Hemodialysis prevention

There has been a report suggesting that rapid removal of bromates, by hemodialysis, prevents the occurrence of irreversible hearing loss and post ATN renal dysfunction [34]. 

Indications Prevent clot formation in patients with DVTs and pulmonary embolism, provide anticoagulation during hemodialysis, prevention of postoperative clot formation after surgery, decrease risk of strokes, decrease risk of Ml in patients with atherosclerosis Common drug examples ... 

Fluid restriction is generally unnecessary as long as sodium intake is controlled. The thirst mechanism remains intact in CKD to maintain total body water and plasma osmolality near normal levels. Fluid intake should be maintained at the rate of urine output to replace urine losses, usually fixed at approximately 2 L/day as urine concentrating ability is lost. Significant increases in free water intake orally or intravenously can precipitate volume overload and hyponatremia. Patients with stage 5 CKD require renal replacement therapy to maintain normal volume status. Fluid intake is often limited in patients receiving hemodialysis to prevent fluid overload between dialysis sessions. 

Water-soluble vitamins removed by hemodialysis (HD) contribute to malnutrition and vitamin deficiency syndromes. Patients receiving HD often require replacement of water-soluble vitamins to prevent adverse effects. The vitamins that may require replacement are ascorbic acid, thiamine, biotin, folic acid, riboflavin, and pyridoxine. Patients receiving HD should receive a multivitamin B complex with vitamin C supplement, but should not take supplements that include fat-soluble vitamins, such as vitamins A, E, or K, which can accumulate in patients with renal failure. 

Blood cultures should be obtained for any patient receiving hemodialysis who develops a fever. Nonpharmacologic management of infections involves preventive measures with sterile technique, proper disinfection, and minimizing the use and duration of venous catheters for hemodialysis access. 

Pharmacologic management of infections should cover the gram-positive organisms that most frequently cause access-related infections. Patients who have positive blood cultures should receive treatment tailored to the organism isolated. Preventive measures for access-related infections include mupirocin at the exit site and povidone-iodine ointment. The recommendations of the NKF for treatment of infections associated with hemodialysis are listed in Table 23-9. 

It is believed that heparin acts by neutralizing a number of active blood coagulation factors, thus disrupting the transformation of prothrombin into thrombin. Heparin is used to prevent thrombo-formation in myocardial infarctions, thrombosis, and embolism, for maintaining liquid conditions in the blood in artificial blood drcnlation and hemodialysis. Synonyms of this drug are arteven, hepalen, leparan, Uquemin, panheprin, vetren, and many others. 

Abstract Two thirds of the nearly half a million deaths per year in the United States due to sudden cardiac death (SCD) is attributed to coronary artery disease (CAD) and most commonly results from untreated ventricular tachyarrhythmias. Patients with ischemic cardiomyopathy and left ventricular dysfunction are at highest risk for SCD, but this still defines only a small subset of patients who will suffer SCD. Multiple lines of evidence now support the superiority of implantable cardioverter defibrillator (ICD) therapy over antiarrhythmic therapy for both primary and secondary prevention of SCD in advanced ischemic heart disease. Optimization of ICD therapy in advanced ischemic cardiomyopathy includes preventing right ventricular pacing as well as the use of highly effective anti-tachycardia pacing to reduce the number of shocks. While expensive, ICD therapy has been shown to compare favorably to the accepted standard of hemodialysis in cost effectiveness analyses. 

Indications for use of parenteral iron, e.g. as fer-rioxidesaccharate or iron dextran, are in patients on hemodialysis and patients with a disease which prevents absorption from the gastrointestinal tract, in patients who are on long term parenteral nutrition and sometimes in patients with inflammatory bowel disease. Parenteral iron does not raise the hemoglobin level significantly faster than oral therapy and carries a risk of severe adverse reactions. Reactions to intravenous iron include headache, malaise, fever, arthralgias, urticaria and in rare cases anaphylactic reactions, which may be fatal. 

Epoprostenol is the natural occurring prostacyclin which is formed in vascular endothelial cells. It increases cyclic AMP in the thrombocyte and is a strong platelet aggregation inhibitor. It is used to prevent thrombotic complications during hemodialysis when heparin is contraindicated. As its duration of action is no longer than 30 minutes it has to be given as an intravenous infusion. 

Mechanism of Action An alkylating agent that inhibits DNAand RNA protein synthesis by cross-linking with DNA and RNA strands, preventing cell growth. Cell cycle-phase nonspedflc. Therapeutic Effect Potent immunosuppressant. Pharmacokinetics Well absorbed from the G1 tract. Protein binding low. Crosses the blood-brain barrier. Metabolized in the liver to active metabolites. Primarily excreted in urine. Removed by hemodialysis. Half-life 3-12 hr. 

Mechanism of Action A long-acting glucocorticoid that inhibits accumulation of inflammatory cells at inflammation sites, phagocytosis, lysosomal enzyme release and synthesis, and releaseof mediators of inflammation. Therapeutic Effect Prevents and suppresses cell and tissue immune reactions and inflammatory process. Pharmacohinetics Rapidly, completely absorbed from the G1 tract after oral administration. Widely distributed. Protein binding High. Metabolized in the liver. Primarily excreted in urine. Minimally removed by hemodialysis. Half-life 3-4.5 hr. 

Mechanism of Action A fixed-combination carbapenem. Imipenem penetrates the bacterial cell membrane and binds to penicillin-binding proteins, inhibiting cell wall synthesis. Cilastatin competitively inhibits the enzyme dehydropeptidase, preventing renal metabolism of imipenem. Therapeutic Effect Produces bacterial cell death. Pharmacokinetics Readily absorbed after IM administration. Protein binding 13%-21%. Widely distributed. Metabolized in the kidneys. Primarilyexcreted in urine. Removed by hemodialysis. Half-life 1 hr (increased in impaired renal function). 

Mecfianism of Action An anticonvulsant that inhibits burst firing without affecting normal neuronal excitability. Therapeutic Effect Prevents seizure activity. Pharmacokinetics Rapidly and almost completely absorbed through the GI tract. Protein binding less than 10%. Insignificant amount metabolized in liver. Excreted in urine. Removed by hemodialysis. Half-life 7 hr. 

Mechanism of Action An HMG-CoA reductase inhibitor that interferes with cholesterol biosynthesis by preventing the conversion of HMG-CoA reductase to meva-lonate, a precursor to cholesteroh Therapeutic Effect Lowers serum LDL and VLDL cholesterol and plasma triglyceride levels increases serum HDL concentration. Pharmacokinetics Poorly absorbed from the G1 tract. Protein binding 50%. Metabolized in the liver (minimal active metabolites). Primarily excreted in feces via the biliary system. Not removed by hemodialysis. Half-life 2.7 hr. 

As with methanol poisoning, early fomepizole or ethanol infusion and hemodialysis are standard treatments for ethylene glycol poisoning. Fomepizole, an inhibitor of alcohol dehydrogenase, has FDA approval for treatment of ethylene glycol poisoning in adults based on its ability to decrease concentrations of toxic metabolites in blood and urine and to prevent... 

Because the drug and the mobilized metals are excreted via the urine, the drug is relatively contraindicated in anuric patients. In such instances, the use of low doses of EDTA in combination with hemodialysis or hemofiltration has been described. Nephrotoxicity from EDTA has been reported, but in most cases can be prevented by maintenance of adequate urine flow, avoidance of excessive doses, and limitation of a treatment course to 5 or fewer consecutive days. EDTA may result in temporary zinc depletion that is of uncertain clinical significance. Analogs of EDTA, the calcium and zinc disodium... 

Small waste products such as urea pass through the dialysis membrane from the blood to the solution side where they are washed away, but cells, proteins, and other important blood components are prevented by their size from passing through the membrane. The wash solution is changed every 2 hours, and a typical hemodialysis treatment lasts for approximately 4-7 hours. 

Acute poisoning is treated with gastric aspiration and lavage combined with intensive supportive therapy, including thorough assessment of the patient plus measures to prevent respiratory failure. In cases of very severe poisoning, peritoneal dialysis or hemodialysis may be necessary. 

Hemoperfusion differs from hemodialysis in that the blood is passed over a resin or charcoal column. The drug becomes bound to the column and the clean blood returned to the body. Hemoperfusion units have adsorptive surface areas of several thousand square meters while hemodialysis devices have an effective dialysis surface limited to several square meters. Obviously, relatively sophisticated technology is required for these procedures and there is the need to prevent clotting in the circuit, which can produce complications. 

Two teenagers with neurological toxicity (serum concentrations 5.4 mmol/1 and 4.81 mmol/1) were treated successfully with hemodialysis followed by continuous venovenous hemofiltration, which prevented a post-dialysis rebound in serum lithium concentrations (554). 

Aluminium has a close chemical affinity with silicon, which may have a role in protecting against aluminium toxicity (94). Serum aluminium and silicon concentrations were measured in hemodialysis patients from four different centers. Although there was no relation across all centers combined, in one center there was a reciprocal relation in patients on home hemodialysis (who did not require reverse osmosis). Median (range) aluminium concentrations were higher, 2.2 (0.4-9.6) pmol/l when serum silicon was less than 150 pmol/l, and lower, 1.1 (0.2-2.8) pmol/l when serum silicon was greater than 150 pmol/l. In patients treated by hemodialysis without reverse osmosis, high serum silicon concentrations were associated with lower serum aluminium concentrations. Further work is needed to confirm a preventive role for silicon in the accumulation and subsequent toxicity of aluminium in dialysis patients. 

Although hemodialysis is effective in removing contrast media from the body, its ability to prevent contrast nephrotoxicity has been disappointing. Hemodialysis after contrast administration in patients with pre-existing renal impairment does not prevent contrast nephropathy (SEDA-22, 502) because of the very rapid onset of renal damage (SEDA-21,481) (SEDA-22,501), since the effect of contrast media on the kidney after intravascular... 

Berger ED, Bader BD, Bosker J, Risler T, Erley CM. Kontrastmittelinduziertes Nierenversagen lasst sich durch Hamodialyse nicht verhindern. [Contrast media-induced kidney failure cannot be prevented by hemodialysis.] Dtsch Med Wochenschr 2001 126(7) 162-6. 

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