PROtective ventilation with FLOW-controlled ventilation in ROBOT-assisted laparoscopic surgery (PROFLOW-ROBOTic pilot) -- study protocol for an international multicenter pilot randomized clinical trial.

Abstract

Background: Optimizing intraoperative ventilation is crucial during robot-assisted laparoscopic surgery, where pneumoperitoneum and extreme body positioning impact respiratory system compliance and gas exchange. Flow-controlled ventilation (FCV) regulates both inspiratory and expiratory gas flow, and has shown benefits in both animal and human studies. However, its safe application and feasibility during robot-assisted laparoscopic surgery and its impact on reducing postoperative pulmonary complications (PPC) remain unclear.

Aim: To test the safety and feasibility of a study protocol for a future randomized clinical trial of FCV with compliance-guided titration of positive end-expiratory pressure (PEEP) and driving pressure (ΔP) in patients scheduled for robot-assisted laparoscopic surgery.

Methods: This pilot study assesses the safety and feasibility of a study protocol that includes a ventilation bundle consisting of FCV with dynamic compliance-guided titration of PEEP and ΔP. The control group will receive conventional pressure-controlled ventilation with PEEP set at 5-10 cmH₂O and a tidal volume of 7-9 ml/kg predicted bodyweight, in line with current best practices at the participating centres. The primary outcome focuses on the safety of using FCV, including gas exchange metrics, ventilator settings, ventilation parameters, and the incidence of intraoperative respiratory and haemodynamic complications. Secondary outcomes focus on the feasibility of FCV with individualized PEEP and driving pressure, the suitability of the study protocol, and safety endpoints such as the incidence of PPC during the first 7 postoperative days.

Discussion: PROFLOW-ROBOTic will be the first international, multicentre study to investigate a protocol consisting of a ventilation bundle that includes FCV with dynamic compliance-guided titration of PEEP and ΔP and its effect on the incidence of PPC in patients undergoing robot-assisted laparoscopic surgery. This pilot study analyses the safety and feasibility of the FCV with individualized PEEP and ΔP ventilation protocol, and will inform the design of the future PROFLOW-ROBOTic trial that will test the efficacy of FCV with compliance-guided titration of PEEP and ΔP versus standard pressure-controlled ventilation (PCV) with respect to PPC in these patients.