Arterial gasometry is a blood test that is normally performed on people admitted to an intensive care unit, which aims to verify that the gas exchange is being performed correctly and therefore assess the need for additional oxygen.
In addition, it is an examination that can be requested during hospitalization to assist in the diagnosis of respiratory, renal or severe infections, as well as to check if the treatment is effective and can therefore be used as one of the criteria that can influence the patient’s discharge.
- Arterial blood gas test is done by taking a blood sample from the artery in your arm or leg.
- This type of collection is quite painful.
- As it is a more invasive collection.
- The collected blood is transported to the laboratory for biochemical tests to check blood pH.
- Bicarbonate concentration and partial CO2 pressure.
Arterial gasometry should not be used for peripheral artery disease, as there may be difficulty in blood draw, bleeding problems or if the person is using blood thinners. In such cases, your doctor may order more tests to identify diseases that cause respiratory changes.
Your doctor asks for arterial blood gases to
In addition, a blood gas test is also required in case of overdose. This test is not common, it is not done in a clinic or a routine consultation, being requested by the doctor only in more severe cases.
Normal values for arterial blood gas tests are:
An analysis of arterial blood gases indicates how the lung works, i.e. whether gas exchanges are performed smoothly, indicating the condition of the person, which may be respiratory or metabolic acidosis or alkalosis. Understand what metabolic and respiratory acidosis, metabolic alkalosis and respiratory alkalosis mean.
The following table presents some examples of modified values of arterial blood gases:
This test is not enough to close the diagnosis, it only suggests respiratory, renal or metabolic disorders, and other complementary tests, such as X-rays, CT scans, other blood tests and urine tests, are usually requested by the doctor so that the diagnosis can be closed and treatment can be initiated as the cause of the change in blood gas testing.
Arterial gasometry determines the exact values of the amount of oxygen and whether the kidneys and lungs are functioning properly, which helps in the diagnosis of lung, kidney and infectious diseases.
Venous blood gas testing, on the other hand, is performed as a second option when artery sampling is not possible, the sample is taken from the vein, and its main goal is to help diagnose peripheral arterial diseases or blood clotting problems. .