Staple Formation by Endostapler and Bronchial Wall Thickness in Pulmonary Lobectomy: A Prospective Observational Study

INTRODUCTION: To evaluate staple formation according to endostapler cartridge type and bronchial wall thickness in patients undergoing pulmonary lobectomy. METHODS: We prospectively enrolled patients scheduled to undergo lower lobectomy. The bronchus was divided by using an endostapler (ECHELON FLEX Powered Plus Stapler). The cartridge (gold, green, or black) was selected at the surgeon's discretion. After measuring the bronchial stump thickness, the bronchial tissue was proteolyzed, and all staple formations were scored from 1 to 3 points, with 3 representing an approximately perfect B-shaped staple. RESULTS: Eighty patients were enrolled. Gold, green, and black cartridges were used in 26, 49, and five patients, respectively. Green/black cartridges were used more frequently in patients with thicker bronchial stumps (p = 0.001) than gold. The mean staple formation score tended to be higher for green/black than gold cartridges (p = 0.087). The proportion of scores ≥ 2 was equivalent (p = 0.766). The proportion of score 3 was higher for green/black than gold cartridges (p < 0.001). Bronchial stump thickness significantly correlated with sex (p < 0.001) and height (p = 0.001). For men and women > 160 cm in height, the mean score tended to be higher for green/black than gold cartridges (p = 0.068). No postoperative bronchopleural fistulae were observed. CONCLUSIONS: Although each cartridge performed well, ensuring tissue apposition and good clinical outcomes, green or black cartridges appeared to be more appropriate than gold for the lower bronchus, especially in men and women > 160 cm in height. TRIAL REGISTRATION: UMIN000043969.