Kidney Blood Test Preparation. This test shows how well your kidneys are working the normal value for gfr is 90 or above. You can and should eat and drink the same as you do normally to get an accurate result.
The blood test is called the glomerular filtration rate. Therefore if you have an abnormal result you may need further tests to find the cause of a kidney problem. This is known as your gfr glomerular filtration rate.
Kidney function tests usually require a 24 hour urine sample and a blood test.
Your physician can determine if you should wait 24 to. Blood is drawn and collected into a plain. It gives your doctor an idea of how much. Urine tests other blood tests scans x rays kidney biopsy etc.