Section 3 Medical Nutrition Therapy Copyright 2003 Delmar

Section 3 Medical Nutrition Therapy Copyright © 2003 Delmar Learning, a Thomson Learning company

Chapter 19 Diet and Renal Disease Copyright © 2003 Delmar Learning, a Thomson Learning company

Objectives § § Chapter 19 Describe, in general terms, the work of the kidneys. Explain why protein is restricted for renal clients. Explain why sodium and water are sometimes restricted for renal clients. Explain why potassium and phosphorus are sometimes restricted for renal clients. Copyright © 2003 Delmar Learning, a Thomson Learning company 3

Kidneys excrete wastes, maintain volume and composition of body fluids, and secrete certain hormones. They filter the blood, cleanse it of waste products, and recycle other, usable, substances so that the necessary constituents of body fluids are constantly available. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 4

Kidneys One million working parts called nephrons. Glomerulus is the filtering unit. The kidneys maintain both the composition and the volume of body fluids. They maintain fluid balance, acid-base balance and electrolyte balance. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 5

Kidneys Waste materials sent via 2 tubes called ureters from the kidneys to the urinary bladder. 1. 5 liters of urine excreted per day. Waste materials include end products of protein metabolism (urea, uric acid, creatinine, ammonia, and sulfates), excess water and nutrients, dead renal cells, and toxic substances. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 6

Kidneys Oliguria: urinary output less than 500 ml/day. Kidneys unable to adequately eliminate waste products–can result in renal failure. Kidneys indirectly stimulate the bone marrow to produce red blood cells. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 7

Types of Renal Disorders Initially caused by infection, degenerative changes, diabetes mellitus, cardiovascular disorders, cysts, renal stones, trauma. When severe, renal failure may result. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 8

Acute Renal Failure Acute renal failure occurs suddenly and may last a few days to a few weeks. Caused by another medical problem such as a serious burn, a crushing injury, or cardiac arrest. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 9

Chronic Renal Failure Develops slowly, number of functioning nephrons constantly diminishing. Uremia is a condition in which protein wastes that should normally have been excreted are instead circulating in the blood. Symptoms include nausea, headache, coma, convulsions. Severe renal failure will result in death unless dialysis used. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 10

Nephritis Inflammatory diseases of the kidneys. Caused by infection, degenerative processes, or vascular disease. Glomerulonephritis is a nephritis affecting the capillaries in the glomeruli. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 11

Nephrosclerosis Hardening of renal arteries. Caused by arteriosclerosis and hypertension. Usually occurs in older people, sometimes develops in young diabetic clients. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 12

Polycystic Kidney Disease Relatively rare, hereditary disease. Cysts form and press on the kidneys. Kidneys enlarge and lose function. Although people with this condition have normal kidney function for many years, renal failure may develop near the age of 50. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 13

Nephrolithiasis Stones develop in the kidneys. Stones classified according to their composition–calcium oxalate, uric acid, cystine, calcium phosphate, and magnesium ammonium phosphate (known as struvite). Associated with metabolic disturbances and immobilization of the client. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 14

Dietary Treatment of Renal Disease Extremely complicated. Intended to reduce the amount of excretory work demanded of the kidneys while helping them maintain fluid, acid-base, and electrolyte balance. Clients with chronic renal failure may have protein, sodium, potassium and phosphorus restricted. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 15

Dietary Treatment of Renal Disease Sufficient calories necessary: 25 to 50 kcal per kilogram of body weight. Energy requirements should be fulfilled by carbohydrates and fat. Protein increases the amount of nitrogen waste the kidneys must handle. Diet may limit protein to 40 grams based on glomerular filtration rate and weight. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 16

Dietary Treatment of Renal Disease Sodium may be limited if the client tends to retain it. Fluids are typically restricted for renal clients. Calcium supplements may be prescribed. Vitamin D may be added and phosphorus limited, to prevent osteomalacia. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 17

Dietary Treatment of Renal Disease Potassium may be restricted in some clients because hyperkalemia tends to occur in end stage renal disease (ESRD). Excess potassium can cause cardiac arrest. Renal clients often have an increased need for vitamins B, C, and D, and supplements are often given. Iron is commonly prescribed. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 18

Dialysis Done be either hemodialysis or peritoneal dialysis. Hemodialysis requires permanent access to the bloodstream through a fistula. Hemodialysis is done 3 times a week for 35 hours at a time. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 19

Dialysis Peritoneal dialysis makes use of the peritoneal cavity. Less efficient than hemodialysis. Treatments usually last about 10 to 12 hours a day, 3 times a week. Complications include peritonitis, hypotension, weight gain. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 20

Diet During Dialysis clients may need additional protein. Amount must be carefully controlled. A client on hemodialysis requires 1. 0 to 1. 2 g of protein per kilogram of body weight to make up for losses during dialysis. A client on peritoneal dialysis requires 1. 2 to 1. 5 g protein per kilogram body weight. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 21

Diet During Dialysis 75% of this protein should be high biological value (HBV) protein, found in eggs, meat, fish, poultry, milk, and cheese. Potassium is usually restricted. A typical renal diet could be written as “ 80 -3 -3” which means 80 g protein, 3 g sodium, and 3 g potassium daily. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 22

Diet During Dialysis Healthy people ingest from 2, 000 to 6, 000 mg of potassium per day. Daily intake allowed clients in renal failure is 3, 000 to 4, 000 mg. End stage renal disease clients intake allowed is 1, 500 to 2, 500 mg per day. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 23

Diet After Kidney Transplant Need for extra protein or for the restriction of protein. Carbohydrates and sodium may be restricted. Additional calcium and phosphorus may be necessary if there was substantial bone loss before the transplant. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 24

Stop and Share A client with renal disease is on a potassium restriction of 3, 000 mg. What recommendations would you give the client? Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 25

Stop and Share Regulate intake by making careful choices. Milk is normally restricted to ½ cup a day because it is high in potassium. Suggest use of potassium content charts to select low potassium foods. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 26

Stop and Share Low potassium (< 150 mg/serving) fruits include: • • • Chapter 19 Applesauce Berries Figs Fruit cocktail Grapes • • Lemon, lime Nectors Mandarin oranges Peaches Pears Plums Rhubarb Copyright © 2003 Delmar Learning, a Thomson Learning company 27

Dietary Treatment of Renal Stones Treatment varies based on type of stone. Clients should drink lots of fluid. Eat a well-balanced diet. Once stones have been analyzed, specific diet modifications may be indicated. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 28

Calcium Oxalate Stones A diet low in calcium can reduce the risk of calcium oxalate renal stones. In fact, higher dietary calcium intake may decrease the incidence of renal stones for most people. Reduce level of oxalate, which is found in beets, wheat bran, chocolate, tea, rhubarb, strawberries, spinach. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 29

Uric Acid Stones Purine-rich foods restricted. Purines are the end products of nucleoprotein metabolism. Found in meats, fish, poultry, organ meats, anchovies, sardines, meat extracts, broths. Usually associated with gout, GI diseases that cause diarrhea, and malignant disease. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 30

Cystine Stones Cystine is an amino acid. Cystine stones may form when the cystine concentration in the urine becomes excessive because of a hereditary metabolic disorder. Increase fluids and recommend an alkaline -ash diet. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 31

Struvite Stones Composed of magnesium ammonium phosphate. Sometimes called infection stones because they develop following urinary tract infections caused by certain microorganisms. Low phosphorus diet is often prescribed. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 32

Considerations for the Health Care Professional Client with renal disease has a lifelong challenge. Develop a trusting relationship with the client. Help motivate clients to learn how to manage their nutritional requirements and help the dietitian assist them. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 33

Conclusion Kidneys rid the body of wastes, maintain fluid, electrolyte, and acid-base balance, and secrete hormones. Entire body is affected by kidney disease. Diet therapy extremely complex. Untreated severe kidney disease can result in death unless client receives dialysis or kidney transplant. Chapter 19 Copyright © 2003 Delmar Learning, a Thomson Learning company 34