The Accuracy And Safety Of Transbronchial Cryobiopsy In Diagnosis Of Interstitial Lung Disease

Objective:To explore the accuracy and safety of Transbronchial Cryobiopsy in diagnosis of interstitial lung disease.Methods:Collect the patients with high resolution chest CT findings of interstitial lung disease admitted to our hospital from March 1,2018 to August31,2019.Inclusion criteria:for patients with high resolution CT findings of interstitial lung disease whose nature cannot be determined in combination with clinical and serological findings,Transbronchial Cryobiopsy is recommended for a definite diagnosis.Exclusion criteria:severe hypertension and arrhythmia;Myocardial infarction within 3 months or a history of unstable angina attack;Severe impairment of heart,lung,liver and kidney or extreme systemic failure;Severe pulmonary hypertension;Severe superior vena cava obstruction syndrome;Clotting disorders,anticoagulation therapy(including the use of clopidogrel or other thiophene pyridine or other new antiplatelet drugs),and severe thrombocytopenia that cannot be corrected(platelet<50×109/L);Acute exacerbation of interstitial lung disease;Patients with severe impaired lung function(FVC%<50%and D_LCO%<35%).Collect the patient's age,gender,symptoms,basic diseases,imaging manifestations,etc.Improve the patients'blood gas analysis,blood routine,blood biochemistry,coagulation function,rheumatology,hepatitis virology series,lung function,electrocardiogram and other routine examinations before surgery.Under general anesthesia,the bronchoscope(Olympus,BT-IT260,Japan)was inserted into the airway through the laryngeal mask,and a small radial ultrasound probe(UM-S20-17S,Olympus,Japan)was used to scan for dense lesions requiring biopsy,and a frozen probe(Erbokryo CA,ERBE,Germany)was used to obtain target lung tissue samples where biopsy was required by Joule Thomson effect.Observe the patient's vital signs during the operation,record the location of the material,the freezing time,the size of the tissue specimen,whether there are complications of pneumothorax and bleeding,and the operation time at the same time.Combined with the clinical,imaging and pathological data of patients,multi-disciplinary diagnosis was finally obtained.Postoperative pneumothorax and other complications should be noted.Patients were followed up to evaluate the treatment effect by telephone,outpatient,and inpatient after the operation,until the patient died or December 31,2019.Follow-up efficacy was used as the gold standard to determine the accuracy of multidisciplinary diagnosis in patients with interstitial lung disease after Transbronchial Cryobiopsy.Result:Twenty-seven eligible patients were enrolled,including 11 males and 16females,with an average age of(60.8±9.5)years.Twenty-seven patients were sampled from 1 to 3 different target lung segments,and the number of tissue specimens from each patient was 1 to 6 samples.A total of 86 samples were taken(3 times in the right upper lobe,4 times in the right middle lobe,58 times in the right lower lobe,Left lower lobe 21 times).Among the 27 patients,1 was taken from 3 target lung segments,19from 2 target lung segments,and 7 from 1 target lung segment.Two people took 4pieces of tissue from each site,four people took 3 pieces of tissue,16 people took 2pieces of tissue,and five people took 1 piece of tissue.The average operation time of Transbronchial Cryobiopsy was(11.5±4.5)minutes,the average freezing time was(3.7±0.8)seconds,the average number of tissue specimens was(3.1±1.1)blocks,and the average number of specimen sites was(1.8±0.5).The average tissue specimen size was(24.6±19.7)square millimeters.Combined with the clinical,imaging and pathological data,all 27 patients were diagnosed in a multidisciplinary manner.Regular postoperative follow-up was conducted to evaluate the efficacy.According to the results of efficacy evaluation,23 patients were able to make a clear multidisciplinary diagnosis,the known etiology was found in 5 cases(21.7%),including 3 cases(60%)of connective tissue disease associated with interstitial lung disease,1 case(20%)of common pulmonary infection,and 1 case(20%)of tumor.Idiopathic interstitial pneumonia was found in 17 cases(73.9%),including 5 cases of idiopathic pulmonary interstitial fibrosis(29.4%),cryptogenic organizing pneumonia in 4 cases(23.5%),idiopathic non-specific interstitial pneumonia combined with cryptogenic organizing pneumonia in 4 cases(23.5%),idiopathic non-specific interstitial pneumonia in 2 cases(11.8%),2cases of acute interstitial pneumonia(11.8%).No granulomatous changes(0%);Among the other types,1 case(4.4%)was alveolar proteinosis(100%).The positive diagnosis rate was 85.2%.There were 27 cases of intraoperative bleeding,including 10 cases of grade 1 bleeding and 17 cases of grade 2 bleeding.No grade 3bleeding occurred,and the bleeding stopped after corresponding measures were used to stop bleeding.A total of 3 patients had pneumothorax after operation.The incidence of pneumothorax was 11.1%,including 2 in moderate and 1 in large.All three patients with pneumothorax were absorbed after closed chest drainage.The average time of pneumothorax absorption was(4.3±4.0)days.All the 27 patients were followed up to evaluate the efficacy,among which 18 patients improved,3 patients were stable,3patients were not regularly reviewed,1 patient was cured,1 patient died of tumor,and 1patient was lost to follow-up.The sensitivity,positive predictive value and accuracy of multidisciplinary diagnosis of interstitial lung disease were 100%,85.2%and 85.2%,respectively.Conclusion:Transbronchial Cryobiopsy have a high accuracy and good safety in the diagnosis of interstitial lung disease.