Abnormal Pulmonary Function Testing as an Independent Risk Factor for Procedural Complications During Transthoracic Needle Biopsies

Background: Computed tomography (CT)-guided transthoracic needle biopsy is an important diagnostic tool for pulmonary nodules, offering a less invasive alternative to surgical procedures. This study aims to better risk stratify patients undergoing this procedure by analyzing the pulmonary function testing (PFT), imaging characteristics, and patient demographics most associated with complications. Patients and Methods: This retrospective study involved 254 patients undergoing transthoracic needle biopsies at 3 hospitals between October 2016 and December 2019. Demographic data, extent of emphysema, and target lesion characteristics were recorded. Complications were defined as minor (small pneumothorax, mild hemoptysis, or pulmonary hemorrhage) and major (pneumothorax requiring chest tube, hemothorax, rapid atrial fibrillation, or postprocedure hypotension or hypoxia). Results: There were 50 minor (20%) and 18 major complications (7%). As seen with prior studies, older age, increased distance to pleura, and smaller nodule size correlated with an increased risk of complications. Uniquely to our study, emphysema severity, seen on CT (P=0.008) and with decreased forced expiratory volume/forced vital capacity ratio, conferred an increased risk (62.94 vs. 68.74, P=0.05) of complications. Decreased Hounsfield unit of surrounding lung (a surrogate measure of emphysema) and decreased diffusion capacity (11.81 vs. 14.93, P=0.05) were associated with increased risk of major complications. Interestingly, body mass index and comorbidities had no correlation with complications. Conclusion: In addition to previous well-described characteristics, we described physiological data (abnormal PFTs), imaging findings, and nodule location as risk factors of procedural complications. Obtaining preprocedural PFT, in addition to reviewing CT imaging and demographic data, may aid clinicians in better risk stratifying patients undergoing transthoracic needle biopsies.