Acute Kidney Injury part 1

Question 1

Epidemiology

Answer 1

Approximately < 1% outpatients, 20% hospitalized patients, 50% critically ill patients

In developed countries: older population with complex disease processes

In developing countries: younger population with single or simple disease processes

Question 2

suseptabilities

Answer 2

Advanced age
Black race
Female sex
Hypovolemia

Question 3

exposures

Answer 3

Critical illness
Circulatory shock
Sepsis
Trauma
Burns

Question 4

acute kidney injury definition

Answer 4

↑ SCr by ≥ 0.3 mg/dL within 48 hours

	OR

↑ SCr to ≥ 1.5 x baseline within 7 days

	OR

↓ UOP to < 0.5 mL/kg/hr for 6 hours

Question 5

presentation

Answer 5

Asymptomatic
Functional signs and symptoms
-Fluid overload
-Electrolyte accumulation
-Uremia
Cause-specific signs and symptoms

Question 6

prerenal aki (acute kidney injury)

Answer 6

Hypovolemia or effective hypovolemia

Medications (NSAIDs, ACE, ARB

Elevated renal venous pressure

Question 7

Intrinsic Vascular AKI

Answer 7

Small vessel disease

Large vessel disease

Question 8

Intrinsic Glomerular AKI

Answer 8

Idiopathic

Medications

Systemic rheumatologic disease

Paraneoplastic syndrome

Question 9

Intrinsic Tubular-Interstitial AKI

Answer 9

Acute tubular necrosis (ATN)

• Ischemia (insufficient oxygen supplies to tissues)
• Medications
• Sepsis

Acute interstitial nephritis (AIN) - medication use

Cast or crystalline nephropathy

Urate or phosphate nephropathy

Question 10

postrenal aki

Answer 10

malignancy, prostate disease

Question 11

prerenal indication

Answer 11

Normal urine sediment

Fractional excretion of sodium < 1%, urine sodium < 20 mEq/L

Responsive to fluids

BUN/SCr > 20

Oliguria

Question 12

common

Answer 12

Tachycardia, dry mucus membranes, decreased skin turgor, cool extremities, orthostatic hypotension, sunken eyes

Edema, ascites

Abdominal distension

Question 13

acute tubular necrosis indications

Answer 13

Muddy brown and granular epithelial cell casts and free epithelial cells in urine sediment

Fractional excretion of sodium > 2%, urine sodium > 40 mEq/L (FENa)

Unresponsive to fluids

BUN/SCr 10 to 15

Oliguria or nonoliguria

Question 14

if you attempt to correct hypovalemia after giving fluid and the patient does have a response,

Answer 14

(increase in urine output and decrease in serum creatinine)

they have prerenal aki. if no response, then acute tubular necrosis.

Question 15

glomerular disease

nephritic pattern

Answer 15

RBC, WBC, and RBC casts in sediment

Variable proteinuria

Hypertension

Systemic inflammation

Question 16

glomerular disease

nephrotic pattern

Answer 16

Bland sediment

Massive proteinuria

Hypoalbuminemia

Edema

Question 17

Acute Interstitial Nephritis

Answer 17

Rash

Fever

Eosinophilia

WBC, RBC, and WBC casts in sediment (sterile pyuria)

Question 18

Urgent Renal Replacement Therapy

Answer 18

Severe metabolic acidosis (pH < 7.1) with hypervolemia

Severe hyperkalemia (K+ > 6.5 mEq/L)

Pulmonary edema

Uremic encephalopathy, seizures, or pericarditis

Question 19

management of complications

Answer 19

Volume abnormalities

• Fluids for volume depletion
• Loop diuretics for volume overload

Electrolyte imbalances, especially hyperkalemia and hyperphosphatemia

Acid-base disturbances, especially metabolic acidosis