Background: The National Health System is responsible for 8–10% of total greenhouse gas emissions. Operating rooms are responsible for 60–70% of all hospital waste. Over the last 30 years abdominal surgery transcended from a laparoscopic approach toward a robot-assisted approach. The role of robot-assisted laparoscopic surgery is still debated in some procedures, such as colorectal surgery. The studies available in scientific literature comparing laparoscopic and robot-assisted left hemicolectomy are focused on clinical outcomes. The environmental sustainability of these procedures remains largely unexplored, representing a key area that our study seeks to investigate. Methods: In this pilot study consecutive patients scheduled for a minimally invasive left hemicolectomy for diverticular disease or cancer were recruited and randomly assigned 1:1 to the laparoscopic or robotic groups. The “Green Team” supported the operating room staff in separate waste collection during the surgical procedures. Primary end point was CO₂ consumption and secondary endpoints the specific mass of the most important waste stream. Results: Ten patients were enrolled. Robot-assisted left hemicolectomy required more CO₂ consumption in liters to maintain pneumoperitoneum (p = 0.03) compared with laparoscopic left hemicolectomy and required a longer operation time (p = 0.04). In total, the robot and laparoscopic approaches produced a total of 74.5 and 54 kg of plastic, non-woven fabric (TNT), unsorted waste bins, and biohazardous waste combined, which cost €92 and €71 to dispose of. Conclusion: Robot-assisted left hemicolectomy seems to have a greater environmental impact compared with laparoscopic left hemicolectomy in terms of both CO₂ emissions and waste production. Given the growing focus on operating room sustainability, further studies are needed to compare laparoscopic and robotic techniques to inform surgical decisions.

Hospitals in Europe produce approximately 6 million tons of medical waste annually, about one-third of this originating in operating rooms. Most of it is solid waste, which can be recycled if bodily fluids do not contaminate it. Only 2–3% of hospital waste must be disposed of as infectious waste, and this is much lower than the 50–70% of garbage in the biohazard waste stream. In June 2021, at the main operating room of the Department of General Surgery of the University of Turin, we began a separate collection program for materials consisting of plastic, paper, TNT (material not contaminated by bodily fluids), and biohazardous waste. We calculated the number of boxes and the weight of special waste disposed produced every month in one operating room for 18 months. The monthly number of Sanibox and the monthly weight of biohazardous waste decreased during the observation period. The reduction trend was not constant but showed variations during the 18 months. Direct proportionality between number of low-complexity procedures and production of biohazardous waste was found (p = 0.050). We observed an optimization in the collection and filling of plastic, paper and TNT boxes separated and sent for recycling. One of the barriers to recycling hospital waste, and surgical waste in particular, is the failure to separate infectious waste from clean waste. A careful separate collection of waste in the operating room is the first step in reducing environmental pollution and management costs for the disposal of hospital waste.