Wk. 11 - Acute Kidney Injury Flashcards

What are the primary functions of the kidney?

Filtration, electrolyte balance, acid-base balance, blood pressure regulation, erythropoiesis, and vitamin D metabolism.

How do the kidneys contribute to blood pressure regulation?

By producing renin, which activates the renin-angiotensin-aldosterone system (RAAS).

What hormone is secreted by the kidneys to stimulate red blood cell production?

Erythropoietin.

What is the active form of vitamin D produced by the kidneys?

Calcitriol.

How do the kidneys maintain acid-base balance?

By regulating bicarbonate reabsorption and hydrogen ion excretion.

What are the three classifications of acute kidney injury (AKI)?

Prerenal, intrarenal, and postrenal.

What is the most common cause of prerenal AKI?

Hypovolemia (e.g., dehydration, blood loss).

What laboratory finding is characteristic of prerenal AKI?

Increased BUN/Creatinine ratio (>20:1).

What are common causes of intrarenal AKI?

Nephrotoxins (drugs, contrast dye), ischemia, glomerulonephritis, and acute tubular necrosis.

What urine finding is suggestive of acute tubular necrosis?

Muddy brown casts.

What is the primary cause of postrenal AKI?

Obstruction (e.g., kidney stones, enlarged prostate, tumors).

What are common symptoms of postrenal AKI?

Anuria or fluctuating urine output, pain, and hydronephrosis on imaging.

What are the three stages of AKI according to KDIGO classification?

Stage 1: 1.5–1.9x increase in creatinine or ≥ 0.3 mg/dL rise; Stage 2: 2.0–2.9x increase; Stage 3: ≥ 3x increase or ≥ 4.0 mg/dL.

How is fluid balance managed in AKI?

Monitor intake/output, restrict fluids in overload, and use diuretics if needed.

How is hyperkalemia treated in AKI?

Calcium gluconate, insulin/glucose, sodium bicarbonate, and dialysis if severe.

What dietary restrictions are recommended for patients with AKI?

Low potassium

Name nephrotoxic medications that should be avoided in AKI.

NSAIDs, ACE inhibitors, ARBs, contrast dye, aminoglycosides, amphotericin B.

When is dialysis indicated in AKI?

Severe metabolic disturbances, fluid overload, or persistent uremia.

What defines chronic kidney disease (CKD)?

GFR < 60 mL/min/1.73m² for ≥ 3 months or evidence of kidney damage (proteinuria, hematuria, structural damage).

What are the leading causes of CKD?

Diabetes mellitus and hypertension.

How does CKD affect electrolyte balance?

Causes hyperkalemia, hyperphosphatemia, and hypocalcemia.

What bone disease is associated with CKD?

phosphorus metabolism.

Why does anemia occur in CKD?

Due to decreased erythropoietin production.

What dietary modifications are recommended for CKD patients?

Low sodium, potassium, phosphorus, and protein (unless on dialysis).

How is hypertension managed in CKD?

ACE inhibitors or ARBs.

What medications are used to manage anemia in CKD?

Erythropoiesis-stimulating agents (ESAs) and iron supplements.

What drugs are used to manage CKD-MBD?

Phosphate binders, vitamin D supplements, and calcimimetics.

What is the goal of fluid management in CKD?

Sodium restriction and diuretics for fluid overload.

What medications should be avoided in CKD due to nephrotoxicity?

NSAIDs, contrast dye, aminoglycosides, cyclosporine, and vancomycin.

What are the two types of dialysis?

Hemodialysis and peritoneal dialysis.

What is a major complication of hemodialysis?

Hypotension and dialysis disequilibrium syndrome.

What is a major risk of peritoneal dialysis?

Peritonitis.

What dietary restrictions apply to patients on hemodialysis?

Low phosphorus, potassium, and fluid restriction.

Why is protein intake increased for patients on dialysis?

To compensate for protein losses during dialysis.

What is uremic frost?

Crystallized urea on the skin due to severe CKD.

What is the first-line treatment for hyperkalemia in CKD?

Potassium binders like sodium polystyrene sulfonate (Kayexalate).

How does CKD contribute to cardiovascular disease?

Through hypertension, hyperlipidemia, and vascular calcification.

What is the purpose of a fistula in dialysis patients?

To provide vascular access for hemodialysis.

What is the primary indication for kidney transplantation?

End-stage renal disease (ESRD) with irreversible kidney failure.