Impact of gasless vNOTES vs. traditional vNOTES on hemodynamic profiles and outcomes in patients with benign gynecological disease: study protocol of a randomized controlled trial.

BACKGROUND: Literature regarding the advantages of gasless vNOTES is insufficient. The aim of our study is to compare gasless vNOTES vs. traditional vNOTES on hemodynamic profiles and outcomes in patients with benign gynecological disease. We hypothesize that compared with those in the traditional vNOTES group, hemodynamic profiles will be changed less during gasless vNOTES, while safety can be promised.

METHODS: This is a single-center, prospective, single-blind, randomized controlled clinical trial, which has been approved by the Institutional Review Board of Chengdu Women's and Children's Hospital on September 27, 2022. One hundred and twenty patients will be recruited and randomly assigned to either the traditional vNOTES group or the gasless vNOTES group in a 1:1 ratio. For patients allocated to the traditional vNOTES group, after insertion of one port through the vagina, CO2 gas is infused with a pressure of 12-14 mmHg; while for those allocated to the gasless vNOTES group, a special device is used as an abdominal wall-lifting device to facilitate gasless surgery. CO2 pneumoperitoneum will not be used during the whole gasless vNOTES procedure. The primary outcome is vital signs at different time points. The secondary outcomes include surgical conversion rate, duration of surgery and anesthesia, anesthetic consumption, intraoperative estimated blood loss, VAS and PONV scores at postoperative 2 h and 24 h, administration of vasopressor drugs from the beginning of general anesthesia induction to 15 min after endotracheal intubation, including times, dosage, and type, intraoperative and postoperative complications, time of first getting out of bed after surgery, and time of first eating after surgery, including light drink.

DISCUSSION: This is the first randomized controlled trial to compare the impacts of gasless vNOTES vs. traditional vNOTES on hemodynamic profiles and outcomes in patients with benign gynecological disease. If a favorable effect and safety of gasless vNOTES for hemodynamic profiles and outcomes in patients are shown, gasless vNOTES would be an optimal treatment option for patients with benign gynecological disease.

TRIAL REGISTRATION: The trial was registered at https://www.chictr.org.cn/showproj.html?proj=182441 with registration No. ChiCTR2200064779 on Oct 17, 2022.