Acute Renal Failure

Causes
1. Preprenal
  1. Hypoperfnusion due to: 1-CHF 2-Renal artery stenosis 3-thrombosis 4-dehydration
    1. BUN/CR ratio >15 FEna <1% Urine osm >500nn
  2. Hypovolemic shock
2. Renal
  1. 1-acute tubular necrosis
    1. Ischemic: Hypotension-shock-Renal vascular diseases.
    2. Nephrotoxic: Toxins (drugs-radigraphic contrast- mercury-Heamoglobinuria – myoglobinuria)
  2. 2-tubule-interstitial nephritis
    1. Infectious type. Mostly bacterial :"Pyelonephritis”
    2. Non-infectious types: drugs (hypersensitivity), toxins, physical(obstruction), Multiple myeloma, immunologic, and vascular causes
3. Postrenal
  1. Obstruction below kidney’s level: 1-tumor 2-stones 3-prostate hypertrophy
    1. Early stage *acute*: BUN/CR ratio >15 FEna <1% Urine osm >500
    2. Chronic long term: BUN/CR ratio <15 FEna >2% Urine osm <500
Definition
1. a rapid decline in kidney function that can lead to long-term kidney damage and death. It is often preventable or reversible
Epidemiology
1. Affects 5-7% OF ALL HOSPITALISED PATIENTS 20-70% MORTALITY RATE
Signs & Symptoms
1. azotemia (High BUN/creatinine) Oliguria or polyuria Fluid retention (edema) Shortness of breath Fatigue and Confusion Seizures or coma Chest pain or pressure Foamy or bubbly urine
2. Can be Asymptomatic!
Investigations
Management
1. Hydration hyperkalemia Pulmonary edema Fluid retention Acidosis
2. Diuretics
  2. Tubular Reabsorption function
Complications
1. Fluid buildup Chest pain Muscle weakness Chronic Renal Failure

Resource summary

	Created by Group I about 6 years ago