Serum Chloride

Alternate Names
chloride

Definition of Serum Chloride

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 chloride, which has a negative electrical charge, balances sodium, which has a positive electrical charge, in most body fluids.

Who is a candidate for the test?

If a healthcare professional 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, causing them to enlarge.

A fine needle is inserted into the vein, and the tourniquet is then untied. Blood flows from the vein through the needle into a vial. After the needle is withdrawn from the vein, the puncture site is covered with a bandage.

What is involved in preparation for the test?

No preparation is generally needed for this test.

What do the test results mean?

Normal values for the total amount of chloride in the blood range from 98 to 106 mEq/L (milliequivalents per liter).

Chloride can become too high because of conditions including:

• dehydration
• conditions causing excessive urination
• severe vomiting or diarrhea
• severe burns

Many things can cause the chloride to become too low including:

• diuretics, also called water pills
• kidney disease
• uncontrolled diabetes
• congestive heart failure
• cirrhosis of the liver
• very high protein, triglycerides, or glucose in the blood