BackgroundHigh-energy devices allow better vessel sealing compared with monopolar electrocautery and could improve the outcomes of surgical operations. The objective of the study was to compare tissue dissection by the LigaSure™ device with that by monopolar electrocoagulation for thoracoscopic lobectomy and lymphadenectomy.MethodsThis pragmatic, parallel group, prospective randomized controlled trial was funded by the Medtronic External Research Program (ISR-2016–10,756) and registered atwww.clinicaltrials.gov(NCT03125798). The study included patients aged 18 years or older, who had undergone thoracoscopic lobectomy with lymphadenectomy at the Department of Thoracic Surgery of Poznan University of Medical Sciences between May 3, 2018, and November 4, 2021. Using simple randomization, the patients were assigned to undergo tissue dissection with either the LigaSure device (study group) or monopolar electrocautery (control group). Participants and care givers, except operating surgeons, were blinded to group assignment. The primary outcome was postoperative chest drainage volume. Secondary outcomes were change of the esophageal temperature during subcarinal lymphadenectomy and C-reactive protein level 72 h after surgery.ResultsStudy outcomes were analyzed in 107 patients in each group. We found no differences between the study and control groups in terms of chest drainage volume (550 vs. 600 mL, respectively;p= 0.315), changes in esophageal temperature (− 0.1 °C vs. − 0.1 °C, respectively;p= 0.784), and C-reactive protein levels (72.8 vs. 70.8 mg/L, respectively;p= 0.503). The mean numbers of lymph nodes removed were 12.9 (SD: 3.1; 95% CI, 12.4 to 13.5) in the study group and 11.6 (SD: 3.2; 95% CI, 11.0 to 12.2) in the control group (p< 0.001).ConclusionsThe use of the LigaSure device did not allow to decrease the chest drainage volume, local thermal spread, and systemic inflammatory response. The number of lymph nodes removed was higher in patients operated with the LigaSure device, which indicated better quality of lymphadenectomy.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00464-023-09892-0.