Identifying & Managing Acute Renal Injury

1. Identifying & Managing Acute Renal Injury Leanna R. Miller, RN, MN, CCRN-CSC, PCCN-CMC, CEN, CNRN, CMSRN, NP Education Specialist LRM Consulting Nashville, TN

2. Acute Renal Injury Objectives • Discuss the significance of the RIFLE classification for renal dysfunction. • Differentiate between pre – renal, intra – renal and post – renal failure with regard to etiologies, diagnosis and treatment. • Utilizing a case study, identify management strategies of a patient with renal dysfunction

3. Acute Renal Injury Definition • rapidly progressive • potentially reversible cessation of renal function • UO < 0.5 mL/kg/hr

4. Acute Renal Injury

5. Acute Renal Injury • Renal Failure Index (RFI) • RFI = UNa x SCr/UCr • Intrepretation • RFI < 1 (prerenal failure) • RFI > 1 (intrarenal failure)

6. Acute Renal Injury • Fraction Excreted Sodium (FENa) • FENa = Una X PCr / Pna X Ucr  x 100 • Intrepretation • FENa < 1 (prerenal failure) • FENa > 1 (intrarenal failure)

7. Acute Renal Injury • Renal Failure Index (RFI) • RFI = UNa x SCr/UCr • Example • RFI < 1 • UNa < 20 mEq/L • FENa < 1% • UCr/SCr > 30

8. Acute Renal Injury • Renal Failure Index (RFI) • RFI = UNa x SCr/UCr • Example • RFI > 1 • UNa>40 mEq/L • FENa > 2-3% • UCr/SCr<20

9. Acute Renal Injury • Renal Biomarkers • Urine interleukin – 18 (IL – 18) • Urine or blood NGAL • neutrophil gelatinase – associated lipocalin Increase 24 to 48 hours earlier than creatinine

10. Acute Renal Injury Prerenal Etiology (PRE) • most common type •  volume •  cardiac function • use of vasopressors

11. Acute Renal Injury Prerenal Etiology (PRE) • Diagnostics • BUN/Creatinine ratio • RFI/FENa • urinalysis

12. Acute Renal Injury Postrenal (POST) • obstructive process • structural • functional • lower tract or bilaterally in upper tracts

13. Acute Renal Injury Intrinsic • Diagnostics • BUN/Creatinine ratio • RFI/FENa • urinalysis

14. Acute Renal Injury Intrinsic - kidney • acute tubular necrosis (hypoxic or nephrotoxic) • glomerular disorders (AGN), rhabdomyolysis, postinfectious

15. Acute Renal Injury Intrinsic - kidney • Vascular lesions – blood flow compromise (HUS) • Interstitial nephritis (AIN) reactions to drugs or infections

16. Acute Renal Injury Intrarenal Etiology • Diagnostics • BUN/Creatinine ratio • RFI/FENa • urinalysis

17. Acute Renal Injury Treatment • underlying cause • prevention on injury • high risk patient • hydration • limit exposure

18. Acute Renal Injury Management Principles • maintain fluid balance • manage hyperkalemia • glucose & insulin • calcium gluconate • sodium bicarbonate

19. Acute Renal Injury Clinical Manifestations • hyperkalemia • hypocalcemia • hypermagnesemia • hyperphosphatemia • uremia • acid – base imbalance

20. Acute Renal Injury Management Principles • control hypertension in presence of encephalopathy • bicarbonate for severe acidosis (pH < 7.2) • manage anemia

21. Renal Replacement Therapies

22. Acute Renal Injury Treatment • Replacement Therapies • acidosis • HCO3 < 10 mEq/L • K+ > 6.5 mEq/L • need high protein diet • deteriorating

23. Acute Renal Injury Treatment: • Types • hemodialysis • peritoneal dialysis • continuous renal replacement therapy

24. Acute Renal Injury Treatment • fluid balance • anticoagulation • prevent clotting • prevent blood loss • ultrafiltration

25. Acute Renal Injury Rhabdomyolysis • Causes • trauma • burns • compression syndrome • infection

26. Acute Renal Injury Rhabdomyolysis • Causes • vascular occlusion • prolonged shock • electrolyte disorders • drugs (cocaine, alcohol)

27. Acute Renal Injury Rhabdomyolysis • Clinical Manifestations • myalgias • muscle swelling & weakness • DIC • color of urine

28. Acute Renal Injury Rhabdomyolysis • Lab Values • elevated muscle enzymes • hyperkalemia • hyperphosphatemia • hypocalcemia

29. Acute Renal Injury Rhabdomyolysis • Treatment • volume replacement • treat electrolyte abnormalities • protect renal perfusion • alkalinization of urine • fasciotomy

30. Acute Renal Injury Case Study 1 • 45 – year old female with history of peptic ulcer • 10 – day history of intractable vomiting and abdominal pain • drinking small amounts of water @ frequent intervals • weaker, now complaining of dizziness

31. Acute Renal Injury Case Study 1

32. Acute Renal Injury Case Study 1 • Physical Exam: • tenting of the skin • sunken eyes • dry mucous membranes • flat jugular veins • epigastric tenderness

33. Acute Renal Injury Case Study 1

34. Acute Renal Injury Case Study 1

35. Acute Renal Injury Case Study 2 • 20 – year old male with friends “doing drugs – cocaine” • Police break up party – male runs from police but collaspes – states legs became so weak that he fell • Admitted to ED – lower extremity weakness and severe pain in legs

36. Acute Renal Injury Case Study 2

37. Acute Renal Injury Case Study 2

38. Acute Renal Injury Case Study 2