Search results
Results from the WOW.Com Content Network
An arterial blood gas (ABG) test, or arterial blood gas analysis (ABGA) measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a syringe and a thin needle , [ 1 ] but sometimes the femoral artery in the groin or another site is used.
A blood gas test or blood gas analysis tests blood to measure blood gas tension values, it also measures blood pH, and the level and base excess of bicarbonate.The source of the blood is reflected in the name of each test; arterial blood gases come from arteries, venous blood gases come from veins and capillary blood gases come from capillaries. [1]
Venous blood with an oxygen concentration of 15 mL/100 mL would therefore lead to typical values of the a-vO 2 diff at rest of around 5 mL/100 mL. During intense exercise, however, the a-vO 2 diff can increase to as much as 16 mL/100 mL due to the working muscles extracting far more oxygen from the blood than they do at rest. [citation needed]
Normal arterial blood oxygen saturation levels in humans are 96–100 percent. [1] If the level is below 90 percent, it is considered low and called hypoxemia . [ 2 ] Arterial blood oxygen levels below 80 percent may compromise organ function, such as the brain and heart, and should be promptly addressed.
Acid–base and blood gases are among the few blood constituents that exhibit substantial difference between arterial and venous values. [6] Still, pH, bicarbonate and base excess show a high level of inter-method reliability between arterial and venous tests, so arterial and venous values are roughly equivalent for these. [44]
Venous blood is typically colder than arterial blood, [1] and has a lower oxygen content and pH. It also has lower concentrations of glucose and other nutrients and has higher concentrations of urea and other waste products. The difference in the oxygen content of arterial blood and venous blood is known as the arteriovenous oxygen difference.
Blood gas tension refers to the partial pressure of gases in blood. [1] There are several significant purposes for measuring gas tension. [ 2 ] The most common gas tensions measured are oxygen tension (P x O 2 ), carbon dioxide tension (P x CO 2 ) and carbon monoxide tension (P x CO). [ 3 ]
Using the fact that each gram of hemoglobin can carry 1.34 mL of O2, the oxygen content of the blood (either arterial or venous) can be estimated by the following formula: = [] ( /) + PO2 is the partial pressure of oxygen and reflects the amount of oxygen gas dissolved in the blood. The term 0.0032 * P02 in the equation is very small and ...