RESUMEN
BACKGROUND: Computerised tomographic (CT) peritoneography is performed on peritoneal dialysis (PD) patients to identify peritoneal boundary defects, dialysate maldistributions and loculated fluid collections. Iodinated contrast media are added to dialysate and infused through the dialysis catheter, and CT images are obtained. Chemical compatibility of contrast media with dialysis solutions has not been studied. In some institutions, pharmacists charged with oversight of compounded sterile preparations have placed a moratorium on the use of contrast media-dialysate mixtures until compatibility data become available. This study was undertaken to examine the compatibility of non-ionic iodinated contrast agents added to PD solution for the performance of CT peritoneography. METHODS: 100 mL of three non-ionic iodinated contrast agents, iopamidol 370 mgI/mL, iohexol 300 mgI/mL and iodixanol 320 mgI/mL, were mixed with 2 L 1.5% dextrose PD solution and stored at 2-8°C, 25°C and 40°C. Observations at predefined intervals were made over 5 days for visual appearance, turbidity, pH, drug concentration and chemical degradation. RESULTS: Iopamidol, iohexol and iodixanol were stable for 5 days under study conditions. The contrast-dialysate mixture remained clear and colourless, no turbidity changes observed, pH and drug concentrations were stable and no increase in existing impurities or new impurities were detected. CONCLUSIONS: The addition of commonly used non-ionic iodinated contrast agents to 1.5% dextrose dialysis solution is chemically stable, meeting the criteria set forth in the standards and guidelines of the US Pharmacopeia and the Institute of Safe Medication Practices. A protocol for performing CT peritoneography is recommended herein to facilitate patient safety and diagnostic reliability of the imaging study.
Asunto(s)
Diálisis Peritoneal Ambulatoria Continua , Diálisis Peritoneal , Humanos , Medios de Contraste/efectos adversos , Yohexol , Yopamidol , Reproducibilidad de los Resultados , Soluciones para Diálisis , Tomografía Computarizada por Rayos X/métodos , GlucosaRESUMEN
Home dialysis offers many advantages over in-center dialysis, but peritoneal dialysis and home hemodialysis are infrequently used. To better understand why, a survey of dialysis healthcare professionals (N = 273) in the United States was conducted to assess their knowledge, perceptions, and beliefs about home dialysis modalities. Most survey respondents demonstrated a lack of knowledge about home dialysis and perceived many barriers to home therapy, which may affect patient modality choice; however, 90% of respondents stated they would choose home dialysis for themselves if they required dialysis. Additional staff education may help reduce misperceptions, address knowledge gaps, and subsequently, increase use of home modalities.
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Servicios de Atención de Salud a Domicilio , Fallo Renal Crónico/terapia , Diálisis Renal , Humanos , Estados UnidosRESUMEN
UNLABELLED: ⦠BACKGROUND: The use of automated and continuous ambulatory peritoneal dialysis (APD and CAPD) prescriptions (Rxs) to achieve adequate uremic toxin and fluid removal targets is important for attaining optimal patient outcomes. One approach for predicting such Rxs is the use of kinetic modeling. ⦠METHODS: Demographic data and peritoneal membrane characteristics derived from a peritoneal equilibration test (PET) were available from 1,005 patients in North American centers who participated in a national adequacy initiative in 1999. Twelve patient subgroups were identified according to peritoneal membrane transport type and tertiles of total body water, assumed equal to urea distribution volume (Vurea). Each patient was then modeled using PD Adequest 2.0 to be treated by 12 CAPD and 34 APD Rxs using both glucose and icodextrin solutions to achieve adequacy targets of weekly urea Kt/V of 1.7 and 1 L of daily ultrafiltration (UF). Residual kidney function (RKF) was assumed to be 0, 2, 4, and 6 mL/min. Feasible peritoneal dialysis (PD) Rxs were identified where: 1) the 95% confidence limit achieved the goal of meeting the targets for urea Kt/V, daily UF, and both in 85%, 75%, and 70% of patients, respectively; 2) average PD solution dextrose concentration was < 2.5%; and 3) the number of daytime exchanges was minimized. ⦠RESULTS: Feasible PD Rxs were similar when RKF was ≥ 2 mL/min, allowing condensed recommendations based on RKF ≥ 2 mL/min or < 2 mL/min. Individuals with lower or slower membrane transport required relatively greater 24-h solution volumes to achieve adequacy targets when RKF fell below 2 mL/min. With increasing Vurea, there was disproportionately greater dependence on RKF to achieve targets. While multiple Rxs achieving urea Kt/V and daily UF goals were identified for all membrane transport types, use of icodextrin in the long dwell reduced the need for a midday exchange in APD, glucose exposure, required fill and 24-h dwell volumes, irrespective of RKF and Vurea. While these benefits were most notable in high and high-average transporters, similar results were also seen in low and low-average transporters. ⦠CONCLUSIONS: Kinetic modeling identified multiple APD and CAPD Rxs that achieved adequate uremic solute and fluid removal for patients, irrespective of RKF and Vurea. Use of icodextrin rather than glucose in the long dwell reduced the complexity of the PD regimen, total glucose exposure, and 24-h total treatment solution volumes. Irrespective of modeling, adequacy of any PD prescription should be based upon individual clinical evaluation both for volume and solute removal.
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Transporte Biológico/fisiología , Soluciones para Hemodiálisis/administración & dosificación , Diálisis Peritoneal/métodos , Peritoneo/metabolismo , Anciano , Femenino , Glucanos/administración & dosificación , Glucosa/administración & dosificación , Glucosa/metabolismo , Humanos , Icodextrina , Masculino , Persona de Mediana Edad , América del Norte , Prescripciones , Ultrafiltración/métodos , Urea/metabolismoRESUMEN
PURPOSE: Mathematical models of phosphorus kinetics and mass balance during hemodialysis are in early development. We describe a theoretical phosphorus steady state mass balance model during hemodialysis based on a novel pseudo one-compartment kinetic model. METHODS: The steady state mass balance model accounted for net intestinal absorption of phosphorus and phosphorus removal by both dialysis and residual kidney function. Analytical mathematical solutions were derived to describe time-dependent intradialytic and interdialytic serum phosphorus concentrations assuming hemodialysis treatments were performed symmetrically throughout a week. RESULTS: Results from the steady state phosphorus mass balance model are described for thrice weekly hemodialysis treatment prescriptions only. The analysis predicts 1) a minimal impact of dialyzer phosphorus clearance on predialysis serum phosphorus concentration using modern, conventional hemodialysis technology, 2) variability in the postdialysis-to-predialysis phosphorus concentration ratio due to differences in patient-specific phosphorus mobilization, and 3) the importance of treatment time in determining the predialysis serum phosphorus concentration. CONCLUSIONS: We conclude that a steady state phosphorus mass balance model can be developed based on a pseudo one-compartment kinetic model and that predictions from this model are consistent with previous clinical observations. The predictions from this mass balance model are theoretical and hypothesis-generating only; additional prospective clinical studies will be required for model confirmation.
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Fallo Renal Crónico/metabolismo , Fallo Renal Crónico/terapia , Modelos Biológicos , Fósforo/farmacocinética , Diálisis Renal , Humanos , Absorción Intestinal/fisiología , Tasa de Depuración Metabólica/fisiología , Factores de TiempoRESUMEN
BACKGROUND AND OBJECTIVES: Twenty-four-hour urine and dialysate collections provide accepted means to assess adequacy in peritoneal dialysis (PD). Recent publications suggest that creatinine clearance (CrCl) estimated from the Modification of Diet in Renal Disease (MDRD) equations (eCrCl) accurately approximates measured CrCl (mCrCl) derived from 24-hour collections of urine and dialysate and might serve as an alternative means to assess small-solute clearance and adequacy in PD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Post hoc analysis of data from patients enrolled in ADEMEX was used to assess agreement between mCrCl and eCrCl derived by four- and six-variable MDRD equations (4V-MDRDE and 6V-MDRDE, respectively). Additionally, associations among mCrCl, eCrCl, and survival were determined. RESULTS: Acceptable precision was observed between mCrCl and 4V-MDRDE-eCrCl and 6V-MDRDE-eCrCl for the entire cohort. Precision was markedly diminished when analysis was limited to functionally anuric patients with mCrCl < 12 ml/min per 1.73 m². Although there was no association between survival and mCrCl, for every 1-ml/min per 1.73 m² increase in 4V- and 6V-MDRDE-eCrCl, there was a 6% and 4% increase in risk of death, respectively. There was a negative association between MDRDE-eCrCl and creatinine appearance rates, suggesting MDRDE-eCrCl is significantly confounded by individual differences in muscle mass. CONCLUSIONS: MDRDE-eCrCl provides demographically comparable values to 24-hour urine and dialysate collections across the ADEMEX cohort. However, MDRDEs should not be used to assess small-solute removal or adequacy in individual PD patients or to predict outcome in any cohort of patients over narrow ranges of limited clearance.
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Creatinina/sangre , Soluciones para Diálisis/uso terapéutico , Dieta , Tasa de Filtración Glomerular , Fallo Renal Crónico/terapia , Modelos Biológicos , Diálisis Peritoneal , Análisis de Varianza , Biomarcadores/sangre , Biomarcadores/orina , Creatinina/orina , Soluciones para Diálisis/metabolismo , Femenino , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/fisiopatología , Fallo Renal Crónico/orina , Análisis de los Mínimos Cuadrados , Masculino , Persona de Mediana Edad , Diálisis Peritoneal/efectos adversos , Diálisis Peritoneal/mortalidad , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Reproducibilidad de los Resultados , Factores de Tiempo , Resultado del TratamientoRESUMEN
Thrombotic thrombocytopenic purpura (TTP), characterized by thrombocytopenia and microangiopathic hemolytic anemia, is a relatively rare disorder. The majority of cases have no defined causes. TTP has been reported in association with many drugs, but not with imatinib mesylate. We report a 22-year-old African-American woman who developed idiopathic hypereosinophilic syndrome. She was treated with imatinib mesylate and subsequently developed microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. TTP was diagnosed. A kidney biopsy was performed and was diagnostic of thrombotic microangiopathy. The patient was treated with plasma exchange and hemodialysis. Her eosinophilia resolved, but she remained dialysis dependent. To our knowledge, this is the first case report of the possible association between imatinib mesylate and TTP.
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Inmunosupresores/efectos adversos , Piperazinas/efectos adversos , Púrpura Trombocitopénica Trombótica/inducido químicamente , Pirimidinas/efectos adversos , Lesión Renal Aguda/etiología , Lesión Renal Aguda/terapia , Adulto , Benzamidas , Terapia Combinada , Femenino , Fiebre de Origen Desconocido/etiología , Humanos , Síndrome Hipereosinofílico/complicaciones , Síndrome Hipereosinofílico/tratamiento farmacológico , Mesilato de Imatinib , Inmunosupresores/uso terapéutico , Enfermedades Linfáticas/etiología , Piperazinas/uso terapéutico , Intercambio Plasmático , Pirimidinas/uso terapéutico , Diálisis Renal , Oclusión de la Arteria Retiniana/etiologíaRESUMEN
BACKGROUND: The National Kidney Foundation has recently published the Kidney Disease Outcomes Quality Initiative (K/DOQI) Clinical Practice Guidelines for Bone Metabolism and Disease in Chronic Kidney Disease (CKD). According to these guidelines, in patients with stage 5 CKD, the adjusted calcium level should be 8.4- 9.5 mg/dl, the serum phosphate should be 3.5-5.5 mg/dl, the calcium phosphorous product should be <55 mg(2)/dl(2) and the intact parathyroid hormone (PTH) level should be 150-300 pg/ml. METHODS: In order to evaluate our ability to meet these targets, we reviewed laboratory parameters of bone and mineral metabolism of 140 patients over a 6-month period in an inner city hemodialysis unit. Serum calcium and phosphate levels were determined using standard assays and PTH levels were determined using the Nichols Intact PTH assay. RESULTS: We found that the levels of serum calcium and serum phosphorus fell within the range recommended by the K/DOQI guidelines 49 and 36% of the time respectively. 57% of the determinations for calcium x phosphorus product were <55 mg(2)/dl(2). PTH levels were within the recommended values in 20% of the determinations. Only 7% of the determinations met all four criteria simultaneously in spite of meeting other K/DOQI targets such as hematocrit and dialysis adequacy. CONCLUSION: These data indicate that current practice for the management of bone and mineral metabolism in hemodialysis falls far short of meeting the K/DOQI guidelines.
Asunto(s)
Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/metabolismo , Hiperparatiroidismo Secundario/metabolismo , Fallo Renal Crónico/metabolismo , Fallo Renal Crónico/terapia , Diálisis Renal , Anciano , Calcio/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fósforo/sangre , Guías de Práctica Clínica como Asunto , Resultado del TratamientoRESUMEN
BACKGROUND: Management of tunneled, cuffed, central venous catheters in hemodialysis (HD) patients with bacteremia remains a challenge. Attempts to salvage the catheter with systemic antibiotics alone have been associated with increased risk of metastatic infectious complications. METHODS: Retrospective case series of patients with infectious complications in a chronic dialysis unit, affiliated with a tertiary care university hospital. RESULTS: Between 1996 and 1999, when we treated HD catheter-associated bacteremia with systemic antibiotics alone, we encountered a clustering of 8 cases of paraspinal/vertebral infections in a population of 162 patients. After changing our protocol, i.e., routine catheter exchange over a guide wire at approximately 48 h, while on systemic antibiotic therapy, we did not encounter any new cases of paraspinal/vertebral infections over a 15-month period. CONCLUSION: Our experience suggests that routine exchange of tunneled, cuffed catheters over a guide wire in HD patients presenting with bacteremia may significantly reduce serious infectious complications, e.g., epidural abscess/vertebral osteomyelitis.
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Bacteriemia/terapia , Infecciones Bacterianas/prevención & control , Cateterismo Venoso Central/efectos adversos , Diálisis Renal/instrumentación , Enfermedades de la Columna Vertebral/prevención & control , Bacteriemia/etiología , Infecciones Bacterianas/etiología , Cateterismo Venoso Central/métodos , Remoción de Dispositivos , Discitis/etiología , Discitis/prevención & control , Absceso Epidural , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteomielitis/etiología , Osteomielitis/prevención & control , Diálisis Renal/efectos adversos , Estudios Retrospectivos , Enfermedades de la Columna Vertebral/diagnóstico , Enfermedades de la Columna Vertebral/etiologíaRESUMEN
Diets enriched with fish oil may favorably affect the vascular perturbations underlying synthetic graft thrombosis. Therefore, these studies were designed to test the hypothesis that diets enriched with fish oil would decrease the incidence of thrombosis in newly constructed polytetrafluorethylene grafts. A double-blind, randomized trial was conducted. Twenty-four patients were randomized to receive 4000 mg of fish oil or 4000 mg of control oil. Both preparations were enriched with antioxidants and deodorized with peppermint. Patients began therapy within 2 wk after graft placement and were monitored for 12 mo or until thrombosis developed. With a permuted-block randomization schedule, 12 patients received fish oil and 12 patients received control oil. The primary patency rates at 365 d were 14.9% for the control group and 75.6% for the fish oil-treated group. Survival analysis revealed a significant difference between fish oil-treated and untreated patients (P < 0.03, Mantel-Cox test), with a power of 90%. Moreover, analysis of covariables, including age of > or =50 yr, gender, race, body weight, diabetes mellitus, bleeding times, and lipid profiles, indicated that this effect occurred principally as a result of fish oil administration. Importantly, fish oil treatment also decreased venous outflow resistance and systemic BP, compared with control values. Fish oils possess unique biologic properties that favorably affect the incidence of polytetrafluorethylene graft thrombosis, and they thus represent a potential treatment strategy for the prevention of access thrombosis.