This test measures the amount of chloride in the blood or serum. Chloride is one of the important chemicals that is found in the body. Changes in chloride levels in the blood are often similar to changes in sodium levels. This is true because sodium and chloride are often linked together in the body.

Who is a candidate for the test?

If a doctor suspects one of the conditions that result from too high or too low a level of chloride, he or she may order this test.

How is the test performed?

A sample of blood is taken from a vein on the forearm or hand. First, the skin over the vein is cleaned with an antiseptic such as alcohol. Next, a rubber tube called a tourniquet is tied around the upper arm. This restricts blood flow in the lower arm veins and causes them to enlarge. And that makes them easier to see and insert a needle into. A fine needle is inserted into the vein, and the tourniquet is then untied. Blood flows from the vein through needle into a vial. After the needle is withdrawn from the vein, the puncture site is covered with a bandage.