Glomerular filtration rate (GFR)

Definition

Glomerular filtration rate (GFR) is a measure of the rate at which blood is filtered through the glomeruli of the kidneys. It is an essential indicator of kidney function and overall renal health.

5 Must Know Facts For Your Next Test

1. GFR is typically measured in milliliters per minute (mL/min) and indicates how much blood passes through the glomeruli each minute.
2. Normal GFR values range from 90 to 120 mL/min, with lower values indicating potential kidney dysfunction.
3. GFR can be estimated using equations that take into account serum creatinine levels, age, sex, and body size.
4. Chronic Kidney Disease (CKD) stages are classified based on GFR values, with stage 1 being normal/high function and stage 5 indicating kidney failure.
5. Factors such as dehydration, acute illness, or medications can temporarily affect GFR readings.

Review Questions

• What does a low GFR value indicate about kidney function?
• Which factors are taken into account when estimating GFR using equations?
• How is Chronic Kidney Disease (CKD) staged based on GFR?

Related terms

Kidney Filtration: The process by which the kidneys filter blood to remove waste products and excess substances.

Creatinine Clearance: A test used to estimate GFR by measuring the amount of creatinine cleared from the blood by the kidneys.

Nephron: The functional unit of the kidney responsible for filtering and excreting waste products from the blood.