Acute Renal Failure

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Acute Renal Failure

• 24/3/04

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Acute Renal Failure

• AIMS
• Relate session to student group (Anaesthetics,
  Burns, Cardiothoracic, Theatre)
• Etiologies relating to above clinical practice
  setting
• Normal Renal Function-overview
• Measurement of Renal Function
• Pathophysiology of Hypovolaemia, Reperfusion,
  Nephrotoxicity

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Acute Renal Failure

• AIMS
• Continued
• Uraemic Syndrome
• U Es-interpretation of findings
• Screening differential diagnosis
• Controversial Therapies
• Therapies Conservative/Palliative Measures,
  Dialysis, Prevention.

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Acute Renal Failure

• NORMAL FUNCTION
• Kidney- a complex metabolic organ. Active
  metabolism, bioconversion.
• Location of Kidneys RE Cardiac
• Creatine/Creatinine Urea, other indeces of
  function.
• GFR pre-requisits
• GFR Cr Cl Acute compared to Chronic
• Urea Creat ratios

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Acute Renal Failure

• Etiology of Hypovolaemia
• Fluid Compartments Starlings Forces
• Hypotension, Hypovolaemia
• Azotemia
• ATN

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Acute Renal Failure

• Pathophysiology of
• Hypovolaemia
• Pre-Renal Azotemia
• ATN

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Acute Renal Failure

• Pathophysiology of
• Hypovolaemia- haemodynamic mechanisms
• Pre-Renal Azotemia-Intra-glomerulat dynamics.
  Tubule intact
• ATN- Autoregulation fails. Cellular changes

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Acute Renal Failure

• Pathophysiology of ATN
• Ischaemia
• Necrosis
• Theories of Oliguria
• Glomerular versus Tubular regeneration, recovery

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Acute Renal Failure

• ACUTE INFLAMMATION
• Consequences of hypoxia and other stressors
• Triggers, agents mediators
• ATPase-Na, K, Ca. Membrane pumps
• (see Acute Inflammation handout for mechanism of
  injury)

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Acute Renal Failure

• REPERFUSION
• Based on Acute Inflammmation mechanism
• Therapeutic interventions inducing Reperfusion
• Exacerbation of mechanism- production of Free
  Radicals
• The Stressed Kidney

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Acute Renal Failure

• ACUTE INTERSTITIAL NEPHRITIS
• Pathophysiology of Nephrotoxicity
• Haemodynamic (RBF GFR)
• Direct Tubular Toxicity-Rhab myoglobin
• Osmotic Nephrosis
• Precipitation/ Crystalisation
• ACEIs NSAIDS, AMINOGLYCOSIDES, CYSTPLATIN,
  FRUSEMIDE

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Acute Renal Failure

• Nephrotoxicity Risk Factors
• Drug combinations
• Age
• Comorbidity
• Renal insufficiency
• Reduced CAD
• Na retaining states

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Acute Renal Failure

• Uraemic Syndrome- ss
• Abnormal KCaNa PO4 Creat Urea
• Hypo/ Hyper KCaNa PO4 interpretation
• Abnormal UrCr ratios in ATN Azotemia
• Urine Screening of ATN Azotemia
• Differential Diagnosis purpose, problems

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Acute Renal Failure

• Concept of Reno-protection
• Therapies
• Remove Primary Factor
• Resuscitate
• Conservative/Palliative measures (Fluids, UEs,
  Acidosis)
• Dopamine Frusemide- Evidence controversies
• Infection
• Nutrition
• Prevention of complications

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Acute Renal Failure

• DIALYSIS THERAPIES
• Indications
• Clinical settings
• Principles
• Convective Therapies CVVHD
• Coagulopathy and heparin free dialysis
• Peritoneal Dialysis