Your SlideShare is downloading. ×
21 Murphy   Acute Renal Failure
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×

Saving this for later?

Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime - even offline.

Text the download link to your phone

Standard text messaging rates apply

21 Murphy Acute Renal Failure

1,295
views

Published on

Published in: Health & Medicine

1 Comment
0 Likes
Statistics
Notes
  • niiiiiiiiiiiiiiiiiiiiiiiiiiiice
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
  • Be the first to like this

No Downloads
Views
Total Views
1,295
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
32
Comments
1
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Acute Renal Failure Or The Kidney Is Your Friend Katie Murphy MD September 2007
  • 2. Katie’s Approach to Medical Topics
    • For any topic, I ask the following questions:
        • What Is It? (Definitions, Classifications)
        • Why Do I Care? (Prevalence, Morbidity, Mortality)
        • What Do I Need to Do? (Workup)
  • 3. What Is Acute Renal Failure ?
    • There is no universally accepted definition of acute renal failure (ARF).
  • 4. What Is Acute Renal Failure ?
    • There is no universally accepted definition of acute renal failure (ARF).
    • Commonly used definition is > or = to 0.5mg/dl increase in serum creatinine in 2 weeks or less if the baseline creatinine is less than 2.5mg/dl.
    • If baseline creatinine is greater than 2.5mg/dl, ARF is defined as a greater than 20% increase.
  • 5. What Is Acute Renal Failure?
    • Oliguric Renal Failure
  • 6. What Is Acute Renal Failure?
    • Oliguric Renal Failure
    • Less than 500 ml urine output/day in adults
  • 7. What Is Acute Renal Failure?
    • Oliguric Renal Failure
    • Less than 500 ml urine output/day in adults
    • Derived from the fact that a healthy kidney, if maximally concentrating the urine, will have to excrete 500 ml urine per day to get rid of the daily osmotic load from dietary intake and metabolic byproducts .
  • 8. What Is Acute Renal Failure?
    • Oliguric Renal Failure
    • Less than 500 ml urine output/day in adults
    • Derived from the fact that a healthy kidney, if maximally concentrating the urine, will have to excrete 500 ml urine per day to get rid of the daily osmotic load from dietary intake and metabolic byproducts .
    • Anuric Renal Failure
  • 9. What Is Acute Renal Failure?
    • Oliguric Renal Failure
    • Less than 500 ml urine output/day in adults
    • Derived from the fact that a healthy kidney, if maximally concentrating the urine, will have to excrete 500 ml urine per day to get rid of the daily osmotic load from dietary intake and metabolic byproducts .
    • Anuric Renal Failure
    • Less than 100 ml/day urine output
  • 10. What Is Acute Renal Failure?
    • Oliguric Renal Failure
    • Less than 500 ml urine output/day in adults
    • Derived from the fact that a healthy kidney, if maximally
    • concentrating the urine, will have to excrete 500 ml urine
    • per day to get rid of the daily osmotic load from dietary
    • intake and metabolic byproducts .
    • Anuric Renal Failure
    • Less than 100 ml/day urine output
    • Non-Oliguric Renal Failure
  • 11. Chronic Kidney Disease
    • The new nomenclature for renal disease:
      • Stage 1 CKD: kidney damage but normal GFR (>90ml/min)
      • Stage 2 CKD: mild kidney damage (GFR 60-89ml/min)
      • Stage 3 CKD: moderate kidney damage (GFR 30-59ml/min)
      • Stage 4 CKD: severe kidney damage (GFR 15-29ml/min)
      • Stage 5 CKD: kidney failure (GFR < 15ml/min or ESRD on renal replacement therapy)
  • 12. Why Do We Care ?
    • ARF occurs in 5% of hospitalized patients.
    • ARF has been found to be related to a 20% mortality rate (often infectious or cardiorespiratory)
    • When serum creatinine increases by >3.0mg/dl, mortality approaches 40-50% and thus prompt diagnosis and institution of appropriate treatment is crucial.
  • 13. Etiologies of Acute Renal Failure
    • Pre-Renal
    • Post-Renal
    • Intrinsic or Intra-Renal
  • 14. Pre-Renal Acute Renal Failure
    • Accounts for 60-70% of ARF.
    • Etiologies:
      • True Volume Depletion (blood loss, dehydration)
      • Effective Circulating Volume Depletion (CHF, sepsis)
      • Hypotension (sepsis, meds, cardiogenic shock)
      • ACE-Inhibitors
      • NSAIDS
      • Hepatorenal Syndrome
  • 15. Post-Renal Acute Renal Failure
    • Accounts for 5-10% of ARF.
    • Remember anatomy and have a systematic approach.
    • Etiologies include:
      • Ureteral: Tumors, stones, clot and lymphadenopathy
      • Bladder: Tumors, stones, neurogenic, drugs
      • Prostate: Hypertrophy, tumors
      • Urethral: Strictures, tumors
  • 16. Intrinsic Renal ARF
    • Accounts for 25-40% of
    • ARF.
    • Again, remember the
    • component anatomy
    • of the kidney .
  • 17. Intrinsic Renal ARF
    • Accounts for 25-40% of ARF.
    • Again, remember the component anatomy of the kidney .
    • Vessels : Vasculitis, Emboli
    • Glomerulus : Nephrotic syndromes, Nephritic Syndromes
    • Tubules : Acute Tubular Necrosis, Rhabdomyolysis, Contrast Nephropathy
    • Interstitium(peri-tubular and peri-arteriolar tissue) : Acute Interstitial Nephritis, Severe Pyelonephritis .
  • 18. What Do We Need to Do ?
    • First, you need to suspect acute renal failure.
    • Presentation of ARF:
        • Most patients are asymptomatic, but symptoms include
        • Malaise Hypertension
        • Hematuria Encephalopathy
        • Flank Pain Pruritis
        • Dyspnea Bleeding from platelet
        • dysfunction
        • Edema Oliguria/Anuria
  • 19. What Do We Need to Do Part 2
    • Now, we need to look for risk factors, symptoms and signs
    • History:
      • Drugs: Anticholinergics, IV Contrast, Aminoglycosides, Amphotericin.
        • Classic AIN Medications:
          • Penicillins
          • Cephalosporins
          • Sulfa drugs
          • NSAIDS
          • Rifampin
  • 20. History Continued
    • Causes of Volume Depletion
    • Autoimmune Disease
    • Previous History of ARF
  • 21. Physical Exam
    • Volume Status:
      • Tachycardia
      • Mucous membranes
      • Orthostatics
      • Vital signs
  • 22. Physical Exam Continued
    • Dermatologic: Rashes, petechia, purpura
    • Abdomen: CVAT, enlarged bladder.
    • Mental Status: Altered Mental Status
    • CV: Pericardial friction rub
  • 23. What Do We Need to Do ? Part 3
    • We need to act quickly to initiate workup
    • Labs and Studies:
    • Stat:
    • BMP UA with micro
    • Una Ucr
    • Uosm:
        • >400 in pre-renal
        • <350 in post-renal
        • <350 in intrinsic renal
  • 24. UA Interpretation
    • Hyaline Casts : Not indicative of renal disease
      • Concentrated urine, febrile disease, post-strenuous exercise, diuretic therapy
      • Granular Casts : Degenerating cellular casts, non-specific
      • RBC Casts : Glomerulonephritis, vasculitis
      • WBC Casts : Pyelonephritis, Interstitial nephritis
      • Renal Tubular Cell Casts : Nonspecific, degenerating cellular casts
      • Waxy casts : Chronic renal failure
  • 25. Labs and Studies Continued
    • In oliguric ARF, calculate FeNa:
    • <1% (pre-renal, acute GN, contrast, hepatorenal),
    • >1% Intrinsic renal failure (Damaged kidney can not concentrate urine, loses Na)
        • Una/Pna x 100
        • Ucr/PCr
        • FeNa has a 96% sensitivity and a 95% specificity for distinguishing pre-renal from ATN.
        • Not accurate with diuretics.
  • 26. Studies and Labs Continued
    • Renal Ultrasound
      • r/o hydronephrosis
      • Bilateral Small Kidneys: Chronic Renal Disease
      • Unilateral Small Kidney: Renal Artery Stenosis
      • Enlarged Kidneys: HIV, amyloid, PCKD, early DM
  • 27. Treatment
    • Place Foley or flush Foley if already present.
    • As a large percentage of ARF is pre-renal, IVF challenge appropriate in many cases.
    • Evaluate for life-threatening complications:
      • A:
      • E:
      • (I):
      • O:
      • U:
  • 28. Treatment
    • Place Foley or flush Foley if already present.
    • As a large percentage of ARF is pre-renal, IVF challenge appropriate in most cases.
    • Evaluate for life-threatening complications:
      • A: Acidemia
      • E: Electrolyte Abnormalities (Hyperkalemia)
      • (I: Ingestion)
      • O: Overload (CHF)
      • U: Uremic Encephalopathy or pericarditis
      • ALL OF THE ABOVE ARE INDICATIONS FOR EMERGENT HEMODIALYSIS
  • 29. Treatment Continued
    • D/C all meds with kidney damaging potential and adjust dosing of renally cleared meds.
    • Monitor strict Is/Os, follow CBC to evaluate for anemia and bleeding disorders.
    • Control hyperkalemia
    • No longer recommended to give furosemide to convert anuric to oliguric renal failure.
    • Consult renal for intra-renal or rapidly progressive renal failure.
  • 30. An Ounce of Prevention...
    • Check troughs after third dose of aminoglycosides.
    • Use oral N-acetylcysteine or bicarbonate for contrast loads in patients with risk factors for ARF.
    • Avoid diagnostic studies involving contrast unless absolutely necessary.
    • Monitor Is/Os in patients with ESLD, febrile states, prolonged NPO.
  • 31. Where Can I Learn More About Acute Renal Failure?
    • Acute Renal Failure Core Curriculum Handout
    • Thadhani, et. Al., “Acute Renal Failure,”NEJM, May 30, 1996 Review Article
    • Agrawal,N., et. Al., “Acute Renal Failure,” APF 2000;61:2077-2088.
    • Your local public library