bronchoalveolar lavage (BAL)

Bronchoalveolar lavage (BAL) is performed by fiberoptic bronchoscopy on the lung segment or sub-segment of the lower bronchi, repeatedly sterilized and recovered by sterile saline, and subjected to a series of tests and analysis to obtain the characteristics of lower respiratory tract lesions. The characteristics and level of activity help to establish a diagnosis. Basic Information Specialist Category: Respiratory Examination Category: Other Inspections Applicable gender: whether men and women apply fasting: fasting Tips: Actively cooperate with the doctor during the examination. Normal value normal. Clinical significance Indications: Pulmonary infections, especially immunopathy, pathogenic diagnosis of immunodeficiency lung infections, cytological diagnosis of diffuse and peripheral lung tumors, interstitial lung disease such as sarcoidosis, idiopathic pulmonary stroma Diagnosis, treatment, efficacy, and prognosis of fibrosis, exogenous allergic alveolitis, alveolar proteinosis, collagen vascular with pulmonary fibrosis, etc. A series of techniques for cytology, biochemistry, enzymology and immunology of the recovered liquid by repeated techniques of diarrhea and recovery of sterile saline by fiberoptic bronchoscopy at the level of the lung or sub-pulmonary segments below the bronchi. And analysis. 1. Whole lung lavage for the treatment of alveolar proteinosis, silicosis, alveolar microlithiasis, asthma status, etc. 2. Lung lavage is mainly used for the diagnosis of diffuse interstitial pulmonary fibrosis, asbestosis and Pneumocystis carinii pneumonia, and is also of great value in the diagnosis of diffuse alveolar carcinoma. Precautions 1, strict control of indications, elderly, body failure patients should be monitored by electrocardiogram and percutaneous blood oxygen saturation. Intraoperative administration of nasal catheter oxygen or high frequency ventilation for oxygen. 2, strict aseptic operation during surgery to prevent secondary infection. 3, according to the requirements of regular operation, qualified lavage fluid should reach the specified recovery, no mixed blood (red blood cell count <10%), should not be mixed with a large number of epithelial cells (<3%). 4. Send the test as soon as possible after obtaining the lavage fluid. 5, after the onset of fever, bleeding, lung infection, bronchospasm and other complications, the corresponding treatment. Inspection process Check operation 1. Fasting 3-4 hours before surgery. 30 minutes before surgery, intramuscular injection of diazepam (diazepam) 10mg and atropine 0.5mg. 2, 2% lidocaine nasal mucosa, local airway mucosal anesthesia. 3, fiberoptic bronchoscopy through the nasal cavity inserted into the trachea, embedded in the right middle lobe or left lung tongue bronchial orifice (localized lung lesions should be selected corresponding bronchoalveolar segment), after injection of 2% lidocaine 2-3ml local anesthesia, with The 50 ml syringe was injected with 37 ° C physiological saline in several portions, each time 25-50 ml total amount 100-300 ml, and immediately after the injection, it was sucked by the vacuum suction device and recovered into the silicon lavage fluid collection bottle. Generally, the amount of recovered liquid should be 40%-60% of the amount of the injected liquid. 4. The recovered liquid is filtered with double-layer sterile gauze to remove the mucus. The total amount of recovered liquid is recorded, placed in a siliceous container, placed in ice water (-4 °C) and sent to the inspection room. The irrigation should be carried out within 2-3 hours. The lotion is inspected and analyzed. Bronchoalveolar lavage cytology (1) Total number and classification of BALF cells 1 The above-mentioned recovery lavage solution was placed in a plastic centrifuge tube at 1200 r/min, centrifuged at 4 ° C for 10 min, and the supernatant (stock solution or 10 times concentrated) was stored at -70 ° C for use as a soluble component. 2 The cell fraction precipitated by centrifugation was washed twice with Hank's solution (without Ca2+, Mg2+) under the same conditions for 5 min each time. Discard the supernatant and add 3 to 5 ml of Hank solution to prepare a cell suspension. Cellulite can also be used to reduce cell loss. 3 The total number of cells in the BALF was then counted on a modified Neubauer counter, generally expressed as 1 x 106/ml. If the number of cells is too high, dilute with Hank's solution, adjust the number of cells to 5 × 106 / ml, and simultaneously immerse the test tube in ice cubes for use. 4 cell sorting, using a cytospin smear device, adding 100 μl of a spare cell suspension (cell concentration of 5 × 106 cells / ml), centrifuging at 1200 r / min for 10 min at 4 ° C, a certain number of BALF cells by centrifugation Directly spread on a salt slide. The downloaded slides were immediately dried with cold air, fixed in absolute ethanol for 30 min, and stained, usually with Wright or HE staining. 5 200 cells were counted under a 40-fold optical microscope, and cell sorting was performed. (2) Detection of T lymphocyte subsets in BALF 1 Using the indirect immunofluorescence method, the BALF cell fraction obtained above was made into a cell suspension using 3 to 5 ml of 10% calf serum RPMI1640 medium. 2 Pour the cell suspension into a dish and incubate in a 5% CO237 °C incubator for 2 h for adherence to remove alveolar macrophages. 3 The cell suspension was taken out, and then centrifuged once with Hank solution, and 20 to 100 μl of the supernatant was discarded. In the cell suspension after adherent treatment, alveolar macrophages were significantly reduced, and lymphocytes were relatively increased. 4 Dispense the adherent cell suspension into 3 small conical centrifuge tubes, each tube 20 ~ 30μl, add 20 ~ 40μl of monoclonal antibodies CD3, CD4 and CD8 to the specimen with a micro-sampler, mix well Place in a refrigerator at 4 ° C for 1 to 2 hours. 5 Take out the specimen, first centrifuge with Hank liquid for 2 times, centrifuge at 12000r/min for 20s, then add 20-40μl of goat anti-mouse fluorescent antibody, and put it in the refrigerator for 30min. 6 Take the specimen and use the Hank solution to centrifuge twice at the same speed and time, discard the supernatant and leave 20 μl and mix well. Take 1 drop on the slide and cover the slide. A number of 200 lymphocytes were counted under a fluorescence microscope and the positive rate of cells marked with fluorescence was calculated. Not suitable for the crowd Cardiopulmonary dysfunction is severe, oxygen partial pressure is lower than 6.67 kPa, newly large hemoptysis, active tuberculosis without treatment. 1. All contraindications for bronchoscopy are contraindications for bronchoalveolar lavage. 2. High mental stress can not be combined with the completion of fiberoptic bronchoscopy patients. 3. Patients with severe ventilation and ventilation dysfunction, PaO2 <6.67 kPa (50 mmHg) or PaO2 <9.33 kPa (70 mmHg) under oxygen inhalation. 4. Patients with coronary heart disease, hypertension, arrhythmia, and frequent angina pectoris. 5. Aortic aneurysm and esophageal varices have a risk of rupture. 6. Patients with recent fever, hemoptysis and asthma attacks. Adverse reactions and risks There may be complications such as fever, bleeding, lung infection, and bronchospasm.