The Renal System Overview: Function, Tests & Nursing Implications

1. THE RENAL SYSTEM AT A GLANCE Julie, Ashley, Christen, Candace, Jennifer, Sarah, & Cindy

2. Objectives BUN • When is it used • Nursing implications • Normal values • Abnormal result Creatinine • When it is used • Nursing implications • Normal values • Abnormal result Creatinine Clearance • When it is used • Nursing implications normal values • Abnormal result Tests for BUN/Creatinine Renal Diseases/Illnesses Dialysis Methods

3. Blood Urea Nitrogen • Measures the amount of urea nitrogen in the blood • Urea is formed in the liver as the end product of protein metabolism and digestion • Protein is broken down into amino acids during ingestion, once in the liver, these amino acids are catabolized and free ammonia is formed. • Ammonia molecules are combined to form urea, which is then transported by the blood to the kidneys for excretion.

4. When is BUN Used? • Used to assess kidney function and liver function as well as glomerular filtration rate. • Levels reflect the balance between the production and excretion of urea. • It may also be used to determine if body fluids are urine or not.

5. Nursing Implications • Explain procedure to the patient • Provide teaching regarding what the test will be measuring. • Inform the patient that no fasting is required with this test. • Monitor puncture site for bleeding

6. Normal Values • Normal values for an adult under the age of 90 years old are 2.9-7.5 mmol/L • For patients over the age of 90, levels are 3.6-11.1 mmol/L

7. BUN • Cardiac Patients • Reduced Renal Perfusion • Intravascular Fluid Volume Deficit • Increase as GFR decreases • ARF • CRF • Dehydration • Altered Protein intake • Protein Catabolism

8. Creatinine • End product of creatine metabolism. • Creatineis an energy-requiring metabolite of the skeletal muscle. • Creatineis converted to creatinine during metabolism where it is filtered through the kidney’s and excreted. • Only a small amount of creatine is converted to creatinine, this level remains stable except when there is damage to skeletal muscle. • The measuring of creatinine is an indicator of renal function

9. Indications • Before administration of nephrotoxix medications, to assess renal function • Check glomerular function • Monitor effectiveness of renal treatment • Check accuracy of 24 hour urine collection • Assess level of nephrondamage

10. Normal Values

11. Nursing Implications • Inform patient the test if used to assess renal function • Obtain a detailed history, including medications • Discuss procedure with patient • Instruct patient as to proper procedure for urine collection. • Discuss with patient the process of a 24 hour urine collection.

12. Factors effecting levels Creatinine • Extremes of age and body size • Severe malnutrition or obesity • Disease of skeletal muscle • Paraplegia or quadriplegia • Vegetarian diet • Rapidly changing kidney function • Pregnancy

13. Creatinine • Increased In: • Nephritis • Chronic Renal Disease • Decreased In: • Muscular Atrophy • Anemia • Advanced Degeneration of the Kidneys

14. Creatinine Clearance • Diagnostic test of renal function • Compares the amount of creatinine in a blood sample and urine sample to determine rate the kidneys are clearing creatinine from the blood • Measure of glomerular filtration rate

15. Indications • Determine extent of nephron damage in known renal disease • Before administering nephrotoxic drugs • Accuracy of 24-hr urine collection • Assess glomerular function • Effectiveness renal disease treatment

16. Normal Values • Adult male 85-125mL/min/1.73 m • Adult female 75-115mL/min/1.73 m • Each decade after 40 y decrease of 6-7 mL/min/m (conventional units x 0.0167)

17. abnormal result • Degree of impairment: • Borderline: 62.5-80 mL/min/m • Slight: 52-62.5 mL/min/m • Mild: 42-52 mL/min/m • Moderate: 28-42 mL/min/m • Marked: Less than 28 mL/min/m 2

18. Nursing Implications • Inform patient of test • Obtain pt. genitourinary history & results of related tests/procedures • Obtain list of medications pt. taking • Review procedure • Inform pt. urine timeframe of urine collection & to void all urine in collection device • Sensitivity to social & cultural issues

19. Creatinine Clearance • Decreased In: • Kidney Diseases • Acute Renal Failure • Chronic Renal Failure • Increased In: • Diabetes • Renal Artery Obstruction • Renal Vein Thrombosis • Glomularulonephritis • Nephritis

20. Tests For... Creatinine BUN Blood/serum: Serum (about 1mL) collected in a red or tiger- top tube. Or Plasma collected in green- top (heparin) tube is also acceptable • Blood/serum: • Serum (about 1mL) collected in a red or tiger- top tube. Or • Plasma collected in green- top (heparin) tube is also acceptable • Urine: • Urine (5mL) collected from an unpreserved random or timed specimen – needs to be collected in a clean plastic collection container

21. How to Test... Blood Urine

22. Random Specimen Clean Catch Timed Obtain a 3L urine specimen container, toilet-mounted collection device and a plastic bag for transporting the specimen container • Female client procedure • Male client procedure

23. Dialysis • When your kidney’s cannot adequately remove waste from your body dialysis may be implemented • Pts can survive on dialysis for years • The only way to stop dialysis (and still survive) is to have a kidney transplant

24. Why Have Dialysis? Because it treats: • Renal Failure • Edema • Hepatic coma • Hyperkalemia • Hypercalcemia • Hypertension • Uremia • Fluid overload • Pulmonary edema • Acidosis • Pericarditis • Severe confusion

25. There are 2 Types of Dialysis Hemodialysis Periotoneal Dialysis

26. Hemodialysis • Hemodialysisworks to • remove toxins (N) & excess water from the blood stream • maintain and restore the electrolyte balance & acid-base buffer system (done in the dialyzer) • have ‘clean’ or filtered blood re enter the body as it would when leaving the kidney

27. Dialyzer The blood filtering device • Filtration through: • Diffusion – how the toxins are removed • Osmosis – takes away extra water • Ultrafiltration – takes away extra water

28. Complications • Artherioscleroticcardiovascular disease • Hypertriglyceridema • Amemia • Fatigue • Gastric ulcer • Fluid overload • Exsangulation • Hypotension • Muscle cramping • Air emboli • Dysrythmia • Chest pain • Cerebral fluid shifts

29. Peritoneal Dialysis • Peritoneal dialysis is implemented to... • Remove the toxic fluids • Remove metabolic wastes • Re-establish normal fluid and electrolyte balance. Who needs treatment? Who should not receive this treatment? How to patients receive this treatment? How does this effect a patient receiving this treatment?

31. Complications • Peritonitis • Leakage • Bleeding • Hypertriglyceridemia • Abdominal hernias • Clot Formation • Constipation

32. References • Day, R.A., Paul, P., Williams, B., Smeltzer, S.C. & Bare, B. (2006). Textbook of medical-surgical nursing. Philadelphia, PA: Lippincott Williams and Wilkins. • McCance, K.L. & Huether, S.E (2006). Pathophysiology: The biological basis for disease in adults and children. St. Louis, MO: Elsevier Mosby. • Myers, T. (Ed.). (2006). Mosby’s dictionary of medicine, nursing and health professions (7th ed.). St. Louis, MO: Mosby Elsevier. • Pagana, K.D. & Pagana, T.J. (2010). Mosby’s manual of diagnostic and laboratory tests (4th ed.) St. Louis, MO: Mosby’s Elsevier Inc. • Van Leeuwen, A.M, Kranpitz, T.R and Smith, L. (2006). Davis’s comprehensive handbook of laboratory and diagnostic tests withnursing implications (2nd ed.). Philadelphia, PA: F.A Davis Company.