ISSN:0250-8095    

DOI:10.1159/000168963

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0250-8095    

DOI:10.1159/000168964

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Treated end-stage renal disease continues to increase at an alarming rate in the US. There has been an exponential growth in the incidence rate between 1982 and 1991 at the rate of 8.76% per year. Approximately 218,042 patients received treatment for ESRD in 1991, of which 49,909 were new patients. Although the increase in the incidence rate is seen for all the major disease categories responsible for ESRD, diabetes mellitus, probably type 2, and hypertension are responsible for the bulk of the increase. African Americans and Native Americans have shown the most dramatic increase; diabetes being the major reason for both races, but for African Americans, hypertension is the leading cause of ESRD. A bulk of the increase in the ESRD patient population has been in the older age (greater than 65 years of age) group. The mortality rate for the ESRD patient population, and, specifically, for the dialysis population remains relatively high, with 1-year survival probabilities of approximately 78%. Some of the contributing factors cited for the high death rate, especially in the dialysis patient population include inadequate dialysis dose, low flux of the dialysis membranes, shortened dialysis times, an increase in the age of the ESRD population, and bioincompatible dialysis membranes. The effect of the widely practiced dialyzer reuse on dialysis patient morbidity and mortality remains unclear.

ISSN:0250-8095    

DOI:10.1159/000168965

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The interpretation of traditional serum urea and creatinine concentrations as indices of the severity of uremia requires major modifications in hemodialyzed patients. Although high urea concentrations usually signify worsening uremia and inadequate dialysis, low concentrations do not guarantee a good outcome. Urea production as modified by diet and other factors must also be included in a complete description of dialysis quantity and adequacy. The expression ‘Kt/V’ is a measure of hemodialysis that includes both urea removal and urea generation and is easy to measure from predialysis and postdialysis serum urea concentrations. Kt/V can be most precisely measured with the aid of mathematical models of urea kinetics during and between hemodialyses. Although a reliable measure of the dialysis dose received by most patients, the single-compartment model overestimates serum urea concentrations during hemodialysis and fails to predict the rebound immediately following dialysis. The classic two-compartment model that includes a factor for resistance to diffusion between the compartments, more accurately predicts the BUN profile but fails to account for blood flow-related disequilibrium including cardiopulmonary recirculation. Since solute disequilibrium reduces the effectiveness of hemodialysis, models that incorporate equilibrated urea concentrations both before and after hemodialysis are potentially more accurate tools for quantifying dialysis. Dialysate methods have the potential to accurately measure both solute removal which is the ultimate goal of dialysis, and patient clearance which is considered a better measure of the dialysis effect than dialyzer clearance. Application of these newer techniques requires major changes in sampling methods and changes in analytical equipment that will delay implementation. Meanwhile, analysis of blood-side urea concentrations using the single-compartment, variable volume model provides a reasonable estimate of Kt/V but must be interpreted with due consideration of its well-recognized pitfa

ISSN:0250-8095    

DOI:10.1159/000168966

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Hemodialysis treatments yielding inadequate amounts of dialysis, as defined by urea kinetic modeling, are partially responsible for considerable mortality and morbidity in the United States. In almost 50% of dialysis treatments resulting in a Kt/V of < 1.0, the culprit is impaired delivery of the prescribed amount of dialysis. The factors involved in impaired delivery of dialysis are many and often elusive. If present and widespread, a search for the causes of the problem entails careful examination of the equipment and nursing procedures. If impaired delivery is a sporadic and infrequent event, a patient-specific investigation should be undertaken. In either circumstance, a clear understanding of the principles and practical aspects of hemodialysis greatly assists the nephrologist as a sleuth.

ISSN:0250-8095    

DOI:10.1159/000168967

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

A drastic reduction in hemodialysis (HD) time has been based on the dialysis dose measurement in terms of urea Kt/V exclusively and on the use of high efficiency dialysers. It was subtly coupled to a de-emphasis of the use of HD to normalize blood pressure. In Tassin we have maintained long slow HD with an overall excellent patient survival. We analyze the influence of the different factors of this survival: the place of dry weight and blood pressure control without use of antihypertensive medication is emphasized, and the role of dialysis dose and nutrition is discussed. Adequacy should be defined in terms of these additive conditions. Long slow HD allows one to fulfill these conditions easily. Shortening of dialysis time should not interfere with the control of blood pressure.

ISSN:0250-8095    

DOI:10.1159/000168968

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The effective delivery of dialysis requires repeated reliable access to the central circulation capable of providing rapid blood flow. This access to the circulation continues to be the ‘weak link’ in the provision of long-term renal replacement therapy. Dialysis access malfunction is a major cause of inadequate dialysis delivery and venous stenosis is the leading cause of access malfunction and thrombosis. Careful monitoring of venous dialysis pressures and recirculation along with urea kinetic modeling and physical examination of the graft can prospectively identify the malfunctioning vascular access. When these indicators are used for referral for fistulogram, venous stenosis can be identified and corrected before graft thrombosis. Not only can preemptive repair of the vascular access prevent thrombosis, it also allows for more efficient dialysis delivery to the pati

ISSN:0250-8095    

DOI:10.1159/000168969

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Despite the widespread long practice of reuse there is continued criticism of the technqiue both in the media, journals and more recently at specially convened meetings. In the United States there are three principal sterilant/germicides used in reprocessing hemodialyzers: peracetic acid, formaldehyde and glutaraldehyde. The use of peracetic acid now exceeds that of formaldehyde while the more recent development of heat sterilization is only practiced in a few units. The major advantages of reprocessing include reduced cost, reduced first use syndrome and intradialytic symptoms which may be a result of increased biocompatibility with reuse. There is little data with regard to hospitalization and the recent reports of mortality rates are discussed. The major disadvantages associated with reprocessing include risks of infection, chronic exposure and accidental exposure to patients and staff to the sterilant germicide. We conclude that the reuse of dialyzers continues to be appropriate provided units follow the manufacturer’s guidelines, the AAMI Recommended Practices and have a method in place to ensure the prescribed dialysis prescription is delivere

ISSN:0250-8095    

DOI:10.1159/000168970

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0250-8095    

DOI:10.1159/000168971

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Water treatment is a vital aspect of hemodialysis in which knowledge and technical skills are of utmost importance. The recognition that nontuberculous mycobacteria can be resistant to certain germicides spurred the establishment of the current safety microbiologic standards for dialyzer reprocessing. Monitoring the dialyzer membrane integrity is as important as meeting the standards for bacterial and endotoxin levels for dialyzer reprocessing. Ensuring the use of product water that meets the chemical and microbiologic standards of the Association for the Advancement of Medical Instrumentation is necessary to reduce the incidence of endotoxemia and chemical hazards associated with the use of water for hemodialysis. The pathogenesis of febrile reactions during hemodialysis remains controversial. The weight of evidence, however, favors transmission of endotoxin fragments across dialysis membranes to induce mononuclear cell cytokine production.

ISSN:0250-8095    

DOI:10.1159/000168972

出版商:S. Karger AG    

年代:1996

数据来源: Karger