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1 NUR409 Chronic Renal Failure -progressive, irreversible destruction of both kidneys; continues until many nephrons are destroyed and replaced by nonfunctional scar tissue.-end result involves every body system-up to 80% of GFR (glomerular filtration rate) capacity may be lost with very few changes in the functioning of the body -often, people do not realize the extent of the renal damage because the remaining nephrons hypertrophy in order to compensate. -CRF can be divided into three stages: 1. diminished renal reserve: normal BUN and creatinine levels and an absence of symptoms 2. chronic renal insufficiency (CRI): GFR is about 25% of normal. BUN and creatinine levels are increased. Common symptoms include easy fatigue and weakness. As the renal failure progresses, headaches, nausea, and pruritis may occur. Nocturia and polyuria occur as a result of the kidney's inability to concentrate urine. 3. End Stage Renal Disease(ESRD): The last stage occurs when GFR is less than 5% to 10% of normal. -Each year 30,000 die from various diseases of the kidney. -In 1973, the federal government enacted a law that provided financial assistance through Medicare for all eligible persons who had ESRD and required treatment. The majority of ESRD patients (>160,000) are treated with dialysis because: 1) not enough organs 2) many patients do not want transplants 3) patients are too medically unstable. Because of the End-Stage Renal Disease Medicare Program in the United States, almost every patient, regardless of age, is offered dialysis. As the population ages, diabetes and HTN are the leading causes of CRF in the United States. Clinical Manifestations-Clinical manifestations are d/t retained substances ie. urea, creatinine, hormones, abnormal electrolytes. During the stage of renal insufficiency, polyuria (reflects a lack of concentrating ability). This progresses to oliguria and anuria. BUN and creatinine levels increase. As BUN increases, nausea, lethargy, fatigue, vomiting, diarrhea, and headaches become common complaints. Initial treatment is protein restriction. Altered CHO metabolism: individuals with impaired renal function become resistant to insulin. Moderate hyperglycemia, hyperinsulinemia, and abnormal glucose tolerance tests are common findings. May become normalized once dialysis is initiated. The insulin doses of IDDM patients must be closely monitored. Most patients with uremia develop hyperlipidemia. The hyperinsulinemia stimulates liver production of triglycerides and the absorption of triglycerides by peripheral tissues is reduced. This problem worsens the situation for the diabetic patient with renal disease who already has atherosclerotic changes. Hyperkalemia Calcium and phosphate concerns metabolic acidosis: results from the impaired ability of the kidneys to excrete the acid load (primarily ammonia) and from defective reabsorption and regeneration of bicarbonate. The average adult produces 80 to 90 mEq of acid a day. Plasma bicarbonate usually keeps this acid load in a steady state. anemia: results from decreased production of erythropoietin. Also, many patients with renal failure are iron deficient. Folic acid is dialyzable. The hemodialysis machine can cause hemolysis. Bleeding tendencies: Defects in platelet function and the coagulation system d/t uremia infection: changes in leukocyte function and altered immune response and function. cardiovascular abnormalities: Most common is hypertension usually caused by sodium retention and fluid volume increases. For some people, there is also an increase in renin. May see uremic pericarditis. May see CAD. respiratory system changes: Kussmaul's respirations (seen more with ARF but may see with CRF), uremic pneumonitis often found which is interstitial edema d/t uremia. GI alterations: Mucosal inflammation d/t urea. May see ulcerations. Constipation is a frequent complication of calcium-containing phosphate binders (or Aluminum-based—although these are not used as often), which are 2 taken to facilitate phosphate excretion. People may experience metallic taste in the mouth, urinous odor of the breath, nausea, anorexia, vomiting. Neurologic system: general depression of the CNS. Peripheral neuropathy with c/o restless leg syndrome (bugs crawling around on the inside of the leg-may cause a bring problem with sleep disturbances). Paresthesias, muscle twitching, and nocturnal leg cramping. Musculoskeletal system changes: develop renal osteodystrophy, which is a syndrome of skeletal changes resulting from alterations in calcium and phosphate metabolism. Patient develops osteomalacia & metastatic calcifications. Skin: yellow discoloration, dry, pale. Uremic frost is a condition in which urea crystallizes on the skin and is usually only seen with the BUN levels are extremely high. Reproductive system: Infertility and decreased libido. Endocrine: All patients with CRF exhibit some clinical manifestations of hypothyroidism. psychological changes Treatment -Initially try conservative management. First attempt to detect and treat potentially reversible causes of renal failure. Try to preserve existing kidney functioning and treat symptoms. Use pharmacologic, nutritional management and supportive care. -Treat hyperkalemia, hypertension, renal osteodystrophy (restrict phosphate intake and give aluminum hydroxide to bind with phosphate so that it is excreted in the stool. Calcium-based phosphate binders are being used more frequently because dementia is associated with excessive absorption of aluminum). -Do not give magnesium-based products because Mg is excreted by the kidneys. -If hypocalcemia is a problem, can give active Vitamin D products. -Use erythropoiten. -Watch patients closely with medication therapy as many meds are excreted by the kidneys. Digitalis preparations are excreted by the kidney but are not dialyzed out. Dialysis does reduce potassium levels. -Never administer meperidine (Demerol). (liver metabolizes it to normeperidine which is excreted by the kidneys. If it accumulates, may cause seizures.) -Restrict protein intake. -Water restriction. Generally allow 500 to 600 ml/ day plus urine output. Once people start on hemodialysis, fluid intake is adjusted so that the patient gains no more than 1 to 1.5 kg between treatments. -Sodium and potassium restrictions Planning -Overall goals are for a patient with CRF to demonstrate knowledge and ability to comply with therapeutic regimen; participate in decision making for the plan of care and future treatment modality; demonstrate effective coping strategies; continue with ADLs. -Once conservative management is no longer enough, dialysis or transplantation are the only measures available to prolong the patient's life. DIALYSIS-Movement of fluid and molecules across a semipermeable membrane from one compartment to another. Substances are moved from the blood to the dialysate. -Correct fluid and electrolyte balances and remove waste products. -Can also be used to treat drug overdoses assuming that the drug is dialyzable. -Two types of dialysis: 1) peritoneal 2) hemodialysis -Principles of diffusion, osmosis, and ultrafiltration are involved in dialysis. a. diffusion: movement of solutes from an area of greater concentration to an area of lesser concentration. In renal failure, urea, creatinine, uric acid, potassium and phosphate move by diffusion. b. osmosis: movement of fluid from an area of lesser to an area of greater concentration of solutes. Glucose is added to the dialysate and creates an osmotic gradient. 3 c. ultrafiltration: water and fluid removal A. Peritoneal Dialysis -In the US, approximately 13% ESRD patients are on PD -In Canada, greater number are on PD because of the lack of availability of HD -Catheter Placement: Peritoneal access is obtained by inserting a catheter through the anterior abdominal wall. The prototype of the catheter was developed by Tenckhoff in 1968 and is made by silicone rubber tubing. The current version is about 25 cm long and has one or two Dacron cuffs at the subcutaneous and peritoneal ends of the catheter that anchor it securely and prevent the migration of microorganisms down the shaft from the skin. Within a few weeks, fibrous tissue grows into the Dacron cuff, anchors the catheter in place, and prevents bacterial penetration into the peritoneal cavity. -Variety of techniques for inserting the catheter. Typically, the patient goes to the OR. -Before PD is started, usually a waiting period of 7-14 days to allow the catheter to seal. -Once the catheter incision site is healed, the patient may shower and then pat the catheter and exit site dry. Daily antiseptic solution is applied with a sterile dressing. Additionally, patients need to assess the catheter site for signs of infection. -Dialysis Solution: Available in 1 or 2 liter bags with glucose concentrations of 1.5%, 2.5% and 4.25%. Electrolyte composition is similar to plasma without potassium. Dialysate solution should be warmed. Ultrafiltration depends upon the concentration of the dialysate solution. -Phases of PD cycle: inflow (fill), dwell (equilibration), drain. These three phases make up an exchange. Patient with home PD will receive about four exchanges per day. Usually use 2 liters infused over about 10 minutes. After the solution is infused, the tubing is clamped. Duration of the dwell time can range from 20 to 30 minutes to 8 or more hours. -Two types of PD: 1). Automated peritoneal dialysis: uses cycler equipment to deliver the dialysate for APD. 2). Continuous ambulatory peritoneal dialysis: carried out manually by exchanging four times daily with dwell times of 4 to 10 hours. Critical to maintain aseptic technique. CONTRAINDICATIONS FOR PD: 1. HISTORY OF MULTIPLE ABDOMINAL SURGICAL PROCEDURES OR SEVERE PATHOLOGY 2. RECURRENT ABDOMINAL WALL OR INGUINAL HERNIAS 3. EXCESSIVE OBESITY WITH LARGE ABDOMINAL WALL AND FAT DEPOSITS 4. PREEXISTING VERTEBRAL DISEASE 5. SEVERE COPD Complications of PD: 1. exit site infection 2. peritonitis (cloudy peritoneal effluent that has a WBC count of over 100 cells per microliter 3. abdominal pain 4. outflow problems (after the catheter has settled into place, bowel evacuation usually relieves this problem) 5. lower back problems 6. bleeding 7. pulmonary complications 8. protein loss: protein substances can move through the peritoneal membrane. Patient needs adequate protein intake to maintain a positive nitrogen balance 9. CHO and lipid abnormalities: glucose is absorbed which increases insulin secretion which stimulates liver production of triglycerides 4 B. Hemodialysis -First initiated in the US in 1950s -Vascular access sites are one of the biggest challenges. -Need a high blood flow for HD -Types of accesses: 1. external cannula or shunt: teflon silicone rubber cannula inserted into the radial artery and into an adjacent forearm vein. Associated with many complications. Not used for chronic HD. 2. internal arteriovenous fistulas and grafts: a. AV fistula: created in the forearm or thigh by an anastomosis between an artery and a vein (usually radial or ulnar artery and cephalic vein). Increased pressure of the arterial blood flow through the vein makes the vein dilate and become tough. The vein is accessed using two large gauge needles. Using the patient's own blood vessels only works if the patient has relatively healthy vessels. Takes 4 to 6 weeks to mature. b. internal AV grafts: use a graft to bridge between the arterial and venous blood supplies. Because grafts are made of manmade materials, they can become infected easily and are thrombogenic. Takes 2 to 4 weeks to heal. Need to assess for thrills, bruits, and avoid BP, IV and venipuncture in the affected extremity. The subcutaneous AV fistula is much less likely to clot and become infected than a graft. When a graft becomes infected - very serious. Often requires removal of the graft. 3. temporary vascular access: Can use subclavian, internal jugular, or femoral vein cannulation with a double lumen catheter. Can be left in place for 1 to 3 weeks. Femoral vein accesses can be left in place for only 1 week. These lines should not be accessed by anyone other than the dialysis team. There is also available a silastic permanent catheter used for permanent or temporary access. Exits the upper chest wall and is tunneled subcutaneously to the internal or external jugular vein. The HD procedure: two needles placed in the fistula or graft. Blood sent to the dialyzer which is primed with saline solution. The saline solution is infused into the patient as blood fills the dialyzer circuit. Heparin is added to the blood as it flows to prevent clotting . Blood is returned from the dialyzer to the patient via the second needle. Nurse needs to closely assess the patient before beginning treatment. Assessment should include fluid status, condition of vascular access, temperature, and general condition of the skin. The difference between the last postdialysis weight and the present predialysis weight determines the ultrafiltration to be removed. Ideally, no more than 1.0 to 1.5 kg should be gained between treatments. HD usually lasts 3 to 4 hours. Complications of HD: 1. disequilibrium syndrome: develops as a result of rapid changes in the composition of the extracellular fluid. Sign/symptoms: nausea, vomiting, confusion, restlessness, headaches, twitching and jerking, and seizures. Due to a high osmotic gradient in the brain causing cerebral edema. (solutes are removed more rapidly from the blood than from the CSF and the brain) May also see muscle cramps and hypotension. Treatment: slow or stop the dialysis, infuse hypertonic saline solution, albumin or mannitol. More commonly seen in the first dialysis treatment when the BUN is high. 2. hypotension: Due to rapid removal of vascular volume. Blood pressure medications may be held before dialysis if there is hypotension during dialysis. 3. muscle cramps: significantly painful and uncomfortable. Due to a rapid removal of sodium and water. 4. loss of blood 5. hepatitis: related to blood transfusions, IV drug abuse, or the lack of adherence to precautions used to prevent the spread of infection. Currently, hepatitis C is responsible for the majority of cases of hepatitis in dialysis patients. 6. Sepsis: often related to infections of the vascular access sites 5 7. increased incidence of cancer. Must remember that individual adaptation to maintenance HD varies from person to person. Dependence on the machine is a reality. Depression and suicidal tendencies may be manifested in noncompliance with diet or drug therapy or in a large weight gain. Continuous Renal Replacement Therapy -alternative method for treating acute renal failure. -provides a means for slowly and continuously removing solutes and fluids in the hemodynamically unstable patient. CRRT very useful in the individual with fluid overload regardless of the cause of the overload. -Several variations of CRRT: One example is continuous arteriovenous hemofiltration. Removes plasma water and nonprotein solutes. The systemic blood pressure provides the force to achieve sufficient blood flow through the hemofilter. This procedure differs from HD: 1. continuous - not intermittent 2. no dialysate is required 3. relies on patient's own blood pressure rather than a pump 4. fewer or no effects on the cardiovascular stability of the patient 5. does not require complicated equipment CAVH can be continued for as long as 30 to 40 days. TRANSPLANTATION -Currently >20,000 people waiting for kidney transplants-Can use living related donors. Usually parents, siblings, or children. Only one donor kidney required. Histocompatibility studies and blood typing are done first. Donor must have a compatible blood type with the recipient and have a similar tissue type to prevent rejection. -Cadaver donors: most commonly trauma victims. Generally accepted age is 5 to 55 years. Donors must be free of systemic disease and infection and must have normal kidney function. A nationwide computerized service is used to distribute cadaveric organs. -For a LRD kidney transplant, need 2 surgical teams. One team carefully removes the donor kidney including the artery, vein and ureter. Donated kidney, whether LRD or cadaveric, is surgically implanted in the iliac fossa because the iliac blood vessels are easy to expose. Donor's ureter is implanted into the recipient's bladder. Bilateral nephrectomies of the recipient's kidneys are not performed unless the patient has uncontrollable hypertension, chronic kidney infections, bleeding in the kidneys. POSTOPERATIVE CARE: -For the LRD: pain of a nephrectomy is greater than that of the iliac fossa incision experienced by the recipient. Most donors ready to be discharged from the hospital in 6 to 7 days and can usually return to work in about a month. -Recipients: Major surgery care. Diuresis generally occurs if the transplanted kidney begins to function. Indwelling catheter used to assess hourly urine output. Catheter is removed ASAP. Assess the abdominal dressing for both urine and blood. Low-grade temperature may be a sign of rejection or infection. Must prevent pulmonary infections. IMMUNOSUPPRESSIVE THERAPY -Used to suppress the body's immune response to the foreign kidney. Standard drugs ordered: 1. Azathioprine (Imuran): causes bone marrow suppression, drug induced hepatitis 2. Corticosteroids: cushingoid syndrome 3. cyclosporine: used to prevent the production and release of interleukin-2 from T-helper lymphocytes which alters the cell-mediated immune attack against the transplanted kidney. Good news is that it does not cause bone marrow depression or alter the normal inflammatory response. This drug is nephrotoxic so levels must be followed carefully. 6 4. Cytoxan can be substituted for the Imuran; however, primarily used to reduce the dose of Imuran if the patient develops hepatotoxicity. Complications of transplantation 1. hyperacute rejection: minutes to hours after transplantation. Renal vessels thrombose and the kidney dies. No treatment and the kidney is removed. 2. acute rejection: usually occurs 4 days to 4 months after transplantation. Mediated by the recipient's Tcytotoxic cells which attack the foreign kidney. Not uncommon to have at least one rejection episode especially with cadaveric-donated kidneys. Signs of rejection: decreasing creatinine clearance, increasing serum creatinine, elevated BUN levels, fever, weight gain, decreased urine output, increasing BP and a swollen ad painful transplant site. 3. chronic rejection: occurs over months or years. Treatment is mainly supportive. 4. infections: respiratory infections are the most frequent cause of death from infection. 5. malignancies: incidence is 100 times greater than that in the general population. 6. chronic liver disease 7. recurrence of renal disease