Acute Kidney Injury

Question 1

Normal GFR and their decline with age.

Answer 1

125 ml/min
10% decrease after age 30
decrease in GFR of 7-10ml/min per decade after age 40

Question 2

Normal specific gravity

Answer 2

1.001 - 1.022

indicates how concentrated the urine is.

Question 3

BUN : Creatinine ratio

Answer 3

Normal 10 : 1
If 10 : 1 - 20 : 1 may indicate volume depletion, decreased perfusion, excessive protein intake.
In ATN ratio increases proportionately maintain 10:1 (40:4; 60:6)

Question 4

Normal Serum osmolality

Answer 4

280-300 mOsm/kg
Decrease serum osmolarity is usually d/t decrease serum Na.
Increased serum osmolarity can occur d/t increase Na, uric, glucose, waste products

Question 5

Normal Urine osmolality

Answer 5

300-900 mOsms/kg/24hrs
If it is the same as serum osmolality the kidney is unable to concentrate urine.
In renal disease one of the first function to be lost is the contraction of urine
Urine osmolality reflects dilution

Question 6

Define Azotemia

Answer 6

Increase in BUN, creatinine and a reduction in excretion of Na (less than 20mEq/L)

Question 7

Define Oliguric Phase

Answer 7

Urine output

Question 8

Define Non-Oliguia

Answer 8

Elevated BUN and creatinine
Urine output > 400ml/day
Hyperkalemia
Faster healing process

Question 9

Define Anuria

Answer 9

Urine output

Question 10

Define Diuretic Phase, the risk factors, and the goal

Answer 10

Beginning of recovery
Gradual increase in UO (excessive UO)
Ability to concentrate urine is still impaired
Risk for fluid volume deficit, hyponatrema, and hypokalemia.
Maintain hydration and prevent electrolyte balance

Question 11

Define Recovery Phase

Answer 11

GFR increases

BUN and creatinine level plateau and then decrease (do not increase anymore)

Question 12

Management of hyperkalemia

Answer 12

Regular insulin and glucose moves K back into the cell
Na Bicarbonate can correct metabolic acidosis and moves K back into the cell.
Calcium Gluconate raises the threshold for excitability for myocardium decreases dysrhythmias.
Hemodialysis is the most effective way to remove K
Sodium Polystryren Sulfonate (kayexalate)

Question 13

Dietary restriction for AKI patients

Answer 13

Moderate protein intake; restrict K, Na, and phospate.
Increase CHO intake.
Fluid restriction 600ml + UO of the last 24hrs.

Question 14

What is used to differentiate oliguria associated with AKI from other pre-renal causes (hypo perfusion)?

Answer 14

Urine Sodium test

Poor renal perfusion = less Na in the urine 30 mEq/L

Question 15

What is the most precise test in predicting tubular injury?

Answer 15

Fraction excretion of Na test

Serum Na and urine Na are measured simultaneously

Question 16

Most common causes of AKI in older adults

Answer 16

Dehydration 
Hypotension 
Diuretic therapy
Aminoglycoside therapy
Obstruction disorder
Surgery
Infection 
Radiocontrast agent