Acute Renal Failure and Chronic Kidney Disease - Chapter 28

This set of flashcards covers essential vocabulary related to Acute Renal Failure and Chronic Kidney Disease, providing definitions of terms crucial for understanding renal function and associated diseases.

Acute Renal Failure (ARF)

An abrupt reduction in renal function producing an accumulation of waste materials in the blood.

Oliguria

A condition defined by a low output of urine, often associated with acute renal failure.

Glomerular Filtration Rate (GFR)

A measure of how well the kidneys filter blood, often used to assess kidney function.

Blood Urea Nitrogen (BUN)

A test that measures the amount of urea nitrogen in the blood, indicating renal function.

Azotemia

An increase in the blood urea nitrogen (BUN) level as a result of impaired renal function.

Prerenal Failure

A type of acute renal failure due to conditions that impair renal blood flow, characterized by low GFR and high urine specific gravity.

Postrenal Failure

A type of acute renal failure caused by obstruction within the urinary collecting system distal to the kidney.

Intrarenal Failure

A type of acute renal failure resulting from primary dysfunction of the nephrons, often seen in acute tubular necrosis.

Chronic Renal Failure (CRF)

The irreversible loss of renal function that affects nearly all organ systems, commonly resulting from conditions like diabetes and hypertension.

Stages of Chronic Kidney Disease

Classified based on nephron loss and GFR levels; includes stages from normal function (Stage 1) to end-stage renal disease (Stage 5).

Uremic Syndrome

A clinical condition resulting from the retention of metabolic waste products due to renal failure.

Fluid Overload

A condition that can develop in acute renal failure where the kidneys cannot remove sufficient fluid, leading to swelling and hypertension.

Nephrotoxin

Any substance that is harmful to the kidneys, often leading to acute renal failure.

Metabolic Acidosis

A condition characterized by a decrease in blood pH due to an accumulation of acid or loss of bicarbonate, common in renal failure.

Renal Osteodystrophy

A bone disease related to chronic renal failure, caused by alterations in calcium and phosphorus metabolism.

Diuresis

Increased production of urine; can occur during the recovery stage of acute tubular necrosis.

Anemia

A common complication of chronic renal failure, often due to lack of erythropoietin.

Electrolyte Imbalance

Disruption in normal levels of electrolytes such as sodium, potassium, and phosphorus, which can occur in renal failure.

Therapeutic Interventions

Strategies aimed at managing chronic kidney disease, including blood glucose control and dietary modifications.

Prerenal Acute Renal Failure

Caused by impaired renal blood flow (hypovolemia, hypotension, heart failure); Decreased GFR, oliguria, high specific gravity, low urine sodium, signs of fluid overload.

Postrenal Acute Renal Failure

Due to obstruction (stones, tumors, prostate); Findings vary by obstruction duration; Leads to increased Bowman capsule pressure and decreased GFR.

Intrarenal Acute Renal Failure

Caused by primary nephron damage (most commonly ATN); Shows isosthenuria, granular casts, and inability to concentrate urine.

Acute Tubular Necrosis (Oliguric Stage)

1-2 weeks; Oliguria, increased BUN/Cr, fluid overload, hyperkalemia, metabolic acidosis.

Acute Tubular Necrosis (Diuretic Stage)

2-10 days; Increased urine output, but kidneys cannot concentrate; Continued azotemia; Risk of dehydration + electrolyte loss.

Acute Tubular Necrosis (Recovery Stage)

Last months; Gradual normalization of BUN/Cr; Residual renal insufficiency may remain.

Fractional Excretion of Sodium (FENa)

Calculated measure that differentiates prerenal (<1%) from intrinsic (>2%) renal failure.

Decreased Renal Reserve

Up to 75% nephron loss; Labs normal; Asymptomatic

Renal Insufficiency

75-90% nephron loss; Mild azotemia; Polyuria and nocturia.

End-Stage Renal Disease (ESRD)

90% nephron loss; Severe azotemia; Fluid/electrolyte imbalances; Uremia; Bone disease; Anemia.

Hyperphosphatemia

Occurs due to decreased phosphate excretion; Leads to hypocalcemia.

Hypocalcemia

Due to decreased vitamin D activation and calcium binding with phosphate.

Secondary Hyperparathyroidism

Parathyroid hormone (PTH) increases to compensate for low calcium and high phosphate.

Renal Osteodystrophy

Bone demineralization due to calcium/phosphate imbalance and high PTH.

Metabolic Acidosis in CKD

Kidneys lose ability to secrete H+ and regenerate bicarbonate.

Hypertension in CKD

Caused by fluid overload, RAAS activation, and increased sympathetic nervous system (SNS) activity.

Anemia in CKD

Due to decreased erythropoietin production.

Uremic Syndrome - Key Manifestations

Encephalopathy, pericarditis, neuropathy, pruritus, uremic frost, nausea, vomiting, bleeding tendency, impaired immunity.

ARF Prevention

Maintain fluid status + cardiac output; Avoid nephrotoxins; Treat infections early.

ACE Inhibitors/Angiotensin II Receptor Blockers (ARBs) in CKD

Used to reduce proteinuria and slow progression.

Nutritional Management in CKD

Restrict protein, potassium, phosphorus, sodium; Increase calories; Supplement calcium + vitamins.

Dialysis Indications

Used for severe uremia, electrolyte disturbances, volume overload, or or end-stage renal disease (ESRD).