A new endoscopic standardized grading system for macroscopic central airway complications following lung transplantion: The MDS classification

Background Anastomotic complications, after lung transplantation, include stenosis, dehiscence, granulation tissue, bronchomalacia and fistula. They have already been included in classifications. None has been universally accepted. Objective The French Bronchoscopy Group (GELF) was mandated to develop an endoscopic classification, in order to describe the macroscopic aspect of the bronchial anastomoses, and downhill airways. Methods A classification taking into account the three major items of the description of bronchial anastomoses was elaborated. The first parameter is the Macroscopic evaluation (M), the second, the Diameter (D), and the third, the Sutures (S) of the anastomosis. Each parameter can be classified from 0 to 3. It was then submitted to experts from 9 French centers responsible for lung transplant for their opinion, using of a questionnaire. Results Two rounds were necessary to allow for a consensus: the MDS classification. - M: o M0 : Scar tissue o M1 : Protruding cartilage o M2 : Inflammation/granulomas o M3 : Ischemia/Necrosis - D : o D0 : Normal to a fixed reduction o D1 : Expiratory reduction (malacia) > 50% o D2 : Fixed reduction from 33 to 66% o D3 : Fixed reduction > 66% - S : o S0 : Absence of dehiscence o S1 : Limited dehiscence ( o S2 : Extensive dehiscence (from 25 to 50%) o S3 : Very extensive dehiscence (more than 50%) NB: - For M and D: Extent of abnormalities can be graded; a, b, c, d. - For S : a : anteriorly; b : other localizations Conclusion The MDS classification could represent a standardized, universally acceptable system, to describe the central airway complications after lung transplant.