Abstract
BACKGROUND: Central vascular stump oozing after pulmonary vessel stapling remains a clinically relevant challenge in thoracic surgery. Powered staplers are standard, but the optimal firing speed for minimizing bleeding has not been established. We evaluated whether the slow-firing mode reduces intraoperative stump oozing compared with the default fast-firing mode. METHODS: This retrospective two-center cohort study analyzed 276 pulmonary vessel stapling events (168 slow-firing and 108 fast-firing) during anatomic pulmonary resections performed with a powered stapler (Signia™, Medtronic) that allows manual adjustment of firing speed. The primary outcome was stump oozing lasting ≥15 seconds after vascular transection. Secondary outcomes included the need for hemostatic intervention and stapling time. Inverse probability of treatment weighting (IPTW) and multivariable logistic regression were applied to adjust for baseline and intraoperative confounders, including vessel type, vessel diameter, and intraoperative mechanical stress (lifting, twisting, and traction). RESULTS: Stump oozing occurred in 23.2% of stapling events. The incidence was significantly lower in the slow-firing group than in the fast-firing group (17.9% vs. 31.5%; P=0.01). After IPTW adjustment, slow-firing mode remained independently associated with a reduced risk of stump oozing (odds ratio, 0.51; 95% confidence interval: 0.28-0.93; P=0.03). Multivariable analysis further identified pulmonary artery (PA) stapling, lifting, and traction as independent risk factors. CONCLUSIONS: Slow-firing mode significantly reduced the incidence of prolonged stump oozing from central vascular stumps, particularly during PA transection. These findings suggest that selective use of slow-firing mode may represent a simple and practical strategy to improve staple-line security, although confirmation in larger prospective studies is warranted.