RIFLE Criteria Simplified acute kidney injury
What is the Pediatric RIFLE Criteria?
The Pediatric RIFLE (pRIFLE) criteria classify the severity of acute kidney injury (AKI) based on changes in serum creatinine, glomerular filtration rate (GFR), and urine output.
Criteria Breakdown:
- Risk (R): GFR decreased by 25% or urine output < 0.5 mL/kg/hr for 8 hours.
- Injury (I): GFR decreased by 50% or urine output < 0.5 mL/kg/hr for 16 hours.
- Failure (F): GFR decreased by 75% or anuria for 12 hours.
- Loss (L): Persistent failure for over 4 weeks.
- End-Stage (E): Persistent failure for over 3 months.
Clinical Implications:
Early recognition using pRIFLE helps guide interventions like fluid resuscitation, diuretics, or renal replacement therapy.
Urinary Indices in Acute Renal Failure: 5 Key Insights
Top Urinary Indices to Assess Acute Renal Failure:
- Fractional Excretion of Sodium (FENa):
- Prerenal: <1%
- Intrinsic: >2%
- Urine Sodium:
- Prerenal: <20 mmol/L
- Intrinsic: >40 mmol/L
- Urine Osmolality:
- Prerenal: >500 mOsm/kg
- Intrinsic: <350 mOsm/kg
- Urine/Plasma Creatinine Ratio:
- Prerenal: >40
- Intrinsic: <20
- Specific Gravity:
- Prerenal: High
- Intrinsic: Low
Clinical Relevance:
These indices help distinguish prerenal AKI from intrinsic renal damage, tailoring patient management.
Acute Renal Failure Demystified: Pathophysiology, Causes, Symptoms, and Treatment
What is Acute Renal Failure?
Acute renal failure (ARF) is a rapid decline in kidney function, impairing waste elimination and fluid balance.
Pathophysiology:
- Reduced renal perfusion → ischemia → tubular damage → decreased GFR.
- Causes: Prerenal (hypovolemia), intrinsic (glomerulonephritis), postrenal (obstruction).
Key Causes:
- Prerenal: Sepsis, dehydration, blood loss.
- Intrinsic: Acute tubular necrosis, nephrotoxins.
- Postrenal: Kidney stones, tumors, urethral stricture.
Clinical Features:
- Early: Oliguria, rising serum creatinine.
- Late: Uremia, acidosis, hyperkalemia.
Management:
- Initial: Fluid resuscitation, electrolyte balance, avoid nephrotoxic drugs.
- Definitive: Dialysis in severe cases.
