Risk factors for pneumothorax in patients with interstitial lung disease undergoing transbronchial lung cryobiopsy, a research letter

Background Pneumothorax is a common and important complication of transbronchial lung cryobiopsy (TBLC) in patients with interstitial lung disease (ILD), however little is known about what predisposes patients to pneumothorax during TBLC. Methods We reviewed the pre-TBLC ILD work-up of 76 patients who underwent TBLC in our tertiary ILD referral center from 2017 to 2023. We assessed factors including pulmonary function tests, bronchoalveolar lavage (BAL), blood tests, and imaging and to see if any of them caused an increased risk of iatrogenic pneumothorax. Results 19 patients suffered a pneumothorax (25%). Neutrophilia on BAL (37.9% pneumothorax when present vs 12.8% when not present, p = 0.046) and the presence of ground glass opacification on high resolution CT-Thorax (38.2% vs 12.5%, p = 0.014) increased the risk of pneumothorax during TBLC. Other factors such as the presence of pleura in the biopsy sample (47.1% vs 17.2%, p = 0.021), as well as taking 3 or more biopsies (35.7% vs 11.8%, p = 0.019) were also significant predictors of pneumothorax. Conclusions Markers of acute inflammation as well as increased number of biopsies taken in a procedure lead to increased risk of pneumothorax. This may lead to changes in planning, patient selection and timing of TBLC procedures in ILD patients.