A Comparison of Robot-assisted Single Site and Laparoscopic Single-incision Cholecystectomy for Benign Gallbladder

A single-blinded randomized clinical trial (RCT) designed to compare Single-Site robot-assisted with single-incision laparoscopic cholecystectomy. The study directly compares both surgical approaches in a cohort of 60 patients (30 patients in each arm) with benign gallbladder disease from the Department of Surgery at the Cantonal Hospital of Winterthur (Kantonsspital Winterthur) in Switzerland. The primary endpoint of the study is the surgeon's physical and mental stress load at the time of surgery and is assessed by validated Local Experienced Discomfort (LED) and Subjective Mental Effort Questionnaire (SMEQ) visual analogue scales. The secondary endpoints include costs of the procedure, intra-operative blood loss, operating time, intra-operative conversion rate and additional trocar placement, complications, length of hospital stay, Health-Related Quality of Life (HRQoL) and cosmesis. HRQoL and cosmesis will be assessed using the validated Gastrointestinal Quality of Life Index (GIQLI) and the Body Image Questionnaires (BIQ), respectively. The inclusion criteria cover most notably symptomatic cholecystolithiasis, chronic cholecystitis, benign gallbladder polyps and age ≥18 years. The exclusion criteria are, among others, acute cholecystitis, emergency cholecystectomy, previous extensive upper abdominal surgery and suspicion of malignant disease. Non-stratified block randomization (random block sizes 2 and 4) will be used to achieve balance in the allocation of participants to both treatments arms and prevent a premature decoding of the randomization scheme. Hereby, the patient will not be informed about the group assignment until the last outpatient follow-up and only after he/she has completed and returned all required questionnaires (GIQLI and BIQ). The operation will be performed according to the group assignment by senior surgeons only who have a wide experience in both robotic Single-Site and conventional single-incision laparoscopy. All data are recorded safely using the SecuTrialTM program. Sample-size calculations are based on the results of the previously mentioned experimental setup by Schatte et al, utilizing an estimated effect size of 0.8, at a power of 0.8 and an alpha-error level of 0.05, as well as considering a potential additional error margin of 10-15% of the calculations (G-Power 3.1 software, Heinrich-Heine University Duesseldorf/Germany). The estimated total duration of the study is 1.5 years, including the scheduled 1-month and 1-year postoperative follow-up visits. The study will be carried out in accordance with principles enunciated in the current version of the Declaration of Helsinki, the guidelines of Good Clinical Practice (GCP) issued by International Conference on Harmonization (ICH), and Swiss regulatory authority's requirements.