Patient education: Comprehensive metabolic panel (The Basics)

What is a comprehensive metabolic panel? — A comprehensive metabolic panel ("CMP") is a type of blood test. It measures the levels of certain substances in the body. "Panel" means multiple tests are done on the same blood sample. It is sometimes called a "CHEM-12" or "CHEM-14," depending on how many different tests are included.

A CMP usually measures:

●Blood glucose – This is also known as blood sugar.

●Calcium – This is a mineral the body needs for the bones, muscles, and heart to be healthy.

●Electrolytes – These are minerals and other substances that the body needs to work properly. They include sodium, potassium, chloride, and bicarbonate.

●Blood urea nitrogen ("BUN") and creatinine – These are waste products created when the kidneys filter blood.

●Protein – Protein helps muscles stay strong. The CMP measures the total protein and a specific type of protein called albumin.

●Alkaline phosphatase ("ALP"), alanine aminotransferase ("ALT"), and aspartate aminotransferase ("AST") – These are substances in the liver that help it break things down.

●Bilirubin – This is a substance created as red blood cells are broken down. It passes through the liver before leaving the body.

A CMP can show if you have too much or too little of any of these substances in your blood. This can be a sign of a medical problem.

Why might I get a CMP? — You might get a CMP as part of a regular check-up or if your doctor suspects that you have a health problem. If you have a long-term or "chronic" problem, your doctor might also do a CMP to monitor your condition. Examples of chronic health problems include kidney disease and high blood pressure.

A CMP can help your doctor or nurse check for:

●Diabetes or prediabetes – "Prediabetes" is when a person's blood sugar is higher than normal, but not high enough to be called diabetes.

●Certain medical conditions – Different conditions can cause calcium or electrolyte levels to be too high or too low.

●Problems with how well your kidneys or liver are working

●Signs that medicines you are taking are not working properly

Based on the results of your CMP, your doctor or nurse will decide if you need other tests or treatment.

How do I prepare for a CMP? — For this test, you will need to get a "blood draw." Your doctor or nurse will tell you where to go for this. They might tell you to avoid eating or drinking for 8 to 12 hours before the test.

It might help to wear a short-sleeve shirt when you get your blood drawn. This makes it easier for the person drawing the blood to get to your arm.

What happens during a blood draw? — For a blood draw, a needle is used take a small amount of blood from your arm (figure 1). Collecting the blood only takes a few minutes. The blood is then tested in a lab.

Tell the person who takes your blood:

●If you take "blood thinner" medicines or if you have a bleeding problem – They will make sure that your bleeding is under control before you leave.

●If you have a latex allergy – Some of the supplies used for blood draws might contain latex.

●If you have a preferred arm to use

Most of the time, getting blood taken does not cause problems. You might have a little soreness or bruising where the needle went in.

What do my results mean? — Your doctor or nurse will tell you when to expect your results, and will contact you with the results. Or if you use an online "patient portal," you might get an alert there when your results are ready.

If your CMP shows any abnormal results, your doctor or nurse will talk to you about what to do next. They might need to do more tests to figure out what the cause is.

If you do have a health problem, your doctor will work with you to come up with a plan for treatment.

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Patient education: Basic metabolic panel (The Basics)