ACUTE RENAL FAILURE

1. ACUTE RENAL FAILURE INTERN EMERGENCY LECTURE SERIES 2005

2. ABRUPT DECREASE IN RENAL FUNCTION RESULTING IN THE ACCUMULATION OF NITROGENOUS COMPOUNDS SUCH AS UREA AND CREATININE DEFINITION

3. A

4. Acute vs Chronic Renal Failure • History • Known Chronic • Recent Toxic Exposure • Recent Hypoxic Insult • Recent Trauma • Known Diseases Associated with ARF • Prev. Abnormal Lab Results Suggesting Chronic

5. Acute vs Chronic Renal Failure • Rapidly Rising Creatinine = Acute • Kidney Size • Small = Chronic • Renal Ultrasound • Increased Echogenicity = Chronic • Urine Flow Rate • Oliguric or Anuric usually = Acute

6. ACUTE RENAL FAILURE CLASSIFICATION BY URINE VOLUME OLIGURIC: <400 CC/ 24 Hrs NON-OLIGURIC: >500 CC/24 Hrs ANURIC <50 CC/24 Hrs

7. ETIOLOGY OF ACUTE RENAL FAILURE • PRE-RENAL 55-60% • POST RENAL <5% • RENAL 35-40%

8. PRE-RENAL ACUTE RENAL FAILURE • MOST COMMON CAUSE OF ARF • RESULTS FROM DECREASED RENAL PERFUSION • TREATMENT OF THE CAUSE RESTORES RENAL FUNCTION TUBULAR FUNCTION INTACT * • PROLONGED PRE-RENAL FAILURE MAY LEAD TO ATN

9. CAUSES OF PRE-RENAL AZOTEMIA • Intravascular volume depletion • Decreased cardiac output • Systemic vasodilation • Antihypertensives • Sepsis • Renal vasoconstriction • Drugs impairing autoregulation • Ace inhibitors NSAID

10. MECHANISMIS OF PRE RENAL ARF

12. POST-RENAL ACUTE RENAL FAILURE • ACCOUNTS FOR 2-15% OF ALL ARF • OBSTRUCTION TO URINE FLOW • INCREASED TUBULAR PRESSURE • VASOCONSTRICTION • DECREASED RENAL BLOOD FLOW • MUST BE BILATERAL TO RESULT IN ARF • UNLESS : SINGLE KIDNEY OR PRIOR CHRONIC RENAL FAILURE

14. POST RENAL ACUTE RENAL FAILURE • SUSPECT OBSTRUCTION IN ANURIA • ETIOLOGY MAY BE AGE DEPENDENT • YOUNG = CONGENITAL ABNORMALITY • OLDER MALE = PROSTATIC ENLARGEMENT • ARF MOST OFTEN ASSOCIATED WITH LESIONS IN: • BLADDER, PROSTATE OR URETHRA

16. RENAL-ACUTE RENAL FAILURE • VASCULAR DISEASE • VASCULITIS (SLE, POLYARTERITIS ETC.) • SCLERODERMA • THROMBOEMBOLIC DISEASE • MALIGNANT HYPERTENSION

17. RENAL--ACUTE RENAL FAILURE • GLOMERULAR DISEASE • ACUTE GLOMERULONEPHRITIS • POST INFECTIOUS GN • CRESCENTIC GN • ANCA POSITIVE DISEASES • GOODPASTURE’S DIS. • ANTI- GLOMERULAR BASEMENT ANTIBODY

18. RBC CAST

19. PENICILLINS SULFONAMIDES CEPHALOSPORIN RIFAMPIN ( 2ND TIME) QUINOLONES NSAID (FENOPROFEN) ALLOPURINOL PHENYTOIN THIAZIDES FUROSEMIDE CIMETIDINE ACUTE INTERSTITIAL NEPHRITISDRUG INDUCED

20. Acute Interstitial Nephritis • Fever • Rash • Eosinophilia • Pyuria • Eosinophiluria • WBC Casts

21. WBC Cast

22. RENAL --ACUTE RENAL FAILURE • ACUTE TUBULAR NECROSIS • ISCHEMIC INJURY • TOXIC INJURY • ENDOGENOUS TOXINS • HEMOGLOBINURIA • MYOBLOBINURIA (RHABDOMYOLYSIS) • ENDOTOXEMIA

23. RENAL-- ACUTE RENAL FAILURE • ACUTE TUBULAR NECROSIS • EXOGENOUS TOXINS • AMINOGLYCOSIDES • RADIOGRAPHIC CONTRAST • HEAVY METAL COMPOUNDS • ETHYLENE GLYCOL • METHANOL • CARBON TETRACHLORIDE • CIS PLATIN

24. HIGH RISK SETTINGS FOR ATN CLINICAL SETTING FREQUENCY • GEN.MED. --SURG. 3-5% • INTENSIVE CARE 5-25% • OPEN HEART SURG 5-20% • AMINOGLYCOSIDE 10-30% • BURNS 20-60% • RHABDOMYOLYSIS 20-30% • CIS-PLATIN 15-25%

25. ATN SEDIMENT

26. DIAGNOSTIC APPROACH TO ARF • HISTORY • PHYSICAL EXAMINATION • ASSMENT OF URINE VOLUME • URINE ANALYSIS • BLOOD CHEMISTRY • BLOOD AND URINE INDICES • RADIOLOGIC STUDIES

28. Treatment of ARF

29. Hyperkalemia • Never occurs in the absence of renal excretory problem • Pseudohyperkalemia • Leukocytosis • Thrombocytosis • Prolonged Application of Tourniquet

30. Hyperkalemia • Significance of urine output • Role of increased catabolism or tissue breakdown • Factors affecting shift of Potassium out of cells • Etiololgy of the renal failure

31. Treatment of Hyperkalemia • Urgency • Role of the EKG in making the decision • Clinical setting in which it occurs • Acute renal failure • Chronic renal failure

33. Table 5-3. Treatment of hyperkalemia Medication Mechanism of action Dosage Peak effect Calcium Antagonism of 10-30 ml of 10% solution IV -5 min gluconate membrane over 2 min Insulin and Increased K+entry Insulin, 10 U IV bolus 30-60 min Glucose into the cells followed by 0.5 mU/kg of body weight per minute in 50 ml of 20% glucose Sodium Increased K+entry 44-50 mEq IV over 5 min; 30-60 min bicarbonate into the cells can be repeated within 30 min Albuterol Increased K+entry into the cells 20 mg in the nebulized form 30-60 min Kayexalate Removal of the 20 g of resin with 100 ml of 2-4 hr excess K+ 20% sorbitol; can be repeated every 4-6 hr Hemodialysis Removal of the Dialysis bath K+ concentration 30-60 min excess K+ variable

34. INDICATIONS FOR DIALYSIS IN ACUTE RENAL FAILURE UREMIC SYMPTOMS ~ nausea ~neurologic SEVERE FLUID OVERLOAD REFRACTORY ELECTROLYTE DISORDERS ~hyperkalemia SEVERE REFRACTORY ACIDOSIS

35. INDICATIONS FOR DIALYSIS IN ACUTE RENAL FAILURE • PERICARDITIS • NEUROPATHY • MENTAL STATUS CHANGE • SEIZURES • BLEEDING • TOXINS----ETHYLENE GLYCOL, METHANOL • PROPHYLACTIC ~recent studies fail to document benefit

36. MORTALITY ASSOCIATED WITH SETTING OF ATN • OVERALL MORTALITY 40-60% • POST TRAUMATIC 70-90% • MEDICAL CAUSE 15-40% • SURGICAL CAUSE 40-80% • NON-OLIGURIC 26% * • OLIGURIC 50% *

37. CAUSES OF DEATH IN ATN