Objective:Based on experience of robotic gastrointestinal surgery at the Department of General Surgery, Clinical Medicine Center of Gansu Provincial Hospital, this study explored the principles and methods of trocar layout for robotic "3+2" mode gastrointestinal surgery, suitable for beginners.Methods:From Apr 2017 to Oct 2022, the robotic gastrointestinal surgery team of Gansu Provincial Hospital completed 998 cases of robotic "3+2" mode gastrointestinal surgery, including 600 cases of gastric cancer, 100 cases of rectal cancer, 98 cases of descending colon and sigmoid colon cancer, 20 cases of transverse colon cancer, and 180 cases of right colon cancer. Through the continuous optimization and improvement of the problems encountered during the operation, combined with the operator's experience, and taking into account various aspects, we developed the robotic "3+2" mode trocar layout for gastrointestinal surgery.Results:Four principles of trocar layout were developed, namely, the principle of lens placement around the navel, the principle of symmetry in the main operation, the principle of 8-10cm distance between trocar holes, and the principle of symmetry in the auxiliary hole lens. Three trocar layout methods and principles applicable to robotic gastric surgery, and four applicable to robotic colorectal surgery were developed.Conclusion:The trocar layout method of robotic "3+2" mode gastrointestinal surgery is established based on a large number of robotic gastrointestinal surgery experiences. This method is simple and easy to learn, with strong repeatability and operability.

Objective To investigate the feasibility of robotic-assisted"3+1"surgical mode strategy for the treatment of median arcuate ligament syndrome(MALS).Methods Six patients diagnosed as MALS were enrolled between June 2019 and October 2023.The utilization of robotic-assisted"3+1"surgical mode(a 4-hole operation with 3 robot arms and 1 assistance hole)was carried out.Through a posterior splenic artery approach,the compression of the midline arcuate ligament on the abdominal trunk was relieved,which was an abdominal trunk vascularization.Results All the 6 patients underwent robotic-assisted"3+1"surgical mode successfully.The surgical duration(including the time for connecting and disconnecting the machine)was 38-52 min,with a mean of 43.2 min.The intraoperative bleeding volume was 5-25 ml,with a mean of 15 ml.The postoperative hospital stay was 6-9 d,with a mean of 7.5 d.All the 6 patients were followed up for 1-45 months after surgery(median,2.5 months).One patient remained unchanged in body weight,while 5 patients gained 1.0-2.0 kg in body weight,with a mean of 1.5 kg.The symptom of postprandial epigastric pain completely resolved in 5 patients,while the symptom was reduced but not completely alleviated in one patient.Conclusion Treatment of MALS with the robotic-assisted"3+1"surgical model involving abdominal trunk vascularization through a posterior splenic artery approach is safe and feasible.