Hemodialysis vancomycin

Metabolism/Excretion - In the first 24 hours, approximately 75% of a dose is excreted in urine by glomerular filtration. Elimination half-life is 4 to 6 hours in adults and 2 to 3 hours in children. About 60% of an intraperitoneal dose administered during peritoneal dialysis is absorbed systemically in 6 hours. Accumulation occurs in renal failure. Serum half-life in anephric patients is approximately 7.5 days. Vancomycin is not significantly removed by hemodialysis or continuous ambulatory peritoneal dialysis, although there have been reports of increased clearance with hemoperfusion and hemofiltration. 

Estimates of MDMF for several drugs are listed in Table 6.5. With the exception of vancomycin, baseline drug clearance values for functionally anephric patients (CL nepfi) are taken from either the intermittent hemodialysis or the continuous renal replacement references that are cited. In the first 2 weeks after the onset of acute renal failure, vancomycin CLamph falls from approximately 40 mL/min to the value of 6.0 mL/min that is found in patients with chronic renal failure (37). This latter value is included in Table 6.5... 

Pollard TA, Lampasona V, Akkerman S, Tom K, Hooks MA, Mullins RE, Maroni BJ. Vancomycin redistribution Dosing recommendations following high-flux hemodialysis. Kid Int 1994 45 232-7. 

Touchette MA, Patel RV, Anandan JV, Dumler F, Zarowitz BJ. Vancomycin removal by high-flux polysulfone hemodialysis membranes in critically ill patients with end-stage renal disease. Am J Kidney Dis 1995 26 469-74. 

Hearing loss due to vancomycin toxicity has been treated by hemoperfusion and hemodialysis (36). 

A 14-month-old girl with chronic renal insufficiency due to renal dysplasia was empirically treated with ceftazidime and vancomycin for fever. Her calculated creatinine clearance was 10 ml/minute/1.73 m. She erroneously received vancomycin 1.5 g in 3 doses 6 hours apart. Her serum creatinine concentration increased and her vancomycin concentrations remained markedly high (338 mg/1 5 hours after the third dose). The half-Ufe of vancomycin was 145 hours. Hearing loss developed. Continued charcoal hemoperfusion and hemodialysis were used to treat the disorder. Thrombocytopenia was noted as significant consequence of hemoperfusion. The patient did not fully recover her previous renal function and became dialysis dependent. The audiogram normalized by 6 months. 

Diarrhea developed in a 60-year-old man on chronic hemodialysis after 20 doses of parenteral vancomycin (250 mg at each dialysis) (57). Although culture for C. difficile was not performed, latex agglutination was positive for C. difficile toxin. 

Vancomycin is eliminated almost exclusively by renal excretion. In oliguria 1 g can produce therapeutic plasma concentrations for 10-14 days. Hemodialysis fails to remove vancomycin from the body to any significant extent. If renal function is compromised, even oral therapy with vancomycin can lead to high and potentially toxic serum and CSF drug concentrations (109). 

Hemodialysis with high-efficiency dialysis membranes resulted in a removal of plasma vancomycin of about 60% (calculated half-life 2 hours) in two children with initial plasma vancomycin concentrations of 238 gg/ml and 182 gg/ml (114). 

Vancomycin clearance is minimally altered by hemodialysis using standard cuprophane membranes. However, it is significantly increased using a high-flux polysulfone membrane. 

Chopra N, Oppenheimer J, Derimanov GS, Fine PL. Vancomycin anaphylaxis and snccessfnl desensitization in a patient with end stage renal disease on hemodialysis by maintaining steady antibiotic levels. Ann Allergy Asthma Immunol 2000 84(6) 633-5. 

C Treatment for catheter-related infections is often initiated empirically, with definitive therapy based on culture results and susceptibility. Dialysis catheters are usually permanently inserted lines, and patients on chronic hemodialysis are at higher risk for developing catheter-related infections secondary to staphylococcal species, particularly coagulase-negative staphylococci. Oral vancomycin is not appropriate because it does not achieve adequate blood levels to treat systemic infections. 

Fogel MA, Nussbaum PB, Feintzeig ID et al. Cefazolin in chronic hemodialysis patients a safe, effective alternative to vancomycin. Am J Kidney Dis 1998 32 401-409. 

The final component of the dialysis prescription that may affect drug clearance by dialysis is whether or not the patient has anthorized the unit to reuse his or her dialyzer. Currently, more than 75% of all dialysis units in the United States use this procedure to reduce the cost of chronic hemodialysis. The effect of dialysis filter reuse on the clearance of endogenous molecules such as urea, creatinine, and P2-microglobulin has been evaluated for many dialyzers. A decrease in urea and creatinine clearances and an increase in /S2-mictoglobulin clearance was observed with some, but not all, dialyzers. Only one center has evaluated the effect of reuse on drug clearance (cefazolin, ceftazidime, tobramycin, and vancomycin) following the first and tenth use of cellulose acetate, cellulose triacetate, and polysulfone... 

Matzke GR, Frye RF, Nolin TD. Vancomycin removal by low- and high-flux hemodialysis with polymethylmethacrylate dialyzers. J Am Soc Nephrol 1999 10 193A. 

Vancomycin is the drug of choice against serious infections caused by methicihin-resistant strains of Staphylococcus aureus and coagulase-negative staphylococci [172]. It may also be used for treatment of infections by gram-positive organisms in penicillin-intolerant patients. Vancomycin has been extensively used to treat endocarditis caused by streptococci, enterococci and staphylococci. The empiric treatment of intravenous catheter sepsis and hemodialysis vascular access infection by vancomycin has led to a linear increase in its use in the last decade [173]. Oral vancomycin is efficacious in the treatment of Corynebacterium difficile-mediated diarrhea. Of major concern is the recent emergence of vancomycin-resistant enterococcus strains [174,175]. 

Vancomycin should be used only to treat serious infections and is particularly us ul in the management of infections due to methicillin-resistant staphylococci and in severe staphylococcal infections in patients who are allergic to penicillins and cephalosporins. Vancomycin is less rapidly bactericidal than the antistaphylococcal J3-lactams (e.g., nafcillin or cefazolin) and may be less efficacious. Treatment with vancomycin is effective and convenient when there is disseminated staphylococcal infection or localized shunt infection in a patients receiving hemodialysis or peritoneal dialysis, because the drug can be administered once weekly or in the dialysis fluid. 

Vancomycin is not removed from the blood during hemodialysis, and no change in dosage is required. The answer is (E). 

Published guidelines on the management of catheter-related infections are in favor of the use of ALT for the treatment of catheter-related infections [24]. The in vitro stability of antibiotic-heparin combinations in CVCs was studied by Vercaigne et al. [25]. While ciprofloxacin produced immediate precipitation with heparin, cefazolin, vancomycin and ceftazidime at 10 mg/ml and gentamycin at 5 mg/ml were successfully incubated with heparin (5,000 U/ml) for 72 h in the central venous catheter lumen. Although free antibiotic in CVC solution was reduced, the final concentration was still sufficient for an effective antibiotic-heparin lock [25]. Good evidence is available to support ALT in the prevention of catheter-related bacteremia in patients on hemodialysis [26,27]. However, others have reported that the use of ALT may be limited due to antibiotic toxicity and the appearance of antibiotic-resistant microbial isolates [28, 29]. 

Ariano, R. E., Fine, A., Sitar, D. S., Rexrode, S., and Zelenitsky, S. A. (2005). Adequacy of a vancomycin dosing regimen in patients receiving high-flux hemodialysis. Am. J. Kidney Dis. 46, 681. 

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