Cerebrospinal fluid partial pressure of oxygen (PO2) and carbon dioxide (PCO2)

Cerebrospinal fluid oxygen partial pressure (PO2) refers to the strong physical dissolved oxygen in the cerebrospinal fluid, which reflects the degree of hypoxia in the brain. Carbon dioxide partial pressure (PCO2), also known as carbon dioxide, refers to the pressure generated by the cerebrospinal fluid to dissolve carbon dioxide. Basic Information Specialist classification: examination classification: cerebrospinal fluid examination Applicable gender: whether men and women apply fasting: fasting Analysis results: Below normal: PO2 reduction is seen in cerebral hypoxia and cerebral ischemia. Normal value: GSF-PCO2: 5.3-5.9kPa GSF-PO2: 5.9-6.7kPa Above normal: Elevated PCO2 is seen in acidosis. negative: Positive: Tips: Electrode standardization must be very reliable, otherwise it will cause a lot of errors. Normal value PO25.3 to 5.9 kPa (40 to 44 mmHg). PCO 25.9 to 6.7 kPa (44 to 50 mmHg). Clinical significance (1) PO2 reduces cerebral hypoxia and cerebral ischemia. (2) PCO2 raises acidosis. Low results may be diseases: high results of cerebral ischemic diseases may be diseases: precautions for respiratory acidosis (1) The PO2 electrode film (polypropylene film) should be replaced periodically according to the requirements of the instrument performance indicators used, and the electrode buffer should be refilled at the same time. If the ratio of the water mark to the gas mark reading is greater than 0.96 to 1.0, the film should be considered defective. (2) Electrode standardization must be very reliable, otherwise it will cause a large error. Inspection process Specimens stored in low temperature must be reached at 37 °C after being injected into the measurement chamber. Some modern instruments have temperature indicators, and the specimens are automatically indicated after reaching 37 °C. Air bubbles must be vented in the measurement chamber or it can cause a large error. PO2 measurement results should be temperature corrected. If the patient's body temperature deviates from 37 °C during collection, the corrected PO2 (kPa) value can be obtained according to the following formula. The formula is: PO2 (T ° C) = [PO2 (37 ° C) × 100.031 (T-37)]. Not suitable for the crowd 1. If there is obvious papilledema or cerebral palsy, contraindications are contraindicated. 2. Patients who are in shock, exhaustion or endangered state and local skin inflammation, and lesions in the posterior cranial fossa are contraindicated. Adverse reactions and risks If the patient has symptoms such as breathing, pulse, or abnormal color during puncture, stop the operation immediately and deal with it accordingly.