Predictors of pneumothorax after transbronchial lung cryobiopsy for diagnosis of interstitial lung diseases

Abstract

<b>Introduction:</b> Transbronchial lung cryobiopsy (TBLC) has been used in the diagnostic workup of interstitial lung diseases (ILD), due to its high diagnostic yield and relatively low morbimortality. Still, TBLC is not innocuous, and the high rate of pneumothorax (PTX) has been a major concern. The aim of this study was to identify predictors of post-TBLC PTX. <b>Methods:</b> We retrospectively analyzed patients who underwent TBLC for ILD diagnosis. Clinical data and TBLC performance were reviewed. A multivariate logistic regression model was built to determine independent predictors of post-TBLC PTX. <b>Results:</b> Among 249 patients (60.6% male, mean age 61.5±12.2 years), 52 (20.9%) had post-TBLC PTX and 39 (15.7%) required drainage. Patients presenting PTX had significantly higher FEV1/FVC ratio, lower TLC and lower DLCO. There was an association between PTX and radiological UIP pattern, histological UIP pattern, number of lobes biopsied, &gt;4 biopsies performed and pleura representation in samples. Concerning PTX needing drainage, we found a statistically significant association with radiological UIP pattern, pleura representation in samples, &gt;4 biopsies performed and diagnosis of smoking related lung disease. Independent predictors of post-TBLC PTX were the radiological UIP pattern (p=0.011), high FEV1/FVC ratio (p=0.02) and pleural representation on histology (p=0.004). <b>Conclusion:</b> In our series, PTX was a common complication after TBLC, although only 15.7% required drainage. We identified several risk factors that increase the PTX rate, of which radiological UIP pattern, high FEV1/FVC ratio and presence of pleura in samples presented the highest impact to predict PTX.