating the aortic root. Gradient, velocity, and shear stress were measured 5.79 mm, 26.79 mm, 44.79 mm, and 77.79 mm downstream from 25‐mm and 27‐mm valves using a laser‐Doppler anemometer. At 417 ml/sec, the valve gradient was 6.2 mmHg with the 25‐mm valve, and 5.2 mmHg with the 27‐mm prosthesis. Velocity was maximum at the orifice center, and wall shear stress was low (maximum 600 dyne/cm2).

In vivo, six patients with 25‐mm St. Jude aortic valves were studied within 48 hours after surgery to determine cardiac output, valve flow, and gradient. The gradient was 3.3 ± 1.9 mmHg (M ± SD) at 249 ± 96 ml/sec and the effective valve area was as large as the geometric area (2.58 vs. 3.09 cm2).

Thus, flow through the St. Jude valve is unobstructed and central, has low turbulence, and achieves optimal effective valve area for a given available orifice area.
Experimental and Clinical Ventricular Bypass During Acute Heart Failure
Authors: Lokshin Leonid S. , Osipov Valentin P. , Knjazeva Galina , Rogov Konstantin A. , Lepilin Mikhail G. , Arseniev Sergei B. , Romanov Vladimir A. , Leonova Svetlana A.
Published: July 2010

Mechanical support of the failing heart in the form of bypass of the left and right ventricles by roller pumps was used in 25 dogs with model cardiogenic shock. Early application of left ventricular bypass in acute heart failure normalizes the myocardial bioenergy state and promotes reversible changes in myocardial infrastructure as demonstrated by an increased surface area of mitochondrial cristae. On the basis of hemodynamics and morphology, we conclude that pump‐aided bypass of ventricles without synchronization is a simple and effective method of circulation assistance.

Mechanical support duration from 1 to 138 hours has been used in 10 patients following corrective heart surgery.
A Mysterious Extrafraction in the Gamma Area of Protein Electrophoresis in Dialysis Patients is Found to be Fibrinogen
Authors: Hombrouckx R. , Gilbert I.
Published: July 2010

The appearance of a heretofore unnoticed extrafraction in the gamma protein electrophoresis of 17 dialyzed patients was linked to the modified Shaldon dialysis catheter. Medication interference, infection, and immunological or hematological disease as causative factors were ruled out. After initial contradictory results, the extrafraction was determined to be fibrinogen, present because of the slow release of heparin contained in the catheter, so that electrophoresis was performed on plasma instead of on serum.
Albumin Adsorption and Retention on C18‐Alkyl‐Derivatized Polyurethane Vascular Grafts
Authors: Eberhart Robert C. , Munro Mark S. , Williams Geraldine B. , Kulkarni Padmakar V. , Shannon W. Allen , Brink Bruce E. , Fry William J.
Published: July 2010

Abstract: The short‐term albumin affinity and thrombo‐resistance of a polyether polyurethane vascular graft have been improved. The method is based on the C18 alkylation of the polymer. Thrombus formation by a planimetric technique and albumin retention on wire‐reinforced polyurethane tubes, both C18 alkylated and untreated, were measured in short‐term (4‐h) exposure at femoral arterial sites in the dog. 125I‐Albumin was preadsorbed on tubes and then exposed to blood for successive 2‐h periods. Albumin uptake on alkylated tubes prior to blood exposure and retention following 2 h of blood exposure were significantly greater than on controls. Following a fast desorption phase in blood, the remaining albumin was more slowly desorbed from alkylated than from control tubes. Reincubation with albumin and blood reexposure produced a similar tendency, suggesting blood conditioning does not reduce the albumin affinity‐enhancing property of C18 alkylation in the short term. Blood‐preconditioning experiments suggested endogenous albumin has a high affinity for the C18‐alkylated surface. Scanning electron microscopic examination showed thrombus and platelet densities were higher on control than on alkylated surfaces. These results suggest in vivo albumin affinity is increased for C18‐alkylated polyurethane, which may be linked to decreased thrombus formation on these surfaces.
Increased Drainage Volume in Intermittent Peritoneal Dialysis Using a Two‐Bag, Low Hydrostatic Pressure Drainage System
Authors: Pomeranz Avishalom , Korzets Zeev , Bernheimfrom Jacques
Published: July 2010

Abstract: Adequate drainage volume (DV) is a prerequisite for long‐term success of intermittent peritoneal dialysis (IPD). Ultrafiltration (UF) is basically determined by the interplay of two major forces: a driving osmotic force created by a hyperosmolar dialysate solution versus an opposing force—the intraperitoneal hydrostatic pressure. Conventional drainage procedures (CS) are capable of achieving a fluid volume of 3 L per bag. We found that this intrabag volume corresponds to an intrabag hydrostatic pressure of 60 cm water. Because this drainage system is closed, the intrabag hydrostatic pressure reflects intraperitoneal hydrostatic pressure. A low‐pressure system (LPS) was devised to evaluate the possible influence on DV of reducing HP. Our results show that such LPS does indeed significantly improve DV, using a decreased number of exchanges. The residual volume and its glucose concentration (in a 1.5‐g/dl exchange) were measured with CS. When followed by an 4.25‐g/dl exchange, an 11% reduction in glucose concentration was evident. Thus, the osmotic driving force may also be impaired by incomplete drainage. To obtain maximal DV during IPD, a LPS should be used. This could be achieved by using 2 L dialysate in 3‐L bags.
Evaluation of ß2‐Microglobulin Removal with High‐Performance Hemodiafiltration
Authors: Kinugasa Eriko , Akizawa Tadao , Kitaoka Tateki , Koshikawa Shozo
Published: July 2010

Abstract: Several lines of evidence suggest that ß2‐mi‐croglobulin (ß2M) accumulation in long‐term hemodialysis (HD) patients results in so‐called dialysis‐associated amyloidosis (DAA), which is clinically manifested by carpal tunnel syndrome, osteoarthropathy, and the other organ involvements. For the purpose of preventing the ß2M accumulation, the efficiency of (ß2M removal during hemodiafiltration (HDF) with high‐performance membranes (HPM), hemofiltration (HF), HD, and charcoal hemoperfusion was evaluated. Among 27 patients treated with these methods, significant (ß2M removal was noted in HDF with HPM and HD with polyacrylonitril (PAN) membrane. However, treatment of HDF with HPM for more than 6 months caused no remarkable improvement in clinical symptoms of patients, and serum ß2M levels decreased in only two out of 15 patients. These results imply that ß2M might be most effectively removed by HDF with HPM and HD with PAN membrane, but further long‐term studies will be necessary to conclude whether these procedures could become successful therapeutic regimen for DAA.
Vascular Access for Continuous Arteriovenous Hemofiltration in Infants and Young Children
Authors: Zobel Gerfried , Trop Marija , Beitzke Albrecht , Ringy Ekkehard
Published: July 2010

Abstract: The blood flow through the hemofilter device is the key point for ultrafiltrate production during continuous arteriovenous hemofiltration. It mainly depends on arteriovenous pressure gradient and vascular access, which is the major problem for arteriovenous hemofiltration in infants and small children. In infants, we inserted short 18‐20 gauge catheters into the radial or brachial artery and the internal jugular vein and achieved mean blood flow and ultrafiltration rates of 6.5±2.2 and 1.3±0.3 ml/min, respectively. In small children, we placed 4 or 5 French catheters into the femoral vessels, and achieved mean blood flow and ultrafiltration rates ranging from 18.5 to 63.6 and 1.9 to 6.9 ml/min, respectively. The only catheter‐related complication was a femoral artery thrombosis, which needed surgical revision. These results show that vascular access for arteriovenous hemofiltration in infants and small children provides sufficient blood flow through the device for ultrafiltrate production.
Effect of Drive Mode of Left Ventricular Assist Device on the Left Ventricular Mechanics
Authors: Nakamura Takao , Hayashi Kozaburo , Seki Junji , Nakatani Takeshi , Noda Hiroyuki , Takano Hisateru , Akutsu Tetsuzo
Published: July 2010

Abstract: Pneumatically driven left ventricular assist devices (LVADs) were acutely implanted between the left atria and the descending aortas of dogs, and were driven in five pumping modes: electrocardiogram synchronous modes with the duty factors of 1:1, 2:1, and 4:1, and asynchronous modes with the pulse rates of 60 and 80 beats/min (bpm). The ventricular diameter and myocardial segment length were measured by an ultrasonic displacement meter and implantable miniature sensors. Bulk mechanical work of the left ventricle and regional mechanical work of the myocardium were calculated from these dimensions and the left ventricular pressure. LVAD reduced the bulk mechanical work of the left ventricle by 30‐50% and the regional work by 30‐60%. The mean aortic pressure and the total flow (=aortic flow+pump bypass flow) were highest in the 1: 1 synchronous pumping mode, which indicates that this mode is most effective to maintain the systemic circulation and coronary blood flow. Asynchronous pumping and synchronous pumping with 2:1 duty factor were most useful to reduce the mechanical work of the left ventricle.
Titanium Catheter Tip for Peritoneovenous Shunts
Authors: Franco Dominique , Labianca Michele , Smadja Claude , Fragoso José , Halabi Samer
Published: July 2010

Abstract: Early obstruction of the venous tubing is a frequent complication after peritoneovenous (PV) shunting for ascites in cirrhosis and results in a high incidence of shunt failure. A titanium catheter tip, developed because of this material's thromboresistance, was employed in 13 consecutive cirrhotic patients receiving a LeVeen shunt for intractable ascites. While the mean interval before shunt occlusion was 4±3 months in our previous studies, none of the patients in the present series had venous catheter occlusion during follow‐up, which averaged 8±2 months. The use of titanium in the venous tubing of PV shunts may significantly prolong the patency and function of these devices.
Proteins Adsorbed on Hemodialysis Membranes Modulate Neutrophil Activation
Authors: Kuwahara T. , Markert M. , Wauters J. P.
Published: July 2010

Abstract: The rapid adsorption of plasma proteins is one of the initial events that occur when blood enters into contact with an artificial surface. This study investigates adsorption of plasma proteins in vitro by different types of dialysis membranes and how it influences neutrophil oxygen radical production. The recovery of proteins varied between the membranes and was by far the largest on polysulfone. Electrophoresis of the proteins removed indicated that albumin was present on all of the membranes. A specific band at 45 kD was observed on polysulfone, whereas a band at 12–14 kD was seen on polysulfone and polyacrilonitrile. The adsorbed proteins enhanced or reduced the ability of the membranes to stimulate neutrophil superoxide production, as measured by cytochrome‐C reduction. The complement system was involved in this stimulation only on some membranes. Therefore, protein adsorption and neutrophil activation appear to take part in the membrane bioincompatibility process.
Experimental Acute and Chronic Vascular Access Through the Femoral Vessels: Hemodynamic Study in Dogs
Authors: Hatzibaloglou Ananias , Grekas Dimitrios , Papaconstantinou Christos , Kiskinis Dimitrios , Sapikas Ioannis , Pyrpasopoulos Marios , Aletras Homer
Published: July 2010

Abstract: In a side‐to‐side fistula between femoral artery and vein, an external “shunt” was created that simultaneously connected the distal femoral vein and the proximal femoral vein in 14 normal dogs with weight ranging from 14 to 28 kg. Blood flow and pressure alterations of different sites of this experimental model of vascular access were studied. The results showed that the degree of blood flow on these two vascular communications depends on the structural integrity of the femoral artery with adequate blood flow and blood pressure. Also, the correct connection of external shunt with the fistula is of equal importance. It is suggested that the blood pressure as well as the blood flow rate of these two vascular communications were adequate to allow performance of acute and chronic hemodialysis.
Plasma Adsorption Using Bilirubin‐Adsorbent Materials as a Treatment for Patients with Hepatic Failure
Authors: Morimoto Taisuke , Matsushima Munehiro , Sowa Nobumasa , Ide Koki , Sawanishi Kenji
Published: July 2010

Abstract: In order to achieve a higher degree of improvement in patients with postoperative hepatic failure, the effects of plasma adsorption (PA) using a serial connection of noncoated charcoal (N 350) and a new bilirubin adsorbent material, styrenedivinylbenzene (BR350), were investigated both experimentally and clinically. After in vitro perfusion of high bilirubin containing plasma through these columns for 3 hours, total bilirubin levels were drastically reduced to 21% of the preperfusion level in the serial connection of N 350 and BR 350, while it remained high at over 40% in the single use of each column. Total branched chain and aromatic amino acid levels were also drastically reduced in the serial connection of these columns to 50, 40, and 7%, respectively, while the total amino acid levels remained high at 87% in the single use of BR 350. The combination of these columns enhanced rather than interfered with one another. Patients who received this treatment achieved an initial reduction of plasma total bilirubin and aromatic amino acids of 57 ± 6 and 84 ± 7, respectively. Although the long‐term prognosis for these patients was negative, improvement of clinical and laboratory findings were actually obtained by this treatment. This PA system could provide a possibility for an improved supportive therapy for hepatic failure, especially for patients with hepatic coma and hy‐perbilirubinemia.
Wick Technique: Reference Method for Implanted Glucose Sensors
Authors: Fischer Uwe , Ertle Rainer , Rebrin Kerstin , Freyse Ernst‐Joachim
Published: July 2010

Abstract: The control of function of experimentally implanted glucose sensors needs an independent reference method. Employing saline‐impregnated cotton threads, an implanted wick‐technique was adopted in dogs to obtain analytical specimen from the subcutaneous interstitial fluid compartment. By measuring the contents of potassium, calcium, and hemoglobin, the centrifuged wick fluid was validated to contain the interstitial concentrations of solutes after an equilibration time of —15 min. Between 2 and 25 mmol/L, the steady state subcutaneous glucose concentration is nearly identical to circulating glycemia. Slow alterations, as during an oral glucose tolerance test, (OGTT) are well paralleled by the levels in the wick fluid. During alterations, however, a distinct delay is observed. The wick‐based glucose levels are mirrored by the output of electrochemical sensors implanted at the same site. This method may be used in checking implanted sensors that can otherwise not be calibrated in situ.
Clinical Total Artificial Heart Bridging: Viennese Strategy and Experiences
Authors: Trubel Wolfgang , Schima Heinrich , Rokitansky Alexander , Müller Michael R. , Losert Udo , Wolner Ernst
Published: July 2010

Abstract: Worldwide the clinical use of total artificial hearts (TAH) for bridging the time until heart transplantation (HTX) has become part of HTX programs. At our clinic, TAH bridging has been performed in five deteriorating HTX candidates since 1986. Four patients suffered from dilative CMP and one patient from a large anterior wall infarction. Three times the ellipsoid heart and twice the Berlin TAH were implanted. After TAH implantation, the conditions of all patients improved. The accompanying dysfunctions of kidneys and other vital organs, which were due to cardiogenic shock, could be restored in the three patients who underwent subsequent HTX. Bridging periods lasted from 9 to 13 days. Two patients, however, could not be transplanted because of infection. Although three patients could be bridged until transplantation and were in good clinical conditions, the longest survival following two‐stage HTX was 40 days. In the future, complications like infection, bleeding, and transplant rejection have to be prevented to improve the long‐term results of Viennese TAH bridging.
Effects of Bicarbonate‐Containing versus Lactate‐Containing Peritoneal Dialysis Solutions on Superoxide Production by Human Neutrophils
Authors: Manahan Ferdinand J. , Ing Brian L. , Chan Joseph C. , Gupta Dinesh K. , Zhou Fang‐Qiang , Pal Indra , Rahman Mohamed A.
Published: July 2010

Abstract: Human neutrophils were isolated from healthy volunteers and exposed to either bicarbonate‐containing (pH 7.4) or lactate‐containing (pH 5.2) peritoneal dialysis solution in vitro. Superoxide production by neutrophils was measured by a method based on the superoxide dis‐mutase‐inhibitable reduction of ferricytochrome c. Bicarbonate‐containing peritoneal dialysis solution was found to be superior to the lactate‐containing one in facilitating the production of superoxide anion by human neutrophils.
Efficient Continuous Flow Washing of Red Blood Cells for Exogenous Agent Loading Using a Hollow Fiber Plasma Separator
Authors: El‐Kalay M. A. , Koochaki Z. , Schutz P. W. , Gaylor J. D. S.
Published: July 2010

Abstract:Red blood cells (RBCs) are naturally occurring and biodegradable and are therefore ideal in vivo exoge‐neous agent (EA) carriers. Before being loaded with the EAs, the RBCs are washed, a process that normally involves repeated centrifugation with an iso‐osmotic solution. Washing the RBCs can be achieved more efficiently and rapidly using a capillary hollow fiber plasma separator until the blood is 99.5% protein free. Here, a separator area of 0.25 m2was preferentially selected over a 0.5 m2device because the reduction in RBC washing time associated with the latter was considered insufficient to justify the use of the more costly (0.5 m2) separator. Mathematical modelling of this continuous flow system indicates that washing time is mainly dependent on the volume of blood to be processed and the filtration rate. Using the separator, 300 ml of blood can be washed in less than 15 min.
Artificial Placenta: Long‐Term Extrauterine Incubation of Isolated Goat Fetuses
Authors: Kuwabara Yoshinori , Okai Takashi , Kozuma Shiro , Unno Nobuya , Akiba Kazuhiro , Shinozuka Norio , Maeda Tsugio , Mizuno Masahiko
Published: July 2010

Abstract: Previously, this group reported on a system of extrauterine incubation of a goat fetus, in which the fetus is surrounded by artificial amniotic fluid and connected to the circuit with an ECMO (extracorporeal membrane ox‐ygenator) by the umbilical arteries and veins. The following is a summary of recent progress using an improved method of catheterization and a new system that included a dialyzer within the circuit. Nine goat fetuses were used in this experiment. Six goats were successfully incubated; the duration of their incubation was 146.5 ± 61.3 h (mean ± SD). The longest one was 236 h. Slowly progressive circulatory depression was thought to be the main cause of fetal death. Marked tendencies to bleeding and water retention were not observed in any cases. Stable serum electrolyte levels were maintained.
High‐Pressure Portable Pneumatic Drive Unit
Authors: Hete B. F. , Savage M. , Batur C. , Smith W. A. , Golding L. A. R. , Nosé Y.
Published: July 2010

Abstract: The left ventricular assist device (LVAD) of the Cleveland Clinic Foundation (CCF) is a single‐chamber assist pump, driven by a high‐pressure pneumatic cylinder. A low‐cost, portable driver that will allow cardiac care patients, with a high‐pressure pneumatic ventricle assist, more freedom of movement has been developed.

The compact and light‐weight configuration can provide periods of 2 h of freedom from a fixed position driver and does not use exotic technology.
Contractile Response to Electrical Stimulation of the Small Intestine in Anesthetized and Awake Dogs
Authors: Moritz Anton , Grundfest‐Broniatowski Sharon , Ilyes Laszlo , Kasick Jerry , Jacobs Gordon , Nosé Yukihiko
Published: July 2010

Abstract: To test whether small bowel contraction can be induced by electrostimulation similar to in vitro results in anesthetized and awake animals, five dogs had stainless steel electrodes implanted on the serosal surface of the jejunum and ileum. Fifty milliamperes of 500‐μs 910‐Hz currents induced a 50–80‐mm Hg pressure increase in the jejunum with a threshold of 25 mA. Transverse stimulation was studied long‐term in two dogs. The mean pressure change for 500‐μs 910‐Hz 25‐mA stimulation in 10 studies was 26 mm Hg (0–75). The thresholds ranged between 15 mA and currents not tolerated by the animal. For 200‐μs 1.67‐kHz 30‐mA stimulation, the mean pressure change was 28 mm Hg (0–75 mm Hg, n = 16). On 10 occasions, the pressure increased further after termination of the stimulus (off response), with a mean of 48 mm Hg (10–85). Electrical currents elicit a mechanical response in the small intestine of the intact animal, which resembles the in vitro observations. Currents necessary to evoke contractions in the physiologic range are tolerated by the trained animal.
Partial Substitution of Sodium Lactate for Sodium Acetate in the Bath Fluid for Hemodialysis
Authors: Torrente Jaime , Coronel Francisco , Herrero Jose A. , Macia Manuel , Barrientos Alberto
Published: July 2010

Abstract: To the authors knowledge, lactate (LA) has never been used in hemodialysis concentrates. A new concentrate has been designed in which a low acetate (AC) concentration is complemented with LA up to standard quantities of buffer with the aim of minimizing the side effects of AC. In 14 classically AC‐intolerant hemodialysis patients (low body surface area of 1.47 ± 0.15 m2, decrease of serum bicarbonate level during hemodialysis by 2 mmol/L or more, and postdialysis hyperacetatemia of >7.0 mmol/L) a concentrate with LA was used (Na, 138; K, 1.5; Ca, 1.75; Mg, 0.75; CI, 109.5; AC, 17.5; and D,L‐lactate, 17.5 mmol/L) and compared with the same bath with only AC as a buffer (35 mmol/L). Patients were blindly and randomly assigned to either the AC or the LA bath during six hemodialyses. Blood gases, AC, and L‐LA levels were measured before and after dialysis. The number of symptomatic hypotension episodes and other symptoms such as vomiting, headache, or cramps were recorded in each dialysis. The postdialysis pH showed the same increase with both concentrates. The AC dialysis caused a significant decrease in P CO2 (26.05 ± 2.48 versus 34.37 ± 2.24 mm Hg; p < 0.001) and bicarbonate level (15.84 ± 2.12 versus 19.82 ± 1.45 mmol/L; p < 0.001). Dialysis with LA showed a smaller decrease ii PCO2 (31.60 ± 2.00 versus 35.45 ± 2.25 mm Hg; p < 0.01) and the bicarbonate level remained stable (19.43 ± 1.8: versus 20.02 ± 1.91 mmol/L; NS). Final acetatemia wa: lower in LA dialysis (3.12 ±1.6 versus 9.73 ±1.6 mmol L; p < 0.001). Symptoms were less frequent in LA dial ysis (hypotension 30.9 versus 64.2%, p < 0.001; vomiting 4.76 versus 15.4%, p < 0.01; headache, 19.0 versu 33.3%, p < 0.01), with a similar percentage of bod1 weight loss (3.36 ± 1.05 versus 3.26 ± 1.35%; NS). Thi use of this LA and low AC concentrate might prevent thi side effects of standard AC dialysis with lower final A(levels and avoiding the serum bicarbonate level fall. Thi results of this prospective, double‐blind randomizei study indicate that LA and low AC dialysate decrease th incidence of hypotension and other symptoms in thi group of so‐called “slow AC metabolizer” patients. Thi two‐buffer concentrate does not require hemodialysi machines with expensive and complicated bicarbonat modules.
Temperature and Albumin Effects on Adsorption of Bilirubin from Standard Solution using Anion‐Exchange Resin
Authors: Davies Charles R. , Malchesky Paul S. , Saidel Gerald M.
Published: July 2010

Abstract: The efficacy of plasma bilirubin sorption for the treatment of patients with hepatic dysfunction can be determined by a quantitive evaluation of bilirubin adsorption. The objective of this study is to examine the effects of temperature (4–42°C) and albumin concentration (0.5–5.0 g%) on bilirubin removal from solution by an anion‐exchange resin. For a constant albumin concentration, adsorption increased with temperature. The adsorption isotherm curves did not show saturation at the lower temperatures. At a constant temperature, adsorption increased with decreasing albumin concentration. A one‐parameter model was used to describe the data for bilirubin adsorption at all temperatures and for all initial concentrations of bilirubin and albumin. This parameter increased monotonically with temperature and decreased monotonically with albumin concentration. From a practical clinical point of view, bilirubin sorption may be increased by operation of the sorbent column at above ambient temperature.
Effects of Cardiac Assist on the Bulk and Regional Mechanics of the Ischemic Left Ventricle in Dogs
Authors: Nakamura Takao , Hayashi Kozaburo , Seki Junji , Nakatani Takeshi , Noda Hiroyuki , Fukuda Sachito , Takano Hisateru , Akutsu Tetsuzo
Published: July 2010

Abstract: Pneumatically driven left ventricular assist devices (LVADs) were implanted between the left atria and the descending thoracic aortas of dogs and were counter‐pulsated synchronously with the electrocardiogram at 1:1 and 2:1 duty ratios. Seven pairs of miniature sonomi‐crometers were implanted into the left ventricle (LV) to measure the LV muscular length and diameter. Ischemia was induced by the ligation of the left anterior descending coronary artery (LAD). Bulk and regional mechanical work were calculated from these dimensions and the left ventricular pressure. LVAD reduced the bulk work in the ischemic and normal hearts not only in the 1:1, but also in the 2:1, pumping modes. The left ventricular bulk work measured under the pump‐off condition decreased progressively until around 2 h after the LAD ligation, and thereafter, it became constant. The regional myocardial work in the normal area of the ischemic heart was significantly decreased by the LVAD pumping (by 55%), whereas that in the ischemic area remained at near zero level regardless of pumping or nonpumping. The results obtained indicated that LVAD is useful not only to rest the severely damaged natural heart, but also to maintain the viability of ischemic myocardium.
Changes in Neutrophil Oxidative Potential in Patients Undergoing Cardiopulmonary Bypass with Polypropylene Hollow Fiber Oxygenators
Authors: Roccatello Dario , Formica Marco , Cavalli Guido , Amprimo Maria C. , Pignatelli Maria G. , Costa Paolo , de Paulis Ruggero , Quattrocchio Giacomo , Molino Andrea , Giordano Gianbeppe
Published: July 2010

Abstract: Neutrophil oxidative metabolism, C3d and β2 microglobulin levels, were assessed in nine consecutive patients undergoing cardiopulmonary bypass surgery with polypropylene hollow fiber oxygenators for open cardiac operations. Generation of oxygen free radicals by neutrophils was measured as luminol‐enhanced chemiluminescence after stimulation with opsonized Zymosan and phorbol myristate acetate. A significant increase in light emission was detected by using both of the chemiluminescence stimulators. Moreover, a remarkable and significant increase in C3d levels was found already at 10 min. Conversely minimal changes in levels of p2 microglobulin were detected during cardiopulmonary bypass surgery. These data suggest that the impact of the patient blood with the foreign surface of cardiopulmonary bypass results in activation of phagocyte cells with increased potential in oxygen consumption. These effects could be partially complement‐mediated.
Effect of Reuse on Dialyzer Efficacy
Authors: Garred Laurie J. , Canaud Bernard , Flavier Jean‐Louis , Poux Claude , Polito‐Bouloux Chantal , Mion Charles
Published: July 2010

Abstract: The effect of reuse on dialyzer efficacy was examined by measuring blood compartment volume and dialyzer mass transfer coefficient (maximum dialyzer clearance) as a function of dialyzer use number. The 102 polysulfone dialyzers tested (F60 and HF80, Fresenius) were reprocessed on Renatron machines using peroxy‐acetic acid as the dual cleansing and sterilizing agent. Each dialyzer was used an average of 14.4 ± 5.7SD times and was tested once (twice for 13/102 dialyzers) during a routine dialysis session at an arbitrary use number (7.6 ± 5.3; range 1 to 24). The parameters tested were found to decrease only marginally with reuse, corresponding to a blood compartment volume loss of approximately 1% (R = 0.04) over a 5‐week/15‐use period and a decrease in dialyzer mass transfer coefficient of ±3% (R = 0.07 and 0.06) over the same period for urea and creatinine, respectively. It was concluded that the loss in dialyzer efficacy is negligible over the average use period of almost 5 weeks per dialyzer.
Colon‐Cancer Screening in Dialysis Patients
Authors: Ajam Maher , Ramanujam Lakshmi S. , Gandhi Vasant C. , Leehey David J. , Ing Todd S. , Schnell Thomas G. , Daugirdas John T.
Published: July 2010

Abstract: The usefulness of colon‐cancer screening using stool‐guaiac testing has been established in large control populations, but not in dialysis patients. In 72 asymptomatic dialysis patients [51 treated with hemodialysis (HD), and 21 with peritoneal dialysis (PD)] who underwent outpatient stool occult blood testing, the test result was positive in 11 (15%) patients (8 HD and 3 PD). Eight of the 11 were investigated further by colonoscopy and, when deemed necessary by the treating physician, esophago‐gastroduodenoscopy and/or barium enema were also performed. A site of active bleeding was identified in three of the eight patients (hemorrhoids, telangiectasia, ulcerative colitis). In each of the five other patients, potentially bleeding lesions were identified: colonic polyps (two malignant and two benign) in four patients, Barrett's esophagus in one, diverticulosis in two, and colonic vascular deformities in two. These results were compared with those of a large ongoing fecal occult blood screening program in which the prevalence of positive stool occult blood tests is 5% and in which 42% of the positive patients have colonic neoplasms. Thus, although the baseline incidence of positive guaiac tests may be higher in dialysis patients than in nonuremic controls, our results suggest that stool guaiac testing of dialysis patients may not only be useful in detecting colonic polyps, but may also identify other previously unsuspected causes of gastrointestinal bleeding.
Biocompatibility of Hemoglobin Solutions. II. The Inflammatory Reaction of Human Monocytes and Mouse Peritoneal Macrophages
Authors: Simoni Jan , Feola Mario , Tran Rue , Buckner Mark , Canizaro Peter C.
Published: July 2010

Abstract: This study explored the inflammatory mechanism of toxicity of hemoglobin solutions (Hb‐S). Human monocytes and mouse activated peritoneal macrophages were incubated with seven different solutions. The first four consisted of non‐cross‐linked bovine Hb. Of these, Hb‐SI was incompletely purified of stromal phospholipids, Hb‐SII was contaminated with environmental bacterial endotoxins, Hb‐SIII was pure hemoglobin, and Hb‐SIV was pure Hb with the addition of superoxide dismu‐tase (SOD), catalase (CAT), and mannitol (M). The other three solutions were made of pure bovine Hb cross‐linked with different agents: Hb‐SV, reacted with glutaralde‐hyde; Hb‐SVI reacted with bis‐3,5‐dibromosalicyl fumarate (DBSF); and Hb‐SVII reacted with a ring‐opened dialdehyde derivative of 5′(pyro)‐phosphate of adenosine (ATP) (o‐ATP). The reaction of monocytes and macrophages was studied in terms of (a) O2‐derived radicals, as determined by the measurement of H2O2 and lipid peroxides; (b) complement factor C3a desArg; (c) 6‐keto‐prostaglandin F1α (stable metabolite of prostacyclin); and (d) TxB2 (stable metabolite of thromboxane) released into the culture supernatants. The most significant reactions were obtained with the solutions contaminated with stromal phospholipids or bacterial endotoxins. Pure Hb was less reactive. Further reduction in proinflammatory activity was achieved by the addition of oxygen radical‐scavengers (SOD, CAT, and M), or by the cross‐linking of Hb with DBSF or o‐ATP.
Clinical Indications for the Use of the “Poisk–IOM” Total Artificial Heart: The Experience of 13 Implantations in Humans
Authors: Shumakov Valeriy , Zimin Nikolay , Kazakov Eduard , Kormer Arkadiy , Vorontsov Sergey , Nikolaenko Eduard , Kozlov Igor , Drobyshev Alexander
Published: July 2010

Abstract: Success of total artificial heart (TAH) implantation as a temporary measure depends on three factors: proper patient selection, adequate surgical technique, and safe cardiac prostheses. From 1986 until March 1990, 237 patients with stagnant heart failure were examined. Sixty–one patients (27%) were put on a waiting list. Thirty–eight percent of them died awaiting transplantation. Thirteen TAH implantations were performed; nine patients who were not on a waiting list underwent TAH implantation by urgent indications. Four other patients underwent bridge TAH implantation after cardiac surgery. Our experience shows that the status of a patient before transplantation is a determinant factor and that it is possible to perform TAH implantation only in patients on a waiting list.
Present and Future of the Artificial Heart Driving System
Authors: Shumakov Valeriy Ivanovich , Itkin Georgy Pinkusovich , Sumin Alexander Victorovich , Mordashov Vecheslav Michailovich , Kiselev Uriy Mihailovich , Zimin Nikolay Konstantinovich , Drobyshev Alexander Alexandrovich
Published: July 2010

Abstract: The totally artificial heart (TAH) is now in development in two trends. First, there is the development of a bridge system for temporary support of cardiac function. The TAH with the extracorporeal pneumatic driving system Sinus–IS is more efficient and safer. Parallel with this, a portable pneumatic driving system has been developed. That can be considered a stage in the development of the second trend: a totally implantable TAH. This article reviews problems of building of the Micron energy system to be used in implantable TAH designs.
The Interaction of Heparinized Biomaterials with Human Serum, Albumin, Fibrinogen, Antithrombin III, and Platelets
Authors: Nemets Eugene A. , Sevastianov Victor I.
Published: July 2010

Abstract: The influence of the method of heparin (HEP) immobilization on human serum albumin (HSA), fibrinogen (FG), and antithrombin III (AT–III) adsorption, platelet adhesion, and activation on the surface of polyvinylchloride, polyurethane Vitur, and a copolymer of styrene and divinylbenzene was measured. The negative correlation between the degree of irreversibility of plasma protein adsorption and the amount of adsorbed AT–III for HEP, immobilized onto the polymer surface passivated with HSA, FG, and plasma was found. The same negative correlation was observed between the amount of AT–III adsorbed on these systems and the number of adhered platelets. Schemes of the interaction of surface bound–HEP with AT–III, including the influence of an irreversibly adsorbed protein layer and adhered platelets, have been proposed. The essential role of AT–III in heparinized biomaterials/platelet interaction has been shown. A new method of combined immobilization of HEP and platelet adhesion inhibitor has been elaborted on.
The Heterogeneity of Protein/Surface Interactions and Structural Alterations of Adsorbed Albumin and Immunoglobulin G
Authors: Kulik Eduard A. , Kalinin Igor D. , Sevastianov Victor I.
Published: July 2010

Abstract:The theoretical model is developed for the reversible and irreversible protein adsorption in kinetic regime by assuming the continuous energetical heterogeneity for protein/surface interaction and the possibility of structural alterations of adsorbed molecules. The simplest rectangular distributions of adsorption centers in energy of activation are used to explain the logarithmic kinetics of IgG and human serum albumin (HSA) adsorption on a quartz surface. To explain the Freindlich character of HSA adsorption onto a precoated surface, the exponential distributions of adsorption centers in energy of activation are used. A competitive analysis of some of the approaches allowed for the energetical heterogeneity of protein/surface interaction is made. The possibility of lateral electrostatic repulsion to form the logarithmic kinetics of HSA adsorption is checked experimentally. The influence of the temperature on HSA adsorption onto quartz is discussed also.
Elastic Siloxane Materials for Endoprosthetic Applications
Authors: Yuzhelevskii Yu. A.
Published: July 2010

Abstract: Data are reported on properties and application in the clinical practice of elastic silicone materials for medical uses and items thereof prepared in the S. V. Lebedev All–Union Synthetic Rubber Research Institute. The effect of the implants on the neighboring tissues and on the living organism as a whole is discussed. The possibility of using the materials under consideration for endoprostheses is demonstrated.
Antibodies to Toluene Düsocyanate in Patients with and without Dialysis Anaphylaxis
Authors: Grammer Leslie C. , Harris Kathleen E. , Shaughnessy Martha A. , Dolovich Jerry , Patterson Roy , Evans Susan
Published: July 2010

Abstract: In a majority of patients with anaphylaxis to dialysis, ethylene oxide has been identified as an etiologic agent. In a significant minority of patients sustaining such reactions, the antigen remains unidentified. Conflicting results have been published with regard to isocyanates as a possible antigen. The authors studied 19 hemodialysis patients with anaphylaxis in whom IgE against ethylene oxide–human serum albumin (ETO–HSA) was not identified (Group 1) and 25 peritoneal dialysis patients without anaphylaxis (Group 2). IgE against toluene diisocyanatehuman serum albumin (TDI–HSA) was found in one patient in Group 1, and a similar incidence of IgG against TDI–HSA in Group I (16%) and Group 2 (12%) was noted. The results do not suggest that IgE against TDIHSA is an important cause of dialysis anaphylaxis.