Renal Failure Overview

Renal Failure

Acute Renal Failure (ARF)

• Definition: Sudden decrease in kidney function; can be reversible.
• Causes:
  • Pre-renal: Decreased blood flow (e.g., dehydration, heart failure).
  • Intra-renal: Damage to kidney tissue (e.g., acute tubular necrosis, glomerulonephritis).
  • Post-renal: Obstruction of urine outflow (e.g., kidney stones, tumors).
• Symptoms:
  • Oliguria or anuria
  • Edema
  • Electrolyte imbalances
  • Nausea and vomiting
• Diagnosis:
  • Serum creatinine and blood urea nitrogen (BUN) levels
  • Urinalysis
  • Imaging (ultrasound, CT scans)
• Management:
  • Treat underlying cause
  • Fluid management
  • Medications (e.g., diuretics)

Chronic Renal Failure (CRF)

• Definition: Gradual loss of kidney function over time; often irreversible.
• Causes:
  • Diabetes mellitus
  • Hypertension
  • Chronic glomerulonephritis
  • Polycystic kidney disease
• Symptoms:
  • Fatigue and weakness
  • Anemia
  • Hypertension
  • Changes in urine output
  • Electrolyte imbalances
• Stages:
  • Stage 1: Mild damage, normal GFR (≥ 90 mL/min)
  • Stage 2: Mild decrease in GFR (60-89 mL/min)
  • Stage 3: Moderate decrease in GFR (30-59 mL/min)
  • Stage 4: Severe decrease in GFR (15-29 mL/min)
  • Stage 5: Kidney failure (GFR < 15 mL/min)
• Management:
  • Control blood sugar and hypertension
  • Dietary modifications
  • Renal replacement therapy (dialysis/transplantation)

Dialysis

• Definition: Treatment that removes waste products and excess fluid when kidneys can't perform these functions.
• Types:
  • Hemodialysis: Blood is filtered through a machine; typically done 3 times a week.
  • Peritoneal Dialysis: Uses the lining of the abdomen to filter blood; can be done at home.
• Indications:
  • Severe electrolyte imbalances
  • Fluid overload
  • Acidosis
  • Uremic symptoms (nausea, vomiting, fatigue)
• Complications:
  • Infection (e.g., access site)
  • Hypotension
  • Anemia
  • Bone disease

Complications of Renal Failure

• Cardiovascular Issues:
  • Hypertension
  • Heart failure
  • Increased risk of cardiovascular disease
• Electrolyte Imbalances:
  • Hyperkalemia (high potassium)
  • Hyperphosphatemia (high phosphate)
  • Hypocalcemia (low calcium)
• Metabolic Disorders:
  • Metabolic acidosis
  • Uremia (buildup of waste in blood)
• Bone and Mineral Disorders:
  • Osteodystrophy (bone pain, fractures)
  • Calciphylaxis (calcification of small blood vessels)
• Anemia:
  • Decreased erythropoietin production
• Infections:
  • Increased susceptibility due to immune dysfunction and dialysis access sites

Acute Renal Failure (ARF)

• Sudden decline in kidney function; potential for reversibility.
• Pre-renal causes include decreased blood flow from dehydration or heart failure.
• Intra-renal causes involve damage to kidney tissue, such as acute tubular necrosis and glomerulonephritis.
• Post-renal causes arise from urinary obstruction, e.g., kidney stones or tumors.
• Common symptoms: oliguria (low urine output) or anuria (no urine output), edema, electrolyte imbalances, nausea, and vomiting.
• Diagnosis performed through serum creatinine and blood urea nitrogen (BUN) tests, urinalysis, and imaging (ultrasound or CT).
• Management focuses on treating the underlying cause, fluid management, and medications like diuretics.

Chronic Renal Failure (CRF)

• Gradual and often irreversible decline in kidney function.
• Major causes include diabetes mellitus, hypertension, chronic glomerulonephritis, and polycystic kidney disease.
• Symptoms may include fatigue, anemia, hypertension, altered urine output, and electrolyte imbalances.
• Progresses through five stages based on Glomerular Filtration Rate (GFR):
  • Stage 1: Normal GFR (≥ 90 mL/min) with mild damage.
  • Stage 2: Mild GFR decrease (60-89 mL/min).
  • Stage 3: Moderate GFR decrease (30-59 mL/min).
  • Stage 4: Severe GFR decrease (15-29 mL/min).
  • Stage 5: Kidney failure (GFR < 15 mL/min).
• Management strategies include controlling blood sugar and hypertension, dietary changes, and renal replacement therapy (dialysis or transplantation).

Dialysis

• A therapeutic procedure that eliminates waste products and excess fluids when kidneys fail.
• Hemodialysis filters blood via a machine, typically administered three times weekly.
• Peritoneal Dialysis utilizes abdominal lining for blood filtration and can be performed at home.
• Indications for dialysis include severe electrolyte imbalances, fluid overload, acidosis, and uremic symptoms such as nausea and fatigue.
• Possible complications involve infection at access sites, hypotension, anemia, and bone disease.

Complications of Renal Failure

• Cardiovascular Issues: Hypertension, heart failure, and heightened risk of cardiovascular diseases.
• Electrolyte Imbalances: Conditions like hyperkalemia (high potassium), hyperphosphatemia (high phosphate), and hypocalcemia (low calcium).
• Metabolic Disorders: Metabolic acidosis and uremia, reflecting waste accumulation in the bloodstream.
• Bone and Mineral Disorders: Osteodystrophy leading to bone pain and fractures, and calciphylaxis characterized by small blood vessel calcification.
• Anemia: Results from decreased erythropoietin production.
• Infections: Increased risk due to immune system impairment and dialysis-related access points.