This study was a prospective, single-center, single-arm, pivotal clinical trial to evaluate the feasibility of cholecystectomy with the Medtronic Hugo™ RAS System. The presentation of these data represents a subset of a larger study. The other indication from the Hello Hugo pre-market investigational study was focused on urology and is currently under review to be published. The Hugo™ RAS System has received approval from the Ministry of Food and Drug Safety (MFDS) of Korea in February 2024. The full study for the MFDS is registered on ClinicalTrials.gov (http://clinicaltrials.gov; NCT05715827).

This study was conducted in compliance with the Declaration of Helsinki, Good Clinical Practice, ISO 14155:2020 requirements, the Medical Device Act, the Personal Information Protection Act, the Korea Medical Devices Industry Association Fair Trade Competition, and the site’s Institutional Review Board (IRB) requirements.

The principles of the Declaration of Helsinki were implemented through the informed consent process, IRB approval, study training, clinical trial registration, pre-clinical testing, risk–benefit assessment and publication policy. The sponsor of this trial, Medtronic, ensured to avoid improper influence on or inducement of the patients, monitors, investigators or other parties participating in or contributing to the clinical investigation.

A total of 22 cholecystectomy-indicated patients provided written consent and were enrolled consecutively in the study from February to April 2023. However, two cholecystectomy patients exited the study prior to surgery due to a surgeon decision to undergo laparoscopic surgery due to severe adhesion and inflammation for one patient and a console communication error prior to the first incision for the other. Instead, these two patients underwent a laparoscopic procedure. Thus, the remaining 20 cholecystectomy-indicated patients underwent a procedure with the Hugo™ RAS System and completed their corresponding post-procedure 30-day follow-up visit.

Inclusion criteria were patients indicated for a cholecystectomy with cholelithiasis, cholecystitis, or gallbladder polyps. Specifically, gallbladder polyps had to be ≥ 10 mm, enlarging, or symptomatic.

Exclusion criteria were: patients with a considerable risk for laparoscopic surgery (e.g., severe cardiopulmonary diseases which contraindicated to general anesthesia, uncontrolled coagulopathy, etc.), patients requiring urgent surgery, pregnant or lactating women, patients with severe liver cirrhosis (Child–Pugh class C) with portal hypertension or suspicion of gallbladder cancer, previous abdominal surgery within the past two years, concurrent participation in another clinical study, patients with a condition that could compromise study compliance (e.g., mentally incompetent, alcohol or drug abuse) as determined by the investigator, and patients who were considered unsuitable to conduct the trial as determined by the investigator.

Major complications were defined as any complication with a Clavien-Dindo Grade ≥ III. The primary study objective was a composite of a completed cholecystectomy with the Hugo™ RAS System without conversion (to open or laparoscopic surgery), and no major complications within 24 h post-procedure. The primary objective of the trial was considered achieved if the composite rate was at least 95%.

The secondary study endpoints assessed the short-term safety outcomes via the: major complication rate, overall complication rate, readmission rate, reoperation rate, and device deficiency rate all through 30 days post-procedure.

The other clinical data collected for this study subset were: baseline patient characteristics (e.g., age, height, weight, etc.), pathology characteristics, estimated blood loss, surgical setup time, total console time, operative time, and robot take-down time.

A complication in this study was defined as an unanticipated problem that arose following and was a result of, a procedure, treatment, or illness. This definition is aligned with the adverse events definition (ISO 14155:2020). Expected adverse events were not captured or reported unless the adverse event worsened or persisted. Expected adverse events included: anesthesia-related nausea/vomiting, low-grade fever (< 37.8°C), incisional pain, sleep problems (insomnia), constipation, and mild to moderate bruising/ecchymosis. The relationship of a complication to the device, underlying condition, surgical procedure, or anatomical factor was determined by the site.

The Medtronic Hugo™ RAS System is a modular robotic platform for performing robotic-assisted minimally invasive surgery. The Hugo™ RAS System has three main components: a system tower, movable individual arm carts, and an open surgeon console.

The system tower houses computers, the endoscope system, the electrosurgical generator, the power management system with a backup battery, and a high-definition interactive touchscreen display. The arm carts consist of movable platforms with casters which support an extendable robotic arm. Up to four arm carts can be connected to the system tower for simultaneous use during surgery. The arm carts are movable within the operating room (OR) and the hospital. Prior to surgery, the OR team positions the arm carts around the surgical table according to the surgical procedure. The team can adjust the arm carts and extendable arms to accommodate patient positioning and optimize bedside access to the patient. The surgeon console is an open console that consists of a flat screen with a high-definition three-dimensional (3D) display, a touchscreen interactive display, adjustable ergonomic controls, an armrest, two surgeon hand controllers, a set of foot pedals, and 3D surgeon and observer glasses. The surgeon hand controllers respond to wrist movement. Sensors in the surgeon console track the movement of the 3D glasses worn by the surgeon and can clutch the movement of the instruments if the surgeon looks away from the 3D display (Fig. 1).

The Hugo™ RAS System Overview System tower, modular arm carts, surgeon console

All patients were positioned in reverse Trendelenburg (> 20°) under general anesthesia. Incisions for ports were made according to the Medtronic Setup Guide and slightly adjusted to minimize the number of incisions. The camera port was placed through a periumbilical incision. The remaining ports were placed at a safe distance from the camera port and adjacent ports (Fig. 2A). The robotic arms were positioned according to the Medtronic Setup Guide (Fig. 2B). The endoscope and wristed instruments were attached to the robotic arms and inserted into the ports.

Surgical Setup of the Hugo™ RAS System A Port placement and B Arm cart positioning for cholecystectomy procedures

After identification of the gallbladder, the fundus was retracted cephalad over the liver with a grasping instrument. Adhesions were taken down using the Maryland dissector. An additional grasper was used to retract the gallbladder inferolaterally to expose the triangle of Calot. The separation of the cystic duct anteriorly from the cystic artery was performed with a Maryland grasper. The cystic artery was clipped and then divided by hook scissors. The dissection of the cystic pedicle was completed by placement of a clip to occlude the cystic duct. The gallbladder was separated from the liver with scissors with an electrosurgical attachment or a monopolar hook. After the gallbladder resection was complete, the gallbladder was placed in a retrieval bag and removed through the umbilical port. All incised port sites were closed.

Descriptive statistics were used to present the data and to summarize the results. Continuous variables were summarized with number of patients (n), mean, standard deviation (SD), median, and ranges. Categorical variables were summarized by frequencies and percentages.

To estimate the sample size, two things were taken into account: the number of patients from previous studies [10], and the minimum number to show whether the primary objective was met [11]. Based on these two considerations, the planned study population was 20 cholecystectomy patients.