Handbook of dialysis

Includes information on the management of the pediatric patient undergoing dialysis. Defines the quality imperatives, roles , and responsibilities of dialysis facility medical directors and attending nephrologists. Updates nephrologists on the latest alternative dialysis modalities. Expert Consult eBook version included with purchase. This enhanced eBook experience allows you to search all of the text, figures, images, and references from the book on a variety of devices.

The ebook version that accompanies the book is user friendly and covers most of the information in the book. Ing No preview available — This is the essential dialysis manual, filled with up-to-date dialysis information, including preparation, procedures, surgery, problems and side-effects.

Obstetric and Gynecologic Issues. It would not be a book dislysis someone who wants to learn the very basics about cialysis and kidney failure. Buy the selected items together This item: Topics include screening, diagnosis and management of dialysis patients, including diagnostic work-ups, patient safety, and patient monitoring issues in acute dialysis and hemodialysis cases.

All Plastic and R We also would like to recognize Aleksandra Godlevska for her beautiful modern-art inspired cover art design. Although this book is well known in the nephrology community, it will be a useful tool for nurse practitioners and physician assistants for understanding the core concepts of the various modalities of dialysis.

Ing Limited preview — Handbook of Dialysis Paperback: Ing — Medical — — pages The revised, updated Fourth Dialysi of this popular handbook provides practical, accessible information on all aspects of dialysis, with emphasis on day-to-day management of patients. DaugirdasPeter G. Simple tables and figures are used appropriately and increase the ease of reading. It has been 7 years since the Fourth Edition; the long time interval reflects the relatively slow, incremental nature of improvements which have occurred in dialysis therapy during that time period.

Handbook of Dialysis John T. Products purchased from 3rd Party sellers are not guaranteed by the Publisher for quality, authenticity, or access to any online entitlements included with the product. A chapter on sorbent dialysis, present in the first two editions of the Handbook, but removed from the third and fourth editions as use of the REDY system dwindled, has been reinstated and modernized, given the anticipated imminent release of new sorbent-equipped hemodialysis machines for both in-center and home hemodialysis.

This is the essential dialysis manual, filled with up-to-date dialysis information, including preparation, procedures, surgery, problems and side-effects. Preface We are very fortunate and honored to present this Fifth Edition of the Handbook of Dialysis to the nephrology community.

English Choose a language for shopping. Anemia is common in CKD patients. As kidney disease advances, the incidence and prevalence of anemia increase. Anemia of CKD is multifactorial in etiology. The most common causes are erythropoietin deficiency, iron deficiency, and inflammation. Observational studies have sug- gested an increased risk of cardiovascular and renal complica- tions, lower quality of life, and higher mortality with a lower Hb level. Also, correction of anemia is associated with either no effect on kid- ney progression or an increased rate of ESKD.

Recent studies have found an association between exposure to high doses of ESA and heightened risk of adverse events. It is not clear to what extent this is causal or a reflection of the relatively high Hb targets used and the known association of ESA resistance with poor outcome.

Contemporary approaches to anemia management have now emphasize only partial correction of anemia, using the lowest possible dose of ESA, together with treatment of iron deficiency and inflammation. Initiation of ESA therapy and Hb thresholds.

KDIGO guidelines recommend to maintain the hemoglobin level between 9 and Treatment of anemia in CKD with ESA therapy should be individualized, and one of the main goals should be to reduce the need for blood transfu- sion. Types of ESA therapy. There are short-acting and long-acting ESAs.

Epoetin alfa, approved in and available world- wide, is a short-acting ESA with a half-life when given in- travenously of about 8 hours and 16—24 hours when given subcutaneously. A typi- cal dose in a CKD patient might be 4,—6, units sub- cut. The most widely used long-acting ESA is. The optimal administra- tion dosing schedule for darbepoetin alfa is once weekly a typical dose might be 20—30 mcg or every 2 weeks 40—60 mcg in a stable CKD patient. The dose does not differ if given by intravenous route or subcutaneous route.

The half-life is approximately hours. Frequency of administration and route of administration of ESAs. The frequency of ESA administration is usually influenced by patient convenience and efficacy considerations. Resistant anemia. Patients may be classified as having ESA hyporesponsiveness if they have no increase in Hb level from baseline after the first month of ESA treatment on appropriate weight-based dosing. In patients with initial or acquired ESA hypore- sponsiveness, evaluation for specific causes of poor ESA response should be undertaken.

Correction of iron deficiency. The causes of iron de- ficiency are multifactorial but include reduced absorption of iron; blood loss from either frequent blood draws or occult GI blood loss, and reduced nutritional intake.

Assessment of iron deficiency. Iron status iron stores and bioavailable iron levels should be evaluated regularly in patients with CKD. Ferritin is an iron storage protein and its serum levels reflect iron storage. Serum ferritin is also an acute phase reactant, however, and patients with CKD often exhibit chronic inflammation; therefore, the ferritin level should be interpreted cautiously in inflamed patients.

The transferrin saturation TSAT;. Therefore, before initiating ESA therapy, iron status must be addressed. Treatment of iron deficiency anemia.

Options for therapy de- pend on the stage of CKD and include oral and intrave- nous therapies. Oral iron therapy is the preferred method of treating nondialysis CKD patients and is recommended by KDIGO as an initial approach to treating iron deficiency.

Strategies to improve oral iron absorption include only tak- ing pills on an empty stomach, avoiding enteric-coated for- mulations, and avoiding ingestion of iron with phosphate binders. Intravenous iron may be needed in some patients who either do not respond to oral iron or have large ongoing losses of iron e. The use of low-molecular-weight iron therapy is recommended—low-molecular-weight dextrans, ferrous gluconate, iron sucrose, or ferumoxytol.

The use of high- molecular-weight iron dextran has been associated with an increased risk of severe anaphylaxis. Dosing strategies for oral iron aim at providing approximately mg of elemental iron daily, which is equivalent to ferrous sulfate mg three times daily; each pill providing 65 mg of elemental iron. If iron repletion goals are not met after a 1—3 month trial, it is appropri- ate to consider intravenous iron supplementation. Intra- venous iron can be administered as a single large dose or as repeated smaller doses, depending on the preparation used.

The initial course of intravenous iron treatment is to supply approximately 1, mg of iron. Iron status should be monitored every 3 months with TSAT and ferritin while a patient is receiving ESA therapy and more frequently when initiating or increasing ESA dose, in the setting of ongoing blood loss, or in circumstances where iron stores are likely to become depleted.

The man- agement of serum phosphorus, vitamin D, and parathyroid hormone PTH levels in dialysis patients is fully discussed in Chapter 36 and only issues pertinent to CKD will be dis- cussed here. Even in nonuremic pa- tients, mild serum phosphorus elevation is associated with increased cardiovascular risk.

Bonekey Rep. In a number of experimental renal failure models, hyperphosphatemia accelerates progression of renal failure. In such models, hyperphosphatemia stimulates parathyroid gland growth and PTH secretion.

Dietary management. Management includes a careful di- etary review to look for abnormally high consumption of foods rich in phosphorus, including dairy products, cer- tain colas, and processed meats. A careful review of the diet should be made with the goal of reducing consump- tion of foods containing phosphorus additives. Phospho- rus intake should be restricted to —1, mg per day 26—32 mmol per day. Target serum calcium and phosphorus levels. Previous rec- ommendations to maintain serum calcium at the high end of the normal range to ensure PTH suppression have been replaced by a strategy of keeping serum calcium to- ward the middle or low range of normal, to minimize the risk of vascular calcification.

Similarly serum phospho- rus levels should be maintained within the normal range. Phosphorus binders. Phosphorus binders may need to be used. The choices are described in Chapter It is pru- dent to restrict total calcium intake in CKD patients to about 1, mg per day 37 mmol per day KDOQI guide- lines are less restrictive and suggest a ceiling of 2, mg per day [50 mmol per day] , to minimize the risk of vascular calcification.

This means that if calcium salts are used as phosphorus binders, they may need to be combined with sevelamer, lanthanum, or, possibly, mag- nesium or one of the newer iron-containing phosphorus binders described in Chapter Use of sevelamer as a phosphorus binder has been shown to perhaps stabilize the rate of vascular calcification in CKD patients and to improve outcomes, although stud- ies are not definitive in this area.

This remains an active area of ongoing research. Serum parathyroid hormone levels. Control of serum PTH levels is important to minimize the degree of parathyroid gland hypertrophy and the risk of developing large, nonsuppress- ible glands. Hyperparathyroidism is associated with bone disease, and PTH may also act as a uremic toxin with ad- verse effects on many different organ systems. The control of PTH secretion is detailed in Chapter Frequency of measurement.

Target range of PTH. The intact PTH assay has been avail- able since and identifies both 1—84 and 7—84 PTH, and most bone biopsy studies on which target levels are based have employed this assay. Either assay can be employed for diagnosis and treatment of hyperparathyroidism in CKD, but the target PTH range will depend on the specific assay employed.

In dialysis patients, a target PTH range of 2—9 times normal is proposed as. Serum alkaline phosphatase. Alkaline phosphatase is present in bone and is an indicator of bone turnover rate. When high, particularly in combination with elevated serum PTH, serum alkaline phosphatase can be a reasonably good indicator of a hyperactive parathyroid gland that needs to be suppressed.

Vitamin D. In CKD patients, D levels are quite low, prob- ably because of lack of sunlight exposure and low ingestion of vitamin D—containing foods.

Vitamin D affects multiple organ sys- tems; most of these effects are beneficial, although excess vitamin D has been associated with vascular calcification and even accelerated renal failure. Recently active vitamin D sterol administration has been linked to improved sur- vival and improved cardiovascular outcomes in ESKD pa- tients. The mechanism of this survival benefit is not clear, and these are observational studies that need to be con- firmed.

In addition, in small randomized trials, vitamin D treatment has been shown to reduce proteinuria and slow progression of CKD Palmer and Strippoli, , and vita- min D also may improve ESA sensitivity and reduce anemia by reducing inflammation. Target serum levels of D in CKD.

Low serum lev- els of D have been linked to severe muscle weakness in elderly nonuremic patients. Because CKD patients typically have very low levels of D in the serum, for primary prevention, CKD patients should be supple- mented with at least 1,—2, IU of cholecalciferol per day, and higher doses may be needed.

This level of cholecalciferol supple- mentation does not affect GI absorption of calcium or phosphorus. To treat a low serum D level, the KDOQI bone disease guidelines recommended using ergocalciferol, which is slightly less effective than chole- calciferol and is available only in relatively large dosage forms designed to be prescribed weekly or monthly. Er- gocalciferol does have the advantage in the United States of being available as a formulary drug.

When to use active vitamin D preparations. In the more severe stages of CKD, conversion of D to 1,D in the kid- ney becomes suboptimal, and even with adequate stores of D, the serum levels of 1,D may remain low. In such situations, PTH often is not adequately suppressed. In stages 3 and 4 CKD patients in whom serum PTH re- mains above the target range despite adequate serum levels of D, the use of an active vitamin D preparation is indicated.

Choices and doses of active vitamin D prep- arations e. As in ESKD patients, when active vitamin D sterols are being given, the dose should be held or reduced in the presence of hypercalcemia or hyperphosphatemia. Cinacalcet is a calcimimetic drug that increases the sensitivity of calcium receptors on the parathyroid gland to calcium, resulting in a decrease in PTH secretion. The relative roles of cinacalcet versus active vitamin D sterols for PTH suppression in predialysis patients are not yet well defined.

Electrolyte and acid—base complications. A variety of electrolyte abnormalities may become apparent as kidney function de- clines. The most prominent is hyperkalemia. Acidosis can also develop although it is generally mild and usually with a normal anion gap until kidney function is severely impaired.

Treatment of acute hyperkalemia is discussed elsewhere. In the chronic setting, hyperkalemia usually is the result of rela- tively high dietary potassium intake, and especially, binge in- take of high potassium foods such as fruits. Hyperkalemia is also more commonly found in patients taking ACE inhibitors or angiotensin receptor blockers or mineralocorticoid recep- tor antagonists such as aldosterone.

It also is more common in patients taking nonsteroidal anti-inflammatory drugs as well as trimethoprim. The recent development of novel gastroin- testinal sorbents to prevent absorption of ingested potassium may allow more widespread use of renin—angiotensin aldoste- rone system RAAS antagonists.

Chronic metabolic acidosis results in increased resorp- tion of bone, and also has been associated with an increased rate of progression of CKD. The use of sodium bicarbonate is recommended to maintain the serum bicarbonate level at. The usual amount of sodium bicarbonate to give is 0. Alkali therapy has been shown to slow the rate of progression of CKD in several small random- ized trials.

Tasks here include preparation for dialysis or preemptive kidney transplantation; placement of vascular or peritoneal access; choosing the most appropriate mode and location of dialysis i. These are discussed in more detail in the next chapter.

References and Suggested Readings Agarwal R, et al. Chlorthalidone for poorly controlled hypertension in chronic kidney disease: an interventional pilot study. Am J Nephrol. American Diabetes Association. Executive summary: standards of medical care in diabetes— Diabetes Care. Functional range of creatinine clearance for renal drug dosing: a practical solution to the controversy of which weight to use in the Cockcroft-Gault equation. Ann Pharmacother. Daugirdas JT, ed. Handbook of Chronic Kidney Disease Management.

Wolters Kluwer; Philadelphia, Deedwania PC. Statins in chronic kidney disease: cardiovascular risk and kidney func- tion. Postgrad Med. Eckardt KU, et al. Evolving importance of kidney disease: from subspecialty to global health burden. Fink HA, et al. Screening for, monitoring, and treatment of chronic kidney disease stages 1 to 3: a systematic review for the U. Ann Intern Med. Goff DC Jr, et al. Ix JH, et al. Equations to estimate creatinine excretion rate: the CKD epidemiology collaboration.

Clin J Am Soc Nephrol. James PA, et al. JAMA ;— Katsiki N, et al. Ezetimibe therapy for dyslipidemia: an update. Curr Pharm Des. Levey AS, et al. Kidney Int. Levey AS, Coresh J. Chronic kidney disease. GFR estimation: from physiology to public health. Am J Kidney Dis. Macgregor MS, Methven S. Assessing kidney function. In: Daugirdas JT, ed. Hand- book of Chronic Kidney Disease Management. Philadelphia, PA: Wolters Kluwer; — KDOQI clinical practice guidelines for bone me- tabolism and disease in chronic kidney disease.

Proteinuria: does vitamin D treatment improve outcomes in CKD? Nat Rev Nephrol. The effect of antihypertensive drugs on chronic kidney disease: a comprehensive review. Hypertens Res. Sharp Collaborative Group. Study of Heart and Renal Protection SHARP : randomized trial to assess the effects of lowering low-density lipoprotein cholesterol among 9, patients with chronic kidney disease. Am Heart J. Stone NJ, et al. Ide- ally, the patient should also be a part of a multidisciplinary predialy- sis program that includes patient and family education, early choice of appropriate renal replacement modality, and, if dialysis is being considered, elective creation of dialysis access.

The advantage of a programmatic approach to care is a planned outpatient initiation of dialysis in a patient who is both mentally and physically prepared. It is likely that this approach results in fewer hospital days in the first month after beginning dialysis and substantial cost savings. Patient education. Of key importance is patient education about the various treatment options available in the event that renal replacement therapy will become necessary.

Would the patient best benefit from some form of dialysis, from preemp- tive transplantation, or from continued conservative manage- ment? In some cases, due to extreme patient debility or other reasons, dialysis may not be an appropriate option, and con- servative management may be the best choice.

These discus- sions are best initiated once a patient is still in stage 4 CKD, and well before stage 5 has been reached. Options for renal replacement therapy Table 2. Preemptive transplantation. Transplantation offers survival superior to the standard forms of dialysis being offered today. Transplantation may not be indicated, however, for a patient who has severe problems with compliance in terms of medications.

Preemptive Live or cadaver Improved patient Logistics of transplantation donor transplant survival relative to finding a suitable before ever conventional dialysis; donor; need for needing dialysis lower long-term costs. Home 3—6 times per When given more than Home is changed hemodialysis week, either 3 times per week, or into a hospital; during the day when given as 8—hour partner burnout; or at night.

Dialysis time staff assisted or spent sleeping self-care In-center Either staff Short amount of time Travel to unit; conventional assisted the spent on dialysis. Staff relatively inflexible hemodialysis norm or does all the work schedule. May be self-care inadequate amount of dialysis Postponing Very-low- May work to postpone Expense of dialysis protein diet plus dialysis for about 1 year ketoanalogues ketoanalogues, in elderly patients with careful fluid few comorbidities no management heart failure, diabetes.

Palliative care Conservative Good for those patients Potentially reduced management for whom dialysis is not life expectancy without dialysis expected to prolong life to a significant extent or in whom overwhelming comorbidities are present Modified from Tattersall JE, Daugirdas JT. Preparing for dialysis. Dialysis: Home versus in-center therapy. Among the end-stage renal disease ESRD therapies, the choices made will de- pend on what is available in the local community. One of the main decisions to be made is whether the patient will be coming in to a clinic for regular dialysis hemodialysis in this case , or whether he or she would prefer the inde- pendence of dialyzing at home, using either a home he- modialysis system or peritoneal dialysis PD.

In observational studies, mortality rates are lower in home hemodialysis patients than in in-center hemodi- alysis patients, sometimes dramatically so, even after ad- justments for common comorbidities and at similar total weekly dialysis times. Mortality rates for in-center hemodialysis are sim- ilar to those for home PD, so the selection of home versus in-center modality should be based primarily on patient preferences versus any anticipated survival benefit.

Normally, whether done at home or in-center, hemodialysis therapy is offered 3 times per week, usually 3—5 hours per session. When the same amount of dialysis time is broken up into five or six sessions per week, some observational studies have shown better control of blood pressure, better nutrition weight gain, increased appetite and albumin , and better control of anemia.

In the only moderate-sized randomized trial that has been. There was no improvement in serum albumin, nutritional mea- surements, or control of anemia FHN Trial Group, Usually frequent hemodialysis is done at home and is only rarely offered in-center or in self- care units. Long nocturnal hemodialysis. With nocturnal dialysis, substantially longer weekly dialysis times are the norm, because each session typically lasts for 7—9 hours.

When nocturnal dialysis is given in-center, the usual frequency is 3 times per week, and the weekly di- alysis time will be 24 hours per week compared to the usual 12 hours per week with conventional schedules.

When ap- plied at home, nocturnal dialysis can be given 3 times per week, every other night, or even 5 to 6 times per week, re- sulting in markedly more hours per week of treatment than conventional therapy. Long nocturnal dialysis is discussed in more detail in Chapter Peritoneal dialysis.

Due to its simplicity, PD offers patients a home-based therapy with very little requirement for special water systems and simple equipment setup time. There are two types of PD for a patient to consider: continuous ambulatory peritoneal dialysis CAPD , where a patient performs manual exchanges 4 or 5 times per day, and auto- mated peritoneal dialysis APD , where a patient hooks up to a machine at night and exchanges are carried out auto- matically while the patient sleeps.

The relative benefits of each type of PD are discussed more fully in the PD chapters of this handbook. Patients for whom PD is often favored include: 1.

Infants or very young children 2. Patients with severe cardiovascular disease 3. Patients with difficult vascular access e. Patients who desire greater freedom to travel 5. Patients who wish to perform home dialysis but do not have a suitable partner to assist them. Contraindications include an unsuitable peritoneum due to the presence of adhesions, fibrosis, or malignancy. Also, a substantial number of patients experience an in- crease in their peritoneal membrane transport rate over time, resulting in inadequate ultrafiltration.

A major cause of abandonment of PD is the occurrence of frequent episodes of peritonitis. Patient burnout is also a factor. PD is less expensive than hemodialysis, particularly in developing countries. Also, it allows patients independence and freedom to travel and does not constrain patients to a fixed in-center hemodialysis schedule, although a more flexible schedule is also possible with home hemodialysis.

Some patients also enjoy the socialization that occurs in many hemodialysis units, and enjoy the regular personal interaction with staff and other patients.

There have been a number of improvements in PD over the past several years, including better disconnect systems, resulting in decreased peritonitis rates. Also, with use of APD, there can be improved clearances. New PD so- lutions have become available, including glucose-based solutions with decreased amounts of glucose degradation products, as well as solutions using amino acids or icodex- trin as the osmotic agent. Postponing dialysis.

In some patients, particularly the elderly, who do not have marked problems with fluid overload, the need for dialysis can be postponed by prescribing a very- low-protein diet supplemented with ketoacids Brunori, In carefully selected elderly patients assigned to this strategy, the need for dialysis was postponed on average by 1 year. The option not to dialyze: Palliative care.

There are no absolute contraindications to dialysis therapy. In some states, le- gal precedent exists guaranteeing dialysis to anyone who desires it despite the severity of other medical problems. When a patient is unable to voice his or her own thoughts and when the family has divided opinions about the desir- ability of initiation of life support by dialysis, the hospital ethics committee may be of assistance. The U. Renal Physicians Association has issued a clinical practice guideline for stopping or never beginning dialysis in certain patients Renal Physicians Association,.

The guidelines emphasize shared decision making, informed consent or refusal, esti- mating prognosis, and a time-limited trial of dialysis where indicated. The adult recommendations are summarized in Table 2. Patients with advanced disease in an organ sys- tem other than the kidneys, or those with malignancy, have sometimes been excluded from chronic dialysis. For exam- ple, those with advanced liver disease might have ascites, encephalopathy, bleeding diathesis, and hypotension.

These concomitant problems may make access difficult, and the dialysis treatments may create too much hypotension or fail to correct the accompanying fluid overload. In some such patients, dialysis may be futile. Futility is an ethical principle on which one can make a reasonable decision not to initiate dialysis. Elderly patients and dialysis. Access placement in this group is not particularly difficult, and cuffed venous. Develop a physician—patient relationship for shared decision making 2.

Institute advance care planning 5. Consider a time-limited trial of dialysis for patients requiring dialysis, but who have an uncertain prognosis, or for whom a consensus cannot be reached about providing dialysis 8.

Establish a systematic due process approach for conflict resolution if there is disagreement about what decision should be made with regard to dialysis 9. Use a systematic approach to communicate about diagnosis, prognosis, treatment options, and goals of care.

Time constraints are not a problem, and these individuals often ar- rive eager for their treatments. Transportation often is available from assisted-living providers, retirement community staff, or municipal programs.

A high rate of compliance with all aspects of treatment often offsets a higher prevalence of comorbid car- diac, vascular, malignancies conditions in achieving a good outcome. As a result, many elderly patients placed on dialysis continue to enjoy a good quality-of-life and benefit from docu- mented improvement in a variety of health outcome measures.

Adolescents on dialysis. There may be significant problems af- fecting adolescents on hemodialysis or PD. Issues include de- pression and frustration with medical orders, interpersonal conflicts with family members, poor attendance at school due to frequent hospital admissions, and peer pressure because of inability to participate in school sports.

This may manifest as a flat affect limited social interactions and evasion of com- munication and nonadherence to medications, diet, and missed clinic visits. Psychological support and social worker input are key. For hemodialysis, the pre- ferred access is an arteriovenous AV fistula.

It is important that for all patients for whom renal replacement therapy is antici- pated, the veins in both arms should be preserved to the greatest extent possible. All venipunctures should be drawn from the back of the hand where possible. The use of PICC percutaneous in- travenous central catheter lines should be avoided to the great- est extent possible, as these often result in future access outflow problems. Because some patients have veins that are fragile, cre- ating an access early is important; i.

A lead time of at least 6 months prior to anticipated dialysis may allow correction of suboptimal flow or placement of a second fistula in the event that the initial fistula does not function properly.

Vascular access issues are discussed in detail in several chapters of this handbook. For PD, a peritoneal catheter should be in place at least 2 weeks prior to the anticipated start of dialysis. In the past, an AV fistula was recommended as a fallback option for patients who choose PD. This is no longer recommended but is practiced in some centers. In situations where urgent start of dialysis is needed, a recent trend is to place a peritoneal catheter, which then allows initial control of uremia by PD, and buys time for sub- sequent placement of an AV fistula.

Uremic syndrome. The uremic syndrome consists of symptoms and signs that result from toxic effects of elevated levels of ni- trogenous and other wastes in the blood. Uremic patients commonly become nauseated and often vomit soon after awakening. They may lose their. Their mental status is altered; at first, only subtle changes in per- sonality may appear, but eventually, the patients become confused and, ultimately, comatose.

Signs of uremia in the modern age are less com- mon, because patients now come to medical attention at a relatively early stage of uremia. Nevertheless, sometimes uremic patients presenting with a pericardial friction rub or evidence of pericardial effusion with or without tam- ponade may reflect uremic pericarditis, a condition that urgently requires dialysis treatment.

Foot- or wrist-drop may be evidence of uremic motor neuropathy, a condition that also responds to dialysis. Tremor, asterixis, multifocal myoclonus, or seizures are signs of uremic encephalopa- thy. Prolongation of the bleeding time occurs and can be a problem in the patient requiring surgery.

Signs and symptoms: Uremia versus anemia. Several of the symp- toms and signs previously ascribed exclusively to uremia may be partially due to the associated anemia.

When the anemia of anemic CKD patients is improved with erythro- poietin, they often experience a marked decrease in fatigue and a concomitant increase in sense of well-being and ex- ercise tolerance. The bleeding time may also improve, and there may be improvement in angina pectoris. There are improvements in cognitive function as well. Relationship between uremic syndrome and eGFR.

Indications for dialysis in the chronic setting. Patients with heart failure and borderline eGFRs may have trouble with refractory fluid retention and may require earlier initiation of dialysis. Conditions that may argue for relatively early initiation of di- alysis are listed in Table 2. Neurologic dysfunction e.

It should be noted that pericarditis or pleuritis without other cause is an indication for urgent dialysis, particularly pericarditis, where the risk of rapidly developing pericardial effusion and cardiac tamponade is present.

Neurologic dys- function, especially signs of encephalopathy manifested by asterixis or uremic neuropathy, is also cause for prompt dialy- sis, as is prolongation of the bleeding time, which could lead to gastrointestinal or other bleeding. Most of these urgent indica- tions are found in patients who appear with acute on chronic renal failure. Additional issues pertaining to acute dialysis are discussed in Chapters 10 and References and Suggested Readings Brunori G, et al.

Efficacy and safety of a very-low-protein diet when postponing dialysis in the elderly: a prospective randomized multicenter controlled study. Cooper BA, et al. N Engl J Med. Renal replacement therapy should be tailored to the patient. FHN Trial Group. In-center hemodialysis six times per week versus three times per week. Iyasere O, Brown EA. Determinants of quality of life in advanced kidney disease: time to screen?

Postgrad Med J. Kallab S, et al. Indications for and barriers to preemptive kidney transplantation: a review. Transplant Proc.

Kupin WR. Pre-emptive kidney transplantation. Lo WK, et al. Preparing patients for peritoneal dialysis. Perit Dial Int. Low J, et al. The experiences of close persons caring for people with chronic kidney disease stage 5 on conservative kidney management: contested discourses of age- ing.

Health London. Luckett T, et al. Advance care planning for adults with CKD: a systematic integrative review. Mehrotra R, et al. Patient education and access of ESRD patients to renal replacement therapies beyond in-center hemodialysis.

Renal Physicians Association. Shih YC, et al. Impact of initial dialysis modality and modality switches on Medicare expenditures of end-stage renal disease patients. Song MK, et al. Res Nurs Health. Traynor JP, et al. Early initiation of dialysis fails to prolong survival in patients with end-stage renal failure.

J Am Soc Nephrol. Dialysis is a process whereby the solute composition of a solution, A, is altered by exposing solution A to a second solution, B, through a semipermeable membrane. Conceptually, one can view the semi- permeable membrane as a sheet perforated by holes or pores. Water molecules and low-molecular-weight solutes in the two solutions can pass through the membrane pores and intermingle, but larger sol- utes such as proteins cannot pass through the semipermeable bar- rier, and the quantities of high-molecular-weight solutes on either side of the membrane will remain unchanged.

Solutes that can pass through the membrane pores are transported by two different mecha- nisms: diffusion and ultrafiltration convection. The movement of solutes by diffusion is the result of random molecular motion.

The larger the molecular weight of a solute, the slower will be its rate of transport across a semipermeable membrane. Small molecules, moving about at high velocity, will collide with the membrane often, and their rate of diffusive transport through the membrane will be high.

Large molecules, even those that can fit easily through the membrane pores, will diffuse through the membrane slowly because they will be moving about at low velocity and collid- ing with the membrane infrequently Fig.

The second mechanism of solute transport across semipermeable membranes is ultrafiltration convec- tive transport. Water molecules are extremely small and can pass through all semipermeable membranes. Ultrafiltration occurs when water driven by either a hydrostatic or an osmotic force is pushed through the membrane Fig. The water being pushed through the membrane is accompa- nied by such solutes at close to their original concentrations.

Analogous processes are wind sweeping along leaves and dust as it blows and current in the ocean moving both small and large fish as it flows. Larger solutes, especially those that are. Membrane A B A B. As shown, in both processes, low-molecular-weight solutes can cross the semipermeable membrane, whereas larger solutes are held back. For such large solutes, the membrane acts as a sieve.