Study of Transbronchial Cryobiopsy in Monitoring Complications of Lung Transplantation

Study Overview
=================
Brief Summary
-----------------
The goal of this randomized controlled trial is to compare the diagnostic efficacy and safety of transbronchial cryobiopsy (TBCB) and traditional transbronchial lung biopsy for diagnosing the lung transplantation rejection , so as to establish the evidence-based medical basis for the effectiveness and safety of TBCB for monitoring after lung transplantation, It is expected to provide a better auxiliary examination method for lung transplantation. The main questions it aims to answer are: (1) Histopathological evaluability of specimens; (2) Safety of TBCB; (3) Size and quality of specimen, and number of attempts to obtain five samples. Participants will undergo TBCB with 1.1 mm flexible cryoprobe or traditional transbronchial lung biopsy with biopsy forceps.

Official Title
-----------------
Research on Comprehensive Management of End-stage Severe Chronic Respiratory Diseases - Study of Transbronchial Cryobiopsy in Monitoring Complications of Lung Transplantation

Conditions
-----------------
Lung Transplant Rejection

Intervention / Treatment
-----------------
* Procedure: transbronchial lung cryobiopsy with a 1.1 mm flexible cryoprobe
* Procedure: transbronchial lung biopsy with biopsy forceps


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age among 18-65 years old After unilateral or bilateral lung transplantation, patient with unexplained pulmonary function decline, acute/chronic clinical lung injury or new pulmonary infiltrates or patients requiring monitoring of rejection after lung transplantation The patient should undertake routine preoperative examinations for lung cryobiopsy, including routine blood test, coagulation function, electrocardiogram, and chest CT, and the patients have no contraindications to cryobiopsy Exclusion Criteria: patients intolerable to undertake lung biopsy due to severe cardiopulmonary insufficiency or being weak The patient is allergic to lidocaine and midazolam The patient has recent active massive hemoptysis, or the proposed biopsy site has a high risk of bleeding, such as bronchial artery penetration or suspected renal cancer lung metastasis Unstable angina, congestive heart failure, severe bronchial asthma or multiple bullae Severe hypertension and arrhythmia, hemodynamic instability and severe respiratory failure (PaO2<60mmHg after oxygen therapy or mechanical ventilation) The patient has coagulation disorder and unable to stop taking anticoagulants, antiplatelet drugs, aspirin or non-steroidal anti-inflammatory drugs before lung biopsy Suspected aortic aneurysm The patient does not agree to participate in this study Participating in other studies within three months and not withdrawing or ending The researchers think that the patient are not suitable for inclusion

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: transbronchial cryobiopsy<br>transbronchial cryobiopsy with a 1.1 mm flexible cryoprobe | Procedure: transbronchial lung cryobiopsy with a 1.1 mm flexible cryoprobe<br>* Obtaining lung biopsy samples of patients after lung transplantation through transbronchial lung cryobiopsy with a 1.1 mm flexible cryoprobe<br>|
| Active Comparator: transbronchial lung biopsy<br>transbronchial lung biopsy with biopsy forceps | Procedure: transbronchial lung biopsy with biopsy forceps<br>* Obtaining lung biopsy samples of patients after lung transplantation through transbronchial lung biopsy with biopsy forceps<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic efficacy of transbronchial cryobiopsy versus traditional transbronchial lung biopsy for diagnosing the lung transplantation rejection | Diagnostic yield of transbronchial cryobiopsy (TBCB) for diagnosing the lung transplantation rejection, compare with that of traditional transbronchial lung biopsy. The reference standard is the result of Multi-Disciplinary Treatment (MDT). | 7 days after lung biopsy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of complications | Incidence of complications | one day, 3 days and 7 days after lung biopsy | 
| Sample size | The area size of the biopsy sample will be measured using the software Image J (version 1.48; Maryland, MD, USA) , and measured in square millimetres. | during surgery | 
| the number of alveoli in the biopsy sample | The number of alveoli in the biopsy sample is recorded, according to the histological analysis of the biopsy paraffin section. | 7 days after lung biopsy | 
| the number of blood vessels in the biopsy sample | The number of blood vessels in the biopsy sample is recorded, according to the histological analysis of the biopsy paraffin section. | 7 days after lung biopsy | 
| the percentage of the area of lung parenchyma without artifacts in the biopsy sample | The percentage of the area of lung parenchyma without artifacts in the biopsy sample is measured (by the software Image J) and recorded, according to the histological analysis of the biopsy paraffin section. | 7 days after lung biopsy | 
| number of attempts to get five samples | number of attempts to get five samples | during surgery |