RCS 6080 Medical and Psychosocial Aspects of Rehabilitation Counseling Renal Failure Function of Kidneys Remove toxic waste products Remove excess water and salts Play a part in controlling blood pressure Produce erythropoetin (epo) which stimulates red cell production Helps to keep calcium and phosphate in balance for healthy bones Maintains proper pH for the blood Definitions Azotemia: Elevated blood urea nitrogen (BUN>28mg/dL) & Creatinine (Cr>1.5mg/dL) Uremia: azotemia with symptoms or signs of renal failure End Stage Renal Disease (ESRD): uremia requiring transplantation or dialysis Chronic Renal Failure (CRF): irreversible kidney dysfunction with azotemia >3 mos. Creatinine Clearance (CCr): rate of filtration of creatinine by the kidney (marker for GFR) Glomerular Filtration Rate (GFR): the total rate of filtration of blood by the kidney. Nephrons Nephrons are the units in the kidney that transfer waste products from the blood to urine. A human kidney has approximately one million nephrons. Glomeruli are the filtration units of the nephron. The Glomerulus (first structure of the nephron) is a tuft of capillaries. Blood enters the glomerulus by the afferent arteriole and exits by the efferent arteriole Bowman’s capsule is a tough layer of epithelial cells that surrounds the glomerulus ;there is a small holding area for the initial filtrate in between the capillary walls of the glomerulus and the inner layer of Bowman’s capsule; this area is called Bowman’s space. Fluid and solutes filtered by the glomerulus collect in this space. The space connects to the proximal convoluted tubule, which is the first section of the nephron’s tube system a network of tubules extends from Bowman’s capsule: proximal convoluted tubule (PCT) Loop of Henle—has a descending and ascending limb distal convoluted tubule Collecting duct Renal Failure Acute Renal Failure Prerenal azotemia An abnormally high level of nitrogen-type wastes in the bloodstream. It is caused by conditions that reduce blood flow to the kidneys. Postrenal azotemia An obstruction of some kind (i.e., bladder cancer, uric acid crystals, urethral stricture etc) Intrinsic Renal Disease Usually glomerular disease Usually leads to End Stage Renal Disease Chronic Renal Failure Diabetic Nephropathy 50K cases of DN ESRD annually Diabetes most common contributor to ESRD >30% of ESRD cases attributed to Diabetes Hypertension CFR with Hypertension causes 23% of ESRD annually Glomerulonephretis: 10% Polycystic Kidney Disease: 5% Rapidly progressive glomerulonephrities (vasculitis): 2% Renal Vascular Disease (i.e., renal artery stenosis) Medications Analgesic Nephropathy (progression after many years) Pregnancy: high incidence of increased creatitine and HTN during pregnancy associated with CRF Chronic Renal Failure CRF is defined as a permanent reduction in glomerular filtration rate (GFR) sufficient to produce detectable alterations in well-being and organ function. This usually occurs at GFR below 25 ml/min. About 100 to 150 per million persons in the U.S. develop CRF annually Average annual cost is $25,000 – 35,000 per patient per year Stages of Chronic Renal Failure 1. 2. 3. 4. Silent – GFR up to 50 ml/min. Renal insufficiency – GFR 25 to 50 ml/min. Renal failure – GFR 5 to 25 ml/min End-stage renal failure – GFR less than 5 ml/min. Diabetic Nephropathy What can be done to reduce the risk of problems? Blood glucose control Blood pressure control Using ACE inhibitors and AT II antagonists Diet Controlling blood lipids and cholesterol Smoking Treatment for Diabetic Nephropathy Stage Assessment Treatment No Proteinuria Monitor BP & Glucose Screen for micoalbumininuria Hypertension drugs if needed (BP should be 130/85 or lower). Dietary advice for sugar and fat, stop smoking Microalbuminuria Close monitoring of BP, Glucose and blood lipids, monitor urinary proteins & CCr Add more Hypertension drugs if needed needed. Monitor cholesterol and add ACE inhibitor if needed Proteinuria Close monitoring of BP, glucose and blood lipids, monitor urinary protein and 24 CCr BP should be lower than 125/75, low protein diet Declining kidney function Prepare for dialysis &/or transplant Metabolic changes Na+ excretion initially increased Edema occurs when GFR continues to diminish. NH4+ excretion declines adding to metabolic acidosis. Bone CaCO3 begins to act as a buffer for the acidosis and leading to chronic bone loss and bone lesions develop (renal osteodystrophy). Accumulations of normally secreted uremic toxins Uremic Syndrome Uremia occurs in stage 3 & 4 of CRF. It means literally “urine in the blood” Symptomatic azotemia Fever, Malaise Anorexia, Nausea Mild neural dysfunction Uremic pruritus (itching) Associated problems with CFR Immunosuppression Increased risk of infection People with CFR should be vaccinated regularly Anemia Due to reduced erythropoietin production by kidney. Usually doesn’t occur until 6-12 mos prior to dialysis Hyperuricemia (Gout) Increased uric acid in system Pain in joints, may contribute to renal dysfunction Hyperphosphatemia Increased parathyroid hormone levels Increased phosphate load from bone metabolism Hypertension Poor coagulation Proteinuria Chronic Renal Failure Chronic Renal Failure and Its Progression Functional Adaptation to Nephron Loss Increased amount of sodium that escapes reabsorption Excessive amount of potassium in blood Increased ammonia concentration Calcium and phosphorus metabolism are markedly altered Treatment of Chronic Renal Failure Hypertension Metabolic Acidosis Anemia Renal Osteodystrophy Uremic Neuropathy Sexual Dysfunction Conservative Treatment Dialysis Hemodialysis Transplant Peritoneal Home Related Donor Center Cadaver Donor Treatment of End Stage Renal Failure Hemodialysis Uses a mechanized filter to remove impurities from the blood system Essentially replaces kidney with a machine Dialysis usually occurs a couple times per week. Hemodialysis Vascular preparation Surgical procedures usually completed weeks before beginning hemodialysis Treatment of End Stage Renal Failure Peritoneal Dialysis Uses the abdominal cavity as a filter Treatment of End Stage Renal Failure Transplantation Treatment of End Stage Renal Disease Survival of People with ESRD Data show a mean expected remaining life span of just under 8 years for people 40-44 beginning dialysis and just over 4 years for people 60-64 Adequacy of Dialysis Nutrition Chronic Renal Failure Physical Rehabilitation – benefits of exercise Vocational Rehabilitation The goal should be to help the person with chronic renal failure to resume all the duties, responsibilities and benefits he or she enjoyed prior to the illness Gainful employment is extremely important for an adult in the earning period of his or her life, to regain selfesteem and to interact with society confidently Fear of losing financial benefits may deter some people Some research has shown that multidisciplinary predialysis intervention leads to maintenance of job Additional Resources and Information from the Web Florida End Stage Renal Disease Network (http://www.fmqai.com/ESRD/esrd.htm) University Renal Research and Education Association (www.urrea.org) National Institute of Diabetes & Digestive & Kidney Diseases (www.niddk.nih.gov) National Kidney & Urologic Diseases Information Clearinghouse (NKUDIC) (http://kidney.niddk.nih.gov/) Life Options Rehabilitation Program (www.lifeoptions.org) United Network for Organ Sharing (UNOS) (http://www.unos.org) American Society of Nephrology (www.asn-online.org) National Kidney Foundation (www.kidney.org) JAN’s webpage (www.jan.wvu.edu/soar/other/renal.html)