Blood Tests

One of the most familiar of all diagnostic tools, blood tests involve taking a sample of blood from the patient, then analyzing it in a lab. Tests can measure the amount of various substances in the blood, such as chemicals, harmful microorganisms (such as bacteria), antibodies (which may mean a virus is present) and the different types of blood cells. Your baby or child's doctor will decide which tests need to be run on your child's blood sample.

Common tests include:

• Blood typing—to check the blood group (A, B, O) and the Rh factor (positive or negative)
• Measurement of blood gasses—levels of oxygen, carbon dioxide, and acid
• Measurement of blood sugar level
• Measurement of electrolyte levels
• Testing for anemia (too few red blood cells) or polycythemia (too many red blood cells)
• Testing for infection in the blood, urine, or spinal fluid