2 English reference blood gas analysis [2 1 century bilingual dictionary of science and technology]
Summary Blood gas analysis is to analyze the gas stored in human blood, which can directly reflect the pulmonary ventilation function and its acid-base balance. The indexes of blood gas analysis are oxygen, carbon dioxide and acid-base balance.
4 name blood gas analysis
5 indications for blood gas analysis are applicable to:
1. Diagnosis of hypoxemia and respiratory failure.
2. Differential diagnosis of dyspnea.
3. Differential diagnosis of coma.
4. Selection of surgical indications.
5. Use, adjustment and removal of ventilator.
6. Observe respiratory therapy.
7. Diagnosis of acid-base imbalance.
6 contraindications There are no special contraindications.
Seven test blood samples
8 test method blood gas analysis
9 laboratory category blood biochemical examination > blood gas analysis
10 Prepare to fill in the application form, including the patient's name, hospitalization number, ward bed number, blood collection date, blood collection place, oxygen concentration, hemoglobin content and body temperature, so as to correct the blood gas analysis data.
1 1 method11.1. Collect blood sample (1), and take the patient lying or semi-sitting position. Make necessary explanations to patients and ask them to cooperate.
(2) Extract 0.5ml heparin with a concentration of 1000U/ml from a blood sampling syringe or a special arterial puncture blood sampling syringe, and follow the operation instructions.
(3) Pulse cutting to find the puncture point. Usually the puncture sites are radial artery, brachial artery, femoral artery and dorsal foot artery.
(4) Hold the syringe in one hand and feel the arterial pulse in the other hand to accurately find out the puncture artery. The insertion site of the skin needle should be on the arterial line 5 mm away from the pulse. Insert the needle gradually until you see blood entering the needle core. Take enough blood (2 ~ 3ml for adults, 0.5 ~ 1ml for children and 0.2ml for infants), then discharge air bubbles, puncture the 5min plug with a puncture needle to isolate the air, cover it with sterile gauze, and press the puncture site for at least 5 minutes.
(5) Turn the syringe to make the blood mix evenly, put the name tag on it, put the blood sampling syringe in the curling, and immediately send it to the blood gas analysis laboratory (the arterial blood sample should be placed for no more than 65438±00min at room temperature and no more than 65438±0h in 4℃ ice water, and the blood gas index will not change much).
1 1.2 2. Determination method (1) Immediately detect blood samples.
(2) Gently rub the needle tube by hand to make the blood fully mixed and then eliminate the air bubbles.
(3) Open the injection port, advance the blood sample, and then input the corresponding data.
(4) After the results are printed, post them on the application form and report them immediately.
1 1.3 3. Quality control (1) Conduct 1 quality control every month according to the conventional method.
(2) After replacing the electrode or repairing the instrument, timely control the quality 1 time.
1 1.4 4. Calibration (1) Calibration shall be conducted once every 1 hour and twice every two hours.
(2) After replacing the electrode sleeve, the corresponding calibration should be carried out.
1 1.5 5. Flushing After each measurement (including calibration), the instrument will automatically flush the measuring chamber and pipeline. Rinse the measuring room and pipeline with deproteinized liquid 1 every day.
12 the collection technology of preventive measures specimens is closely related to the accuracy of test results. The collection methods and precautions of blood gas analysis specimens are as follows.
1. Blood collectors should be able to master the collection technology of arterial blood gas samples.
2. When drawing blood, the patient should be in a quiet and stable breathing state, and the blood drawing time should be on an empty stomach in the morning or 2 hours after meals. Due to the excitement of vagus nerve after meals, the role of carbonic anhydrase in gastric mucosa is strengthened, and gastric parietal cells divide into H+ in gastric juice, and a large amount of HCO3-enters the blood, which is called "alkaline tide". If blood is drawn at this time, it will affect the test results.
In addition, the patient's temperature and hemoglobin concentration have a certain influence on the results, so the patient's temperature and hemoglobin concentration should be measured in advance before blood collection.
3. The superficial arteries with more collateral circulation should be selected for blood collection, such as radial artery, brachial artery or femoral artery. It is forbidden to use pressure bandage when taking blood, otherwise it will affect the accuracy of the results.
4. Blood collection equipment Because air can pass between the syringe and the plug of a disposable syringe and the friction is large, blood cannot enter the syringe by itself during blood collection, so you should choose an autoclaved glass syringe or a special blood gas collection tube.
5. Heparin sodium is used as anticoagulant during blood collection. After heparin fully infiltrated the inner wall of the syringe, air and excess heparin sodium were discharged, and the amount of blood collected was 2 ~ 3 ml. The dilution ratio of heparin in blood should be less than 5%, otherwise it will lead to low pH value, low PCO2 and high PO2, among which the decrease of PCO2 is the most obvious. After the blood collection is completed, the needle should be inserted into the rubber plug immediately to seal the needle, otherwise the gas will increase the pH value, lower the PCO2 and higher the PO2.
It depends. Some people learn from scratch, which takes a long time; And some people themselves have a certain foundation, which can be mastered qu