Alternate Names : Serum Creatinine, Serum Creatinine Level, Creatinine Level in the Blood
Creatinine is a waste product made by the body during
regular metabolism. It is excreted into the urine by the kidneys. A
serum creatinine test measures the level of creatinine in the blood.
The level of creatinine in the blood is a good measure of
overall kidney function. When the kidneys are not working well for
any reason, they are not able to excrete creatinine into the urine.
When this happens, the level of creatinine in the blood rises.
Who is a candidate for the test?
Doctors may order this test when they think a person is
or has kidney damage. This test may also be ordered before or after a
doctor prescribes certain medicines. The main reason to order the
test is to make sure the kidneys are working well.
How is the test performed?
To perform a serum creatinine test, a blood sample is
taken from a vein on the forearm or hand. First, the skin over the
vein is cleaned with an antiseptic. Next, a strong rubber tube called a
tourniquet is wrapped around the upper arm. This enlarges the veins
in the lower arm by restricting blood flow through them. A needle is
gently inserted into a vein, and the tourniquet is removed. Blood flows
from the vein through the needle, and is collected in a syringe or vial.
After the needle is withdrawn, the puncture site is covered with a
bandage for a short time to prevent bleeding. The blood sample is
sent to the laboratory to determine the amount of creatinine circulating
in the blood.