Dialyzer and machine technologies: application of recent advances to clinical practice

Although hemodialysis is a mature therapy, a growing population of patients with more complex medical problems and limitations on resources will require technological innovations to improve the safety, reliability and efficiency of the therapy. The past several years have seen design changes to dialyzers that have provided incremental improvements in small solute clearance and more substantial improvements in the clearance of large solutes. New functions have been added to dialysis machines that help ensure reliable delivery of the dialysis prescription and enable full advantage to be taken of improvements in dialyzer clearance of large molecules. In addition, feedback control systems have been developed that may help reduce the untoward side effects which many patients experience during hemodialysis. Whether or not a particular innovation enters routine clinical use will depend on demonstrating that it improves clinical outcomes, its cost, and, in some cases, on a more enlightened approach by regulatory authorities.

Population Requirements for Vascular Access Surgery

The native arterio-venous fistula provides the best access for haemodialysis. The dialysis population is growing in number, becoming more elderly, and has increasingly complex medical co-morbidity. The ability to establish and maintain optimal haemodialysis access in this population requires the planning and commissioning of operating and diagnostic facilities and the training of sufficient suitable surgical specialists. This article outlines the major factors that influence the demand for and requirements of a vascular access service for the renal failure population.

Sorbent dialysis in the third millennium

Thus, in a variety of ways, the unusual relationship between patient and machine in sorbent dialysis reduces the risks that are inherent with single pass systems. This pays dividends for both patients and professionals. Given the growing need for home and self-care dialysis in the new millennium, the time is right for the introduction of an updated, revitalized sorbent dialysis system.

Dialysis Patients and Cardiovascular Problems: Can Technology Help Solve the Complex Equation?

Patients with end-stage kidney disease undergoing chronic hemodialysis (HD) present higher mortality rates compared with the general population. Once patients are on HD, the risk of cardiovascular death is approximately 30 times higher than in the general population and remains 10-20 times higher after stratification for age, gender, and the presence of diabetes. About half the deaths of patients on dialysis are attributed to cardiovascular causes including coronary heart disease, cerebrovascular disease, peripheral vascular disease, and heart failure. The cardiovascular burden of the HD patient arises from three different sources: risks inherent to the patient and the uremic syndrome, traditional risk factors, and risk factors related to the dialysis therapy. Based on these considerations and the fact that several aspects of the dialysis procedure can either add to the cardiovascular burden or modify the existing burden, new technologies should be directed towards the approach of a potential 'cardioprotective dialysis therapy'; such an approach may be facilitated by the application of new techniques and advanced dialysis machines. Created to make dialysis easy and safe, new machines feature several options that make patient monitoring and online hemodiafiltration therapy routine procedures. These and other features will possibly make dialysis better tolerated and more efficient in protecting patients from undesirable or potentially fatal cardiovascular events.

Delivery of predialysis care in an academic referral nephrology practice

The purpose of this study was to obtain a detailed picture of the delivery of all aspects of pre-end stage renal disease (ESRD) care in an academic nephrology practice. The study consisted of a cross-sectional review of the charts of 111 patients with chronic kidney disease (CKD) (Creatinine >1.5 mg/dL for males, Creatinine > 1.3 mg/dL for females) followed either in a private practice or a public hospital clinic. Charts were reviewed for evidence of a number of quality of care items including the degree of blood pressure control, the use of angiotensin II blockade, treatment of anemia, bone disease, and cardiovascular risk factors, as well as evidence of dialysis orientation and vascular access placement. Compared with previous published studies, this study shows encouraging trends towards better outcomes in at least two areas with evidence of improvement in hemoglobin levels, use of angiotensin II blockade, and degree of blood pressure control. However it also reveals many areas where care could be improved. This was particularly true in the areas of access placement, bone and mineral metabolism, and cardiovascular disease. It will be interesting to see whether the recent introduction of CKD guidelines by the National Kidney Foundation (NKF) and the associated educational initiatives for primary care physicians and nephrologists that are planned will further serve to improve the management of CKD patients in the years to come.

Reviews: The Current State of Nonuremic Applications for Extracorporeal Blood Purification

Despite the commonly accepted indications for hemodialysis and extracorporeal depuritive techniques, some clinicians have come to rely on blood purification for clinical states where the targeted substance for removal differs from uremic waste products. Over the last decade, a number of studies have emerged to help define the application of extracorporeal blood purification (ECBP) to these "nonuremic" indications. This review describes the application of extracorporeal blood purification in clinical states including sepsis, rhabdomyolysis, congestive heart failure, hepatic failure, tumor lysis syndrome, adult respiratory distress syndrome, intravenous contrast exposure, and lactic acidosis. Additional comments are provided to review existing literature on thermoregulation and osmoregulation, including acute brain injury.

Prevalence of Ulnar Neuropathy in Patients Receiving Hemodialysis

BACKGROUND

Ulnar neuropathy can cause pain, weakness, and sensory changes in the hand and can result in functional impairment. Patients with end-stage renal disease receiving hemodialysis may be predisposed to ulnar neuropathy by factors such as arm positioning during hemodialysis, underlying polyneuropathy, and upper extremity vascular access.

OBJECTIVE

To determine the prevalence of clinically evident ulnar neuropathy in a cohort of 102 patients with end-stage renal disease receiving hemodialysis.

DESIGN

All eligible patients in a single dialysis unit were screened for symptoms and signs of ulnar neuropathy. Those with at least 1 symptom or sign underwent nerve conduction studies to confirm the presence of ulnar neuropathy.

RESULTS

Clinically evident, electrophysiologically confirmed ulnar neuropathy was present in 37 (51%) of the 73 subjects with both screening and nerve conduction study data available. The true prevalence of ulnar neuropathy in this cohort was estimated between 41% and 60%.

CONCLUSIONS

There is a high prevalence of ulnar neuropathy in patients with end-stage renal disease receiving hemodialysis, which has not been previously recognized. The high prevalence of ulnar neuropathy in this population suggests that preventative efforts are indicated to prevent this functionally limiting complication.

Hemodialysis – From Early Days to Tomorrow

The Nestor of chronic dialysis, Belding Scribner, was well aware of most problems which plague hemodialysis to this day, but the major problem we are confronted with today has emerged much later, i.e. excessive cardiovascular mortality. Apart from modulating duration and frequency of dialysis, there is currently no logistic or technological solution immediately apparent to solve this problem. Elucidating and correcting the cardiovascular risk is the most important challenge to clinical nephrology today.

MARS--does it stand the test of time?

Artificial liver support systems have been tested for decades in the management of liver failure. Generally, after some promising results published as case series, the device either disappears or fails to show significant benefit in controlled trials. Recently, the molecular absorbent recycling systems (MARS) or extracorporeal albumin dialysis (ECAD) technique appears to have broken this trend. Responding to the title one could summarize by saying this technique so far has stood the test of time. Data in support of its use in acute liver failure (ALF) is still scant and difficult to assess. However, in a well known but not very well defined entity of acute on chronic liver failure (AOCLF) the ECAD technique has been shown to improve survival compared to a similar randomized control group receiving standard supportive therapy. This well tolerated liver support system has real potential for widespread application if further well designed multicenter clinical trials continue to support its effectiveness. Its future lies probably in the management of the moribund hospitalized patient on the transplant list awaiting a donor liver.

Patients who try our patience

The outpatient dialysis industry is experiencing a dramatic growth in new patients. A shortage of professional nephrology staff, coupled with increasing frustration with the system on the part of a number of dialysis patients, contributes to an environment of frustration and negative behaviors. The dialysis industry lacks concise or practical definitions to describe these behaviors and respond with appropriate interventions. Patients may be labeled improperly and then discharged inappropriately and involuntarily. The TransPacific Renal Network, a nonprofit agency supported with funds from the Centers for Medicare and Medicaid Services, convened a volunteer multidisciplinary work group to address this issue. The group's tasks were to develop behavioral definitions specific to dialysis therapy that could be understood easily by any dialysis staff member, classify these definitions into at-risk categories, examine the parameters of a zero-tolerance policy, and provide objective pathways to guide staff interventions.

Diabetic nephropathy as a cause of end-stage renal disease in Egypt: a six-year study

The prevalence of diabetic nephropathy as a cause of end-stage renal disease (ESRD) in Egypt has been examined in small cross-sectional studies, with conflicting results. The need for a large-scale study prompted us to perform this 6-year multiple cross-sectional study. A sample of ESRD patients enrolled in the Egyptian renal data system was evaluated during the period 1996-2001 for the prevalence of diabetic nephropathy. Prevalence gradually increased from 8.9% in 1996, to 14.5% in 2001. The mean age of patients with diabetic nephropathy was significantly higher than that of patients with ESRD from other causes. Mortality was also significantly higher in diabetic patients with ESRD.