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Bicarbonate or total CO2 (HCO3-) is part of the metabolic or electrolyte panels that monitors or identifies acid-base (pH) or electrolyte imbalance. The bicarbonate test measures the total amount of carbondioxide (CO2) in the blood, which is mostly occurring as HCO3-. HCO3- measurement during an electrolyte panel can help diagnose alkalosis or acidosis – abnormal conditions resulting from an imbalance in the blood pH from excess alkali (base) or acid. Underlying diseases or conditions can cause acid-base imbalance.

What does the bicarbonate test measure?

The bicarbonate-carbonate acid buffer is an important buffer system in the body that help maintain normal body fluid and blood acid-base (pH) balance. Bicarbonate is a negatively charged iron in the body that helps maintain the acid-base balance. It works with other electrolytes (chloride, potassium and sodium) to ensure cells are electrically neutral.

The bicarbonate test measures the total amount of CO2 in the blood, occurring as HCO3-. Carbondioxide is the main by-product of different metabolic processes. The test gives your healthcare professional the average estimate of acid-base balance. This test alone may be sufficient, but you may need to measure dissolved gasses in the blood (blood gases) to get more information.

Most times, HCO3- measurement is alongside potassium, sodium and sometimes chloride in an electrolyte panel because the balance of these molecules gives the healthcare professional adequate information.

When do I need the bicarbonate test?

You undergo the bicarbonate test during your routine health check-up. Your healthcare professional may also order the test if they suspect alkalosis or acidosis or when you have symptoms of an acute condition such as;

You may need regular electrolyte testing if you have a condition or disease or taking a medication that affects your electrolyte balance.

Bicarbonate testing

A bicarbonate test is part of a blood test; the blood sample is from a vein in your arm.

Bicarbonate test results

Conditions that cause low bicarbonate levels to include:

Conditions that result in high bicarbonate levels include:

When you get your bicarbonate test result, we advise asking your doctor the following questions.

If you need a bicarbonate test, contact Private Blood Tests London on 020 71830244 to schedule an appointment for your test.

Frequently asked questions

How can I get the total CO2 test?

The total CO2 test is usually part of an electrolyte panel test. An electrolyte panel test is available at the Private Blood Tests London.

How much is the test?

A bicarbonate test done during an electrolyte panel test is routine blood work. It is an affordable test that costs below £40. Your health insurance can also cover part of the full cost of the test.