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Health Information For Teens
A blood test is when a sample of blood is taken from the body to be tested in a lab. Doctors order blood tests to check things such as the levels of glucose, hemoglobin, or white blood cells. This can help them detect problems like a disease or medical condition. Sometimes, blood tests can help them see how well an organ (such as the liver or kidneys) is working.
The comprehensive metabolic panel (CMP) is a blood test that gives doctors information about the body’s fluid balance, levels of electrolytes like sodium and potassium, and how well the kidneys and liver are working.
A CMP is done to learn information about the levels of:
You may be asked to stop eating and drinking for 8 to 12 hours before a CMP. Tell your doctor about any medicines you take because some drugs might affect the test results. Wearing a T-shirt or short-sleeved shirt can make things easier for you on the day of the test.
Most blood tests take a small amount of blood from a vein. To do that, a health professional will:
Collecting a sample of blood is only temporarily uncomfortable and can feel like a quick pinprick.
Parents usually can stay with their child during a blood test. Try to relax and stay still because tensing muscles can make it harder to draw blood. You might want to look away when the needle is inserted and the blood is collected. Try taking slow deep breaths or singing a favorite song to help you relax.
Most blood tests take just a few minutes. Occasionally, it can be hard to find a vein so the health professional may need to try more than once.
The health professional will remove the elastic band and the needle and cover the area with cotton or a bandage to stop the bleeding. Afterward, there may be some mild bruising, which should go away in a few days.
Blood samples are processed by a machine, and it may take a few hours to a day for the results to be available. If the test results show signs of a problem, the doctor might order other tests to figure out what the problem is and how to treat it.
A comprehensive metabolic panel is a safe procedure with minimal risks. Some teens might feel faint or lightheaded from the test, and a few have a strong fear of needles. If you’re anxious, talk with the doctor before the test about ways to make the procedure easier.
A small bruise or mild soreness around the blood test site is common and can last for a few days. Call your doctor if the discomfort gets worse or lasts longer.
If you have questions about the CMP, speak with your doctor or the health professional doing the blood draw.
This common blood test helps doctors gather information about a person’s blood cells and how they’re working. Find out why doctors do this test and what’s involved for teens.
This test measures the speed at which red blood cells fall to the bottom of an upright glass test tube. Find out why doctors do it and what’s involved for teens.
A magnesium test looks at levels of the mineral magnesium in a person’s blood. Find out why doctors do this test and what’s involved for teens.
A phosphorus test looks at levels of phosphorus in a person’s blood. Find out why doctors do this test and what’s involved for teens.
Need to get a blood test? An MRI? These videos show what happens in 10 of the most common medical tests.
These videos show what’s involved in getting a blood test and what it’s like to be the person taking the blood sample.
If your liver isn’t working properly, it can affect your overall health. Find out why doctors do liver function tests and what’s involved for teens.
A basic metabolic panel (BMP) is a group of blood tests that provide doctors with clues about how the body is working. Find out why doctors do this and what’s involved for teens.
The kidneys perform several functions that are essential to health, the most important of which are to filter blood and produce urine.
Visit our Cancer Center for teens to get information and advice on treating and coping with cancer.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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