Continuous Bladder Irrigation (CBI)

A patient can have a full drainage bag and still have a bladder that is filling. Irrigant contributes to every millilitre collected, so the bag's total volume cannot be read as urine output. The experienced nurse watches the relationship between inflow, return, and the patient's bladder—not the bag alone. CBI uses a three-way indwelling catheter: one lumen delivers sterile irrigant, one drains the bladder, and the balloon lumen maintains position. The goal is a patent outflow tract while bleeding or clot risk is present. A falling return, new suprapubic pressure, or increasing abdominal girth changes the task from flow adjustment to possible obstruction and urgent escalation.