Following a transurethral resection of the prostate (TURP), the patient is closely monitored for adequate urine output; urethral patency is maintained with a continuous bladder irrigation (CBI) system. In the 6 hours following the procedure, the most likely reason for the decreased urine output is a clot blocking the outflow tract (caused by activation of the coagulation cascade). The CBI flow must be maintained at a sufficient rate to allow for the flushing of any clots that form. It is less likely that the patient is experiencing profound hypotension, which can cause acute prerenal kidney injury, because the procedure is generally well-tolerated. Although an IV infiltrate may cause decreased fluid intake, it is unlikely the patient did not inform the nurse of pain at the IV site.