Blood gas tension
Blood gas tension refers to the
Oxygen tension
- Arterial blood oxygen tension (normal)
PaO2 – Partial pressure of oxygen at sea level (160
- Venous blood oxygen tension (normal)
PvO2 – Oxygen tension in venous blood at sea level is between 30 mmHg and 40 mmHg.[6][7]
Carbon dioxide tension
Carbon dioxide is a by-product of food metabolism and in high amounts has toxic effects including:
- Arterial blood carbon dioxide tension
PaCO2 – Partial pressure of carbon dioxide at sea level in arterial blood is between 35 mmHg and 45 mmHg.[9]
- Venous blood carbon dioxide tension
PvCO2 – Partial pressure of carbon dioxide at sea level in venous blood is between 40 mmHg and 50 mmHg.[9]
Carbon monoxide tension
- Arterial carbon monoxide tension (normal)
PaCO – Partial pressure of CO at sea level in arterial blood is approximately 0.02. It can be slightly higher in smokers and people living in dense urban areas.
Significance
The partial pressure of gas in blood is significant because it is directly related to
3 (and lactate) suggest to the health care practitioner which interventions, if any, should be made.[10][11]
Equations
Oxygen content
The constant, 1.36, is the amount of oxygen (ml at 1 atmosphere) bound per gram of
Oxygen saturation
This is an estimation and does not account for differences in temperature, pH and concentrations of 2,3 DPG.[13]
See also
- Alveolar air equation
- Fick's laws of diffusion
- Fraction of inspired oxygen