Blood gas tension Blood gas tension Blood gas tension refers to the partial pressure of gases in blood. There are several significant purposes for measuring gas tension; the most common gas tensions measured are oxygen tension (PO), the carbon dioxide tension (PCO) and carbon monoxide tension (PCO). The subscript "x" in each symbol represents the source of the gas being measured; ""a"" meaning arterial, ""A"" being alveolar, ""v"" being venous, ""c"" being capillary. Blood gas tests (such as arterial blood gas tests) measure these partial pressures. PO – Partial pressure of oxygen at sea level (765 mmHg) in arterial blood is between 75
Hemoglobin Hopkins-2 carboxyl group of the amino acid forms a hydrogen bond with phenolix hydroxyl, which in turn stabilizes the structure of the molecule and increases oxygen affinity. Ho-2 hemoglobin has high levels of oxygen, which replaces the lack of oxygen within red blood cells. Ho-2 is similar to Hemoglobin A, which is normal hemoglobin and also contains two α-chains. This provides an explanation as to how the Hopkins-2 variant of hemoglobin is related to the symptoms of sickle cell. Hopkins-2 can also interact specifically with Hemoglobin S. Hemoglobin S is the most common abnormal hemoglobin variant. Hemoglobin S is the variant