Safety and diagnostic yield of transbronchial lung cryobiopsy in patients with interstitial lung disease and severe pulmonary function impairment

Abstract Background Transbronchial lung cryobiopsy (TBLC) has become an established diagnostic modality in interstitial lung disease (ILD). However, current guidelines frequently exclude patients with severely impaired lung function due to safety concerns. This study aimed to evaluate the safety and diagnostic yield of TBLC in patients with advanced pulmonary function impairment. Methods We conducted a retrospective analysis of consecutive patients with suspected ILD who underwent TBLC for diagnostic evaluation at Thoraxklinik Heidelberg, University Hospital Heidelberg, between November 2017 and December 2021. All cases were reviewed in a multidisciplinary discussion (MDD) before and after biopsy. Severe pulmonary function impairment was defined as a forced vital capacity (FVC) < 50% predicted and/or a diffusing capacity for carbon monoxide (DLCO SB ) < 35% predicted. Procedural complications and diagnostic yield were assessed following post-procedural MDD. Results A total of 396 patients were included (39% female, mean age 68 ± 12 years), of whom 43 patients (10.9%) had severely physiologically impaired ILD (SPI-ILD). The incidence of pneumothorax did not statistically differ between patients with severe and less physiologically impaired ILD (LPI-ILD) (11.6% vs. 14.7%, p = 0.818), with chest tube placement required in 33 cases overall. Severe bleeding necessitating endoscopic haemostasis occurred in 25.6% of SPI-ILD and 17.8% of LPI-ILD patients ( p = 0.218). No surgical interventions for procedure-related complications were required. TBLC contributed to a final diagnosis following MDD review in 318 patients (80%), including 81% in SPI-ILD and 80% in LPI-ILD ( p = 1.000). Conclusion TBLC may represent a viable diagnostic option in carefully selected patients with severely impaired pulmonary function when performed in experienced centres following thorough risk–benefit assessment.