Tubular enzymuria on admission to the ICU is useful in predicting ARF. The cheapness and wide availability of automated assays for gamma GT and AP suggests that estimation of these enzymes in random urine samples may be particularly useful for identifying patients at high risk of ARF.

This study suggests that a single-dose protocol of Clexane is an effective and very convenient alternative to sodium heparin, but currently direct costs are about 16% more. We recommend an initial dose of 0.70 mg/kg.

BackgroundPhase III clinical studies have confirmed that enoxaparin is superior to standard heparin in reducing the rate of recurrent ischaemic events in patients with non-ST elevation acute coronary syndromes. Patients with moderate to severe renal impairment were, however, excluded from these studies. Due to the hydrophilic disposition of enoxaparin, accumulation is likely in patients with renal dysfunction, thereby increasing the risk of haemorrhagic complications if standard weight adjusted treatment doses are used. Arbitrary dose reduction has been repor ted to increase the risk of ischaemic events, presumably due to inadequate enoxaparin concentrations. AimThe aims of this study were to investigate the influence of glomerular filtration rate (GFR) on the pharmacokinetics of subcutaneously administered enoxaparin, and to develop a practical dosing algorithm in renal impairment that can easily be used at the bedside. MethodsThirty-eight patients, median age 78 years (range 44-87), mean GFR 32 ml min -1 (range 16-117) and mean weight 69 kg (range 32-95), presenting with acute coronary syndrome were recruited into the study. Approximately 10 anti-Xa concentrations were taken per patient over their period of therapy. A population pharmacokinetic model was developed using non linear mixed effects modelling techniques, utilizing the software NONMEM. Stochastic simulations were performed to identify the most suitable dosing regimen. ResultsThree hundred and thirteen anti-Xa concentrations were collected. A two compar tment, first order input model was identified as the best baseline model. Covariates found to improve model fitting were GFR as a linear function on clearance (CL) and weight as a linear function on the central volume compartment (V c ). The fraction of drug excreted unchanged ( F u ) was estimated at 71%. CL and V c from the final covariate model were estimated as; CL (l h -1 ) = 0.681 per 4.8 l hr -1 (GFR) + 0.229 V c (l) = 5.22 per 80 kg (total body weight) Correspondence Bruce Green,

No abstract

SUMMARY:Icodextrin is a starch-derived, high molecular weight glucose polymer, which has been shown to promote sustained ultrafiltration equivalent to that achieved with hypertonic (3.86%/4.25%) glucose exchanges during prolonged intraperitoneal dwells (up to 16 h). Patients with impaired ultrafiltration, particularly in the settings of acute peritonitis, high transporter status and diabetes mellitus, appear to derive the greatest benefit from icodextrin with respect to augmentation of dialytic fluid removal, amelioration of symptomatic fluid retention and possible prolongation of technique survival. Glycaemic control is also improved by substituting icodextrin for hypertonic glucose exchanges in diabetic patients. Preliminary in vitro and ex vivo studies suggest that icodextrin demonstrates greater peritoneal membrane biocompatibility than glucose-based dialysates, but these findings need to be confirmed by long-term clinical studies. This paper reviews the available clinical evidence pertaining to the safety and efficacy of icodextrin and makes recommendations for its use in peritonal dialysis.

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The peracetic acid-based sterilant Renalin® is increasingly being used for reprocessing hemodialyzers. In order to evaluate the effects of reprocessing on (32-microglobulin (β₂M) kinetics and complement activation in chronic hemodialysis patients, we compared 4 dialyzer membranes on 1st, 2nd and 4th use of the membrane. Dialysis with new cuprammonium rayon dialyzers (0.8 m²) for 4 h resulted in a nonsignificant increase in serum β₂M concentrations of 10.7% (corrected for changes in extracellular volume) and significant generation of the complement component C3a des Arg. On reuse, minimal changes in serum β₂M levels were noted and complement activation was absent. Dialysis with new cellulose acetate (CA, 1.5 m²), polyacrylonitrile (AN69 HF, 1.6 m²) or polymethylmethacrylate (PMMA, 1.6 m²) membranes resulted in significant decreases in serum β₂M levels (19.5, 31.7 and 50.8%, respectively). Reprocessing had negligible effects on the removal of β₂M by CA and AN69, but by the 4th use halved the effectiveness of PMMA. Reprocessing reduced the significant generation of C3a des Arg observed with new CA and PMMA membranes. We conclude that, except for PMMA, Renalin reprocessing has minor effects on the ability of the membranes to remove β₂M and improves the biocompatibility of all membranes studied.

Adverse physiologic effects accompany hemodialysis. Biocompatible dialyzer membranes may both limit oxidative stress and decrease beta2-microglobulin production, thereby reducing patient morbidity. We compared standard solute clearance, lipid, and antioxidant effects of a novel cellulosic membrane dialyzer modified with covalently bonded vitamin E (Excebrane Clirans E15, Terumo Australia) with standard cellulosic and polysulphone membrane dialyzers. Stable adult hemodialysis patients taking no lipid lowering or antioxidant therapy (n = 17; 9 male, 8 female) were recruited into a 10 week, prospective, unblinded study. Measurements were made at baseline on their usual dialyzer and after 2, 4, and 10 weeks of Excebrane use. Excebrane demonstrated good in vivo clearance of standard solutes relative to surface area. Predialysis beta2-microglobulin levels were unchanged with time and were significantly lower postdialysis than with cellulose acetate (p < 0.05). Oxidized low density lipoprotein levels as measured by nitrotyrosine residues were high predialysis, but tended to decrease with both membranes (p > 0.05). Total antioxidant status fell during dialysis (p < 0.0005), but plasma vitamin A and E concentrations increased (p = 0.007 and p = 0.02, respectively). Baseline vitamin A levels were high in all patients and, along with vitamin E, total antioxidant status and lipid profiles did not change over time with Excebrane use. Excebrane is an efficient, biocompatible membrane with no deleterious effects on beta2-microglobulin or lipids. More long-term study is merited.