💧 CBI Calculator
True urine output during continuous bladder irrigation
About this calculator
Continuous bladder irrigation is used after prostate or bladder surgery, and the CBI calculator tracks fluid balance to estimate blood loss. Enter the total irrigation fluid infused and the total fluid collected in the drainage bag. Subtracting inflow from outflow gives the net output, which approximates blood loss mixed with urine. For educational purposes only — always verify with your facility's clinical protocols.
Tip: always check the color and clarity of the drainage too; a rising net output with bright red urine is more urgent than numbers alone suggest.