Postoperative urinary retention: risk factors, bladder filling rate and time to catheterization: an observational study as part of a randomized controlled trial

Abstract Background Knowledge of risk factors for postoperative urinary retention may guide appropriate and timely catheterization. We aimed to determine independent catheterization in general surgical patients. In addition, we calculated bladder filling rate assessed the time spontaneous voiding or used patients previously determined individual maximum capacity as threshold Methods Risk were prospectively 936 Patients at least 18 years age operated under spinal anesthesia without need an indwelling catheter. measured their preoperatively home, by a calibrated bowl after strong urge that could no longer be ignored. Postoperatively, volumes hourly with ultrasound. When reached unable void, they catheterized nursing staff. Bladder determined. Results Spinal was main modifiable factor (hyperbaric bupivacaine, relative 8.1, articaine RR 3.1). Unmodifiable < 500 mL (RR 6.7), duration surgery ≥ 60 min 5.5), first scanned volume Post Anesthesia Care Unit ≥250mL 2.1), 2.0). Urine production varied from 100 200 mL/h. Catheterization took place approximately 4 h postoperatively. Conclusion anesthesia, time, older are Awareness these factors, regularly scanning (at every 3 h) using avoid unnecessary will prevent overdistention attendant lower tract injury. Trial registration Dutch Central Committee Human Studies registered trial database : NL 21058.099.07. Current Controlled Trials Preventing Operation General Using Patient’s Own Maximum Capacity Limit Volume. ISRCTN97786497 . Registered July 2011 -Retrospectively registered. The original study started 19 May 2008, ended 30 April 2009, when last patient included.