Total CO2 or bicarbonate is different than the partial pressure
of CO2 (PCO2). Learn about PCO2 At a Glance Why Get Tested? When
to Get Tested? During a routine physical or as recommended by
your doctor if you are experiencing symptoms such as weakness,
confusion, prolonged vomiting, or respiratory distress that
could indicate an electrolyte imbalance or acidosis or alkalosis
A blood sample drawn from a vein in the arm Test Preparation
Needed? The Test Sample What is being tested? The total CO2 test
measures the total amount of carbon dioxide in the blood, which
occurs mostly in the form of bicarbonate (HCO3-). Bicarbonate is
a negatively charged ion that is excreted and reabsorbed by the
kidneys. It is used by the body to help maintain the body's
acid-base balance (pH) and secondarily to work with sodium,
potassium, and chloride to maintain electrical neutrality at the
cellular level. How is the sample collected for testing? A blood
sample is drawn by needle from a vein in the arm. NOTE: If
undergoing medica