Case Study: Chronic Kidney Disease

Transcription

1 Taylor Zwimpfer Joan Rupp Nutrition September 2014 Case Study: Chronic Kidney Disease 1. Kidneys act to maintain the balance of fluids, electrolytes and organic solutes in the body through filtration of blood and fluid. After reabsorbing and secreting the fluid, ultrafiltrate is produced to contribute to urine excreted. The kidney regulates water homeostasis as well. By the time all liquid has been filtered by the kidneys, mostly nitrogenous compounds remain including urea, uric acid, creatinine and ammonia. Excretion of these waste products by the kidneys is known as renal function. Blood pressure is majorly controlled by the kidney and the renninangiotensin mechanism. Erythropoietin is a hormone produced by the kidney as well, deficiency of this hormone causes anemia present in chronic renal disease. The kidney produces the active form of Vitamin D and aids in elimination of calcium and phosphorus. In turn, active Vitamin D promotes absorption of calcium in the gut which is necessary for healthy bones. 2. Chronic Kidney disease can be caused by high blood pressure, ageing kidneys, kidney stones, acute kidney injury,glomerulonephritis, hypertension and diabetes. When one half to two thirds of kidney function is lost, it is inevitable for the remaining kidney to fail, regardless of the related disease. Diabetes is the number one risk factor for CKD, followed by hypertension. Blood vessels in the kidneys are harmed/damaged during diabetes which prevents proper functionality. This results in the blood not being filtered or cleaned efficiently and protein and wastes accumulate. Blood protein albumin leaks into the urine, causing further destruction that eventually leads to the 5 stages of CKD and eventually renal failure. 3. There are 5 stages of CKD. Stages 1 and 2 are characterized by markers like proteinurea, hematuria, and anatomic issues. In stage 1 the egfr is between ml/min, some kidney damage is present but there is normal to increased kidney function. Stage 2, egfr is 60-89mL/min with a mild decrease in kidney function. Stages 3 and 4 are advanced stages with stage 3 at 30-59mL/min and stage 4 at 15-29mL/min. During these stages we see movement from moderate to severe decrease in kidney function. At stage 5, defined as end stage renal failure, death will result unless dialysis or transplantation occurs with an egfr of less than 15mL/min.

2 5. At stage 5 of CKD treatment options include dialysis, transplantation or medical management progressing to death. Patients have the option to choose between hemodialysis or peritoneal dialysis. Hemodialysis occurs using a fluid and electrolyte content similar to normal plasma were products move by diffusion, ultrafiltration and osmosis. Treatment is usually 3 to 5 hours, three times a week. In peritoneal dialysis the body s peritoneum, a semipermeable membrane is used and a catheter is surgically implanted in the abdomen and into the peritoneal cavity. Diasylate with a high dextrose solution is placed in the peritoneum. Extra fluid and waste are drawn into the diasylate and out of your blood. The fluid is then drawn and discarded and new fluid is added. This process is continuous. 6. Nutrition Therapy Rationale 35 kcal/kg Energy intake should be at this level for adults to spare protein for tissue repair and maintenance. 1.2g protein/kg Protein intake in CKD patients should be between g/kg/day. This helps increase serum albumin, protect protein malnutrition and decrease proteinuria. Too much protein increase glomerular pressure and thus leads to renal dysfunction. 2 g K The adequate amount of potassium for an average adult is mg. The recommendation of 2g is made to keep the potassium intake normal. Potassium wasting diuretics require supplementation of potassium but when urine output decreases to below 1L/day potassium restriction may be necessary as kidneys have difficulty excreting it. 1 g phosphorus Normal adults should have a diet modified to not allow more than 1000mg phosphorus per day as serum phosphorus levels elevate at the same as egfr levels decrease. Maintaining phosphorus levels helps to avoid hyperparathyroidism and hyperphosphatemia. 2g Na Dietary intake of sodium should be between 2-3g in order to control edema and avoid total body sodium overload as the body of circulating blood may be reduced due to the deterioration of renal function ml fluid + urine In patients with CKD, fluid should be equal urine output plus 1 output to 1.5L/day of fluid to account for insensible losses. This ensures there is not a sodium/water imbalance. 7. At age 24, 5 0 and a weight of 170lbs, Mrs. Joaquin s BMI is 33.2 (obese). Edema would cause fluid retention/swelling that could likely be increasing her weight and thus her BMI might be higher than what it actually is.

3 8. Edema free weight is the weight of your body without excess body fluid built up from dialysis treatment. It is calculated using this equation: abw ef = BW ef + [(SBW BW ef ) x 0.25] abwef= 165+[(65-165) x 0.25]= 140lbs where BW ef is the actual edema-free body weight and SBW is the standard body weight as determined from the NHANES II data. Mrs. Joaquin s edema free body weight is 140 lbs. 12. Because protein needs are higher in patients with CKD, those on hemodialysis should maintain 1.2 g/kg body weight whereas those who are on peritoneal dialysis should consume g/kg body weight each day. Regardless of the type of dialysis, 50-60% should come from sources with a high biological value. Pre-dialysis protein intake can range anywhere from 0.8 mg-1.5g/kg/day. Numbers are lowered during dialysis to avoid an increase in glomerular pressure from dietary protein but is also maintained to avoid protein malnutrition. A balance is necessary so there is no further renal failure. 13. In CKD, hyperphosphatemia and hyperparathyroidism can be delayed by reducing or maintaining the correct amounts of phosphorus in the body. A dietary restriction is necessary for those on dialysis so that excess phosphorus does not end up in the blood or urine. Phosphorus is limited in Mrs. Joaquin to 1g/day which is approximately 1-2 dairy foods where it is found the highest. Phosphorus is also found in high levels in liver, pork, veal, cod, sardines with bones, tuna, milk/milk products, lentils, and beans. 14. Fluid consumption and recommended levels are based individually on the patient, taking into consideration the type of dialysis they are one, their urinary output, blood pressure, weight gain or loss, edema, and heart difficulty. Foods considered to be fluids include: soup, ice cream, popsicles, custard, gelatin, and certain fruits (watermelon), yogurt. Recommendations would include limiting salty food intake to decrease thirst, drink only when thirsty from small cups, pills should be taken with mealtime liquids such as applesauce, chewing gum may help maintain moisture in the mouth, and sucking on ice cubes can help to eliminate dry mouth but maintain fluid intake. Eating frozen grapes, blueberries, pineapples may help to eliminate thirst as well. 15. GFR measures the rate at which blood passes through the glomeruli each minute. A normal GFR ranges from mL/min. Mrs. Joaquin s GFR is 28mL/min, this is a sign of kidney failure and sever decrease in kidney function as characterized by stage 4 CKD. 16. Mrs. Joaquin lab values exemplify each of the following indication stage 5 CKD: -low sodium levels due to loss in urine or fluid retention as a result of dialysis

4 -high serum potassium, phosphate, blood urea nitrogen, creatinine indicating compromised filtration in kidneys -low serum Calcium indicates insufficient vitamin D as it is converted to its active form in the kidneys -low CO2 indicated compromised acid base balance, malnutrition - high blood glucose associated with diabetes -high cholesterol and triglycerides due to inflammation of the glomerulus causing altered lipid metabolism 18. -protein urine indicates losses due to renal disease progression -HbA1C is elevated likely due to uncontrolled hyperglycemia and diabetes causing CKD Medication Indications/Mechanism Nutritional Concerns Capoten/ captopril Treats high BP to decrease kidney problems, relaxes blood vessels so blood can flow freely Erythropoietin Sodium bicarbonate Renal caps Renvela Hectorol Glucophage Replaces the hormone produced by the kidneys to stimulate production of RBCs by bone marrow Control acidity of blood and urine Combination of B vitamins in order to prevent deficiency Lowers blood phosphorus levels in patients on dialysis Used for secondary hyperparathyroidism with CKD In type 2 diabetes, glucophage helps control the amount of glucose in the blood by decreasing the amount absorbed from food and made May increase potassium levels, cause N/V/D leading to dehydration May cause n/v/d. Necessary to supplement iron, B12 and folate and compliance to ESRD diet Causes an increase of sodium in the body so low sodium foods should be consumed. Could cause an increase in thirst and water retention May interfere with lab tests (folic acid may mask symptoms of pernicious anemia) Competes with other drugs for absorption in the stomach May cause edema, N/V, hypercalcemia, hypercalciuria May cause a loss of appetite and decreases folate and vit B12 absorption.

5 in the liver, increases response to insulin 19. The Pima Indians have been found to have the highest rate of incidence of diabetes. Scientists use the thrifty gene theory to describe why the Pima are overweight. In this theory populations in times of famine were able to store up fat during food shortages if they possessed this gene. Because famine is unlikely in modern times, those who possess this gene are at a greater risk for being overweight. The Pima Indians alternated between periods of feast and famine so their bodies learned to maintain fat during times of plenty so that when famine came they could survive. With time however, the Pima Indians have become less physically active and have maintained a constant food supply so the gene that they developed for protection is no longer necessary. This gene has predisposed them to many chronic diseases, especially diabetes and kidney disease. Research has shown that diabetes begins at a much younger age in the Pima than in other populations, thus exposing them to more time to obtain other chronic conditions throughout their lifetime. 22. Foods containing all essential amino acids are considered to have a high biological value. It is crucial for at least 50% of the protein sources that Mrs. Joaquin is consuming to have a high biological value because that way the right amounts/ratios of different amino acids are entering the body and being used more efficiently to produce less waste. The less waste in the body there is, the less of a struggle the kidneys have in filtering it out. If there are too many of certain amino acids, the body will attempt to discard them, thus creating more work for the kidneys.