PaO2/PAO2

PaO2/PAO2 is a test that measures how much oxygen your red blood cells are carrying in partial pressure of oxygen (PaO₂). This measures the presence of oxygen that’s dissolved in your blood. The partial pressure means the pressure of a single gas component in a mixture of gases.

The PaO₂ shows the capability of the lungs to diffuse O₂ from the Alveoli of the Lungs into the circulating blood. It is used to measure how active the lungs are to oxygenate the blood. It also evaluates the effectiveness of oxygen therapy.

Purpose Of PaO2/PAO2 Test:

The PaO₂ test can be used to assess the effect of breathing problems on oxygen supply, especially in a hospital setting or during episodes of severe reparatory distress. PaO₂ value can also be used (along with other tests) to help diagnose conditions or events.

• Chest or Lung trauma
• Chronic lung disease such as Asthma
• Obstructive pulmonary disease (COPD)
• Congestive Heart Failure
• Heart Attack
• Loss of Consciousness
• Sudden shortness of breath

Causes OF High (PaO₂):

• Polycythemia
• Pain and discomfort
• High Dose of oxygen
• Throbbing or slight bruising

Causes OF Low (PaO₂):

• Chronic obstructive pulmonary disease
• Emphysema
• Pulmonary embolism
• Pulmonary Edema
• Low Atmospheric oxygen
• Hypoventilation
• Cardiac Decompensation
• Pneumonia

How The Test is Performed:

Usually, blood is taken from an artery In some cases, blood from a vein may be used (venous blood gas).

• Radial artery in the wrist
• The femoral artery in the groin
• The brachial artery in the arm

Risk OF PaO₂:

There is little risk when the procedure is done correctly. Veins and Arteries vary in size from one person to another & person from one side of the body to the other. Taking blood from some people may be more difficult them from others.

• Fainting or feeling lightheaded
• Multiple punctures to locate blood vessels
• Hematoma
• Excessive bleeding
• Infection (a slight risk any time the Skin is broken)

Normal Range of (PaO2):

Abnormal Results:

Abnormal results may be due to lungs, kidneys, metabolic diseases, or medicines. Head or neck injuries or other injuries that affect breathing can also lead to abnormal results.

Procedure:

• There is no special preparation. If you are on Oxygen therapy, the oxygen concentration must remain constant for 20 minutes before the test.
• If you are taking any blood-thinning medicines (anticoagulants), including Aspirin, warfarin, etc.
• Collect the 2ml arterial blood or Venous blood in a heparinized syringe, or Green top Tube with sodium heparin or lithium Heparin.
• Mix the sample immediately Stability of the Sample at room temperature is 30 minutes.
• The stability of is crushed ice container is 1 hour.

Result:

• Partial pressure of oxygen (PaO₂): 75 to 100mmHg or 10.5 to 13.5 kilopascal (kPa).
• Normal Ranges may vary slightly among different laboratories.