Transbronchial lung cryobiopsy (TBLC) for diagnosing interstitial lung disease and peripheral pulmonary lesions is a high-yield diagnostic and safe procedure. We describe a stepwise approach to conduct TBLC for the different indications mentioned with a flexible bronchoscope, which might be helpful for novice bronchoscopists performing TBLC.
Transbronchial lung cryobiopsy (TBLC) is an invasive procedure increasingly implemented during the last decade as an alternative to video-assisted thoracic surgery lung biopsy (SLB) for diagnosing interstitial lung diseases (ILDs). The indication for TBLC has primarily been to sub-classify a specific ILD subtype when this cannot be achieved on the basis of a preceding multidisciplinary team discussion. Although SLB is considered the gold standard for establishing a histological diagnosis, TBLC has been gradually suggested as the first-choice histological diagnostic modality in patients with unclassified ILDs due to a comparable diagnostic yield with SLB, but superior to SLB in terms of complications, including mortality. During recent years, radial endobronchial ultrasound (R-EBUS) and electromagnetic navigation bronchoscopy (ENB)-guided TBLC for peripheral pulmonary lesions have also been described as safe procedures, which may improve the diagnostic yield compared to forceps biopsies. Still, the diagnostic properties of TBLC rely on the quality of the procedure's performance. This article aims to describe the stepwise approach to conducting TBLC with a flexible bronchoscope for the different indications mentioned, which might be helpful for novice bronchoscopists performing TBLC.
Interstitial lung diseases (ILDs) constitute a group of both acute and chronic lung diseases that affect one or more of all the lung parenchymal components forming the interstitium such as bronchi, alveoli, connective tissue, and blood- and lymphatic vessels. Despite being rare diseases, the more than 200 different subtypes of ILDs represent a heterogeneous disease category with different clinical, radiological, and cyto-histological characteristics. ILDs typically manifest as inflammation, fibrosis, or a combination of both, which are the underlying causes for the patients' usual perceived symptoms as dry cough, dyspnea on exertion, and fatigue1,2.
ILDs are categorized as idiopathic interstitial pneumonia (IIP), interstitial pneumonia of known etiology (e.g., connective tissue disease interstitial lung disease, drug-induced ILD, and work-related pneumoconiosis), granulomatous interstitial affection (e.g., sarcoidosis and hypersensitivity pneumonia), and orphan ILDs (e.g., multiple cystic lung diseases and eosinophilic pneumonia)1. This categorization and further diagnostic subtyping are fundamental to determining optimal treatment and follow-up, and allow prognostication. However, as the diagnostic puzzle may be challenging, interpretation of available clinical (including anamnesis, disposition, and potential exposures) and paraclinical information as chest high-resolution computed tomography (HRCT), lung physiology, and autoimmunology obtained on the basis of a multidisciplinary team discussion (MDD) is recommended3,4,5. If a confident MDD diagnosis is not obtainable6,7, histological sampling to increase the likelihood of a definite ILD subtype diagnosis is indicated by the use of transbronchial lung cryobiopsy (TBLC)8,9. In well-selected patients, TBLC is considered a safe invasive procedure with a diagnostic accuracy close to that of video-assisted thoracic surgery lung biopsy (SLB), which is still regarded as the histological gold standard for histological ILD diagnostics10,11,12,13,14. The TBLC procedure is performed as a systematic bronchoscopy, applying special cryoprobes for histological sampling and with recommended fluoroscopic guidance. It is recommended that TBLC is performed in tertiary ILD centers using an MDD setting and by interventional pulmonologists familiar with the management of TBLC complications, who have undergone training in a dedicated center with TBLC expertise9,10,11,15,16,17.
TBLC has also recently gained attention as a procedure to be combined with radial endobronchial ultrasound (R-EBUS) for ILD diagnostics18,19. Furthermore, TBLC has been combined with both R-EBUS and electromagnetic navigation bronchoscopy (ENB) for diagnosing peripheral pulmonary lesions (PPL) to improve the diagnostic yield when compared to conventional transbronchial forceps biopsies20,21. However, this relatively novel approach for PPL diagnostics has not yet been implemented as a standard procedure and thus, warrants further evidence in this specific area. The aim of the present report is to describe a stepwise approach to conducting TBLC with a flexible bronchoscope in a clinical setting for the indications mentioned.
Regardless of the indication for TBLC, its diagnostic properties rely on the quality of the procedure's performance and the selected criteria for undergoing the procedure. This emphasizes the recommendation of implementing a formal and certified training program to acquire the competences required to perform a standardized TBLC procedure. Despite the fact that no official TBLC education is currently obtainable, the recent European Respiratory Society guideline on TBLC for ILD suggests that interventional pulmonologis…
The authors have nothing to disclose.
The authors would like to acknowledge the personnel from the Departments of Thoracic Surgery and Anesthesiology at the Bronchoscopy Ward at Odense University Hospital, Denmark, for their help with the preparation of the figures for this article.
"Chimney" for tube | |||
CO2 gas bottle adapter | |||
CO2 gas tank | Erbe | ||
Endoscopy column | |||
Endotracheal tube, size 7.5-8.5 mm | Erbe | ||
Erbecryo pedal footswitch | Erbe | ||
Erbecryo2 workstation | Erbe | ||
Flexible bronchoscope | |||
Flexible gas hose | Mediland | ||
Flexible single use cryoprobe, OD 1.1 mm | Erbe | ||
Flexible single use cryoprobe, OD 1.7 mm | Erbe | ||
Flexible single use cryoprobe, OD 2.4 mm | |||
Fluoroscope | |||
Fogarty balloon catheter | |||
Formalin glasses in closed system | |||
NaCl incl. cold NaCl | |||
Pean for fixating Fogarty balloon | |||
Sterile disposable cup | |||
Sterile suction tube | |||
Sterile tweesers | |||
Syringe for Fogarty balloon inflation/deflation | |||
Table bag for flouroscope | |||
Three way tap for Fogarty balloon syringe | |||
Tracheal suction | |||
Ultrasound machine | Erbe | ||
Valve for biopsy chanel | |||
Valve to suction duct |
.