Risk factors of pneumothorax and bleeding: multivariate analysis of 660 CT-guided coaxial cutting needle lung biopsies.

BACKGROUND The results of studies identifying the risk factors for pneumothorax and bleeding in CT-guided coaxial lung needle biopsies were inconsistent and some were even contradictory. All reported series were small with patient populations averaging about 200. STUDY OBJECTIVES To determine the risk factors for pneumothorax and bleeding after CT-guided coaxial cutting needle biopsy of lung lesions. DESIGN Retrospective analysis. METHODS We reviewed 660 biopsy procedures. The risk factors for pneumothorax and bleeding were determined by multivariate analysis of variables related to patient demographics, lung lesions, biopsy procedures, and the individual radiologist. RESULTS The main complications were pneumothorax (23%; 155 of 660 procedures), chest tube insertion (1%; 9 of 660 procedures), and hemoptysis (4%; 26 of 660 procedures), with no patient mortality. The highest pneumothorax rate correlated with a lesion size of </= 2 cm, a lesion depth of 0.1 to 2 cm, and less experienced radiologists. The highest bleeding risk correlated with a lesion size </= 2 cm, a lesion depth of >/= 2.1 cm, and the absence of pleural effusion. CONCLUSIONS The risk factors for highest pneumothorax rate are lesion size </= 2 cm, a subpleural lesion depth of 0.1 to 2.0 cm, and a less experienced radiologist. The risk factors for highest bleeding rate are lesion size </= 2 cm, lesion depth >/= 2.1 cm, and lung lesions not associated with a pleural effusion.