Does Ipsilateral-Dependent Positioning During Percutaneous Lung Biopsy Decrease the Risk of Pneumothorax?

OBJECTIVE. The purpose of this study is to determine whether placing patients in an ipsilateral-dependent position during percutaneous CT-guided transthoracic biopsy reduces the pneumothorax rate. MATERIALS AND METHODS. Between July 2013 and August 2017, a total of 516 patients (317 men and 199 women; mean age, 66.4 years) underwent core needle biopsies performed using 17- and 18-gauge needles. The overall pneumothorax rate and the rate of pneumothorax requiring drainage catheter insertion were compared between group A (patients placed in an ipsilateral-dependent position) and group B (patients placed in a position other than the ipsilateral-dependent position), with use of a chi-square test or Fisher exact test, as appropriate. Linear regression analysis and multiple regression analysis were performed for risk factors of pneumothorax, including patient characteristics (e.g., emphysema along the needle track), lesion characteristics (e.g., size and position), and biopsy technique characteristics (e.g., needle path length, needle-pleura angle, and fissure crossing). RESULTS. For patients in group A and group B, the overall pneumothorax rate (21/94 [22.3%] and 95/422 [22.5%], respectively; p = 0.97) and the rate of pneumothorax requiring drainage catheter insertion (6/94 [6.4%] and 28/422 [6.6%], respectively; p = 0.90) were not statistically different. After multiple regression analysis, the only independent risk factors for pneumothorax and insertion of a drainage catheter were needle path length (p < 0.001 and p = 0.02, respectively), emphysema along the needle track (p = 0.01 and p < 0.001, respectively), and fissure crossing p = 0.04 and p < 0.001, respectively). CONCLUSION. Even though the pneumothorax rate does not appear to be reduced, with the limits of a retrospective evaluation considered, other advantages of the ipsilateral decubitus position exist, including protection of the contralateral lung in patients with severe hemoptysis.