How is post-void residual (PVR) urine measured, and what is a typical normal range?

• A. Measured with a bladder scanner or catheterization after voiding; normal PVR is usually <50–100 mL.
• B. Measured with a stethoscope; normal PVR is 500–600 mL.
• C. Measured by urine color; normal PVR is clear.
• D. Measured by heart rate; normal PVR is 0.

Answer: (A)

Post-void residual is the amount of urine left in the bladder after a person voids, used to assess how well the bladder empties. It is measured either with a bladder scanner (an ultrasound device that estimates the remaining volume) or by catheterizing after voiding to drain and measure the residual urine. A typical normal range is about 50 mL or less, though up to 100 mL can be considered normal in many adults. Values above this suggest incomplete bladder emptying and may indicate obstruction, poor detrusor muscle function, or other issues. The other methods listed don’t measure residual urine: a stethoscope can’t quantify bladder volume, urine color doesn’t reflect how much remains, and heart rate has no relation to PVR.