<i>In vitro</i> investigation of the optimal hydrogen peroxide dosage for bladder clots evacuation

Objective: Bladder clot retention after hematuria is a urological emergency.Traditional washout often fails, requiring endoscopic evacuation under general anesthesia -often inaccessible in remote or critical care settings.This study aimed to determine the optimal dose and dwell time of hydrogen peroxide (H 2 O 2 ) for enhancing clot evacuation.Method: In this in vitro study, 24 bladder clot models using 100 g of human blood were randomized into six groups and treated with 0.15%, 0.30%, or 0.60% H 2 O 2 or saline.Each model used a 750-mL transparent urinary bag with an 18 Fr Foley catheter.Instillations lasted 30 or 60 s and were repeated until clot clearance.Parameters measured included procedure difficulty, attempts, duration, and fluid volume.Results: All H 2 O 2 concentrations improved clot removal.The 0.30% group significantly reduced time and difficulty versus 0.15% (p < 0.05).Extending dwell time to 60 s did not enhance outcomes and prolonged the procedure.Although 0.60% was effective, it offered no significant advantage over 0.30%.Conclusions: Instilling 0.30% H 2 O 2 for 30 s appears most effective for clot evacuation.Further in vivo studies are recommended.