Extensive perinephric hematoma following excessive irrigation pressure during flexible ureteroscopy: case report of a preventable complication

Flexible ureteroscopy (fURS) is widely regarded as a safe and effective procedure for the management of urolithiasis. Nevertheless, inadequate management of intrarenal pressure during fURS represents an underrecognized patient safety hazard. The use of high-pressure irrigation to compensate for poor visualization—particularly when outflow is restricted—may expose patients to prolonged supraphysiologic intrarenal pressure and preventable harm. I report a severe pressure-related renal injury following fURS and analyze the event using a human factors and systems-based root cause analysis framework. A 45-year-old man underwent fURS for a 1.5-cm proximal ureteral stone. A ureteral access sheath was not used due to a tight distal ureter. During the 100-min procedure, visualization progressively deteriorated because of mucosal edema, bleeding, and debris. Irrigation was escalated using a manual pressure bag and reported intraoperatively as very high (300–400 mmHg on the pressure bag gauge) for a prolonged period. Shortly following surgery, the patient developed severe flank pain and a high-grade fever. Computed tomography revealed a massive perinephric hematoma without active contrast extravasation. The patient remained hemodynamically stable and improved with conservative management. The described event is best understood as a preventable iatrogenic injury arising from a predictable hazard: pressure escalation to restore visualization. It occurred in a system without adequate defenses, namely, limited outflow, a lack of real-time pressure feedback, the absence of pressure or time stop rules, and insufficient team cross-checks against cognitive fixation. Intrarenal pressure should be treated as a critical safety variable in endourology. Pressure-governed workflows—prioritizing outflow augmentation, objective monitoring when feasible, and escalation pathways that favor staging over unmonitored pressure escalation—are essential to prevent similar harm.