Risk factors for PPCs in laparoscopic non-robotic vs laparoscopic robotic abdominal surgery (LapRas): Rationale and protocol for a patient-level analysis of LAS VEGAS and AVATaR

Introduction: Postoperative pulmonary complications (PPC) vary in different surgical techniques. We aim to compare the incidence of PPCs after laparoscopic non-robotic versus laparoscopic robotic abdominal surgery. Methods and analysis: LapRas (Risk Factors for PPCs in Laparoscopic Non-Robotic vs Laparoscopic Robotic Abdominal Surgery) analyses harmonized data from two observational studies on abdominal surgery patients and PPCs: Local ASsessment of VEntilatory management during General Anaesthesia for Surgery (LAS VEGAS), and Assessment of Ventilation during general AnesThesia for Robotic surgery (AVATaR). The primary endpoint is the occurrence of one or more PPC within the first five postoperative days. Secondary endpoints include the occurrence of each individual PPC, hospital length of stay, and in-hospital mortality. Logistic regression models will be used to identify risk factors for PPCs in laparoscopic non-robotic versus laparoscopic robotic abdominal surgery. We will investigate whether differences in the occurrence of PPCs between the groups are driven by differences in duration of anaesthesia and/or the intensity of mechanical ventilation. Ethics and dissemination: This analysis will address a clinically relevant research question by comparing laparoscopic and robotic surgery. No additional ethical committee approval is required for this meta-analysis. Data will be shared with the scientific community in the form of abstracts and original articles submitted to peer-reviewed journals. Registration: The registration of this post-hoc analysis is pending; individual studies that were merged into the study database were registered at clinicaltrials.gov: LAS VEGAS with identifier NCT01601223, AVATaR with identifier NCT02989415.