Feasibility study of a novel rectal cooling system for hypothermic radical prostatectomy in a swine model

Thermal damage and inflammatory responses of the sphincter and neurovascular bundles (NVBs) are responsible for post-prostatectomy incontinence and erectile dysfunction. Intraoperative hypothermia in the pelvic cavity may reduce the occurrence of these complications. We evaluated the feasibility of a novel rectal cooling system using an animal model. A novel rectal cooling system consisting of a cooling console and a multi-lumen rectal balloon was developed. We conducted animal tests on male pigs to evaluate the efficacy and safety of the system. The primary endpoint was to maintain the temperature of the NVBs at 25℃ (±5℃) during and after the electrocauterization of the bladder neck for 10 seconds. The safety endpoint was device-related complications or significant changes in the core body temperature of the pigs. The NVB temperature was below 30℃ within 3 minutes of activation of the rectal balloon. The temperature of the proximal NVB was consistently maintained below 25℃ in all cases. The temperature 1 cm from the bladder neck did not rise above 38°C and dropped to the initial level within 1 minute after electrocauterization. During cooling, the minimum temperature at the apex of the prostate was reduced to 10.1℃. There were no device-related complications or significant changes in core body temperature throughout the experiment. Animal tests suggest the feasibility and safety of this novel rectal cooling system. A first-in-human trial to assess the safety and efficacy of this system during radical prostatectomy is warranted.