It is estimated that 3 million Americans will have chronic renal failure by the year 2008. Diabetes and hypertension account for two thirds of persons with chronic renal failure. Other high-risk patients include those with chronic glomerulonephritis or a family history of renal disease. High-risk patients should be screened with quarterly blood pressure measurements, and annual urinalysis, serum creatinine and 24-hour urinary microalbumin measurements. McCarthy reviewed the literature on managing chronic renal failure and developed a helpful mnemonic, “BEANS,” to help physicians remember the steps that should be taken in at-risk patients to slow the progression of renal disease.
Blood Pressure Control. Blood pressure should be reduced to 130/85 mm Hg in patients with renal disease. The blood pressure should be no more than 125/80 mm Hg in patients who have more than 3 g per day of protein in their urine. Angiotensin-converting enzyme inhibitors are the preferred anti-hypertensive therapy in patients without hyperkalemia and serum creatinine levels of less than 3 mg per dL (265 mmol per L). Nondihydropyridine calcium channel blockers may also help to slow the progression of kidney disease.
Erythropoietin. Patients with chronic anemia related to renal failure should be treated when their hemoglobin level reaches 10 g per dL (100 g per L), with a hematocrit less than 30 percent, to improve function and cardiac problems. Treatment includes 200 mg per day of elemental iron and 1 mg per day of folic acid. If this treatment does not raise the hemoglobin level to 10 g per dL, patients should be treated with 40 to 60 U per kg of subcutaneous erythropoietin one or two times per week. This dosage should be increased 25 percent if the targeted hemoglobin level is not reached in four weeks. Some patients have a rapid response to erythropoietin; therefore, renal function must be monitored monthly, and iron studies must be checked quarterly to detect hypertension and hyperkalemia.
Access for Long-Term Dialysis. Placement of long-term hemodialysis access when the serum creatinine level reaches 4 mg per dL (350 mmol per L) and the glomerular filtration rate is less than 20 mL per min improves survival and decreases hospitalization and complication rates. Furthermore, it increases the chance that the patient will be a candidate for peritoneal or home dialysis.
Nutritional Care. The need to obtain optimal nutrition in the anorexic patient must be balanced with the need to restrict protein, sodium, potassium and phosphorus intake. Poor outcomes are associated with an albumin level less than 3 g per dL (30 g per L). Patients who are 5 to 10 percent below ideal body weight, who eat less than 30 kcal per kg per day or who spontaneously eat less than 0.8 g per kg per day are at risk of muscle wasting. Once patients are on dialysis, their protein restriction can be liberalized to 1 to 2 g per kg per day. Bicarbonate should be supplemented when the serum bicarbonate level is below 20 mEq per L. Patients should receive vitamin B and folic acid supplements, and water-soluble vitamins. Supplements with vitamin A, vitamin D2 and vitamin C should not be given. Phosphorus levels should be maintained at 3.5 to 5 mg per dL (1.13 to 1.61 mmol per L) with dietary restriction and phosphate-binding calcium salts at meal times.
Specialist Referral. Guidelines for referral include a glomerular filtration rate less than 30 mL per min per 1.73 m2 (serum creatinine level of 3 mg per dL) or an anticipated need for dialysis within a year. A patient who is a candidate for a renal transplant should also be referred.