GFR and Creatinine Flashcards
What is GFR?
It is the rate at which fluid filters into the Bowman’s capsule. 20% of cardiac output.
What is GFR dependent on?
Renal blood flow. If you have good blood flow, you have good GFR. Anything that affects the blood flow (cardiac output) affects the functioning of the GFR.
What is normal GFR?
125 ml’s per minute
What is creatinine a measurement for?
It is an indirect measurement of GFR
What is creatinine clearance a measurement for?
More precise measurement for GFR
What is normal creatinine clearance?
90 & 125 ml’s per minute
Where is creatinine synthesized?
Mainly in the skeletal muscles.
Where is creatinine excreted?
The kidneys using glomerular filtration.
What do increased levels of creatinine indicate?
Decreased renal function.
What measurement indicates renal insufficiency?
An increase of creatinine by 0.3 to 0.5 mg/day.
What is the ratio of creatinine to renal loss?
Every time creatinine doubles, there is a 50% renal loss.
What is the renal function if the creatinine is 1.0?
100% renal function
What is the renal function if the creatinine 2.0?
50%
In the elderly, what is the significance of serum creatinine?
Does not reflect renal function due to the decrease in muscle mass?
What is the renal function if the creatinine is 3.0?
25% renal function
