Lab Tests|Why Are They Sticking That Needle In Your Arm?

What are the top labs and why do you need them?

So you go to the doctor and he orders some lab tests. Maybe you are feeling a bit sluggish and tired and he wants to see what is going on. You agree, but have no clue why you are getting stuck in the arm with that needle or why they are drawing fourteen thousand jiggers of blood out of you! Here’s a low down on some of the most common tests and why you would get them:

  * ESR is the sedimentation rate to determine the presence of infections, tumors, inflammation, degenerative tissues & organs and also can monitor the progress of disease or the effect of therapy.

In other words, it is a test to determine the degree of inflammation present in your body. The reason you would get this test is if the doctor thinks you may have one of the conditions above or to monitor the course of rheumatoid arthritis or rheumatica. The test results don’t tell you where in the body the inflammation is or what is causing it, it is usually in conjunction with some other tests. It is usually ordered when a condition is suspected of causing inflammation in the body, like arthritis.

    * CMP is a comprehensive metabolic panel. It is a group of 14 specific, standardized tests that will give the doctor vital information about the current status of your kidneys, liver, blood sugar, blood proteins, electrolytes and acid balance. I won’t go into detail of each test, however, you could say it is a broad screening tool to evaluate the function of your organs and to check for disease of the liver and kidneys. It can also be ordered to monitor hypertension and to check for diabetes. You will usually have to fast for 1-12 hours before this test. It is mostly a routine work up for your annual exam. The results won’t usually tell you what is wrong, you will most likey have to follow up with other tests if there is anything abnormal.

    * CBC is a Complete Blood Count test. This is done to determine your general health and also to screen for disorders like anemia. It is a count of the cells in the blood, including the number of white blood cells, red blood cells, hemoglobin content, hematocrit and more. Abnormalties may require a blood smear under a microscope to determine anything more.

The reason the doctor may order a BMP is if you have fatigue or weakness, an infection, inflammation or bruising or bleeding.

    * BMP is a test that measures your sugar or glucose level, your electrolyte and fluid balance and your kidney function. Here’s a quick rundown of things: your glucose is a sugar the body uses for energy. Electrolytes keep the body’s fluids in balance and working normally and the kidney’s function is to filter out waste and substances that are not needed from the blood. By taking any type of medications like diuretics for high blood pressure, the doctor could order a BMP just to see if the medicine is affecting things. Usually you will be asked to fast about 10-12 hours before the test.

    * BNP is a very important test. It will diagnose the presence of heart failure. Higher than normal results will determine if a person is in heart failure.

    * PREALBUMIN is a test to determine if someone is at risk for poor nutrition or is malnourished. Prealbumin is a protein produced by the liver. Protein deficiencies can affect the bodies ability to heal and fight infections.

    * PSA is a prostate test to screen men for prostate cancer. If a man has painful, difficult or frequent urination, the doctor may order a PSA. The PSA is a protein that is produced by cells in the prostate gland. This test can also be ordered to screen someone with prostate cancer.

    * CK Profile is a test to decide if you have had a heart attack or if other muscles in your body had been damaged. The test is called Creatine and is from an enzyme found in the heart, brain, skeletal muscles and other tissue. Blood levels rise when muscle or heart cells are injured. If you have chest pain or signs of a heart attack, the doctor may order a CK.


These are some of the more common tests that are done  in a doctor's office or at a lab. It is my hope that breaking them down for you makes it easier to understand just what exactly some of these blood tests are and why we need them. Arm yourself with knowledge so the next time you are told you need some lab work done, you will know why those needles are getting poked in your arm!