Predictive risk factors for pneumothorax after transbronchial biopsy using endobronchial ultrasonography with a guide sheath

Background: Pneumothorax is one complication of transbronchial biopsy (TBB) using endobronchial ultrasonography with a guide sheath (EBUS-GS-TBB). We sought to clarify the risk factors for pneumothorax after EBUS-GS-TBB under fluoroscopic guidance. Methods: We retrospectively reviewed data from 916 patients who underwent EBUS-GS-TBB at Fujita Health University Hospital. We evaluated the following risk factors for pneumothorax after EBUS-GS-TBB: patient characteristics (sex, age, and pulmonary comorbidities); lesion data (location, size, existence of ground-glass opacities [GGOs], pleural involvement, computed tomography [CT] bronchus sign, visibility on fluoroscopy, and EBUS findings); final diagnosis; years of bronchoscopist experience; and guide sheath size. Univariate and multivariate logistic regression analyses were performed. Results: Among the 916 patients, 30 (3.28%) presented with pneumothorax. With a univariate analysis, factors that independently predisposed to pneumothorax included lesions containing GGOs, lesions in sagittal lung segments on fluoroscopy, lesions that were not visible on fluoroscopy, and infectious lesions. A univariate analysis also showed that lesions in the right upper lobe or left upper division, as well as malignant lesions, were less likely to lead to pneumothorax. Age, underlying pulmonary disease, CT bronchus sign, EBUS findings, bronchoscopist experience, and guide sheath size did not influence the incidence of pneumothorax. A multivariate analysis revealed that only lesions containing GGOs (odds ratio [OR] 6.47; 95% confidence interval [CI] 2.13–19.6, P = 0.001) and lesions in lung segments with a sagittal orientation on fluoroscopy (OR 2.47; 95% CI 1.09–5.58, P = 0.029) were significant risk factors for EBUS-GS-TBB-related pneumothorax. Conclusions: EBUS-GS-TBB of lesions containing GGOs or lesions located in sagittal lung segments on fluoroscopy correlate with a higher pneumothorax risk.