Pneumothorax After Transbronchial Biopsy in Pulmonary Fibrosis: Lessons from the Multicenter COMET Trial

Some patients with diffuse interstitial lung disease (ILD) undergo bronchoscopy with transbronchial biopsy (TBB) as part of their diagnostic evaluation. It is unclear what the incidence and risk factors for pneumothorax (PTX) following TBB are in this patient population.

Ninety-seven subjects with pulmonary fibrosis who underwent a research bronchoscopy with TBB as part of the multicenter correlating outcomes with biochemical markers to estimate time-progression in idiopathic pulmonary fibrosis (COMET) trial were retrospectively reviewed. We compared subjects who developed a PTX during research bronchoscopy with TBB versus those who did not.

Seven patients (7.2%) experienced a PTX during research bronchoscopy with TBB. Subjects who experienced PTX during TBB had significantly lower DL_CO percent predicted (29 ± 8 vs. 45 ± 15, P = 0.006) and had lower resting room air saturation of peripheral oxygen (SPO₂) on 6-min walk testing (91 ± 10 vs. 95 ± 3, P = 0.02). No differences between groups were found with respect to age, gender, race, BMI, HRCT characteristics, or the number of transbronchial biopsies performed.

The incidence of PTX following research bronchoscopy with TBB in patients with pulmonary fibrosis was found to be 7.2% in this study. Patients who developed a pneumothorax had greater impairments in gas exchange at baseline evidenced by a lower DL_CO  % predicted and a lower resting room air SPO₂ compared with subjects without PTX as a complication.