Introduction to Renal Disease Flashcards
What is the equation for GFR?
GFR = (UCr x UVol)/PCr
What are the problems with the GFR equation?
- Can only be used reliably in patients with stable renal function
- May be less accurate in certain populations
• High/normal/near normal renal function
• Children
• Certain ethnic groups
• Pregnant women
• Unusual muscle mass, body habitus, or weight
What is the use of fractional Na excretion in the assessment of renal disease?
It is measured in terms of plasma and urine sodium, rather than by the interpretation of urinary sodium concentration alone, as urinary sodium concentrations can vary with water reabsorption. Therefore the urinary and plasma concentrations of sodium must be compared to get an accurate picture of renal clearance.
Why is fractional urea excretion better to use than fractional Na excretion?
FE of urea is useful no matter what the range of values is while FE of Na is not helpful between 1-2%
What is normal urine output?
1500 mL/24 hours
Azotemia
Elevation in nitrogen containing compounds in the plasma and usually indicates renal problems
Uremia
Clinical syndrome that can accompany kidney failure, usually when advanced and/or severe due to an elevated level of urea.
Oliguria
Little urine output 500mL/day
Polyuria
High urine output 3000mL/day
Anuria
No urine output
AKI
Acute Kidney Injury
CKD
Chronic Kidney Disease
ESRD
End Stage Renal Disease
How is AKI defined?
An abrupt (within 48 hours) reduction in kidney function, defined as:
• ↑ in serum creatinine of > 0.3mg/dL OR
• Percentage ↑ in serum creatinine of 50% OR
• Oliguria of 6 hours
How is CKD defined?
- Progressive decline in GFR over time
- Duration at least three months
- With or without albuminuria
