Whether you’re going to see your doctor for a routine checkup or are admitted to the hospital, your doctor needs information about how your body is functioning. A basic metabolic panel is a combination of tests that helps your doctor assess important functions in your body.
The tests that make up the basic metabolic panel are blood (serum) tests for:
BUN (blood urea nitrogen)
This test measures the amount of nitrogen in the blood.
CO2 (carbon dioxide or bicarbonate)
This test references lung and kidney function.
Creatinine levels can tell your doctor how your kidneys are functioning.
A glucose test checks your blood sugar levels—abnormally high or low glucose levels could indicate a range of issues.
This test determines if the concentration of sodium is within normal limits. It is part of your electrolyte panel.
Your potassium levels are tested as part of your electrolyte panel .
Testing for the calcium levels in your blood can help determine if there is a kidney, bone, or nervous system problem.
Chloride levels are checked as part of your electrolyte panel.
A few laboratories also include tests for albumin, which tests blood protein levels to test for kidney and liver disease.
The basic metabolic panel can give your doctor a good idea if you have any serious problems with:
- blood filtration
- acid/base balance of your blood
- blood sugar levels
- electrolyte levels
This can help uncover kidney problems, lung problems, certain heart problems, and problems with your pancreas or insulin metabolism. More detailed tests will be ordered if any of these basic indicators are abnormal.
One advantage of a panel of tests is that many tests can be done with just one blood sample that is divided up in a lab.
A small amount of your blood is needed to perform this panel of tests. The blood sample is obtained through “venipuncture.” A needle is inserted into a vein in your arm or hand. Blood is drawn through the needle into a tube and analyzed in a laboratory.
You will need to fast for eight hours before you have your blood drawn for this test. Do not eat and take only small sips of water.
You may also have to stop taking certain medications before the test is performed, but only if your doctor tells you to do so. Do not stop taking medication unless your doctor tells you to stop.
When the blood is collected, you may feel some moderate pain or a mild pinching sensation. After the needle is removed, you may feel a throbbing sensation. You will be instructed to apply pressure to the site where the needle entered your skin. A bandage will be applied and will need to remain in place for 10 to 20 minutes to stop any bleeding. You should avoid using that arm for heavy lifting for the rest of the day.
There are some very rare risks involved in taking a blood sample, including:
- lightheadedness or fainting
- hematoma (a bruise where blood accumulates under the skin)
- infection (usually prevented if the skin is cleaned before the needle is inserted)
- excessive bleeding (bleeding for a long period after the test may indicate a more serious bleeding condition and should be reported to your doctor)
- Blood Urea Nitrogen (BUN): 7-20 mg/dL (milligrams per deciliter of blood)
- Creatinine: 0.8-1.4 mg/dL
- Serum Sodium (Na+ ): 136-144 mEq/L (milliequivalents per liter of blood)
- Serum Potassium (K+): 3.7-5.2 mEq/L
- Serum Calcium: 8.5-10.2 mg/dL (milligrams per deciliter)
- Serum Chloride (Cl-): 101-111 mmol/L (millimoles per liter)
- Serum carbon dioxide/bicarbonate (CO2): 20-29 mmol/L
- Glucose: 64-128 mg/dL (milligrams per deciliter of blood)
- Albumin: 3.4-5.4 g/dL (grams per deciliter of blood)
Abnormal test results may indicate a serious medical condition, such as kidney disease, diabetes, or lung disease.
A high BUN level may indicate kidney diseases, such as glomerulonephritis or kidney failure. Other possible causes include congestive heart failure or hypovolemic shock. A low BUN level may point to liver problems, insufficient protein in your diet, or drinking too much water.
High serum sodium may be due to various hormonal diseases, such as diabetes insipidus or Cushing syndrome. It may also mean too much sodium in the diet, excessive sweating, or the use of certain diuretics. A lower-than-normal sodium level may also be due to hormonal abnormalities, such as Addison’s disease or SIADH (syndrome of inappropriate hormone secretion). Low sodium may also be due to dehydration, vomiting, and certain kinds of heart failure.
High serum potassium is often an indication of kidney disease. Potassium is very important for muscle function. High potassium levels can decrease heart muscle activity. Low serum potassium may be due to the use of diuretic medications or certain hormonal problems. Low levels can cause an irregular heartbeat.
High serum calcium can be caused by problems with the parathyroid gland, taking too many calcium supplements, or certain types of cancer. Low serum calcium levels can be caused by an inactive parathyroid gland, kidney or liver failure, vitamin D deficiency, or problems with your pancreas.
High chloride levels may indicate metabolic acidosis, where the kidneys are not removing enough acid from the body. Low chloride levels may be due to Addison’s disease, congestive heart failure, or dehydration. Metabolic alkalosis and a number of other abnormalities affect chloride levels as well.
High bicarbonate or carbon dioxide levels may be caused by breathing problems, Cushing syndrome, or hormonal problems. Lower-than-normal levels can be caused by acidosis, kidney disease, or several kinds of poison toxicities.
Fasting blood glucose levels help to diagnose diabetes or prediabetes. A blood glucose level of 100-125 mg/dL after fasting may indicate that you are at risk for developing diabetes. You are diabetic if you have a fasting blood glucose over 126 mg/dL. Other problems, such as hyperthyroidism and certain kinds of pancreatic cancers involve high blood glucose. Low blood glucose may indicate an underactive pituitary gland or thyroid gland. Low glucose can also occur when a diabetic consumes too much insulin or too little food.
High levels of albumin are very rare. Low albumin levels may be due to kidney or liver disease, recent weight-loss surgery, or a low protein diet.
These are all brief summaries of possible causes for abnormal test results. Talk to your doctor about each specific test in detail to learn more about what abnormal levels may indicate.