It is a measurement of the amount of oxygen and carbon dioxide present in the blood. This test also determines the acidity (pH) of the blood. To determine these values, it is necessary to examine the blood of an artery.
For this study no special preparation is required. You can eat before the survey and drink and take any medicine.
A lab technician or doctor will take some blood from an artery. Most of the times from the radial artery of the wrist or the femoral artery in the groin or the elbow artery. This exam is similar to a regular blood test with the only difference being that the location of entrée of the needle has to be compressed for some time. A pressure bandage or plaster is applied to the spot and must remain there for half an hour to an hour, this also depending on the medications you are using. Sometimes this test is repeated before and after oxygen inhalation. The duration of the examination is approximately 45 minutes.