Half-saturated oxygen partial pressure (P50)

P50 refers to the partial pressure of oxygen when hemoglobin is 50% saturated. It reflects the ability of blood to transport oxygen and the affinity of hemoglobin for oxygen. Decrease: The oxygen shift curve shifts to the left, the affinity of oxygen and hemoglobin increases, and it is easy to combine oxygen, and it is not easy to release oxygen, thereby making the tissue hypoxic. Basic Information Specialist classification: growth and development examination classification: blood examination Applicable gender: whether men and women apply fasting: not fasting Tips: Ensure that the needle and needle of the syringe are tightly coupled and there must be no air leaks. Normal value Normally, when pH = 7.40 and PaCO2 = 5.33 kPa (40 mmHg), P50 was 3.54 kPa (26.6 mmHg). Clinical significance 1. Reduce the oxygen shift curve to the left, increase the affinity of oxygen and hemoglobin, easily combine oxygen, and not easily release oxygen, thus making the tissue hypoxic. 2. The oxygen shift curve is shifted to the right, the affinity between oxygen and hemoglobin is lowered, and oxygen is easily released, so that the oxygen content of the tissue is high. Low results may be diseases: chronic obstructive pulmonary disease considerations 1. Conventional arterial blood should be taken for examination. If venous blood is to be taken, the forearm should be immersed in 45 °C warm water for 20 minutes to make the venous blood arterial. It is not advisable to use a tourniquet when drawing blood. 2. Flush with heparin beforehand in the syringe; 3. Ensure that blood specimens are not in contact with the outside air; 4. Send samples in time; 5, certain drugs can affect the pH of the blood, the doctor should be informed of the recent medication before the test. Inspection process Same as oxygen electrode assay. Not suitable for the crowd no. Adverse reactions and risks no.