SO2 in a blood test refers to oxygen saturation, which measures the percentage of hemoglobin in your blood that's carrying oxygen. This crucial indicator reflects how efficiently your blood is transporting oxygen throughout your body.
How is SO2 Measured?
Oxygen saturation (SO2 or sO2) can be determined in a couple of ways:
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Arterial Blood Gas (ABG) Test: This involves taking a blood sample from an artery and analyzing it in a lab to measure the levels of oxygen and carbon dioxide, along with the blood's pH. This provides a precise measurement of SO2. [See references: Arterial Blood Gas (ABG): What It Is, Purpose, Procedure & Levels; ABG (Arterial Blood Gas) | Lab Tests | GLOWM; Arterial Blood Gas (ABG) Test: MedlinePlus Medical Test; Blood gases Information | Mount Sinai - New York]
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Pulse Oximetry: This non-invasive method uses a sensor placed on your finger or earlobe to measure the light absorption by oxygenated and deoxygenated hemoglobin. This gives a continuous, albeit less precise, reading of SO2. [See references: Oxygen saturation (sO2) - Radiometer; Oxygen saturation: normal values & measurement - cosinuss°; Oxygen saturation (SO2) measures the percentage of hemoglobin which is fully combined with oxygen. While this measurement can be obtained from an arterial or venous blood sample, its major attractive feature is that it can be obtained non-invasively and continuously through the use of a "pulseoximeter"; Low blood oxygen (hypoxemia) - Mayo Clinic; How to.. interpret blood gas results — Veterinary Internal Medicine ...]
What Does SO2 Tell Us?
A low SO2 level (hypoxemia) indicates that your blood isn't carrying enough oxygen, which can be a sign of various respiratory or circulatory problems. Conversely, a high SO2 level isn't typically a problem in itself, although it might point to other underlying conditions needing investigation. A normal SO2 level is generally above 95% when measured from an arterial blood sample. [See references: Oxygen saturation (sO2) - Radiometer; How to.. interpret blood gas results — Veterinary Internal Medicine ...]
It's important to note that SO2 is just one piece of the puzzle in diagnosing medical conditions. Your doctor will use this information alongside other tests and symptoms to reach a complete diagnosis.
