Whether you’re going to see your doctor for a routine checkup or you’re 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 them assess important functions in your body.
The tests that make up the basic metabolic panel are blood (serum) tests for:
- BUN (blood urea nitrogen), which measures the amount of nitrogen in the blood in order to determine your kidney function
- creatinine, which can tell your doctor how your kidneys are functioning
- glucose, which checks your blood sugar levels — abnormally high or low glucose levels could indicate a range of issues
- albumin, which is a protein that can change with kidney and liver disease
- CO2 (carbon dioxide or bicarbonate), which references lung and kidney function
- calcium, which can help determine if there is a kidney bone or parathyroid problem (a gland in the neck)
- sodium, one of the salts in the body that reflects more the body’s water balance than salt
- potassium, another salt in the body
Your sodium, potassium, and chloride levels will be tested as part of your electrolyte panel. Electrolyte balance is essential to the normal functioning of the muscular, cardiovascular, and nervous systems.
The basic metabolic panel can give your doctor a good idea as to whether you have any serious problems with:
- blood filtration
- acid/base balance of your blood
- blood sugar levels
- electrolyte levels
This can help uncover a variety of medical issues, including:
- kidney problems
- lung problems
- 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. It’s then 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 do not need to do anything special before this test and should not stop taking medication unless your doctor tells you to.
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’ll 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, which is usually prevented if the skin is cleaned before the needle is inserted
- excessive bleeding for a long period after the test, which may indicate a more serious bleeding condition and should be reported to your doctor
Normal ranges will vary slightly for adults over the age of 60 years.
|Test||Normal range (adults 18-60 years old)||Normal range (adults over 60 years old)||Category|
|BUN (blood urea nitrogen)||6-20 mg/dL (milligrams per deciliter of blood)||8-23 mg/dL||kidney test|
|creatinine||0.9-1.3 mg/dL for men; 0.6-1.1 mg/dL for women||0.8-1.3 mg/dL for men; 0.6-1.2 mg/dL for women||kidney test|
|glucose||70-99 mg/dL||70-99 mg/dL||sugar metabolism|
|albumin||3.4-5.4 g/dL (grams per deciliter of blood)||3.4-5.4 g/dL||blood protein|
|CO2 (carbon dioxide or bicarbonate)||23-29 mEq/L (milliequivalent units per liter of blood)||23-31 mEq/L (adults 61-90 years old); 20-29 mEq/L (adults over 90 years old)||electrolyte panel|
|Ca+ (calcium)||8.6-10.2 mg/dL||8.6-10.2 mg/dL||electrolyte panel|
|Na+ (sodium)||136-145 mEq/L||132-146 mEq/L (adults over 90 years old)||electrolyte panel|
|K+ (potassium)||3.5-5.1 mEq/L||3.5-5.1 mEq/L||electrolyte panel|
|Cl- (chloride)||98-107 mEq/L||98-111 mEq/L (adults over 90 years old)||electrolyte panel|
Abnormal test results may indicate a serious medical condition, such as kidney disease, diabetes, or lung disease.
A high BUN level may indicate kidney disease, such as glomerulonephritis or kidney failure. Other possible causes include congestive heart failure or hypovolemic shock. Steroids can increase your BUN, as can bleeding. A low BUN level may point to liver problems or insufficient protein in your diet.
A high creatinine level may also indicate kidney problems, muscle disease, or preeclampsia. A low creatinine level may be due to muscular dystrophy or myasthenia gravis, a rare disorder.
Fasting blood glucose levels may help to diagnose diabetes. You may have diabetes if your fasting blood glucose is 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 or thyroid or adrenal gland. Low glucose can also occur when a person with diabetes consumes too much insulin or other diabetic medications, or eats too little food while taking these medications.
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.
High bicarbonate or carbon dioxide levels may be caused by breathing problems, metabolic problems, Cushing’s syndrome, or hormonal problems. Lower-than-normal levels can be caused by acidosis, kidney disease, or several kinds of poison toxicities.
High serum calcium can be caused by problems with the parathyroid gland most commonly, or certain types of cancer. Low serum calcium levels can be caused by many conditions, including:
- an inactive parathyroid gland
- kidney or liver failure
- vitamin D deficiency
- problems with your pancreas
High serum sodium may be due to various hormonal diseases, such as diabetes insipidus or Cushing’s syndrome. 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 heart, liver, or kidney failure.
High serum potassium is often an indication of kidney disease. Potassium is very important for muscle function. High potassium levels can cause problems with the electrical activity of the heart. Low serum potassium may be due to the use of diuretic medications or certain hormonal problems. Low levels can cause an irregular heartbeat.
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.
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.