Extracorporeal dialysis

The absorption and excretion of carbenicillin in man has been reported [396]. The antibiotic is not absorbed intact from the gut intramuscular injection (which is painful) often provides adequate serum levels (approximately 20 Mg/ntl) but infections with Pseudomonas strains having minimum inhibitory concentrations up to, or higher than, 100 Mg/ml require intravenous thbrapy to achieve such levels. No evidence of active metabolite formation has been obtained. Marked reductions in the half-life (and serum levels) of carbenicillin follow extracorporeal dialysis or peritoneal dialysis, the former producing the most striking effect [397]. These results were, of course, obtained in patients with severe renal failure. Patients with normal renal function rapidly eliminate the drug but, as with all penicillins, renal tubular secretion can be retarded by concurrent administration of probenecid. 

Siloxane-containing devices have also been used as contact lenses, tracheostomy vents, tracheal stents, antireflux cuffs, extracorporeal dialysis, ureteral stents, tibial cups, synovial fluids, toe joints, testes penile prosthesis, gluteal pads, hip implants, pacemakers, intra-aortic balloon pumps, heart valves, eustachian tubes, wrist joints, ear frames, finger joints, and in the construction of brain membranes. Almost all the siloxane polymers are based on various polydimethylsiloxanes. 

Extracorporeal dialysis Follow equipment manufacturers operating directions. Laboratory samples Add 70 to 150 units per 10 to 20 mL sample of whole blood to prevent coagulation of sample. 

Removal of a drug from the body may occur via a number of routes, the most important being through the kidney into the urine. Other routes include the bile, intestine, lung, or milk in nursing mothers. A patient in renal failure may undergo extracorporeal dialysis, which will remove small molecules such as drugs. 

Extracorporeal dialysis can be implemented for blood decontamination. Enzymes can be immobilized on dialysis cartridges (Klein and Langer, 1986). In that case, kcJKm has to be as high as possible and the flow rate reduced to increase the efficiency of the reactor. Moreover, accessibility of OP molecules to the enzyme active center must not be altered by the immobilization method or by matrix effects. The enzyme concentration per surface unit has to be maximized to reduce diffusion constraints. First order... 

Since 1960 discussion has focused on procedures for extracorporeal dialysis and since 1981 these have been used successfully (J. Feldman et al.). The ultrafiltration of ascitic fluid by means of haemodialysis and its subsequent reinfusion was described by E.R. Hwang et al. in 1982. Additional administration of foreign protein is not necessary. (145, 151, 177) A further development of ultrafiltration could be seen in the so-called cascade filtration or double ultrafiltration. (182) This procedure is described as safe, reliable and low in complications. 

The addition of heparin to the isolated rat diaphragm previously loaded with rubidium 86 results in change of the inflow of rubidium . Heparin has a permeabilizing action which appears to be due to mobilization of bound potassium and this can be related to a reduction of calcium in the perfusion solution. Karasek and Mourek.i conclude that heparin depresses oxidative processes through an effect on cell permeability it is possible that it adsorbs certain substances such as potassium chloride or acetylcholine. In extracorporeal dialysis , heparin causes an apparent decrease of 60 per cent in plasma calcium concentration. Heparin also forms a chelate-like compound with calcium ions " . This process is usually unimportant as heparin absorbs a maximum of only 5 per cent of its weight of calcium, but with intradermal, intramuscular or subcutaneous administration, heparin may deplete the capillary walls of calcium and cause them to become fragile. Heparin alsc decreases wound strength 6-14 days after operation in some experiments and may delay the union of fractures in bone repair . Heparin, but not chondroitin sulphate or hyaluronic acid, in tissue culture increases the amount of bone resorption in the presence of suboptimal concentrations of parathyroid extracts, and thus may be a cofactor in bone metabolism. ... 

Protein breakdown is accompanied by a loss of intracellular potassium, and starvation is associated with hyperkalemia. Hyperkalemia may seriously complicate uremia observed when severe renal failure occurs, and then the excess potassium should be eliminated by extracorporeal dialysis. 

Lim began at once to use two methods to identify and isolate the gastric secretory stimulant whose existence his joint paper with Ivy denied. As a young man in Hamburg, Heinrich Necheles had devised a method of extracorporeal dialysis using goldbeater s skin, peritoneal membrane, and when he joined Lim in China in 1925, Necheles improved the technique of what he called vivi-dialysis (Fig. 6-2). Lim himself added the technique of blood vessel anastomosis that could be used for cross-circulation and transplantation as well as for vivi-dialysis. ... 

Adsorbents are used in medicine mainly for the treatment of acute poisoning, whereas other extracorporeal techniques based on physico-chemical principles, such as dialysis and ultrafiltration, currently have much wider clinical applications [1]. Nevertheless, there are medical conditions, such as acute inflammation, hepatic and multi-organ failure and sepsis, for which mortality rates have not improved in the last forty years. These conditions are usually associated with the presence of endotoxin - lipopolysaccharide (LPS) or inflammatory cytokines - molecules of peptide/protein nature [2]. Advantages of adsorption over other extracorporeal techniques include ability to adsorb high molecular mass (HMM) metabolites and toxins. Conventional adsorbents, however, have poor biocompatibility. They are used coated with a semipermeable membrane of a more biocompatible material to allow for a direct contact with blood. Respectively, ability of coated adsorbents to remove HMM solutes is dramatically reduced. In this paper, preliminary results on adsorption of LPS and one of the most common inflammatory cytokines, TNF-a, on uncoated porous polymers and activated carbons, are presented. The aim of this work is to estimate the potential of extracorporeal adsorption technique to remove these substances and to relate it to the porous structure of adsorbents. 

F. Successful chnical apphcation of extracorporal albumine dialysis in a patient with benign recurrent intrahepatic cholestasis (BRIC). Z. Gastroenterol. 2001 39 (Suppl. 2) 13-14... 

Sturm, E., Franssen, CJtJM., Gouw, A., Staels, B., Boverhof, R., de Knegt, R.J., Stellaard, F., Biileveld, C.MA., Kuipers, F. Extracorporal albumin dialysis (MARS) improves cholestasis and normalizes low apo A-I levels in a patient with benign recurrent intrahepatic cholestasis (BRIC). Liver 2002 22 (Suppl. 2), 72-75... 

Mitzner, St.R., Stange, R., Klammt, S., Risler, T., Erley, C.M., Bader, B.D., Berger, E.D., Lauchart, W., Peszynski, P., Freytag, X, Hickstein, H., Loock, X, Lohr, X-M., Liebe, St., Emmerich, X, Korten, G., Schmidt, R. Improvement of hepatorenal syndrome with extracorporeal albumin dialysis MARS results of a prospective randomized, controlled clinical trial. Liver Transplant. 2000 6 277 — 286... 

SPAD Single-pass albmnin dialysis was the first method to be developed. The blood of the patient is extracorporeally dialyzed through an albumin-impermeable membrane against albumin in the secondary circuit. The loaded albumin is discarded. 

MET,S The modular extracorporeal hver support system was developed from BELS. In contrast to BELS, however, it consists of three modules (1.) a cell module with human hepatocytes, (2.) single-pass albumin dialysis and (i.) a dialysis module for constant venovenous haemofiltration. (100)... 

Faybik, P., Hetz, H., Baker, A., Bittermann, C., Berlakovich, G., Werba, A., Krenn, C.G., Steltzer, H. Extracorporeal albumin dialysis in patients with Amanita phalloides poisoning. Liver Internat. 2003 23 (Suppl. 3) 28-33... 

Extracorporeal blood purification therapies do not efficiently remove heavy metals or their salts. Chelating agents can be combined with dialysis modalities and hemoperfusion to improve the clearance of aluminum, iron, and other metals. 

Pond SM. Extracorporeal techniques in the treatment of poisoned patients. Med Ausf. 1991 154 617-622 Jaeger A, Sauder P, Kopferschmitt J. When should dialysis be performed in lithium poisoning A kinetic study in 14 cases of lithium poisoning. Toxicol Clin Toxicol. 1993 31 429-447... 

Its main use is in extracorporeal procedures, such as kidney dialysis. It has a very short lifetime in the body, though it can be given by continuous infusion in vivo. epoprostenol sodium epoprostenol. epOStane [ban. inn, usan] (Win 32729) is a synthetic prostaglandin carbonitrile derivative antiprogestogen, which has been investigated for use as an abortifacient and OXYTOCIC AGENT, and to induce labour. gppyTM M adrenaline. 

HD relies on good vascular access to the circulation of the patient to enable blood to be pumped around the extracorporeal circuit at a rate in excess of 300 mL per minute. This ahflity was not introduced until the 1960s, Although Kolff in Groningen Hospital in the Netherlands performed the first dialysis experiments in humans in 1943, the problem of dialysis support with long-term vascular access was not solved until Scribner developed the arteriovenous cannula in 1960, This was followed by the development of the surgically... 

The transfer of intracellular K" into ECF invariably occurs in acidosis as H shifts intraceHularly and shifts outward to maintain electrical neutrality. As a general rule, K concentrations are expected to rise 0.2 to 0.7 mmol/L for every 0.1 unit drop in pH. When the underlying cause of the acidosis is treated, normokalemia will rapidly be restored. Extracellular redistribution of may also occur in (1) dehydration, (2) shock with tissue hypoxia, (3) insulin deficiency (e.g., diabetic ketoacidosis), (4) massive intravascular or extracorporeal hemolysis, (5) severe burns, (6) tumor lysis syndrome, and (7) violent muscular activity, such as that occurring in status epilepticus. Finally, important iatrogenic causes of redistribution hyperkalemia include digoxin toxicity and P adrenergic blockade, especially in patients with diabetes or on dialysis. ... 

This syndrome may occur occasionally with the first use of a dialyzer, usually of the cuprophane type, and is an anaphylactic reaction with hypotension, wheezing, and flushing. Rarely it may be severe, resulting in death from marked bronchospasm and shock. In most cases the symptoms subside upon stopping the dialysis without returning the blood in the extracorporeal circuit to the patient, but a few patients require vigorous treatment for anaphylactic shock. 

Figure 1. Proposed heparin circuit. The extracorporeal device could be a renal dialysis unit or a pump-oxygenator. The heparinase reactor could be part of a blood filter to be used either continuously (in which case heparin would, be added, continuously at the start of the circuit) or at the end of an operation. Heparin could thus be confined to the extracorporeal circuit.

At present, synthetic blood filters are routinely placed at the effluent of extracorporeal devices such as the pump-oxygenator or artificial kidney to remove clots or aggregates formed during the perfusion. The filters used in oxygenators can be as large as 2 L, whereas those used in renal dialysis are only several milliliters. With further development, heparinase could be immobilized to polymers in these filters. In this case, the filter could remove both clots and heparin. 

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