LAUSR

for patients with lower urinary tract symptoms (LUTS) remains the most effective means to provide symptomatic improvement. Many studies have evaluated the bleeding complication profile post-operatively for TURP and report a range up to 7% of patients requiring a blood transfusion, but with typical limitations in treating prostates up to 80mL in size. For larger prostates (>80mL), open prostatectomy and Holmium laser enucleation of the prostate (HOLEP) are the global reference standard surgical options with reported transfusion rates up to 24% and 4%, respectively. The Aquablation procedure is a new, impressively fast, resective BPH surgical alternative harnessing image guidance, high velocity waterjet, and robotic standardized execution, with a rapid learning curve. While several techniques for hemostasis following Aquablation have been utilized, the optimal strategy has not been fully vetted across different prostate sizes. METHODS: The current commercial AQUABEAM robot that performs Aquablation Therapy was first used in 2014. Since then numerous clinical studies have been conducted in various countries; Australia, Canada, Germany, India, Lebanon, Spain, New Zealand, United Kingdom, and the United States. All of the clinical trial data since 2014 have been pooled with the early commercial procedures from France, Germany, and Spain. The objective is to determine if athermal methods are as effective in preventing blood transfusions as the use of cautery across various prostate volume sizes. RESULTS: 801 patients were treated with Aquablation Therapy from 2014 to early 2019. The average prostate volume was 67mL 33mL (range 20-280mL) where 31 (3.9%) transfusions were reported. The largest contributing factor to transfusion risk was prostate size and method of traction. There was an increasing risk of transfusions in larger prostates when robust traction using a catheter tensioning device without cautery ranging from 0.8% to 7.8% in prostates ranging from 20mL to 280mL. However, when standard traction (taping the catheter to the leg, gauze knot synched up to the meatus, or no traction at all) was used and where the surgeon performed bladder neck cautery only when necessary, the risk of transfusion 1.4% to 2.5% in prostates ranging from 20mL to 280mL. CONCLUSIONS: While the athermal subgroup with robust traction with a catheter tension device had comparable transfusion rates for smaller prostates, the risk increased significantly as prostate volume increased. With standard traction methods and selective bladder neck cautery, the risk of transfusion is reduced to a 1.9% across all prostate sizes.