The factor analysis of the incidence of pneumothorax after CT-guided transthoracic needle aspiration biopsy

Objective: To analyze the impact of multiple factors on the incidence of pneumothorax associated with CT-guided transthoracic needle aspiration biopsy. Methods: The sign of pneumothorax after 162 cases (lesion diameter from 1 cm to 6 cm) CT-guided transthoracic needle aspiration biopsy was observed and its relationship with multivariate factors were analyzed by multivariate logistic regression model. Results: Thirty-two cases presented pneumothorax accounting for 19. 8%. Single variate analysis showed that the sign of pneumothorax related to intercurrent COPD, distance from lesion and chest wall, needle dwelling time and lesion diameter. 67 patients of intercurrent COPD with postoperative pneumothorax occurred in 22 cases (32.8%); With respect to those having lesions close to the chest wall (48 cases), and the cases with the distance between the chest wall and lesions less than 2 cm (55 cases) and greater than 2 cm (59 cases), the postoperative pneumothorax occurred in 0, 14 (25.5%), 18 (30.5%) cases respectively; For those patients with needle in the chest residence time of less than 10 minutes (82 cases), 10-20 minutes (51 cases), more than 20 minutes (28 cases) after the occurrence of pneumothorax were 8 (9.6%), 10(19.6%), 14 (50%) cases respectively; In contrast, those with lesion diameter less than 2 cm (65 cases), 2-4 cm(52 cases), more than 4cm(45 cases) were 19 (29.2%), 8 (15.4%) and 5 (11.1% ) respectively. The multivariate logistic regression analysis showed that the prior three factor's were risk factors of pneumothorax (OR=4.652, 4.030, 2.855 respectively). Conclusions: To avoid the pneumothorax, caution must be taken with respect to CT-guided transthoracic needle aspiration biopsy, patients with intercurrent COPD, long distance between lesion and chest wall, and smaller lesion diameter. For operation the needle dwell time within thorax should be minimized. (authors)