blood oxygen content

Oxygen content refers to the content of oxygen in the blood under the condition of blood and air isolation, including physical dissolution and chemical combination, reflecting the actual content of oxygen in the blood sample. The amount of oxygen dissolved is affected by PO2, and the oxygen partial pressure of 0.13 kPa can dissolve 0.03 ml/L of oxygen. Under normal circumstances, the dissolved oxygen is only 3ml / L, the amount is very small, the actual measured blood oxygen content is hemoglobin-bound oxygen. Blood oxygen levels are determined by the hemoglobin content and the degree of binding between them. Basic Information Specialist classification: Respiratory examination classification: pulmonary function test Applicable gender: whether men and women apply fasting: not fasting Tips: Before taking blood, please indicate whether you are taking oxygen. The blood specimen should be isolated from the outside air and sent to the test in time. Normal value Arterial blood 150 ~ 230ml / L; venous blood 110 ~ 180ml / L. Different parts, venous blood oxygen content can be very different. The arterial blood oxygen content of the same person is about 50 ml/L higher than the venous blood oxygen content, and the male is higher than the female. Clinical significance Blood oxygen content refers to the total amount of oxygen in the blood, including the total amount of physical dissolution and oxygen binding to hemoglobin. Reduced blood oxygen levels: may be insufficient total hemoglobin (anemia), or may be caused by decreased oxygen saturation or decreased PO2. Conversely, normal blood oxygen levels do not rule out tissue hypoxia. Increasing PO2 can increase the amount of oxygen dissolved, such as hyperbaric oxygen chamber treatment, can increase the dissolved oxygen to 30 ~ 50ml / L. Arterial blood and venous blood oxygen levels are reduced in various types of anemia, thin air, insufficient oxygen supply, respiratory pressure or obstruction, pneumonia, pulmonary edema and right to left shunt congenital heart disease; venous blood oxygen content is reduced in local Blood stasis, shock, heart failure, etc. When cyanide is poisoned, the venous blood oxygen content may not decrease due to a decrease in tissue oxygen uptake capacity. When the arteriovenous fistula is sputum, its blood oxygen content increases toward the heart. In patients with giant limbs, the blood oxygen content of the affected limbs is significantly higher than that of normal limbs. At the time of cardiac catheterization, since the blood of the superior vena cava comes from the head and upper limbs, the oxygen content is lower than that of the lower limb blood, which may be 10 to 30 ml/L, and the oxygen content of the coronary sinus is the lowest; There is a laminar flow, so the oxygen content of each part of the right ventricle is different. The normal difference is: the difference between the right atrium and the superior vena cava is less than 19ml / L; the difference between the right atrium and the right ventricle is less than 9ml / L; the difference between the pulmonary artery and the right ventricle is less than 5ml / L. If the difference exceeds this limit, there may be a left-to-right shunt in the heart, so this difference can be used as a basis for the diagnosis of congenital heart disease such as atrial septal defect, ventricular septal defect and patent ductus arteriosus. Low results may be diseases: simple pulmonary stenosis in children, pediatric respiratory failure, primary-pulmonary septal defect, congenital subaortic stenosis, shock, pediatric atrial septal defect, atrial septal defect, pediatric patent ductus arteriosus, congenital coronary Arterial fistula, ventricular septal defect precautions (1) Before the blood is drawn, it is necessary to indicate whether or not to take oxygen. The blood sample should be isolated from the outside air and sent to the test in time. Arterial blood gas analysis of blood collection sites, generally the radial artery, radial artery, femoral artery and so on. If venous blood is required, the forearm should be placed in warm water at 45 ° C for 20 min to make the venous blood arterial. It is not advisable to use a tourniquet when drawing blood. (2) The use of certain drugs can increase or decrease the pH of the blood, such as the use of sodium bicarbonate, ethenic acid, sodium glutamate, phenylbutazone, aspirin, etc. to increase blood pH; use tetracycline, isoniazid Bismuth, phenformin, ammonium chloride can reduce blood pH. Inspection process Same as oxygen electrode assay. Not suitable for the crowd Generally there are no special taboos. Adverse reactions and risks 1. It may cause certain damage to the blood vessels. 2, blood draw has the potential to cause infection.